meCLICK-Seq, a Substrate-Hijacking and RNA Degradation Strategy for the Study of RNA Methylation
- Sigitas MikutisSigitas MikutisDepartment of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, U.K.More by Sigitas Mikutis,
- Muxin GuMuxin GuHaematological Cancer Genetics, Wellcome Trust Sanger Institute, Hinxton, Cambridge CB10 1SA, U.K.More by Muxin Gu,
- Erdem SendincErdem SendincBoston Childrens’ Hospital, Harvard Medical School, 300 Longwood Avenue, Boston, Massachusetts 02115, United StatesMore by Erdem Sendinc,
- Madoka E. HazemiMadoka E. HazemiDepartment of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, U.K.More by Madoka E. Hazemi,
- Hannah Kiely-CollinsHannah Kiely-CollinsDepartment of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, U.K.More by Hannah Kiely-Collins,
- Demetrios AsprisDemetrios AsprisHaematological Cancer Genetics, Wellcome Trust Sanger Institute, Hinxton, Cambridge CB10 1SA, U.K.The Center for the Study of Haematological Malignancies, Karaiskakio Foundation, Nicandrou Papamina Avenue, 2032 Nicosia, CyprusMore by Demetrios Aspris,
- George S. VassiliouGeorge S. VassiliouHaematological Cancer Genetics, Wellcome Trust Sanger Institute, Hinxton, Cambridge CB10 1SA, U.K.The Center for the Study of Haematological Malignancies, Karaiskakio Foundation, Nicandrou Papamina Avenue, 2032 Nicosia, CyprusWellcome-MRC Cambridge Stem Cell Institute, University of Cambridge, Puddicombe Way, Cambridge CB2 0AW, U.K.More by George S. Vassiliou,
- Yang ShiYang ShiBoston Childrens’ Hospital, Harvard Medical School, 300 Longwood Avenue, Boston, Massachusetts 02115, United StatesLudwig Institute for Cancer Research, Oxford University, Old Road Campus Research Build, Roosevelt Dr., Oxford OX3 7DQ, U.K.More by Yang Shi,
- Konstantinos Tzelepis*Konstantinos Tzelepis*E-mail: [email protected]Haematological Cancer Genetics, Wellcome Trust Sanger Institute, Hinxton, Cambridge CB10 1SA, U.K.Boston Childrens’ Hospital, Harvard Medical School, 300 Longwood Avenue, Boston, Massachusetts 02115, United StatesMilner Therapeutics Institute, University of Cambridge, Puddicombe Way, Cambridge CB2 0AW, U.K.More by Konstantinos Tzelepis, and
- Gonçalo J. L. Bernardes*Gonçalo J. L. Bernardes*E-mail: [email protected]Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, U.K.Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Avenida Professor Egas Moniz, 1649-028 Lisboa, PortugalMore by Gonçalo J. L. Bernardes
Abstract

The fates of RNA species in a cell are controlled by ribonucleases, which degrade them by exploiting the universal structural 2′-OH group. This phenomenon plays a key role in numerous transformative technologies, for example, RNA interference and CRISPR/Cas13-based RNA editing systems. These approaches, however, are genetic or oligomer-based and so have inherent limitations. This has led to interest in the development of small molecules capable of degrading nucleic acids in a targeted manner. Here we describe click-degraders, small molecules that can be covalently attached to RNA species through click-chemistry and can degrade them, that are akin to ribonucleases. By using these molecules, we have developed the meCLICK-Seq (methylation CLICK-degradation Sequencing) a method to identify RNA modification substrates with high resolution at intronic and intergenic regions. The method hijacks RNA methyltransferase activity to introduce an alkyne, instead of a methyl, moiety on RNA. Subsequent copper(I)-catalyzed azide–alkyne cycloaddition reaction with the click-degrader leads to RNA cleavage and degradation exploiting a mechanism used by endogenous ribonucleases. Focusing on N6-methyladenosine (m6A), meCLICK-Seq identifies methylated transcripts, determines RNA methylase specificity, and reliably maps modification sites in intronic and intergenic regions. Importantly, we show that METTL16 deposits m6A to intronic polyadenylation (IPA) sites, which suggests a potential role for METTL16 in IPA and, in turn, splicing. Unlike other methods, the readout of meCLICK-Seq is depletion, not enrichment, of modified RNA species, which allows a comprehensive and dynamic study of RNA modifications throughout the transcriptome, including regions of low abundance. The click-degraders are highly modular and so may be exploited to study any RNA modification and design new technologies that rely on RNA degradation.
Synopsis
RNA methylation controls many biological processes. We describe a small molecule-based platform to hijack RNA methylation by guided degradation for high resolution profiling of modified substrates.
Figure 1

Figure 1. meCLICK-Seq, a small molecule-based methylated RNA editing platform. (a) Proposed mechanism of action of meCLICK-Seq. (b) Conversion of PropSeMet into SeAdoYn and subsequent introduction of propargyl groups into RNA. (c) Functionalization of propargylated RNA with the click-degrader. (d) Proposed mechanism of the general base RNA degradation. (e) Copper-mediated RNA degradation.
Results and Discussion
Click-Degraders Function through a Dual Chemical Mechanism
Figure 2

Figure 2. Study of the chemical mechanism of click-degraders. (a) Time-dependent degradation of click-degrader 1 functionalized RNA 11-mer at 37 °C. n = 2. (b) Extent of RNA degradation after 14 h at 37 °C, pH 7.5, n = 2. (c) Extent of RNA degradation after 14 h at 37 °C, pH 3.0, n = 2. (d) Extent of RNA degradation in neutral and acidic conditions, n = 2. (e) Extent of RNA degradation after 14 h at 37 °C, pH 7.5, with PEG linkers of differing lengths. Cinitial corresponds to initial concentration; C corresponds to concentration at a specified time point. Click-degraders 1, 2, and 3 have linkers with 6, 4, and 2 PEG subunits, respectively, n = 2. Error bars represent SD.
Elucidation of mRNA Substrates of m6A Writers
Figure 3

Figure 3. meCLICK-Seq elucidates the relationship between m6A writers and methylation of mRNAs and lncRNAs. (a) meCLICK-Seq workflow. (b) Western blots demonstrate the extent of METTL3 and METTL16 depletion in conditional knock-down MOLM-13 cells treated with PropSeMet. Application of click-degrader does not significantly alter the levels of MTases. (c) Heat map showing decrease of methylated mRNA levels upon clicking and rescue of METTL3-dependent transcripts upon METTL3 depletion. (d) Overlap of m6A-containing mRNAs determined through m6A miCLIP and METTL3 mRNA substrates determined by meCLICK-Seq; significance indicated by Fisher’s exact test. (e) RT-qPCR-based meCLICK-Seq validation of a panel of genes, n = 3. (f) RT-qPCR-based meCLICK-Seq validation of a panel of genes in METTL3 depleted cells, n = 3. (g) Genome browser snapshot of NEAT1. Applying click machinery diminishes the WT but not METTL3 or METTL16 levels. p values determined with one-tailed t test. ns = not significant (p ≥ 0.05). Error bars represent SD.
Many lncRNAs Are METTL3 or METTL16 Substrates
meCLICK-Seq Reveals That m6A Is Widespread in Intronic and Intergenic Regions
Figure 4

Figure 4. meCLICK-Seq reveals widespread m6A mark in introns and intergenic regions. (a) Intronic peaks in the first intron of FLI1. (b) Intronic peaks in the first intron of CADM1 in three isogenic cell models. Intronic peaks are abolished specifically in METTL16-KD cells. (c) Overlap between METTL3- and METTL16-dependent intronic peaks. (d) Distribution of METTL3-dependent peaks in intronic and intergenic regions. (e) Distribution of METTL16-dependent peaks in intronic and intergenic regions. (f) RT-qPCR-based validation of a panel intronic peaks, n = 3. (g) Validation of dependence of intronic peaks on RNA methylases METTL3 and METTL16, n = 3. (h) Results of m6A-RIP in cells with methylated introns removed by dual gRNA system, n = 3. (i) Results of m6A-RIP in cells with depleted METTL3, n = 3. (j) Results of m6A-RIP in cells with depleted METTL16. RASA3 peak 2 is not affected by the knock-down illustrating that the observed effect is enzyme-specific, n = 3. ns = not significant (p ≥ 0.05). Error bars represent SD.
meCLICK-Seq Can Determine Substrates for Other RNA Methylations
METTL16 Is Linked to Intronic Polyadenylation Sites
Conclusions
Experimental Section
In Vitro Click-Degrader Functionalization Reactions
LCMS Analysis of Oligonucleotides
RNA Degradation Gel Electrophoresis
Cell Culture
Lentiviral Vector Production, Infection, and Transfection
Generation of Conditional Knock-down and Intronic Deletion-Containing Cells
Cellular RNA Degradation Reactions (meCLICK-Seq)
m6A RNA Immunoprecipitation
RNA Extraction, Reverse Transcription, and RT-qPCR
Statistical Analysis
Protein Extraction and Immunoblotting
HPLC-MS/MS Analysis of RNA
Biotin Pull-down Experiment
Bioinformatic Analysis
The Supporting Information is available free of charge at https://pubs.acs.org/doi/10.1021/acscentsci.0c01094.
Putative mass spectra peaks for the 11-mer after 2 hour degradation and for the functionalized and BCS-quenched 11-mer after 14 hour degradation, detected RNA species, oligomers used for the in vitro study, list of primers and gRNAs, analysis of propargylated and non-propargylated RNA oligomers degradation by click-degrader, predicted structures of oligomers used, analyses of CTRL and Prop oligomers, analysis of mRNA and lncRNA species, examples of intronic peak snapshots, analyses of METTL3- and METTL16-dependent peaks, comparison of methylated mRNAs determined via meCLICK-Seq and m7G-Seq, analysis of MeCLICK-Seq peaks and IPA sites, mass spectra of functionalized 11-mer species, and chemical synthesis and characterization including NMR spectra (PDF)
METTL3 and METTL16 mRNA substrates determined via meCLICK-Seq (TXT)
Results of a miCLIP study of m6A in MOLM13 cells (XLSX)
METTL3 and METTL16 lncRNA substrates determined via meCLICK-Seq (TXT)
METTL13 and METTL16-dependent intronic/intergenic peaks determined via meCLICK-Seq (XLSX)
Methylated mRNA species determined via meCLICK-Seq with an overlap with m7G-Seq study (XLSX)
Intronic and intergenic click-degrader sensitive RNA peaks with an overlap with m7G-Seq study (XLSX)
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Acknowledgments
We thank UKRI (BBSRC DTP scholarships to S.M. and H.K.C) and the Jardine Foundation and Cambridge Trust (Ph.D. scholarship to M.E.H.). K.T. was funded by a Wellcome Trust Sir Henry Wellcome Fellowship (grant reference RG94424). G.S.V. is funded by a Cancer Research UK Senior Cancer Fellowship (C22324/A23015). Research in the Shi lab is supported by Ludwig Institute for Cancer Research. Y.S. is American Cancer Society Research Professor. G.J.L.B. is a Royal Society University Research Fellow (URF\R\180019) and an FCT Investigator (IF/00624/2015). We thank Dr. Vikki Cantrill for her help with the editing of this manuscript.
References
This article references 50 other publications.
- 1Meyer, S.; Temme, C.; Wahle, E. Messenger RNA Turnover in Eukaryotes: Pathways and Enzymes. Crit. Rev. Biochem. Mol. Biol. 2004, 39 (4), 197– 216, DOI: 10.1080/10409230490513991[Crossref], [PubMed], [CAS], Google Scholar1https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD2cXovFGgsbY%253D&md5=7aa734bab93387c9f1519ae68c546e88Messenger RNA Turnover in Eukaryotes: Pathways and EnzymesMeyer, Sylke; Temme, Claudia; Wahle, ElmarCritical Reviews in Biochemistry and Molecular Biology (2004), 39 (4), 197-216CODEN: CRBBEJ; ISSN:1040-9238. (Taylor & Francis, Inc.)A review. The control of mRNA degrdn. is an important component of the regulation of gene expression since the steady-state concn. of mRNA is detd. both by the rates of synthesis and of decay. Two general pathways of mRNA decay have been described in eukaryotes. Both pathways share the exonucleolytic removal of the poly(A) tail (deadenylation) as the first step. In one pathway, deadenylation is followed by the hydrolysis of the cap and processive degrdn. of the mRNA body by a 5'exonuclease. In the second pathway, the mRNA body is degraded by a complex of 3'exonucleases before the remaining cap structure is hydrolyzed. This review discusses the proteins involved in the catalysis and control of both decay pathways.
- 2Shu, X.; Cao, J.; Cheng, M.; Xiang, S.; Gao, M.; Li, T.; Ying, X.; Wang, F.; Yue, Y.; Lu, Z.; Dai, Q.; Cui, X.; Ma, L.; Wang, Y.; He, C.; Feng, X.; Liu, J. A metabolic labeling method detects m6A transcriptome-wide at single base resolution. Nat. Chem. Biol. 2020, 16 (8), 887– 895, DOI: 10.1038/s41589-020-0526-9[Crossref], [PubMed], [CAS], Google Scholar2https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BB3cXotVCjur0%253D&md5=1793171884fef97b342913c2b6b847d3A metabolic labeling method detects m6A transcriptome-wide at single base resolutionShu, Xiao; Cao, Jie; Cheng, Mohan; Xiang, Siying; Gao, Minsong; Li, Ting; Ying, Xiner; Wang, Fengqin; Yue, Yanan; Lu, Zhike; Dai, Qing; Cui, Xiaolong; Ma, Lijia; Wang, Yizhen; He, Chuan; Feng, Xinhua; Liu, JianzhaoNature Chemical Biology (2020), 16 (8), 887-895CODEN: NCBABT; ISSN:1552-4450. (Nature Research)Transcriptome-wide mapping of N6-methyladenosine (m6A) at base resoln. remains an issue, impeding the authors' understanding of m6A roles at the nucleotide level. Here, the authors report a metabolic labeling method to detect mRNA m6A transcriptome-wide at base resoln., called 'm6A-label-seq'. Human and mouse cells could be fed with a methionine analog, Se-allyl-L-selenohomocysteine, which substitutes the Me group on the enzyme cofactor SAM with the allyl. Cellular RNAs could therefore be metabolically modified with N6-allyladenosine (a6A) at supposed m6A-generating adenosine sites. The authors pinpointed the mRNA a6A locations based on iodination-induced misincorporation at the opposite site in complementary DNA during reverse transcription. The authors identified a few thousand mRNA m6A sites in human HeLa, HEK293T and mouse H2.35 cells, carried out a parallel comparison of m6A-label-seq with available m6A sequencing methods, and validated selected sites by an orthogonal method. This method offers advantages in detecting clustered m6A sites and holds promise to locate nuclear nascent RNA m6A modifications.
- 3Shi, Y. Mechanistic insights into precursor messenger RNA splicing by the spliceosome. Nat. Rev. Mol. Cell Biol. 2017, 18 (11), 655– 670, DOI: 10.1038/nrm.2017.86[Crossref], [PubMed], [CAS], Google Scholar3https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2sXhsFKisb%252FE&md5=cbd7c32a25d27aa9e6958bab679e5869Mechanistic insights into precursor messenger RNA splicing by the spliceosomeShi, YigongNature Reviews Molecular Cell Biology (2017), 18 (11), 655-670CODEN: NRMCBP; ISSN:1471-0072. (Nature Research)A review. Precursor mRNA (pre-mRNA) splicing is an essential step in the flow of information from DNA to protein in all eukaryotes. Research over the past four decades has molecularly delineated the splicing pathway, including characterization of the detailed splicing reaction, definition of the spliceosome and identification of its components, and biochem. anal. of the various splicing complexes and their regulation. Structural information is central to mechanistic understanding of pre-mRNA splicing by the spliceosome. X-ray crystallog. of the spliceosomal components and subcomplexes is complemented by electron microscopy of the intact spliceosome. In this Review, I discuss recent at.-resoln. structures of the intact spliceosome at different stages of the splicing cycle. These structures have provided considerable mechanistic insight into pre-mRNA splicing and have corroborated and explained a large body of genetic and biochem. data. Together, the structural data have proved that the spliceosome is a protein-directed metalloribozyme.
- 4Chakrabarti, A.; Jha, B. K.; Silverman, R. H. New Insights into the Role of RNase L in Innate Immunity. J. Interferon Cytokine Res. 2011, 31 (1), 49– 57, DOI: 10.1089/jir.2010.0120[Crossref], [PubMed], [CAS], Google Scholar4https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3MXlt1Omuw%253D%253D&md5=fd42c2c66f4de908799e5b96d705ff1fNew Insights into the Role of RNase L in Innate ImmunityChakrabarti, Arindam; Jha, Babal Kant; Silverman, Robert H.Journal of Interferon & Cytokine Research (2011), 31 (1), 49-57CODEN: JICRFJ; ISSN:1079-9907. (Mary Ann Liebert, Inc.)A review. The interferon (IFN)-inducible 2'-5'-oligoadenylate synthetase (OAS)/RNase L pathway blocks infections by some types of viruses through cleavage of viral and cellular single-stranded RNA. Viruses induce type I IFNs that initiate signaling to the OAS genes. OAS proteins are pathogen recognition receptors for the viral pathogen-assocd. mol. pattern, double-stranded RNA. Double-stranded RNA activates OAS to produce px5'A(2'p5'A)n; x = 1-3; n > 2 (2-5A) from ATP. Upon binding 2-5A, RNase L is converted from an inactive monomer to a potently active dimeric endoribonuclease for single-stranded RNA. RNase L contains, from N- to C-terminus, a series of 9 ankyrin repeats, a linker, several protein kinase-like motifs, and a RNase domain homologous to Ire1 (involved in the unfolded protein response). In the past few years, it has become increasingly apparent that RNase L and OAS contribute to innate immunity in many ways. For example, small RNA cleavage products produced by RNase L during viral infections can signal to the retinoic acid-inducible-I like receptors to amplify and perpetuate signaling to the IFN-β gene. In addn., RNase L is now implicated in protecting the central nervous system against viral-induced demyelination. A role in tumor suppression was inferred by mapping of the RNase L gene to the hereditary prostate cancer 1 (HPC1) gene, which in turn led to discovery of the xenotropic murine leukemia-related virus. A broader role in innate immunity is suggested by involvement of RNase L in cytokine induction and endosomal pathways that suppress bacterial infections. These newly described findings about RNase L could eventually provide the basis for developing broad-spectrum antimicrobial drugs.
- 5Deng, Y.; Wang, C. C.; Choy, K. W.; Du, Q.; Chen, J.; Wang, Q.; Li, L.; Chung, T. K. H.; Tang, T. Therapeutic potentials of gene silencing by RNA interference: Principles, challenges, and new strategies. Gene 2014, 538 (2), 217– 227, DOI: 10.1016/j.gene.2013.12.019[Crossref], [PubMed], [CAS], Google Scholar5https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2cXhs1Clt7w%253D&md5=cafe0ad284fd463c6cd9c3b5757de4f1Therapeutic potentials of gene silencing by RNA interference: Principles, challenges, and new strategiesDeng, Yan; Wang, Chi Chiu; Choy, Kwong Wai; Du, Quan; Chen, Jiao; Wang, Qin; Li, Lu; Chung, Tony Kwok Hung; Tang, TaoGene (2014), 538 (2), 217-227CODEN: GENED6; ISSN:0378-1119. (Elsevier B.V.)A review. During recent decades there have been remarkable advances in biol., in which one of the most important discoveries is RNA interference (RNAi). RNAi is a specific post-transcriptional regulatory pathway that can result in silencing gene functions. Efforts have been done to translate this new discovery into clin. applications for disease treatment. However, tech. difficulties restrict the development of RNAi, including stability, off-target effects, immunostimulation and delivery problems. Researchers have attempted to surmount these barriers and improve the bioavailability and safety of RNAi-based therapeutics by optimizing the chem. and structure of these mols. This paper aimed to describe the principles of RNA interference, review the therapeutic potential in various diseases and discuss the new strategies for in vivo delivery of RNAi to overcome the challenges.
- 6Cox, D. B. T.; Gootenberg, J. S.; Abudayyeh, O. O.; Franklin, B.; Kellner, M. J.; Joung, J.; Zhang, F. RNA editing with CRISPR-Cas13. Science 2017, 358 (6366), 1019, DOI: 10.1126/science.aaq0180[Crossref], [PubMed], [CAS], Google Scholar6https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2sXhvFahsb3J&md5=21ed8ebbd2cc334be0911129196e6b6eRNA editing with CRISPR-Cas13Cox, David B. T.; Gootenberg, Jonathan S.; Abudayyeh, Omar O.; Franklin, Brian; Kellner, Max J.; Joung, Julia; Zhang, FengScience (Washington, DC, United States) (2017), 358 (6366), 1019-1027CODEN: SCIEAS; ISSN:0036-8075. (American Association for the Advancement of Science)Nucleic acid editing holds promise for treating genetic disease, particularly at the RNA level, where disease-relevant sequences can be rescued to yield functional protein products. Type VI CRISPR-Cas systems contain the programmable single-effector RNA-guided RNase Cas13. We profiled type VI systems in order to engineer a Cas13 ortholog capable of robust knockdown and demonstrated RNA editing by using catalytically inactive Cas13 (dCas13) to direct adenosine-to-inosine deaminase activity by ADAR2 (adenosine deaminase acting on RNA type 2) to transcripts in mammalian cells. This system, referred to as RNA editing for programmable A to I replacement (REPAIR), which has no strict sequence constraints, can be used to edit full-length transcripts contg. pathogenic mutations. We further engineered this system to create a high-specificity variant and minimized the system to facilitate viral delivery. REPAIR presents a promising RNA-editing platform with broad applicability for research, therapeutics, and biotechnol.
- 7Costales, M. G.; Matsumoto, Y.; Velagapudi, S. P.; Disney, M. D. Small Molecule Targeted Recruitment of a Nuclease to RNA. J. Am. Chem. Soc. 2018, 140 (22), 6741– 6744, DOI: 10.1021/jacs.8b01233[ACS Full Text
], [CAS], Google Scholar7https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1cXpvFKktbs%253D&md5=7d4ccaad0cba3da84f924f244b8bcdbfSmall Molecule Targeted Recruitment of a Nuclease to RNACostales, Matthew G.; Matsumoto, Yasumasa; Velagapudi, Sai Pradeep; Disney, Matthew D.Journal of the American Chemical Society (2018), 140 (22), 6741-6744CODEN: JACSAT; ISSN:0002-7863. (American Chemical Society)The choreog. between RNA synthesis and degrdn. is a key determinant in biol. Engineered systems such as CRISPR have been developed to rid a cell of RNAs. Here, we show that a small mol. can recruit a nuclease to a specific transcript, triggering its destruction. A small mol. that selectively binds the oncogenic microRNA(miR)-96 hairpin precursor was appended with a short 2'-5' poly(A) oligonucleotide. The conjugate locally activated endogenous, latent RNase (RNase L), which selectively cleaved the miR-96 precursor in cancer cells in a catalytic fashion. Silencing miR-96 de-repressed pro-apoptotic FOXO1 transcription factor, triggering apoptosis in breast cancer, but not healthy breast, cells. These results demonstrate that small mols. can be programmed to selectively cleave RNA and has broad implications. - 8Li, Y.; Disney, M. D. Precise Small Molecule Degradation of a Noncoding RNA Identifies Cellular Binding Sites and Modulates an Oncogenic Phenotype. ACS Chem. Biol. 2018, 13 (11), 3065– 3071, DOI: 10.1021/acschembio.8b00827[ACS Full Text
], [CAS], Google Scholar8https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1cXitVamtbbP&md5=1d67850e24a1ed7eda6dbf2f26ea2a68Precise Small Molecule Degradation of a Noncoding RNA Identifies Cellular Binding Sites and Modulates an Oncogenic PhenotypeLi, Yue; Disney, Matthew D.ACS Chemical Biology (2018), 13 (11), 3065-3071CODEN: ACBCCT; ISSN:1554-8929. (American Chemical Society)Herein, we describe the precise cellular destruction of an oncogenic noncoding RNA with a small mol.-bleomycin A5 conjugate, affording reversal of phenotype and a facile method to map the cellular binding sites of a small mol. In particular, bleomycin A5 was coupled to a small mol. that selectively binds the microRNA-96 hairpin precursor (pri-miR-96). By coupling of bleomycin A5's free amine to the RNA binder, its affinity for binding to pri-miR-96 is >100-fold stronger than to DNA and the compd. selectively cleaves pri-miR-96 in triple neg. breast cancer (TNBC) cells. Indeed, selective cleavage of pri-miR-96 enhanced expression of FOXO1 protein, a pro-apoptotic transcription factor that miR-96 silences, and triggered apoptosis in TNBC cells. No effects were obsd. in healthy breast epithelial cells. Thus, conjugation to bleomycin A5's free amine may provide programmable control over its cellular targets. Few approaches are available to define the binding sites of small mols. within cellular RNAs. Our targeted cleavage approach provides such an approach that is straightforward to implement. That is, we detd. exptl. the site cleaved within pri-miR-96 in vitro and in cells; these studies revealed that the site of cleavage is the precise site for which the small mol. cleaver was designed and in agreement with modeling. These studies demonstrate the potential of sequence-based design to provide bioactive compds. that precisely recognize and cleave RNA in cells. - 9Tomkuviene, M.; Clouet-d’Orval, B.; Cerniauskas, I.; Weinhold, E.; Klimasauskas, S. Programmable sequence-specific click-labeling of RNA using archaeal box C/D RNP methyltransferases. Nucleic Acids Res. 2012, 40 (14), 6765– 6773, DOI: 10.1093/nar/gks381[Crossref], [PubMed], [CAS], Google Scholar9https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC38XhtF2rsLrE&md5=4e81250f3e4678cd15e0f0a98ddbf019Programmable sequence-specific click-labeling of RNA using archaeal box C/D RNP methyltransferasesTomkuviene, Migle; Clouet-d'Orval, Beatrice; Cerniauskas, Ignas; Weinhold, Elmar; Klimasauskas, SauliusNucleic Acids Research (2012), 40 (14), 6765-6773CODEN: NARHAD; ISSN:0305-1048. (Oxford University Press)Biophys. and mechanistic investigation of RNA function requires site-specific incorporation of spectroscopic and chem. probes, which is difficult to achieve using current technologies. We have in vitro reconstituted a functional box C/D small ribonucleoprotein RNA 2'-O-methyltransferase (C/D RNP) from the thermophilic archaeon Pyrococcus abyssi and demonstrated its ability to transfer a prop-2-ynyl group from a synthetic cofactor analog to a series of preselected target sites in model tRNA and pre-mRNA mols. Target selection of the RNP was programmed by changing a dodecanucleotide guide sequence in a 64-nt C/D guide RNA leading to efficient derivatization of three out of four new targets in each RNA substrate. We also show that the transferred terminal alkyne can be further appended with a fluorophore using a bioorthogonal azide-alkyne 1,3-cycloaddn. (click) reaction. The described approach for the first time permits synthetically tunable sequence-specific labeling of RNA with single-nucleotide precision.
- 10Meyer, K. D.; Saletore, Y.; Zumbo, P.; Elemento, O.; Mason, C. E.; Jaffrey, S. R. Comprehensive analysis of mRNA methylation reveals enrichment in 3′ UTRs and near stop codons. Cell 2012, 149 (7), 1635– 1646, DOI: 10.1016/j.cell.2012.05.003[Crossref], [PubMed], [CAS], Google Scholar10https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC38Xntlyrs7s%253D&md5=e0547faf06ce7cc5279c34d9ebb6f808Comprehensive analysis of mRNA methylation reveals enrichment in 3' UTRs and near stop codonsMeyer, Kate D.; Saletore, Yogesh; Zumbo, Paul; Elemento, Olivier; Mason, Christopher E.; Jaffrey, Samie R.Cell (Cambridge, MA, United States) (2012), 149 (7), 1635-1646CODEN: CELLB5; ISSN:0092-8674. (Cell Press)Methylation of the N6 position of adenosine (m6A) is a posttranscriptional modification of RNA with poorly understood prevalence and physiol. relevance. The recent discovery that FTO, an obesity risk gene, encodes an m6A demethylase implicates m6A as an important regulator of physiol. processes. Here, we present a method for transcriptome-wide m6A localization, which combines m6A-specific methylated RNA immunopptn. with next-generation sequencing (MeRIP-Seq). We use this method to identify mRNAs of 7676 mammalian genes that contain m6A, indicating that m6A is a common base modification of mRNA. The m6A modification exhibits tissue-specific regulation and is markedly increased throughout brain development. We find that m6A sites are enriched near stop codons and in 3' UTRs, and we uncover an assocn. between m6A residues and microRNA-binding sites within 3' UTRs. These findings provide a resource for identifying transcripts that are substrates for adenosine methylation and reveal insights into the epigenetic regulation of the mammalian transcriptome.
- 11Dominissini, D.; Moshitch-Moshkovitz, S.; Schwartz, S.; Salmon-Divon, M.; Ungar, L.; Osenberg, S.; Cesarkas, K.; Jacob-Hirsch, J.; Amariglio, N.; Kupiec, M.; Sorek, R.; Rechavi, G. Topology of the human and mouse m6A RNA methylomes revealed by m6A-seq. Nature 2012, 485 (7397), 201– 206, DOI: 10.1038/nature11112[Crossref], [PubMed], [CAS], Google Scholar11https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC38XmvVequ7g%253D&md5=e392a6533a536e9c142488a6ca3f678dTopology of the human and mouse m6A RNA methylomes revealed by m6A-seqDominissini, Dan; Moshitch-Moshkovitz, Sharon; Schwartz, Schraga; Salmon-Divon, Mali; Ungar, Lior; Osenberg, Sivan; Cesarkas, Karen; Jacob-Hirsch, Jasmine; Amariglio, Ninette; Kupiec, Martin; Sorek, Rotem; Rechavi, GideonNature (London, United Kingdom) (2012), 485 (7397), 201-206CODEN: NATUAS; ISSN:0028-0836. (Nature Publishing Group)An extensive repertoire of modifications is known to underlie the versatile coding, structural and catalytic functions of RNA, but it remains largely uncharted territory. Although biochem. studies indicate that N6-methyladenosine (m6A) is the most prevalent internal modification in mRNA, an in-depth study of its distribution and functions has been impeded by a lack of robust anal. methods. Here, we present the human and mouse m6A modification landscape in a transcriptome-wide manner, using a novel approach, m6A-seq, based on antibody-mediated capture and massively parallel sequencing. We identify over 12,000 m6A sites characterized by a typical consensus in the transcripts of more than 7,000 human genes. Sites preferentially appear in two distinct landmarks-around stop codons and within long internal exons-and are highly conserved between human and mouse. Although most sites are well preserved across normal and cancerous tissues and in response to various stimuli, a subset of stimulus-dependent, dynamically modulated sites is identified. Silencing the m6A methyltransferase significantly affects gene expression and alternative splicing patterns, resulting in modulation of the p53 (also known as TP53) signalling pathway and apoptosis. Our findings therefore suggest that RNA decoration by m6A has a fundamental role in regulation of gene expression.
- 12Linder, B.; Grozhik, A. V.; Olarerin-George, A. O.; Meydan, C.; Mason, C. E.; Jaffrey, S. R. Single-nucleotide-resolution mapping of m6A and m6Am throughout the transcriptome. Nat. Methods 2015, 12 (8), 767– 772, DOI: 10.1038/nmeth.3453[Crossref], [PubMed], [CAS], Google Scholar12https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2MXhtFWqur%252FE&md5=9d4f101a6ed91bb0ee5fa37be8530b51Single-nucleotide-resolution mapping of m6A and m6Am throughout the transcriptomeLinder, Bastian; Grozhik, Anya V.; Olarerin-George, Anthony O.; Meydan, Cem; Mason, Christopher E.; Jaffrey, Samie R.Nature Methods (2015), 12 (8), 767-772CODEN: NMAEA3; ISSN:1548-7091. (Nature Publishing Group)N6-methyladenosine (m6A) is the most abundant modified base in eukaryotic mRNA and has been linked to diverse effects on mRNA fate. Current mapping approaches localize m6A residues to transcript regions 100-200 nt long but cannot identify precise m6A positions on a transcriptome-wide level. Here we developed m6A individual-nucleotide-resoln. crosslinking and immunopptn. (miCLIP) and used it to demonstrate that antibodies to m6A can induce specific mutational signatures at m6A residues after UV light-induced antibody-RNA crosslinking and reverse transcription. We found that these antibodies similarly induced mutational signatures at N6,2'-O-dimethyladenosine (m6Am), a modification found at the first nucleotide of certain mRNAs. Using these signatures, we mapped m6A and m6Am at single-nucleotide resoln. in human and mouse mRNA and identified small nucleolar RNAs (snoRNAs) as a new class of m6A-contg. non-coding RNAs (ncRNAs).
- 13Zhang, Z.; Chen, L.-Q.; Zhao, Y.-L.; Yang, C.-G.; Roundtree, I. A.; Zhang, Z.; Ren, J.; Xie, W.; He, C.; Luo, G.-Z. Single-base mapping of m6A by an antibody-independent method. Sci. Adv. 2019, 5 (7), eaax0250, DOI: 10.1126/sciadv.aax0250
- 14Meyer, K. D. DART-seq: an antibody-free method for global m6A detection. Nat. Methods 2019, 16 (12), 1275– 1280, DOI: 10.1038/s41592-019-0570-0[Crossref], [PubMed], [CAS], Google Scholar14https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1MXhvVarsb3I&md5=2578ff8833ee276fc2bb75929fa9fcb3DART-seq: an antibody-free method for global m6A detectionMeyer, Kate D.Nature Methods (2019), 16 (12), 1275-1280CODEN: NMAEA3; ISSN:1548-7091. (Nature Research)N6-methyladenosine (m6A) is a widespread RNA modification that influences nearly every aspect of the mRNA lifecycle. Our understanding of m6A has been facilitated by the development of global m6A mapping methods, which use antibodies to immunoppt. methylated RNA. However, these methods have several limitations, including high input RNA requirements and cross-reactivity to other RNA modifications. Here, we present DART-seq (deamination adjacent to RNA modification targets), an antibody-free method for detecting m6A sites. In DART-seq, the cytidine deaminase APOBEC1 is fused to the m6A-binding YTH domain. APOBEC1-YTH expression in cells induces C-to-U deamination at sites adjacent to m6A residues, which are detected using std. RNA-seq. DART-seq identifies thousands of m6A sites in cells from as little as 10 ng of total RNA and can detect m6A accumulation in cells over time. Addnl., we use long-read DART-seq to gain insights into m6A distribution along the length of individual transcripts.
- 15Wang, Y.; Xiao, Y.; Dong, S.; Yu, Q.; Jia, G. Antibody-free enzyme-assisted chemical approach for detection of N6-methyladenosine. Nat. Chem. Biol. 2020, 16 (8), 896– 903, DOI: 10.1038/s41589-020-0525-x[Crossref], [PubMed], [CAS], Google Scholar15https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BB3cXotVCjur8%253D&md5=9d542adbb5a0272f274f6f6c5af60208Antibody-free enzyme-assisted chemical approach for detection of N6-methyladenosineWang, Ye; Xiao, Yu; Dong, Shunqing; Yu, Qiong; Jia, GuifangNature Chemical Biology (2020), 16 (8), 896-903CODEN: NCBABT; ISSN:1552-4450. (Nature Research)The inert chem. property of RNA modification N6-methyladenosine (m6A) makes it very challenging to detect. Most m6A sequencing methods rely on m6A-antibody immunopptn. and cannot distinguish m6A and N6,2'-O-dimethyladenosine modification at the cap +1 position (cap m6Am). Although the two antibody-free methods (m6A-REF-seq/MAZTER-seq and DART-seq) have been developed recently, they are dependent on m6A sequence or cellular transfection. Here, the authors present an antibody-free, FTO-assisted chem. labeling method termed m6A-SEAL for specific m6A detection. The authors applied m6A-SEAL to profile m6A landscapes in humans and plants, which displayed the known m6A distribution features in transcriptome. By doing a comparison with all available m6A sequencing methods and specific m6A sites validation by SELECT, m6A-SEAL has good sensitivity, specificity and reliability for transcriptome-wide detection of m6A. Given its tagging ability and FTO's oxidn. property, m6A-SEAL enables many applications such as enrichment, imaging and sequencing to drive future functional studies of m6A and other modifications.
- 16Hartstock, K.; Nilges, B. S.; Ovcharenko, A.; Cornelissen, N. V.; Püllen, N.; Lawrence-Dörner, A.-M.; Leidel, S. A.; Rentmeister, A. Enzymatic or In Vivo Installation of Propargyl Groups in Combination with Click Chemistry for the Enrichment and Detection of Methyltransferase Target Sites in RNA. Angew. Chem., Int. Ed. 2018, 57 (21), 6342– 6346, DOI: 10.1002/anie.201800188[Crossref], [CAS], Google Scholar16https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1cXlt1Ons7c%253D&md5=0c9d3948a841e3dfbda54d58120a80eeEnzymatic or In Vivo Installation of Propargyl Groups in Combination with Click Chemistry for the Enrichment and Detection of Methyltransferase Target Sites in RNAHartstock, Katja; Nilges, Benedikt S.; Ovcharenko, Anna; Cornelissen, Nicolas V.; Puellen, Nikolai; Lawrence-Doerner, Ann-Marie; Leidel, Sebastian A.; Rentmeister, AndreaAngewandte Chemie, International Edition (2018), 57 (21), 6342-6346CODEN: ACIEF5; ISSN:1433-7851. (Wiley-VCH Verlag GmbH & Co. KGaA)N6-methyladenosine (m6A) is the most abundant internal modification in eukaryotic mRNA. It is introduced by METTL3-METTL14 and tunes mRNA metab., impacting cell differentiation and development. Precise transcriptome-wide assignment of m6A sites is of utmost importance. However, m6A does not interfere with Watson-Crick base pairing, making polymerase-based detection challenging. We developed a chem. biol. approach for the precise mapping of methyltransferase (MTase) target sites based on the introduction of a bioorthogonal propargyl group in vitro and in cells. We show that propargyl groups can be introduced enzymically by wild-type METTL3-METTL14. Reverse transcription terminated up to 65 % at m6A sites after bioconjugation and purifn., hence enabling detection of METTL3-METTL14 target sites by next generation sequencing. Importantly, we implemented metabolic propargyl labeling of RNA MTase target sites in vivo based on propargyl-L-selenohomocysteine and validated different types of known rRNA methylation sites.
- 17Raines, R. T. Ribonuclease A. Chem. Rev. 1998, 98 (3), 1045– 1066, DOI: 10.1021/cr960427h[ACS Full Text
], [CAS], Google Scholar17https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaK1cXis12it7g%253D&md5=1e71aeda7dc7d4b6ac23f8c8ce8c2febRibonuclease ARaines, Ronald T.Chemical Reviews (Washington, D. C.) (1998), 98 (3), 1045-1065CODEN: CHREAY; ISSN:0009-2665. (American Chemical Society)A review with 420 refs., of the structure and function of RNase A, with emphasis on applications of recombinant DNA technol. and nucleic acid chem. - 18Cheng, L.; Abhilash, K. G.; Breslow, R. Binding and biomimetic cleavage of the RNA poly(U) by synthetic polyimidazoles. Proc. Natl. Acad. Sci. U. S. A. 2012, 109 (32), 12884, DOI: 10.1073/pnas.1210846109[Crossref], [PubMed], [CAS], Google Scholar18https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC38XhsVWmsrvL&md5=be5ae7559f5f5f9d0287738d97d985a5Binding and biomimetic cleavage of the RNA poly(U) by synthetic polyimidazolesCheng, Liang; Abhilash, K. G.; Breslow, RonaldProceedings of the National Academy of Sciences of the United States of America (2012), 109 (32), 12884-12887, S12884/1-S12884/5CODEN: PNASA6; ISSN:0027-8424. (National Academy of Sciences)Four polyimidazoles were used in the binding and cleavage studies with poly(U). The two polydisperse polyvinylimidazoles were previously described by others, while the other two new polymers of polyethyleneimines were prepd. by cationic polymn. of oxazolines. The latter had imidazole units attached to each nitrogen of the polymers. They were characterized by gel permeation chromatog. and had very low polydispersities. When they were partially protonated they bound to the poly(U) and catalyzed its cleavage by a process analogous to that used by the enzyme RNase A. The kinetics of the cleavage were followed by an assay we had previously described using phosphodiesterase I from Crotalus venom after the cleavage processes. Cleavage of poly(U) with Zn2+ was also examd., with and without the polymers. A scheme is described in which these cleavages could be made sequence selective with various RNAs, particularly with important targets, such as viral RNAs.
- 19Beloglazova, N. G.; Fabani, M. M.; Zenkova, M. A.; Bichenkova, E. V.; Polushin, N. N.; Sil’nikov, V. V.; Douglas, K. T.; Vlassov, V. V. Sequence-specific artificial ribonucleases. I. Bis -imidazole-containing oligonucleotide conjugates prepared using precursor-based strategy. Nucleic Acids Res. 2004, 32 (13), 3887– 3897, DOI: 10.1093/nar/gkh702[Crossref], [PubMed], [CAS], Google Scholar19https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD2cXmvFCjsLc%253D&md5=c81ecdfcbb5bdd2723a909e8aaaa3f36Sequence-specific artificial ribonucleases. I. Bis-imidazole-containing oligonucleotide conjugates prepared using precursor-based strategyBeloglazova, Natalia G.; Fabani, Martin M.; Zenkova, Marina A.; Bichenkova, Elena V.; Polushin, Nikolai N.; Sil'nikov, Vladimir V.; Douglas, Kenneth T.; Vlassov, Valentin V.Nucleic Acids Research (2004), 32 (13), 3887-3897CODEN: NARHAD; ISSN:0305-1048. (Oxford University Press)Antisense oligonucleotide conjugates, bearing constructs with two imidazole residues, were synthesized using a precursor-based technique employing post-synthetic histamine functionalization of oligonucleotides bearing methoxyoxalamido precursors at the 5'-termini. The conjugates were assessed in terms of their cleavage activities using both biochem. assays and conformational anal. by mol. modeling. The oligonucleotide part of the conjugates was complementary to the T-arm of yeast tRNAPhe (44-60 nt) and was expected to deliver imidazole groups near the fragile sequence C61-ACA-G65 of the tRNA. The conjugates showed RNase activity at neutral pH and physiol. temp. resulting in complete cleavage of the target RNA, mainly at the C63-A64 phosphodiester bond. For some constructs, cleavage was completed within 1-2 h under optimal conditions. Mol. modeling was used to det. the preferred orientation(s) of the cleaving group(s) in the complexes of the conjugates with RNA target. Cleaving constructs bearing two imidazole residues were found to be conformationally highly flexible, adopting no preferred specific conformation. No interactions other than complementary base pairing between the conjugates and the target were found to be the factors stabilizing the active cleaving conformation(s).
- 20Li, Z.-R.; Li, J.; Cai, W.; Lai, J. Y. H.; McKinnie, S. M. K.; Zhang, W.-P.; Moore, B. S.; Zhang, W.; Qian, P.-Y. Macrocyclic colibactin induces DNA double-strand breaks via copper-mediated oxidative cleavage. Nat. Chem. 2019, 11 (10), 880– 889, DOI: 10.1038/s41557-019-0317-7[Crossref], [PubMed], [CAS], Google Scholar20https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1MXhvVSkurvJ&md5=6c3a9fbfc5555f4a3387b39d3cdb2383Macrocyclic colibactin induces DNA double-strand breaks via copper-mediated oxidative cleavageLi, Zhong-Rui; Li, Jie; Cai, Wenlong; Lai, Jennifer Y. H.; McKinnie, Shaun M. K.; Zhang, Wei-Peng; Moore, Bradley S.; Zhang, Wenjun; Qian, Pei-YuanNature Chemistry (2019), 11 (10), 880-889CODEN: NCAHBB; ISSN:1755-4330. (Nature Research)Colibactin is an assumed human gut bacterial genotoxin, whose biosynthesis is linked to the clb genomic island that has a widespread distribution in pathogenic and commensal human enterobacteria. Colibactin-producing gut microbes promote colon tumor formation and enhance the progression of colorectal cancer via cellular senescence and death induced by DNA double-strand breaks (DSBs); however, the chem. basis that contributes to the pathogenesis at the mol. level has not been fully characterized. Here, the authors report the discovery of colibactin-645, a macrocyclic colibactin metabolite that recapitulates the previously assumed genotoxicity and cytotoxicity. Colibactin-645 shows strong DNA DSB activity in vitro and in human cell cultures via a unique copper-mediated oxidative mechanism. The authors also delineate a complete biosynthetic model for colibactin-645, which highlights a unique fate of the aminomalonate-building monomer in forming the C-terminal 5-hydroxy-4-oxazolecarboxylic acid moiety through the activities of both the polyketide synthase ClbO and the amidase ClbL. This work thus provides a mol. basis for colibactin's DNA DSB activity and facilitates further mechanistic study of colibactin-related colorectal cancer incidence and prevention.
- 21Peterson, J. R.; Thor, S.; Kohler, L.; Kohler, P. R. A.; Metcalf, W. W.; Luthey-Schulten, Z. Genome-wide gene expression and RNA half-life measurements allow predictions of regulation and metabolic behavior in Methanosarcina acetivorans. BMC Genomics 2016, 17, 924, DOI: 10.1186/s12864-016-3219-8[Crossref], [PubMed], [CAS], Google Scholar21https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1cXhtlWkur0%253D&md5=87bcf9df8a1aebb3c6b02978e0989738Genome-wide gene expression and RNA half-life measurements allow predictions of regulation and metabolic behavior in Methanosarcina acetivoransPeterson, Joseph R.; Thor, Sheng Shee; Kohler, Lars; Kohler, Petra R. A.; Metcalf, William W.; Luthey-Schulten, ZaidaBMC Genomics (2016), 17 (), 924/1-924/23CODEN: BGMEET; ISSN:1471-2164. (BioMed Central Ltd.)While a few studies on the variations in mRNA expression and half-lives measured under different growth conditions have been used to predict patterns of regulation in bacterial organisms, the extent to which this information can also play a role in defining metabolic phenotypes has yet to be examd. systematically. Here we present the first comprehensive study for a model methanogen. We use expression and half-life data for the methanogen Methanosarcina acetivorans growing on fast- and slow-growth substrates to examine the regulation of its genes. Unlike Escherichia coli where only small shifts in half-lives were obsd., we found that most mRNA have significantly longer half-lives for slow growth on acetate compared to fast growth on methanol or trimethylamine. Interestingly, half-life shifts are not uniform across functional classes of enzymes, suggesting the existence of a selective stabilization mechanism for mRNAs. Using the transcriptomics data we detd. whether transcription or degrdn. rate controls the change in transcript abundance. Degrdn. was found to control abundance for about half of the metabolic genes underscoring its role in regulating metab. Genes involved in half of the metabolic reactions were found to be differentially expressed among the substrates suggesting the existence of drastically different metabolic phenotypes that extend beyond just the methanogenesis pathways. By integrating expression data with an updated metabolic model of the organism (iST807) significant differences in pathway flux and prodn. of metabolites were predicted for the three growth substrates. This study provides the first global picture of differential expression and half-lives for a class II methanogen, as well as provides the first evidence in a single organism that drastic genome-wide shifts in RNA half-lives can be modulated by growth substrate. We detd. which genes in each metabolic pathway control the flux and classified them as regulated by transcription (e.g. transcription factor) or degrdn. (e.g. post-transcriptional modification). We found that more than half of genes in metab. were controlled by degrdn. Our results suggest that M. acetivorans employs extensive post-transcriptional regulation to optimize key metabolic steps, and more generally that degrdn. could play a much greater role in optimizing an organism's metab. than previously thought.
- 22Oivanen, M.; Kuusela, S.; Lönnberg, H. Kinetics and Mechanisms for the Cleavage and Isomerization of the Phosphodiester Bonds of RNA by Brønsted Acids and Bases. Chem. Rev. 1998, 98 (3), 961– 990, DOI: 10.1021/cr960425x[ACS Full Text
], [CAS], Google Scholar22https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaK1cXis1yqu7s%253D&md5=890374fb922f9ad0d2d871d264b63c9cKinetics and Mechanisms for the Cleavage and Isomerization of the Phosphodiester Bonds of RNA by Bronsted Acids and BasesOivanen, Mikko; Kuusela, Satu; Loennberg, HarriChemical Reviews (Washington, D. C.) (1998), 98 (3), 961-990CODEN: CHREAY; ISSN:0009-2665. (American Chemical Society)A review with 240 refs. on acid/base catalyzed cleavage and isomerization of the 3',5'-phosphodiester bonds of DNA. - 23Barbieri, I.; Tzelepis, K.; Pandolfini, L.; Shi, J.; Millán-Zambrano, G.; Robson, S. C.; Aspris, D.; Migliori, V.; Bannister, A. J.; Han, N.; De Braekeleer, E.; Ponstingl, H.; Hendrick, A.; Vakoc, C. R.; Vassiliou, G. S.; Kouzarides, T. Promoter-bound METTL3 maintains myeloid leukaemia by m6A-dependent translation control. Nature 2017, 552 (7683), 126– 131, DOI: 10.1038/nature24678[Crossref], [PubMed], [CAS], Google Scholar23https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2sXhvVynsb7N&md5=47c1daa65a18c808a4b0f6f31774fb45Promoter-bound METTL3 maintains myeloid leukaemia by m6A-dependent translation controlBarbieri, Isaia; Tzelepis, Konstantinos; Pandolfini, Luca; Shi, Junwei; Millan-Zambrano, Gonzalo; Robson, Samuel C.; Aspris, Demetrios; Migliori, Valentina; Bannister, Andrew J.; Han, Namshik; De Braekeleer, Etienne; Ponstingl, Hannes; Hendrick, Alan; Vakoc, Christopher R.; Vassiliou, George S.; Kouzarides, TonyNature (London, United Kingdom) (2017), 552 (7683), 126-131CODEN: NATUAS; ISSN:0028-0836. (Nature Research)N6-methyladenosine (m6A) is an abundant internal RNA modification in both coding and non-coding RNAs that is catalyzed by the METTL3-METTL14 methyltransferase complex. However, the specific role of these enzymes in cancer is still largely unknown. Here we define a pathway that is specific for METTL3 and is implicated in the maintenance of a leukemic state. We identify METTL3 as an essential gene for growth of acute myeloid leukemia cells in two distinct genetic screens. Downregulation of METTL3 results in cell cycle arrest, differentiation of leukemic cells and failure to establish leukemia in immunodeficient mice. We show that METTL3, independently of METTL14, assocs. with chromatin and localizes to the transcriptional start sites of active genes. The vast majority of these genes have the CAATT-box binding protein CEBPZ present at the transcriptional start site, and this is required for recruitment of METTL3 to chromatin. Promoter-bound METTL3 induces m6A modification within the coding region of the assocd. mRNA transcript, and enhances its translation by relieving ribosome stalling. We show that genes regulated by METTL3 in this way are necessary for acute myeloid leukemia. Together, these data define METTL3 as a regulator of a chromatin-based pathway that is necessary for maintenance of the leukemic state and identify this enzyme as a potential therapeutic target for acute myeloid leukemia.
- 24Vu, L. P.; Pickering, B. F.; Cheng, Y.; Zaccara, S.; Nguyen, D.; Minuesa, G.; Chou, T.; Chow, A.; Saletore, Y.; MacKay, M.; Schulman, J.; Famulare, C.; Patel, M.; Klimek, V. M.; Garrett-Bakelman, F. E.; Melnick, A.; Carroll, M.; Mason, C. E.; Jaffrey, S. R.; Kharas, M. G. The N6-methyladenosine m6A-forming enzyme METTL3 controls myeloid differentiation of normal hematopoietic and leukemia cells. Nat. Med. 2017, 23 (11), 1369– 1376, DOI: 10.1038/nm.4416[Crossref], [PubMed], [CAS], Google Scholar24https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2sXhsFSku7zM&md5=bbeed4ac8c2dee2baf3ec08e0dec630fThe N6-methyladenosine (m6A)-forming enzyme METTL3 controls myeloid differentiation of normal hematopoietic and leukemia cellsVu, Ly P.; Pickering, Brian F.; Cheng, Yuanming; Zaccara, Sara; Nguyen, Diu; Minuesa, Gerard; Chou, Timothy; Chow, Arthur; Saletore, Yogesh; MacKay, Matthew; Schulman, Jessica; Famulare, Christopher; Patel, Minal; Klimek, Virginia M.; Garrett-Bakelman, Francine E.; Melnick, Ari; Carroll, Martin; Mason, Christopher E.; Jaffrey, Samie R.; Kharas, Michael G.Nature Medicine (New York, NY, United States) (2017), 23 (11), 1369-1376CODEN: NAMEFI; ISSN:1078-8956. (Nature Research)N6-methyladenosine (m6A) is an abundant nucleotide modification in mRNA that is required for the differentiation of mouse embryonic stem cells. However, it remains unknown whether the m6A modification controls the differentiation of normal and/or malignant myeloid hematopoietic cells. Here we show that shRNA-mediated depletion of the m6A-forming enzyme METTL3 in human hematopoietic stem/progenitor cells (HSPCs) promotes cell differentiation, coupled with reduced cell proliferation. Conversely, overexpression of wild-type METTL3, but not of a catalytically inactive form of METTL3, inhibits cell differentiation and increases cell growth. METTL3 mRNA and protein are expressed more abundantly in acute myeloid leukemia (AML) cells than in healthy HSPCs or other types of tumor cells. Furthermore, METTL3 depletion in human myeloid leukemia cell lines induces cell differentiation and apoptosis and delays leukemia progression in recipient mice in vivo. Single-nucleotide-resoln. mapping of m6A coupled with ribosome profiling reveals that m6A promotes the translation of c-MYC, BCL2 and PTEN mRNAs in the human acute myeloid leukemia MOLM-13 cell line. Moreover, loss of METTL3 leads to increased levels of phosphorylated AKT, which contributes to the differentiation-promoting effects of METTL3 depletion. Overall, these results provide a rationale for the therapeutic targeting of METTL3 in myeloid leukemia.
- 25Pendleton, K. E.; Chen, B.; Liu, K.; Hunter, O. V.; Xie, Y.; Tu, B. P.; Conrad, N. K. The U6 snRNA m6A Methyltransferase METTL16 Regulates SAM Synthetase Intron Retention. Cell 2017, 169 (5), 824– 835, DOI: 10.1016/j.cell.2017.05.003[Crossref], [PubMed], [CAS], Google Scholar25https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2sXotlOqtr4%253D&md5=e18b9d1155f4db389d87875a48d50dd6The U6 snRNA m6A methyltransferase METTL16 regulates SAM synthetase intron retentionPendleton, Kathryn E.; Chen, Beibei; Liu, Kuanqing; Hunter, Olga V.; Xie, Yang; Tu, Benjamin P.; Conrad, Nicholas K.Cell (Cambridge, MA, United States) (2017), 169 (5), 824-835.e14CODEN: CELLB5; ISSN:0092-8674. (Cell Press)Maintenance of proper levels of the Me donor S-adenosylmethionine (SAM) is crit. for a wide variety of biol. processes. We demonstrate that the N6-adenosine methyltransferase METTL16 regulates expression of human MAT2A, which encodes the SAM synthetase expressed in most cells. Upon SAM depletion by methionine starvation, cells induce MAT2A expression by enhanced splicing of a retained intron. Induction requires METTL16 and its methylation substrate, a vertebrate conserved hairpin (hp1) in the MAT2A 3' UTR. Increasing METTL16 occupancy on the MAT2A 3' UTR is sufficient to induce efficient splicing. We propose that, under SAM-limiting conditions, METTL16 occupancy on hp1 increases due to inefficient enzymic turnover, which promotes MAT2A splicing. We further show that METTL16 is the long-unknown methyltransferase for the U6 spliceosomal small nuclear RNA (snRNA). These observations suggest that the conserved U6 snRNA methyltransferase evolved an addnl. function in vertebrates to regulate SAM homeostasis.
- 26Bokar, J. A.; Shambaugh, M. E.; Polayes, D.; Matera, A. G.; Rottman, F. M. Purification and cDNA cloning of the AdoMet-binding subunit of the human mRNA (N6-adenosine)-methyltransferase. RNA 1997, 3 (11), 1233– 1247[PubMed], [CAS], Google Scholar26https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaK2sXnsVelsL0%253D&md5=b1733d1237a94608508cfe7e86fb7e6dPurification and cDNA cloning of the AdoMet-binding subunit of the human mRNA (N6-adenosine)-methyltransferaseBokar, Joseph A.; Shambaugh, Mary Eileen; Polayes, Deborah; Matera, A. Gregory; Rottman, Fritz M.RNA (1997), 3 (11), 1233-1247CODEN: RNARFU; ISSN:1355-8382. (Cambridge University Press)The methylation of internal adenosine residues in eukaryotic mRNA, forming N6-methyladenosine (m6A), is catalyzed by a complex multicomponent enzyme. Previous studies suggested that m6A affects the efficiency of mRNA processing or transport, although the mechanism by which this occurs is not known. As a step toward better understanding the mechanism and function of this ubiquitous posttranscriptional modification, the authors have shown that HeLa mRNA (N6-adenosine)-methyltransferase requires at least two sep. protein factors, MT-A and MT-B, and MT-A contains the AdoMet binding site on a 70-kDa subunit (MT-A70). MT-A70 was purified by conventional chromatog. and electrophoresis, and was microsequenced. The peptide sequence was used to design a degenerate oligodeoxynucleotide that in turn was used to isolate the cDNA clone coding for MT-A70 from a HeLa cDNA library. Recombinant MT-A70 was expressed as a fusion protein in bacteria and was used to generate anti-MT-A70 antisera in rabbits. These antisera recognize MT-A70 in HeLa nuclear exts. by western blot and are capable of depleting (N6-adenosine)-methyltransferase activity from HeLa nuclear ext., confirming that MT-A70 is a crit. subunit of (N6-adenosine)-methyltransferase. Northern blot anal. reveals that MT-A70 mRNA is present in a wide variety of human tissues and may undergo alternative splicing. MT-A70 cDNA probe hybridizes to a 2.0-kilobase (kb) polyadenylated RNA isolated from HeLa cells, whereas it hybridizes to two predominant RNA species (approx. 2.0 kb and 3.0 kb) using mRNA isolated from six different human tissues. Anal. of the cDNA sequence indicates that it codes for a 580-amino acid protein with a predicted MW = 65 kDa. The predicted protein contains sequences similar to consensus methylation motifs I and II identified in prokaryotic DNA (N6-adenosine)-methyltransferases, suggesting the functional conservation of peptide motifs. MT-A70 also contains a long region of homol. to the yeast protein SPO8, which is involved in induction of sporulation by an unknown mechanism.
- 27Wiederschain, D.; Wee, S.; Chen, L.; Loo, A.; Yang, G.; Huang, A.; Chen, Y.; Caponigro, G.; Yao, Y.-M.; Lengauer, C.; Sellers, W. R.; Benson, J. D. Single-vector inducible lentiviral RNAi system for oncology target validation. Cell Cycle 2009, 8 (3), 498– 504, DOI: 10.4161/cc.8.3.7701[Crossref], [PubMed], [CAS], Google Scholar27https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD1MXlvFWjtrs%253D&md5=5361e51d2b0e18a834453984bc4667f2Single-vector inducible lentiviral RNAi system for oncology target validationWiederschain, Dmitri; Wee, Susan; Chen, Lin; Loo, Alice; Yang, Guizhi; Huang, Alan; Chen, Yan; Caponigro, Giordano; Yao, Yung-mae; Lengauer, Christoph; Sellers, William R.; Benson, John D.Cell Cycle (2009), 8 (3), 498-504CODEN: CCEYAS; ISSN:1538-4101. (Landes Bioscience)The use of RNA interference (RNAi) has enabled loss-of-function studies in mammalian cancer cells and has hence become crit. for identifying and validating cancer drug targets. Current transient siRNA and stable shRNA systems, however, have limited utility in accurately assessing the cancer dependency due to their short-lived effects and limited in vivo utility, resp. In this study, a single-vector lentiviral, Tet-inducible shRNA system (pLKO-Tet-On) was generated to allow for the rapid generation of multiple stable cell lines with regulatable shRNA expression. We demonstrate the advantages and versatility of this system by targeting two polycomb group proteins, Bmi-1 and Mel-18, in a no. of cancer cell lines. Our data show that pLKO-Tet-On-mediated knockdown is tightly regulated by the inducer tetracycline and its deriv., doxycycline, in a concn.- and time-dependent manner. Furthermore, target gene expression is fully restored upon withdrawal of the inducing agent. An addnl., 17 distinct gene products have been targeted by inducible shRNAs with robust regulation in all cases. Importantly, we functionally validate the ability of the pLKO-Tet-On vector to reversibly silence targeted transcripts in vivo. The versatile and robust inducible lentiviral RNAi system reported herein can therefore serve as a powerful tool to rapidly reveal tumor cell dependence.
- 28Leger, A.; Amaral, P. P.; Pandolfini, L.; Capitanchik, C.; Capraro, F.; Barbieri, I.; Migliori, V.; Luscombe, N. M.; Enright, A. J.; Tzelepis, K.; Ule, J.; Fitzgerald, T.; Birney, E.; Leonardi, T.; Kouzarides, T. RNA modifications detection by comparative Nanopore direct RNA sequencing. bioRxiv 2019, 843136, https://www.biorxiv.org/content/10.1101/843136v1.Google ScholarThere is no corresponding record for this reference.
- 29Doxtader, K. A.; Wang, P.; Scarborough, A. M.; Seo, D.; Conrad, N. K.; Nam, Y. Structural Basis for Regulation of METTL16, an S-Adenosylmethionine Homeostasis Factor. Mol. Cell 2018, 71 (6), 1001– 1011, DOI: 10.1016/j.molcel.2018.07.025[Crossref], [PubMed], [CAS], Google Scholar29https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1cXhs1Kkt7vF&md5=38e7677ae6ccc47726b00d0c795e2e04Structural Basis for Regulation of METTL16, an S-Adenosylmethionine Homeostasis FactorDoxtader, Katelyn A.; Wang, Ping; Scarborough, Anna M.; Seo, Dahee; Conrad, Nicholas K.; Nam, YunsunMolecular Cell (2018), 71 (6), 1001-1011.e4CODEN: MOCEFL; ISSN:1097-2765. (Elsevier Inc.)S-adenosylmethionine (SAM) is an essential metabolite that acts as a cofactor for most methylation events in the cell. The N6-methyladenosine (m6A) methyltransferase METTL16 controls SAM homeostasis by regulating the abundance of SAM synthetase MAT2A mRNA in response to changing intracellular SAM levels. Here we present crystal structures of METTL16 in complex with MAT2A RNA hairpins to uncover crit. mol. mechanisms underlying the regulated activity of METTL16. The METTL16-RNA complex structures reveal at. details of RNA substrates that drive productive methylation by METTL16. In addn., we identify a polypeptide loop in METTL16 near the SAM binding site with an autoregulatory role. We show that mutations that enhance or repress METTL16 activity in vitro correlate with changes in MAT2A mRNA levels in cells. Thus, we demonstrate the structural basis for the specific activity of METTL16 and further suggest the mol. mechanisms by which METTL16 efficiency is tuned to regulate SAM homeostasis.
- 30Yang, D.; Qiao, J.; Wang, G.; Lan, Y.; Li, G.; Guo, X.; Xi, J.; Ye, D.; Zhu, S.; Chen, W.; Jia, W.; Leng, Y.; Wan, X.; Kang, J. N6-Methyladenosine modification of lincRNA 1281 is critically required for mESC differentiation potential. Nucleic Acids Res. 2018, 46 (8), 3906– 3920, DOI: 10.1093/nar/gky130[Crossref], [PubMed], [CAS], Google Scholar30https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1cXitlKhtbnL&md5=507b077d7afa2d0c60c8e2659592fab4N6-methyladenosine modification of lincRNA 1281 is critically required for mESC differentiation potentialYang, Dandan; Qiao, Jing; Wang, Guiying; Lan, Yuanyuan; Li, Guoping; Guo, Xudong; Xi, Jiajie; Ye, Dan; Zhu, Songcheng; Chen, Wen; Jia, Wenwen; Leng, Ye; Wan, Xiaoping; Kang, JiuhongNucleic Acids Research (2018), 46 (8), 3906-3920CODEN: NARHAD; ISSN:1362-4962. (Oxford University Press)Previous studies have revealed the crit. roles of N6-methyladenosine (m6A) modification of mRNA in embryonic stem cells (ESCs), but the biol. function of m6A in large intergenic noncoding RNA (lincRNA) is unknown. Here, we showed that the internal m6A modification of linc1281 mediates a competing endogenous RNA (ceRNA) model to regulate mouse ESC (mESC) differentiation. We demonstrated that loss of linc1281 compromises mESC differentiation and that m6A is highly enriched within linc1281 transcripts. Linc1281 with RRACU m6A sequence motifs, but not an m6A-deficient mutant, restored the phenotype in linc1281-depleted mESCs. Mechanistic analyses revealed that linc1281 ensures mESC identity by sequestering pluripotency-related let-7 family microRNAs (miRNAs), and this RNA-RNA interaction is m6A dependent. Collectively, these findings elucidated the functional roles of linc1281 and its m6A modification in mESCs and identified a novel RNA regulatory mechanism, providing a basis for further exploration of broad RNA epigenetic regulatory patterns.
- 31Zhang, J.; Guo, S.; Piao, H.-Y.; Wang, Y.; Wu, Y.; Meng, X.-Y.; Yang, D.; Zheng, Z.-C.; Zhao, Y. ALKBH5 promotes invasion and metastasis of gastric cancer by decreasing methylation of the lncRNA NEAT1. J. Physiol. Biochem. 2019, 75 (3), 379– 389, DOI: 10.1007/s13105-019-00690-8[Crossref], [PubMed], [CAS], Google Scholar31https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1MXhtlGktbrN&md5=ecab4a9cdbb68eaa311e72fc36471f7dALKBH5 promotes invasion and metastasis of gastric cancer by decreasing methylation of the lncRNA NEAT1Zhang, Jun; Guo, Shuai; Piao, Hai-yan; Wang, Yue; Wu, Yue; Meng, Xiang-yu; Yang, Dong; Zheng, Zhi-chao; Zhao, YanJournal of Physiology and Biochemistry (2019), 75 (3), 379-389CODEN: JPBIF2; ISSN:1138-7548. (Springer)N6-Methyladenosine (m6A) is the most common posttranscriptional modification of RNA and plays crit. roles in cancer pathogenesis. However, the biol. function of long noncoding RNA (lncRNA) methylation remains unclear. As a demethylase, ALKBH5 (alkylation repair homolog protein 5) is involved in mediating methylation reversal. The purpose of this study was to investigate lncRNA m6A modification and its role in gastric cancer (GC). Bioinformatics predicted interactions of ALKBH5 with lncRNAs. Five methods were employed to assess the function of nuclear paraspeckle assembly transcript 1 (NEAT1), including gene silencing, RT-PCR, sepn. of nuclear and cytoplasmic fractions, scrape motility assays, and transwell migration assays. Then, m6A RNA immunopptn. and immunofluorescence were used to detect methylated NEAT1 in GC cells. Rescue assays were performed to define the relationship between NEAT1 and ALKBH5. NEAT1 is a potential binding lncRNA of ALKBH5. NEAT1 was overexpressed in GC cells and tissue. Addnl. expts. confirmed that knockdown of NEAT1 significantly repressed invasion and metastasis of GC cells. ALKBH5 affected the m6A level of NEAT1. The binding of ALKBH5 and NEAT1 influences the expression of EZH2 (a subunit of the polycomb repressive complex) and thus affects GC invasion and metastasis. Our findings indicate a novel mechanism by which ALKBH5 promotes GC invasion and metastasis by demethylating the lncRNA NEAT1. They may be potential therapeutic targets for GC.
- 32Zhou, K. I.; Parisien, M.; Dai, Q.; Liu, N.; Diatchenko, L.; Sachleben, J. R.; Pan, T. N6-Methyladenosine Modification in a Long Noncoding RNA Hairpin Predisposes Its Conformation to Protein Binding. J. Mol. Biol. 2016, 428, 822– 833, DOI: 10.1016/j.jmb.2015.08.021[Crossref], [PubMed], [CAS], Google Scholar32https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2MXhsV2ntr7J&md5=51fd64645634b0f56b234e083f5e5411N6-Methyladenosine Modification in a Long Noncoding RNA Hairpin Predisposes Its Conformation to Protein BindingZhou, Katherine I.; Parisien, Marc; Dai, Qing; Liu, Nian; Diatchenko, Luda; Sachleben, Joseph R.; Pan, TaoJournal of Molecular Biology (2016), 428 (5_Part_A), 822-833CODEN: JMOBAK; ISSN:0022-2836. (Elsevier Ltd.)N6-Methyladenosine (m6A) is a reversible and abundant internal modification of mRNA and long noncoding RNA (lncRNA) with roles in RNA processing, transport, and stability. Although m6A does not preclude Watson-Crick base pairing, the N6-Me group alters the stability of RNA secondary structure. Since changes in RNA structure can affect diverse cellular processes, the influence of m6A on mRNA and lncRNA structure has the potential to be an important mechanism for m6A function in the cell. Indeed, an m6A site in the lncRNA metastasis assocd. lung adenocarcinoma transcript 1 (MALAT1) was recently shown to induce a local change in structure that increases the accessibility of a U5-tract for recognition and binding by heterogeneous nuclear ribonucleoprotein C (HNRNPC). This m6A-dependent regulation of protein binding through a change in RNA structure, termed "m6A-switch", affects transcriptome-wide mRNA abundance and alternative splicing. To further characterize this first example of an m6A-switch in a cellular RNA, we used NMR and Forester resonance energy transfer to demonstrate the effect of m6A on a 32-nucleotide RNA hairpin derived from the m6A-switch in MALAT1. The obsd. imino proton NMR resonances and Forester resonance energy transfer efficiencies suggest that m6A selectively destabilizes the portion of the hairpin stem where the U5-tract is located, increasing the solvent accessibility of the neighboring bases while maintaining the overall hairpin structure. The m6A-modified hairpin has a predisposed conformation that resembles the hairpin conformation in the RNA-HNRNPC complex more closely than the unmodified hairpin. The m6A-induced structural changes in the MALAT1 hairpin can serve as a model for a large family of m6A-switches that mediate the influence of m6A on cellular processes.
- 33Huang, H.; Weng, H.; Zhou, K.; Wu, T.; Zhao, B. S.; Sun, M.; Chen, Z.; Deng, X.; Xiao, G.; Auer, F.; Klemm, L.; Wu, H.; Zuo, Z.; Qin, X.; Dong, Y.; Zhou, Y.; Qin, H.; Tao, S.; Du, J.; Liu, J.; Lu, Z.; Yin, H.; Mesquita, A.; Yuan, C. L.; Hu, Y.-C.; Sun, W.; Su, R.; Dong, L.; Shen, C.; Li, C.; Qing, Y.; Jiang, X.; Wu, X.; Sun, M.; Guan, J.-L.; Qu, L.; Wei, M.; Müschen, M.; Huang, G.; He, C.; Yang, J.; Chen, J. Histone H3 trimethylation at lysine 36 guides m6A RNA modification co-transcriptionally. Nature 2019, 567 (7748), 414– 419, DOI: 10.1038/s41586-019-1016-7[Crossref], [PubMed], [CAS], Google Scholar33https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1MXmslKhurg%253D&md5=11437346726aee249c9cf8782eb4f42fHistone H3 trimethylation at lysine 36 guides m6A RNA modification co-transcriptionallyHuang, Huilin; Weng, Hengyou; Zhou, Keren; Wu, Tong; Zhao, Boxuan Simen; Sun, Mingli; Chen, Zhenhua; Deng, Xiaolan; Xiao, Gang; Auer, Franziska; Klemm, Lars; Wu, Huizhe; Zuo, Zhixiang; Qin, Xi; Dong, Yunzhu; Zhou, Yile; Qin, Hanjun; Tao, Shu; Du, Juan; Liu, Jun; Lu, Zhike; Yin, Hang; Mesquita, Ana; Yuan, Celvie L.; Hu, Yueh-Chiang; Sun, Wenju; Su, Rui; Dong, Lei; Shen, Chao; Li, Chenying; Qing, Ying; Jiang, Xi; Wu, Xiwei; Sun, Miao; Guan, Jun-Lin; Qu, Lianghu; Wei, Minjie; Muschen, Markus; Huang, Gang; He, Chuan; Yang, Jianhua; Chen, JianjunNature (London, United Kingdom) (2019), 567 (7748), 414-419CODEN: NATUAS; ISSN:0028-0836. (Nature Research)DNA and histone modifications have notable effects on gene expression1. Being the most prevalent internal modification in mRNA, the N6-methyladenosine (m6A) mRNA modification is as an important post-transcriptional mechanism of gene regulation2-4 and has crucial roles in various normal and pathol. processes5-12. However, it is unclear how m6A is specifically and dynamically deposited in the transcriptome. Here we report that histone H3 trimethylation at Lys36 (H3K36me3), a marker for transcription elongation, guides m6A deposition globally. We show that m6A modifications are enriched in the vicinity of H3K36me3 peaks, and are reduced globally when cellular H3K36me3 is depleted. Mechanistically, H3K36me3 is recognized and bound directly by METTL14, a crucial component of the m6A methyltransferase complex (MTC), which in turn facilitates the binding of the m6A MTC to adjacent RNA polymerase II, thereby delivering the m6A MTC to actively transcribed nascent RNAs to deposit m6A co-transcriptionally. In mouse embryonic stem cells, phenocopying METTL14 knockdown, H3K36me3 depletion also markedly reduces m6A abundance transcriptome-wide and in pluripotency transcripts, resulting in increased cell stemness. Collectively, our studies reveal the important roles of H3K36me3 and METTL14 in detg. specific and dynamic deposition of m6A in mRNA, and uncover another layer of gene expression regulation that involves crosstalk between histone modification and RNA methylation.
- 34Liu, J.; Dou, X.; Chen, C.; Chen, C.; Liu, C.; Xu, M. M.; Zhao, S.; Shen, B.; Gao, Y.; Han, D.; He, C. N6-methyladenosine of chromosome-associated regulatory RNA regulates chromatin state and transcription. Science 2020, 367 (6477), 580– 586, DOI: 10.1126/science.aay6018[Crossref], [PubMed], [CAS], Google Scholar34https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BB3cXitVGiurw%253D&md5=e2a4f15c7c401604e94665c93960cd01N6-methyladenosine of chromosome-associated regulatory RNA regulates chromatin state and transcriptionLiu, Jun; Dou, Xiaoyang; Chen, Chuanyuan; Chen, Chuan; Liu, Chang; Xu, Meng Michelle; Zhao, Siqi; Shen, Bin; Gao, Yawei; Han, Dali; He, ChuanScience (Washington, DC, United States) (2020), 367 (6477), 580-586CODEN: SCIEAS; ISSN:1095-9203. (American Association for the Advancement of Science)N6-methyladenosine (m6A) regulates stability and translation of mRNA in various biol. processes. In this work, we show that knockout of the m6A writer Mettl3 or the nuclear reader Ythdc1 in mouse embryonic stem cells increases chromatin accessibility and activates transcription in an m6A-dependent manner. We found that METTL3 deposits m6A modifications on chromosome-assocd. regulatory RNAs (carRNAs), including promoter-assocd. RNAs, enhancer RNAs, and repeat RNAs. YTHDC1 facilitates the decay of a subset of these m6A-modified RNAs, esp. elements of the long interspersed element-1 family, through the nuclear exosome targeting-mediated nuclear degrdn. Reducing m6A methylation by METTL3 depletion or site-specific m6A demethylation of selected carRNAs elevates the levels of carRNAs and promotes open chromatin state and downstream transcription. Collectively, our results reveal that m6A on carRNAs can globally tune chromatin state and transcription.
- 35Louloupi, A.; Ntini, E.; Conrad, T.; Ørom, U. A. V. Transient N6-Methyladenosine Transcriptome Sequencing Reveals a Regulatory Role of m6A in Splicing Efficiency. Cell Rep. 2018, 23 (12), 3429– 3437, DOI: 10.1016/j.celrep.2018.05.077[Crossref], [PubMed], [CAS], Google Scholar35https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1cXhtFOkur7M&md5=de3849159013bacdaa2f1b16598fcb9fTransient N-6-Methyladenosine Transcriptome Sequencing Reveals a Regulatory Role of m6A in Splicing EfficiencyLouloupi, Annita; Ntini, Evgenia; Conrad, Thomas; Oerom, Ulf Andersson VangCell Reports (2018), 23 (12), 3429-3437CODEN: CREED8; ISSN:2211-1247. (Cell Press)Splicing efficiency varies among transcripts, and tight control of splicing kinetics is crucial for coordinated gene expression. N-6-methyladenosine (m6A) is the most abundant RNA modification and is involved in regulation of RNA biogenesis and function. The impact of m6A on regulation of RNA splicing kinetics is unknown. Here, we provide a time-resolved high-resoln. assessment of m6A on nascent RNA transcripts and unveil its importance for the control of RNA splicing kinetics. We find that early co-transcriptional m6A deposition near splice junctions promotes fast splicing, while m6A modifications in introns are assocd. with long, slowly processed introns and alternative splicing events. In conclusion, we show that early m6A deposition specifies the fate of transcripts regarding splicing kinetics and alternative splicing.
- 36Mendel, M.; Chen, K.-M.; Homolka, D.; Gos, P.; Pandey, R. R.; McCarthy, A. A.; Pillai, R. S. Methylation of Structured RNA by the m6A Writer METTL16 Is Essential for Mouse Embryonic Development. Mol. Cell 2018, 71 (6), 986– 1000, DOI: 10.1016/j.molcel.2018.08.004[Crossref], [PubMed], [CAS], Google Scholar36https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1cXhs1Kkt7jK&md5=8d5b3d90ae43944528e1bbb87a0e1e14Methylation of Structured RNA by the m6A Writer METTL16 Is Essential for Mouse Embryonic DevelopmentMendel, Mateusz; Chen, Kuan-Ming; Homolka, David; Gos, Pascal; Pandey, Radha Raman; McCarthy, Andrew A.; Pillai, Ramesh S.Molecular Cell (2018), 71 (6), 986-1000.e11CODEN: MOCEFL; ISSN:1097-2765. (Elsevier Inc.)Internal modification of RNAs with N6-methyladenosine (m6A) is a highly conserved means of gene expression control. While the METTL3/METTL14 heterodimer adds this mark on thousands of transcripts in a single-stranded context, the substrate requirements and physiol. roles of the second m6A writer METTL16 remain unknown. Here we describe the crystal structure of human METTL16 to reveal a methyltransferase domain furnished with an extra N-terminal module, which together form a deep-cut groove that is essential for RNA binding. When presented with a random pool of RNAs, METTL16 selects for methylation-structured RNAs where the crit. adenosine is present in a bulge. Mouse 16-cell embryos lacking Mettl16 display reduced mRNA levels of its methylation target, the SAM synthetase Mat2a. The consequence is massive transcriptome dysregulation in ∼64-cell blastocysts that are unfit for further development. This highlights the role of an m6A RNA methyltransferase in facilitating early development via regulation of SAM availability.
- 37Shima, H.; Matsumoto, M.; Ishigami, Y.; Ebina, M.; Muto, A.; Sato, Y.; Kumagai, S.; Ochiai, K.; Suzuki, T.; Igarashi, K. S-Adenosylmethionine Synthesis Is Regulated by Selective N6-Adenosine Methylation and mRNA Degradation Involving METTL16 and YTHDC1. Cell Rep. 2017, 21 (12), 3354– 3363, DOI: 10.1016/j.celrep.2017.11.092[Crossref], [PubMed], [CAS], Google Scholar37https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2sXitVWlsrbE&md5=95ed079e22ae359a395b3d11d58a494bS-Adenosylmethionine Synthesis Is Regulated by Selective N6-Adenosine Methylation and mRNA Degradation Involving METTL16 and YTHDC1Shima, Hiroki; Matsumoto, Mitsuyo; Ishigami, Yuma; Ebina, Masayuki; Muto, Akihiko; Sato, Yuho; Kumagai, Sayaka; Ochiai, Kyoko; Suzuki, Tsutomu; Igarashi, KazuhikoCell Reports (2017), 21 (12), 3354-3363CODEN: CREED8; ISSN:2211-1247. (Cell Press)S-adenosylmethionine (SAM) is an important metabolite as a methyl-group donor in DNA and histone methylation, tuning regulation of gene expression. Appropriate intracellular SAM levels must be maintained, because methyltransferase reaction rates can be limited by SAM availability. In response to SAM depletion, MAT2A, which encodes a ubiquitous mammalian methionine adenosyltransferase isoenzyme, was upregulated through mRNA stabilization. SAM-depletion reduced N6-methyladenosine (m6A) in the 3' UTR of MAT2A. In vitro reactions using recombinant METTL16 revealed multiple, conserved methylation targets in the 3' UTR. Knockdown of METTL16 and the m6A reader YTHDC1 abolished SAM-responsive regulation of MAT2A. Mutations of the target adenine sites of METTL16 within the 3' UTR revealed that these m6As were redundantly required for regulation. MAT2A mRNA methylation by METTL16 is read by YTHDC1, and we suggest that this allows cells to monitor and maintain intracellular SAM levels.
- 38Zhang, L.-S.; Liu, C.; Ma, H.; Dai, Q.; Sun, H.-L.; Luo, G.; Zhang, Z.; Zhang, L.; Hu, L.; Dong, X.; He, C. Transcriptome-wide Mapping of Internal N7-Methylguanosine Methylome in Mammalian mRNA. Mol. Cell 2019, 74 (6), 1304– 1316, DOI: 10.1016/j.molcel.2019.03.036[Crossref], [PubMed], [CAS], Google Scholar38https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1MXosVSgtbs%253D&md5=7031c6e2fa681366856d66a9a843c7f8Transcriptome-wide Mapping of Internal N7-Methylguanosine Methylome in Mammalian mRNAZhang, Li-Sheng; Liu, Chang; Ma, Honghui; Dai, Qing; Sun, Hui-Lung; Luo, Guanzheng; Zhang, Zijie; Zhang, Linda; Hu, Lulu; Dong, Xueyang; He, ChuanMolecular Cell (2019), 74 (6), 1304-1316.e8CODEN: MOCEFL; ISSN:1097-2765. (Elsevier Inc.)N7-methylguanosine (m7G) is a pos. charged, essential modification at the 5' cap of eukaryotic mRNA, regulating mRNA export, translation, and splicing. M7G also occurs internally within tRNA and rRNA, but its existence and distribution within eukaryotic mRNA remain to be investigated. Here, we show the presence of internal m7G sites within mammalian mRNA. We then performed transcriptome-wide profiling of internal m7G methylome using m7G-MeRIP sequencing (MeRIP-seq). To map this modification at base resoln., we developed a chem.-assisted sequencing approach that selectively converts internal m7G sites into abasic sites, inducing misincorporation at these sites during reverse transcription. This base-resoln. m7G-seq enabled transcriptome-wide mapping of m7G in human tRNA and mRNA, revealing distribution features of the internal m7G methylome in human cells. We also identified METTL1 as a methyltransferase that installs a subset of m7G within mRNA and showed that internal m7G methylation could affect mRNA translation.
- 39Lee, S.-H.; Singh, I.; Tisdale, S.; Abdel-Wahab, O.; Leslie, C. S.; Mayr, C. Widespread intronic polyadenylation inactivates tumour suppressor genes in leukaemia. Nature 2018, 561 (7721), 127– 131, DOI: 10.1038/s41586-018-0465-8[Crossref], [PubMed], [CAS], Google Scholar39https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1cXhsF2nsrjJ&md5=cb45b01f216beec2c3d75e3514f74721Widespread intronic polyadenylation inactivates tumour suppressor genes in leukemiaLee, Shih-Han; Singh, Irtisha; Tisdale, Sarah; Abdel-Wahab, Omar; Leslie, Christina S.; Mayr, ChristineNature (London, United Kingdom) (2018), 561 (7721), 127-131CODEN: NATUAS; ISSN:0028-0836. (Nature Research)DNA mutations are known cancer drivers. Here we investigated whether mRNA events that are upregulated in cancer can functionally mimic the outcome of genetic alterations. RNA sequencing or 3'-end sequencing techniques were applied to normal and malignant B cells from 59 patients with chronic lymphocytic leukemia (CLL)1-3. We discovered widespread upregulation of truncated mRNAs and proteins in primary CLL cells that were not generated by genetic alterations but instead occurred by intronic polyadenylation. Truncated mRNAs caused by intronic polyadenylation were recurrent (n = 330) and predominantly affected genes with tumor-suppressive functions. The truncated proteins generated by intronic polyadenylation often lack the tumor-suppressive functions of the corresponding full-length proteins (such as DICER and FOXN3), and several even acted in an oncogenic manner (such as CARD11, MGA and CHST11). In CLL, the inactivation of tumor-suppressor genes by aberrant mRNA processing is substantially more prevalent than the functional loss of such genes through genetic events. We further identified new candidate tumor-suppressor genes that are inactivated by intronic polyadenylation in leukemia and by truncating DNA mutations in solid tumors4,5. These genes are understudied in cancer, as their overall mutation rates are lower than those of well-known tumor-suppressor genes. Our findings show the need to go beyond genomic analyses in cancer diagnostics, as mRNA events that are silent at the DNA level are widespread contributors to cancer pathogenesis through the inactivation of tumor-suppressor genes.
- 40Singh, I.; Lee, S.-H.; Sperling, A. S.; Samur, M. K.; Tai, Y.-T.; Fulciniti, M.; Munshi, N. C.; Mayr, C.; Leslie, C. S. Widespread intronic polyadenylation diversifies immune cell transcriptomes. Nat. Commun. 2018, 9 (1), 1716, DOI: 10.1038/s41467-018-04112-z[Crossref], [PubMed], [CAS], Google Scholar40https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A280%3ADC%252BC1MjosVCguw%253D%253D&md5=b5e11fe75fbd9eb1011a636dc31ec3d5Widespread intronic polyadenylation diversifies immune cell transcriptomesSingh Irtisha; Leslie Christina S; Singh Irtisha; Lee Shih-Han; Mayr Christine; Sperling Adam S; Samur Mehmet K; Tai Yu-Tzu; Fulciniti Mariateresa; Munshi Nikhil CNature communications (2018), 9 (1), 1716 ISSN:.Alternative cleavage and polyadenylation (ApA) is known to alter untranslated region (3'UTR) length but can also recognize intronic polyadenylation (IpA) signals to generate transcripts that lose part or all of the coding region. We analyzed 46 3'-seq and RNA-seq profiles from normal human tissues, primary immune cells, and multiple myeloma (MM) samples and created an atlas of 4927 high-confidence IpA events represented in these cell types. IpA isoforms are widely expressed in immune cells, differentially used during B-cell development or in different cellular environments, and can generate truncated proteins lacking C-terminal functional domains. This can mimic ectodomain shedding through loss of transmembrane domains or alter the binding specificity of proteins with DNA-binding or protein-protein interaction domains. MM cells display a striking loss of IpA isoforms expressed in plasma cells, associated with shorter progression-free survival and impacting key genes in MM biology and response to lenalidomide.
- 41Jung, H.; Lee, D.; Lee, J.; Park, D.; Kim, Y. J.; Park, W.-Y.; Hong, D.; Park, P. J.; Lee, E. Intron retention is a widespread mechanism of tumor-suppressor inactivation. Nat. Genet. 2015, 47 (11), 1242– 1248, DOI: 10.1038/ng.3414[Crossref], [PubMed], [CAS], Google Scholar41https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2MXhs1Wls7nE&md5=3066f0d5ad036a5219f0fe69703b9c86Intron retention is a widespread mechanism of tumor-suppressor inactivationJung, Hyunchul; Lee, Donghoon; Lee, Jongkeun; Park, Donghyun; Kim, Yeon Jeong; Park, Woong-Yang; Hong, Dongwan; Park, Peter J.; Lee, EunjungNature Genetics (2015), 47 (11), 1242-1248CODEN: NGENEC; ISSN:1061-4036. (Nature Publishing Group)A substantial fraction of disease-causing mutations are pathogenic through aberrant splicing. Although genome profiling studies have identified somatic single-nucleotide variants (SNVs) in cancer, the extent to which these variants trigger abnormal splicing has not been systematically examd. Here we analyzed RNA sequencing and exome data from 1,812 patients with cancer and identified ∼900 somatic exonic SNVs that disrupt splicing. At least 163 SNVs, including 31 synonymous ones, were shown to cause intron retention or exon skipping in an allele-specific manner, with ∼70% of the SNVs occurring on the last base of exons. Notably, SNVs causing intron retention were enriched in tumor suppressors, and 97% of these SNVs generated a premature termination codon, leading to loss of function through nonsense-mediated decay or truncated protein. We also characterized the genomic features predictive of such splicing defects. Overall, this work demonstrates that intron retention is a common mechanism of tumor-suppressor inactivation.
- 42Kopp, F.; Mendell, J. T. Functional Classification and Experimental Dissection of Long Noncoding RNAs. Cell 2018, 172 (3), 393– 407, DOI: 10.1016/j.cell.2018.01.011[Crossref], [PubMed], [CAS], Google Scholar42https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1cXislyisLc%253D&md5=d6a6a0be4ee524f32b22941d6ca509bfFunctional classification and experimental dissection of long noncoding RNAsKopp, Florian; Mendell, Joshua T.Cell (Cambridge, MA, United States) (2018), 172 (3), 393-407CODEN: CELLB5; ISSN:0092-8674. (Cell Press)A review. Over the last decade, it has been increasingly demonstrated that the genomes of many species are pervasively transcribed, resulting in the prodn. of numerous long noncoding RNAs (lncRNAs). At the same time, it is now appreciated that many types of DNA regulatory elements, such as enhancers and promoters, regularly initiate bi-directional transcription. Thus, discerning functional noncoding transcripts from a vast transcriptome is a paramount priority, and challenge, for the lncRNA field. In this review, we aim to provide a conceptual and exptl. framework for classifying and elucidating lncRNA function. We categorize lncRNA loci into those that regulate gene expression in cis vs. those that perform functions in trans and propose an exptl. approach to dissect lncRNA activity based on these classifications. These strategies to further understand lncRNAs promise to reveal new and unanticipated biol. with great potential to advance our understanding of normal physiol. and disease.
- 43Freitas, A. A. Comprehensible classification models: a position paper. SIGKDD Explor. Newsl. 2014, 15 (1), 1– 10, DOI: 10.1145/2594473.2594475
- 44Tzelepis, K.; Koike-Yusa, H.; De Braekeleer, E.; Li, Y.; Metzakopian, E.; Dovey, O. M.; Mupo, A.; Grinkevich, V.; Li, M.; Mazan, M.; Gozdecka, M.; Ohnishi, S.; Cooper, J.; Patel, M.; McKerrell, T.; Chen, B.; Domingues, A. F.; Gallipoli, P.; Teichmann, S.; Ponstingl, H.; McDermott, U.; Saez-Rodriguez, J.; Huntly, B. J. P.; Iorio, F.; Pina, C.; Vassiliou, G. S.; Yusa, K. A CRISPR Dropout Screen Identifies Genetic Vulnerabilities and Therapeutic Targets in Acute Myeloid Leukemia. Cell Rep. 2016, 17 (4), 1193– 1205, DOI: 10.1016/j.celrep.2016.09.079[Crossref], [PubMed], [CAS], Google Scholar44https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC28XhslSntLjM&md5=8b891343b0fb43fd6cf39d8ed8ee29c4A CRISPR Dropout Screen Identifies Genetic Vulnerabilities and Therapeutic Targets in Acute Myeloid LeukemiaTzelepis, Konstantinos; Koike-Yusa, Hiroko; De Braekeleer, Etienne; Li, Yilong; Metzakopian, Emmanouil; Dovey, Oliver M.; Mupo, Annalisa; Grinkevich, Vera; Li, Meng; Mazan, Milena; Gozdecka, Malgorzata; Ohnishi, Shuhei; Cooper, Jonathan; Patel, Miten; McKerrell, Thomas; Chen, Bin; Domingues, Ana Filipa; Gallipoli, Paolo; Teichmann, Sarah; Ponstingl, Hannes; McDermott, Ultan; Saez-Rodriguez, Julio; Huntly, Brian J. P.; Iorio, Francesco; Pina, Cristina; Vassiliou, George S.; Yusa, KosukeCell Reports (2016), 17 (4), 1193-1205CODEN: CREED8; ISSN:2211-1247. (Cell Press)Acute myeloid leukemia (AML) is an aggressive cancer with a poor prognosis, for which mainstream treatments have not changed for decades. To identify addnl. therapeutic targets in AML, we optimize a genome-wide clustered regularly interspaced short palindromic repeats (CRISPR) screening platform and use it to identify genetic vulnerabilities in AML cells. We identify 492 AML-specific cell-essential genes, including several established therapeutic targets such as DOT1L, BCL2, and MEN1, and many other genes including clin. actionable candidates. We validate selected genes using genetic and pharmacol. inhibition, and chose KAT2A as a candidate for downstream study. KAT2A inhibition demonstrated anti-AML activity by inducing myeloid differentiation and apoptosis, and suppressed the growth of primary human AMLs of diverse genotypes while sparing normal hemopoietic stem-progenitor cells. Our results propose that KAT2A inhibition should be investigated as a therapeutic strategy in AML and provide a large no. of genetic vulnerabilities of this leukemia that can be pursued in downstream studies.
- 45Dobin, A.; Davis, C. A.; Schlesinger, F.; Drenkow, J.; Zaleski, C.; Jha, S.; Batut, P.; Chaisson, M.; Gingeras, T. R. STAR: ultrafast universal RNA-seq aligner. Bioinformatics 2013, 29 (1), 15– 21, DOI: 10.1093/bioinformatics/bts635[Crossref], [PubMed], [CAS], Google Scholar45https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC38XhvV2gsbnF&md5=9b8cfeabbb51258d6c450d4fe928052fSTAR: ultrafast universal RNA-seq alignerDobin, Alexander; Davis, Carrie A.; Schlesinger, Felix; Drenkow, Jorg; Zaleski, Chris; Jha, Sonali; Batut, Philippe; Chaisson, Mark; Gingeras, Thomas R.Bioinformatics (2013), 29 (1), 15-21CODEN: BOINFP; ISSN:1367-4803. (Oxford University Press)Motivation: Accurate alignment of high-throughput RNA-seq data is a challenging and yet unsolved problem because of the non-contiguous transcript structure, relatively short read lengths and constantly increasing throughput of the sequencing technologies. Currently available RNA-seq aligners suffer from high mapping error rates, low mapping speed, read length limitation and mapping biases. Results: To align our large (>80 billon reads) ENCODE Transcriptome RNA-seq dataset, we developed the Spliced Transcripts Alignment to a Ref. (STAR) software based on a previously undescribed RNA-seq alignment algorithm that uses sequential max. mappable seed search in uncompressed suffix arrays followed by seed clustering and stitching procedure. STAR outperforms other aligners by a factor of >50 in mapping speed, aligning to the human genome 550 million 2 × 76 bp paired-end reads per h on a modest 12-core server, while at the same time improving alignment sensitivity and precision. In addn. to unbiased de novo detection of canonical junctions, STAR can discover non-canonical splices and chimeric (fusion) transcripts, and is also capable of mapping full-length RNA sequences. Using Roche 454 sequencing of reverse transcription polymerase chain reaction amplicons, we exptl. validated 1960 novel intergenic splice junctions with an 80-90% success rate, corroborating the high precision of the STAR mapping strategy.
- 46Ramírez, F.; Ryan, D. P.; Grüning, B.; Bhardwaj, V.; Kilpert, F.; Richter, A. S.; Heyne, S.; Dündar, F.; Manke, T. deepTools2: a next generation web server for deep-sequencing data analysis. Nucleic Acids Res. 2016, 44 (W1), W160– W165, DOI: 10.1093/nar/gkw257[Crossref], [PubMed], [CAS], Google Scholar46https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2sXhtV2itrfI&md5=d4be278c28c75bdaea672a9420efef8fdeepTools2: a next generation web server for deep-sequencing data analysisRamirez, Fidel; Ryan, Devon P.; Gruening, Bjoern; Bhardwaj, Vivek; Kilpert, Fabian; Richter, Andreas S.; Heyne, Steffen; Duendar, Friederike; Manke, ThomasNucleic Acids Research (2016), 44 (W1), W160-W165CODEN: NARHAD; ISSN:0305-1048. (Oxford University Press)We present an update to our Galaxy-based web server for processing and visualizing deeply sequenced data. Its core tool set, deepTools, allows users to perform complete bioinformatic workflows ranging from quality controls and normalizations of aligned reads to integrative analyses, including clustering and visualization approaches. Since we first described our deepTools Galaxy server in 2014, we have implemented new solns. for many requests from the community and our users. Here, we introduce significant enhancements and new tools to further improve data visualization and interpretation. DeepTools continue to be open to all users and freely available as a web service. The new deepTools2 suite can be easily deployed within any Galaxy framework via the toolshed repository, and we also provide source code for command line usage under Linux and Mac OS X. A public and documented API for access to deepTools functionality is also available.
- 47Quinlan, A. R.; Hall, I. M. BEDTools: a flexible suite of utilities for comparing genomic features. Bioinformatics 2010, 26 (6), 841– 842, DOI: 10.1093/bioinformatics/btq033[Crossref], [PubMed], [CAS], Google Scholar47https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3cXivFGkurc%253D&md5=508a4f647b8c205fdac8358528f3e835BEDTools: a flexible suite of utilities for comparing genomic featuresQuinlan, Aaron R.; Hall, Ira M.Bioinformatics (2010), 26 (6), 841-842CODEN: BOINFP; ISSN:1367-4803. (Oxford University Press)Testing for correlations between different sets of genomic features is a fundamental task in genomics research. However, searching for overlaps between features with existing web-based methods is complicated by the massive datasets that are routinely produced with current sequencing technologies. Fast and flexible tools are therefore required to ask complex questions of these data in an efficient manner. This article introduces a new software suite for the comparison, manipulation and annotation of genomic features in Browser Extensible Data (BED) and General Feature Format (GFF) format. BEDTools also supports the comparison of sequence alignments in BAM format to both BED and GFF features. The tools are extremely efficient and allow the user to compare large datasets (e.g. next-generation sequencing data) with both public and custom genome annotation tracks. BEDTools can be combined with one another as well as with std. UNIX commands, thus facilitating routine genomics tasks as well as pipelines that can quickly answer intricate questions of large genomic datasets.
- 48Li, H.; Handsaker, B.; Wysoker, A.; Fennell, T.; Ruan, J.; Homer, N.; Marth, G.; Abecasis, G.; Durbin, R.; Genome Project Data Processing, S. The Sequence Alignment/Map format and SAMtools. Bioinformatics 2009, 25 (16), 2078– 2079, DOI: 10.1093/bioinformatics/btp352[Crossref], [PubMed], [CAS], Google Scholar48https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD1MXpslertr8%253D&md5=1ab7714968487a35cce7f81b751a0b1aThe Sequence Alignment/Map format and SAMtoolsLi, Heng; Handsaker, Bob; Wysoker, Alec; Fennell, Tim; Ruan, Jue; Homer, Nils; Marth, Gabor; Abecasis, Goncalo; Durbin, RichardBioinformatics (2009), 25 (16), 2078-2079CODEN: BOINFP; ISSN:1367-4803. (Oxford University Press)Summary: The Sequence Alignment/Map (SAM) format is a generic alignment format for storing read alignments against ref. sequences, supporting short and long reads (up to 128 Mbp) produced by different sequencing platforms. It is flexible in style, compact in size, efficient in random access and is the format in which alignments from the 1000 Genomes Project are released. SAMtools implements various utilities for post-processing alignments in the SAM format, such as indexing, variant caller and alignment viewer, and thus provides universal tools for processing read alignments. Availability: http://samtools.sourceforge.net Contact: [email protected]
- 49Zhang, Y.; Liu, T.; Meyer, C. A.; Eeckhoute, J.; Johnson, D. S.; Bernstein, B. E.; Nussbaum, C.; Myers, R. M.; Brown, M.; Li, W.; Liu, X. S. Model-based Analysis of ChIP-Seq (MACS). Genome Biol. 2008, 9 (9), R137, DOI: 10.1186/gb-2008-9-9-r137
- 50Machanick, P.; Bailey, T. L. MEME-ChIP: motif analysis of large DNA datasets. Bioinformatics 2011, 27 (12), 1696– 1697, DOI: 10.1093/bioinformatics/btr189[Crossref], [PubMed], [CAS], Google Scholar50https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3MXntFGkurw%253D&md5=8868fb42f9aca7fb2fc85c3aefdefaafMEME-ChIP: motif analysis of large DNA datasetsMachanick, Philip; Bailey, Timothy L.Bioinformatics (2011), 27 (12), 1696-1697CODEN: BOINFP; ISSN:1367-4803. (Oxford University Press)Motivation: Advances in high-throughput sequencing have resulted in rapid growth in large, high-quality datasets including those arising from transcription factor (TF) ChIP-seq expts. While there are many existing tools for discovering TF binding site motifs in such datasets, most web-based tools cannot directly process such large datasets. Results: The MEME-ChIP web service is designed to analyze ChIP-seq peak regions'-short genomic regions surrounding declared ChIP-seq peaks'. Given a set of genomic regions, it performs (i) ab initio motif discovery, (ii) motif enrichment anal., (iii) motif visualization, (iv) binding affinity anal. and (v) motif identification. It runs two complementary motif discovery algorithms on the input data-MEME and DREME-and uses the motifs they discover in subsequent visualization, binding affinity and identification steps. MEME-ChIP also performs motif enrichment anal. using the AME algorithm, which can detect very low levels of enrichment of binding sites for TFs with known DNA-binding motifs. Importantly, unlike with the MEME web service, there is no restriction on the size or no. of uploaded sequences, allowing very large ChIP-seq datasets to be analyzed. The analyses performed by MEME-ChIP provide the user with a varied view of the binding and regulatory activity of the ChIP-ed TF, as well as the possible involvement of other DNA-binding TFs.
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- Allen C. Zhu, Chuan He. Global Detection of RNA Methylation by Click Degradation. ACS Central Science 2020, 6 (12) , 2126-2129. https://doi.org/10.1021/acscentsci.0c01449
Abstract

Figure 1

Figure 1. meCLICK-Seq, a small molecule-based methylated RNA editing platform. (a) Proposed mechanism of action of meCLICK-Seq. (b) Conversion of PropSeMet into SeAdoYn and subsequent introduction of propargyl groups into RNA. (c) Functionalization of propargylated RNA with the click-degrader. (d) Proposed mechanism of the general base RNA degradation. (e) Copper-mediated RNA degradation.
Figure 2

Figure 2. Study of the chemical mechanism of click-degraders. (a) Time-dependent degradation of click-degrader 1 functionalized RNA 11-mer at 37 °C. n = 2. (b) Extent of RNA degradation after 14 h at 37 °C, pH 7.5, n = 2. (c) Extent of RNA degradation after 14 h at 37 °C, pH 3.0, n = 2. (d) Extent of RNA degradation in neutral and acidic conditions, n = 2. (e) Extent of RNA degradation after 14 h at 37 °C, pH 7.5, with PEG linkers of differing lengths. Cinitial corresponds to initial concentration; C corresponds to concentration at a specified time point. Click-degraders 1, 2, and 3 have linkers with 6, 4, and 2 PEG subunits, respectively, n = 2. Error bars represent SD.
Figure 3

Figure 3. meCLICK-Seq elucidates the relationship between m6A writers and methylation of mRNAs and lncRNAs. (a) meCLICK-Seq workflow. (b) Western blots demonstrate the extent of METTL3 and METTL16 depletion in conditional knock-down MOLM-13 cells treated with PropSeMet. Application of click-degrader does not significantly alter the levels of MTases. (c) Heat map showing decrease of methylated mRNA levels upon clicking and rescue of METTL3-dependent transcripts upon METTL3 depletion. (d) Overlap of m6A-containing mRNAs determined through m6A miCLIP and METTL3 mRNA substrates determined by meCLICK-Seq; significance indicated by Fisher’s exact test. (e) RT-qPCR-based meCLICK-Seq validation of a panel of genes, n = 3. (f) RT-qPCR-based meCLICK-Seq validation of a panel of genes in METTL3 depleted cells, n = 3. (g) Genome browser snapshot of NEAT1. Applying click machinery diminishes the WT but not METTL3 or METTL16 levels. p values determined with one-tailed t test. ns = not significant (p ≥ 0.05). Error bars represent SD.
Figure 4

Figure 4. meCLICK-Seq reveals widespread m6A mark in introns and intergenic regions. (a) Intronic peaks in the first intron of FLI1. (b) Intronic peaks in the first intron of CADM1 in three isogenic cell models. Intronic peaks are abolished specifically in METTL16-KD cells. (c) Overlap between METTL3- and METTL16-dependent intronic peaks. (d) Distribution of METTL3-dependent peaks in intronic and intergenic regions. (e) Distribution of METTL16-dependent peaks in intronic and intergenic regions. (f) RT-qPCR-based validation of a panel intronic peaks, n = 3. (g) Validation of dependence of intronic peaks on RNA methylases METTL3 and METTL16, n = 3. (h) Results of m6A-RIP in cells with methylated introns removed by dual gRNA system, n = 3. (i) Results of m6A-RIP in cells with depleted METTL3, n = 3. (j) Results of m6A-RIP in cells with depleted METTL16. RASA3 peak 2 is not affected by the knock-down illustrating that the observed effect is enzyme-specific, n = 3. ns = not significant (p ≥ 0.05). Error bars represent SD.
References
ARTICLE SECTIONSThis article references 50 other publications.
- 1Meyer, S.; Temme, C.; Wahle, E. Messenger RNA Turnover in Eukaryotes: Pathways and Enzymes. Crit. Rev. Biochem. Mol. Biol. 2004, 39 (4), 197– 216, DOI: 10.1080/10409230490513991[Crossref], [PubMed], [CAS], Google Scholar1https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD2cXovFGgsbY%253D&md5=7aa734bab93387c9f1519ae68c546e88Messenger RNA Turnover in Eukaryotes: Pathways and EnzymesMeyer, Sylke; Temme, Claudia; Wahle, ElmarCritical Reviews in Biochemistry and Molecular Biology (2004), 39 (4), 197-216CODEN: CRBBEJ; ISSN:1040-9238. (Taylor & Francis, Inc.)A review. The control of mRNA degrdn. is an important component of the regulation of gene expression since the steady-state concn. of mRNA is detd. both by the rates of synthesis and of decay. Two general pathways of mRNA decay have been described in eukaryotes. Both pathways share the exonucleolytic removal of the poly(A) tail (deadenylation) as the first step. In one pathway, deadenylation is followed by the hydrolysis of the cap and processive degrdn. of the mRNA body by a 5'exonuclease. In the second pathway, the mRNA body is degraded by a complex of 3'exonucleases before the remaining cap structure is hydrolyzed. This review discusses the proteins involved in the catalysis and control of both decay pathways.
- 2Shu, X.; Cao, J.; Cheng, M.; Xiang, S.; Gao, M.; Li, T.; Ying, X.; Wang, F.; Yue, Y.; Lu, Z.; Dai, Q.; Cui, X.; Ma, L.; Wang, Y.; He, C.; Feng, X.; Liu, J. A metabolic labeling method detects m6A transcriptome-wide at single base resolution. Nat. Chem. Biol. 2020, 16 (8), 887– 895, DOI: 10.1038/s41589-020-0526-9[Crossref], [PubMed], [CAS], Google Scholar2https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BB3cXotVCjur0%253D&md5=1793171884fef97b342913c2b6b847d3A metabolic labeling method detects m6A transcriptome-wide at single base resolutionShu, Xiao; Cao, Jie; Cheng, Mohan; Xiang, Siying; Gao, Minsong; Li, Ting; Ying, Xiner; Wang, Fengqin; Yue, Yanan; Lu, Zhike; Dai, Qing; Cui, Xiaolong; Ma, Lijia; Wang, Yizhen; He, Chuan; Feng, Xinhua; Liu, JianzhaoNature Chemical Biology (2020), 16 (8), 887-895CODEN: NCBABT; ISSN:1552-4450. (Nature Research)Transcriptome-wide mapping of N6-methyladenosine (m6A) at base resoln. remains an issue, impeding the authors' understanding of m6A roles at the nucleotide level. Here, the authors report a metabolic labeling method to detect mRNA m6A transcriptome-wide at base resoln., called 'm6A-label-seq'. Human and mouse cells could be fed with a methionine analog, Se-allyl-L-selenohomocysteine, which substitutes the Me group on the enzyme cofactor SAM with the allyl. Cellular RNAs could therefore be metabolically modified with N6-allyladenosine (a6A) at supposed m6A-generating adenosine sites. The authors pinpointed the mRNA a6A locations based on iodination-induced misincorporation at the opposite site in complementary DNA during reverse transcription. The authors identified a few thousand mRNA m6A sites in human HeLa, HEK293T and mouse H2.35 cells, carried out a parallel comparison of m6A-label-seq with available m6A sequencing methods, and validated selected sites by an orthogonal method. This method offers advantages in detecting clustered m6A sites and holds promise to locate nuclear nascent RNA m6A modifications.
- 3Shi, Y. Mechanistic insights into precursor messenger RNA splicing by the spliceosome. Nat. Rev. Mol. Cell Biol. 2017, 18 (11), 655– 670, DOI: 10.1038/nrm.2017.86[Crossref], [PubMed], [CAS], Google Scholar3https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2sXhsFKisb%252FE&md5=cbd7c32a25d27aa9e6958bab679e5869Mechanistic insights into precursor messenger RNA splicing by the spliceosomeShi, YigongNature Reviews Molecular Cell Biology (2017), 18 (11), 655-670CODEN: NRMCBP; ISSN:1471-0072. (Nature Research)A review. Precursor mRNA (pre-mRNA) splicing is an essential step in the flow of information from DNA to protein in all eukaryotes. Research over the past four decades has molecularly delineated the splicing pathway, including characterization of the detailed splicing reaction, definition of the spliceosome and identification of its components, and biochem. anal. of the various splicing complexes and their regulation. Structural information is central to mechanistic understanding of pre-mRNA splicing by the spliceosome. X-ray crystallog. of the spliceosomal components and subcomplexes is complemented by electron microscopy of the intact spliceosome. In this Review, I discuss recent at.-resoln. structures of the intact spliceosome at different stages of the splicing cycle. These structures have provided considerable mechanistic insight into pre-mRNA splicing and have corroborated and explained a large body of genetic and biochem. data. Together, the structural data have proved that the spliceosome is a protein-directed metalloribozyme.
- 4Chakrabarti, A.; Jha, B. K.; Silverman, R. H. New Insights into the Role of RNase L in Innate Immunity. J. Interferon Cytokine Res. 2011, 31 (1), 49– 57, DOI: 10.1089/jir.2010.0120[Crossref], [PubMed], [CAS], Google Scholar4https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3MXlt1Omuw%253D%253D&md5=fd42c2c66f4de908799e5b96d705ff1fNew Insights into the Role of RNase L in Innate ImmunityChakrabarti, Arindam; Jha, Babal Kant; Silverman, Robert H.Journal of Interferon & Cytokine Research (2011), 31 (1), 49-57CODEN: JICRFJ; ISSN:1079-9907. (Mary Ann Liebert, Inc.)A review. The interferon (IFN)-inducible 2'-5'-oligoadenylate synthetase (OAS)/RNase L pathway blocks infections by some types of viruses through cleavage of viral and cellular single-stranded RNA. Viruses induce type I IFNs that initiate signaling to the OAS genes. OAS proteins are pathogen recognition receptors for the viral pathogen-assocd. mol. pattern, double-stranded RNA. Double-stranded RNA activates OAS to produce px5'A(2'p5'A)n; x = 1-3; n > 2 (2-5A) from ATP. Upon binding 2-5A, RNase L is converted from an inactive monomer to a potently active dimeric endoribonuclease for single-stranded RNA. RNase L contains, from N- to C-terminus, a series of 9 ankyrin repeats, a linker, several protein kinase-like motifs, and a RNase domain homologous to Ire1 (involved in the unfolded protein response). In the past few years, it has become increasingly apparent that RNase L and OAS contribute to innate immunity in many ways. For example, small RNA cleavage products produced by RNase L during viral infections can signal to the retinoic acid-inducible-I like receptors to amplify and perpetuate signaling to the IFN-β gene. In addn., RNase L is now implicated in protecting the central nervous system against viral-induced demyelination. A role in tumor suppression was inferred by mapping of the RNase L gene to the hereditary prostate cancer 1 (HPC1) gene, which in turn led to discovery of the xenotropic murine leukemia-related virus. A broader role in innate immunity is suggested by involvement of RNase L in cytokine induction and endosomal pathways that suppress bacterial infections. These newly described findings about RNase L could eventually provide the basis for developing broad-spectrum antimicrobial drugs.
- 5Deng, Y.; Wang, C. C.; Choy, K. W.; Du, Q.; Chen, J.; Wang, Q.; Li, L.; Chung, T. K. H.; Tang, T. Therapeutic potentials of gene silencing by RNA interference: Principles, challenges, and new strategies. Gene 2014, 538 (2), 217– 227, DOI: 10.1016/j.gene.2013.12.019[Crossref], [PubMed], [CAS], Google Scholar5https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2cXhs1Clt7w%253D&md5=cafe0ad284fd463c6cd9c3b5757de4f1Therapeutic potentials of gene silencing by RNA interference: Principles, challenges, and new strategiesDeng, Yan; Wang, Chi Chiu; Choy, Kwong Wai; Du, Quan; Chen, Jiao; Wang, Qin; Li, Lu; Chung, Tony Kwok Hung; Tang, TaoGene (2014), 538 (2), 217-227CODEN: GENED6; ISSN:0378-1119. (Elsevier B.V.)A review. During recent decades there have been remarkable advances in biol., in which one of the most important discoveries is RNA interference (RNAi). RNAi is a specific post-transcriptional regulatory pathway that can result in silencing gene functions. Efforts have been done to translate this new discovery into clin. applications for disease treatment. However, tech. difficulties restrict the development of RNAi, including stability, off-target effects, immunostimulation and delivery problems. Researchers have attempted to surmount these barriers and improve the bioavailability and safety of RNAi-based therapeutics by optimizing the chem. and structure of these mols. This paper aimed to describe the principles of RNA interference, review the therapeutic potential in various diseases and discuss the new strategies for in vivo delivery of RNAi to overcome the challenges.
- 6Cox, D. B. T.; Gootenberg, J. S.; Abudayyeh, O. O.; Franklin, B.; Kellner, M. J.; Joung, J.; Zhang, F. RNA editing with CRISPR-Cas13. Science 2017, 358 (6366), 1019, DOI: 10.1126/science.aaq0180[Crossref], [PubMed], [CAS], Google Scholar6https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2sXhvFahsb3J&md5=21ed8ebbd2cc334be0911129196e6b6eRNA editing with CRISPR-Cas13Cox, David B. T.; Gootenberg, Jonathan S.; Abudayyeh, Omar O.; Franklin, Brian; Kellner, Max J.; Joung, Julia; Zhang, FengScience (Washington, DC, United States) (2017), 358 (6366), 1019-1027CODEN: SCIEAS; ISSN:0036-8075. (American Association for the Advancement of Science)Nucleic acid editing holds promise for treating genetic disease, particularly at the RNA level, where disease-relevant sequences can be rescued to yield functional protein products. Type VI CRISPR-Cas systems contain the programmable single-effector RNA-guided RNase Cas13. We profiled type VI systems in order to engineer a Cas13 ortholog capable of robust knockdown and demonstrated RNA editing by using catalytically inactive Cas13 (dCas13) to direct adenosine-to-inosine deaminase activity by ADAR2 (adenosine deaminase acting on RNA type 2) to transcripts in mammalian cells. This system, referred to as RNA editing for programmable A to I replacement (REPAIR), which has no strict sequence constraints, can be used to edit full-length transcripts contg. pathogenic mutations. We further engineered this system to create a high-specificity variant and minimized the system to facilitate viral delivery. REPAIR presents a promising RNA-editing platform with broad applicability for research, therapeutics, and biotechnol.
- 7Costales, M. G.; Matsumoto, Y.; Velagapudi, S. P.; Disney, M. D. Small Molecule Targeted Recruitment of a Nuclease to RNA. J. Am. Chem. Soc. 2018, 140 (22), 6741– 6744, DOI: 10.1021/jacs.8b01233[ACS Full Text
], [CAS], Google Scholar7https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1cXpvFKktbs%253D&md5=7d4ccaad0cba3da84f924f244b8bcdbfSmall Molecule Targeted Recruitment of a Nuclease to RNACostales, Matthew G.; Matsumoto, Yasumasa; Velagapudi, Sai Pradeep; Disney, Matthew D.Journal of the American Chemical Society (2018), 140 (22), 6741-6744CODEN: JACSAT; ISSN:0002-7863. (American Chemical Society)The choreog. between RNA synthesis and degrdn. is a key determinant in biol. Engineered systems such as CRISPR have been developed to rid a cell of RNAs. Here, we show that a small mol. can recruit a nuclease to a specific transcript, triggering its destruction. A small mol. that selectively binds the oncogenic microRNA(miR)-96 hairpin precursor was appended with a short 2'-5' poly(A) oligonucleotide. The conjugate locally activated endogenous, latent RNase (RNase L), which selectively cleaved the miR-96 precursor in cancer cells in a catalytic fashion. Silencing miR-96 de-repressed pro-apoptotic FOXO1 transcription factor, triggering apoptosis in breast cancer, but not healthy breast, cells. These results demonstrate that small mols. can be programmed to selectively cleave RNA and has broad implications. - 8Li, Y.; Disney, M. D. Precise Small Molecule Degradation of a Noncoding RNA Identifies Cellular Binding Sites and Modulates an Oncogenic Phenotype. ACS Chem. Biol. 2018, 13 (11), 3065– 3071, DOI: 10.1021/acschembio.8b00827[ACS Full Text
], [CAS], Google Scholar8https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1cXitVamtbbP&md5=1d67850e24a1ed7eda6dbf2f26ea2a68Precise Small Molecule Degradation of a Noncoding RNA Identifies Cellular Binding Sites and Modulates an Oncogenic PhenotypeLi, Yue; Disney, Matthew D.ACS Chemical Biology (2018), 13 (11), 3065-3071CODEN: ACBCCT; ISSN:1554-8929. (American Chemical Society)Herein, we describe the precise cellular destruction of an oncogenic noncoding RNA with a small mol.-bleomycin A5 conjugate, affording reversal of phenotype and a facile method to map the cellular binding sites of a small mol. In particular, bleomycin A5 was coupled to a small mol. that selectively binds the microRNA-96 hairpin precursor (pri-miR-96). By coupling of bleomycin A5's free amine to the RNA binder, its affinity for binding to pri-miR-96 is >100-fold stronger than to DNA and the compd. selectively cleaves pri-miR-96 in triple neg. breast cancer (TNBC) cells. Indeed, selective cleavage of pri-miR-96 enhanced expression of FOXO1 protein, a pro-apoptotic transcription factor that miR-96 silences, and triggered apoptosis in TNBC cells. No effects were obsd. in healthy breast epithelial cells. Thus, conjugation to bleomycin A5's free amine may provide programmable control over its cellular targets. Few approaches are available to define the binding sites of small mols. within cellular RNAs. Our targeted cleavage approach provides such an approach that is straightforward to implement. That is, we detd. exptl. the site cleaved within pri-miR-96 in vitro and in cells; these studies revealed that the site of cleavage is the precise site for which the small mol. cleaver was designed and in agreement with modeling. These studies demonstrate the potential of sequence-based design to provide bioactive compds. that precisely recognize and cleave RNA in cells. - 9Tomkuviene, M.; Clouet-d’Orval, B.; Cerniauskas, I.; Weinhold, E.; Klimasauskas, S. Programmable sequence-specific click-labeling of RNA using archaeal box C/D RNP methyltransferases. Nucleic Acids Res. 2012, 40 (14), 6765– 6773, DOI: 10.1093/nar/gks381[Crossref], [PubMed], [CAS], Google Scholar9https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC38XhtF2rsLrE&md5=4e81250f3e4678cd15e0f0a98ddbf019Programmable sequence-specific click-labeling of RNA using archaeal box C/D RNP methyltransferasesTomkuviene, Migle; Clouet-d'Orval, Beatrice; Cerniauskas, Ignas; Weinhold, Elmar; Klimasauskas, SauliusNucleic Acids Research (2012), 40 (14), 6765-6773CODEN: NARHAD; ISSN:0305-1048. (Oxford University Press)Biophys. and mechanistic investigation of RNA function requires site-specific incorporation of spectroscopic and chem. probes, which is difficult to achieve using current technologies. We have in vitro reconstituted a functional box C/D small ribonucleoprotein RNA 2'-O-methyltransferase (C/D RNP) from the thermophilic archaeon Pyrococcus abyssi and demonstrated its ability to transfer a prop-2-ynyl group from a synthetic cofactor analog to a series of preselected target sites in model tRNA and pre-mRNA mols. Target selection of the RNP was programmed by changing a dodecanucleotide guide sequence in a 64-nt C/D guide RNA leading to efficient derivatization of three out of four new targets in each RNA substrate. We also show that the transferred terminal alkyne can be further appended with a fluorophore using a bioorthogonal azide-alkyne 1,3-cycloaddn. (click) reaction. The described approach for the first time permits synthetically tunable sequence-specific labeling of RNA with single-nucleotide precision.
- 10Meyer, K. D.; Saletore, Y.; Zumbo, P.; Elemento, O.; Mason, C. E.; Jaffrey, S. R. Comprehensive analysis of mRNA methylation reveals enrichment in 3′ UTRs and near stop codons. Cell 2012, 149 (7), 1635– 1646, DOI: 10.1016/j.cell.2012.05.003[Crossref], [PubMed], [CAS], Google Scholar10https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC38Xntlyrs7s%253D&md5=e0547faf06ce7cc5279c34d9ebb6f808Comprehensive analysis of mRNA methylation reveals enrichment in 3' UTRs and near stop codonsMeyer, Kate D.; Saletore, Yogesh; Zumbo, Paul; Elemento, Olivier; Mason, Christopher E.; Jaffrey, Samie R.Cell (Cambridge, MA, United States) (2012), 149 (7), 1635-1646CODEN: CELLB5; ISSN:0092-8674. (Cell Press)Methylation of the N6 position of adenosine (m6A) is a posttranscriptional modification of RNA with poorly understood prevalence and physiol. relevance. The recent discovery that FTO, an obesity risk gene, encodes an m6A demethylase implicates m6A as an important regulator of physiol. processes. Here, we present a method for transcriptome-wide m6A localization, which combines m6A-specific methylated RNA immunopptn. with next-generation sequencing (MeRIP-Seq). We use this method to identify mRNAs of 7676 mammalian genes that contain m6A, indicating that m6A is a common base modification of mRNA. The m6A modification exhibits tissue-specific regulation and is markedly increased throughout brain development. We find that m6A sites are enriched near stop codons and in 3' UTRs, and we uncover an assocn. between m6A residues and microRNA-binding sites within 3' UTRs. These findings provide a resource for identifying transcripts that are substrates for adenosine methylation and reveal insights into the epigenetic regulation of the mammalian transcriptome.
- 11Dominissini, D.; Moshitch-Moshkovitz, S.; Schwartz, S.; Salmon-Divon, M.; Ungar, L.; Osenberg, S.; Cesarkas, K.; Jacob-Hirsch, J.; Amariglio, N.; Kupiec, M.; Sorek, R.; Rechavi, G. Topology of the human and mouse m6A RNA methylomes revealed by m6A-seq. Nature 2012, 485 (7397), 201– 206, DOI: 10.1038/nature11112[Crossref], [PubMed], [CAS], Google Scholar11https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC38XmvVequ7g%253D&md5=e392a6533a536e9c142488a6ca3f678dTopology of the human and mouse m6A RNA methylomes revealed by m6A-seqDominissini, Dan; Moshitch-Moshkovitz, Sharon; Schwartz, Schraga; Salmon-Divon, Mali; Ungar, Lior; Osenberg, Sivan; Cesarkas, Karen; Jacob-Hirsch, Jasmine; Amariglio, Ninette; Kupiec, Martin; Sorek, Rotem; Rechavi, GideonNature (London, United Kingdom) (2012), 485 (7397), 201-206CODEN: NATUAS; ISSN:0028-0836. (Nature Publishing Group)An extensive repertoire of modifications is known to underlie the versatile coding, structural and catalytic functions of RNA, but it remains largely uncharted territory. Although biochem. studies indicate that N6-methyladenosine (m6A) is the most prevalent internal modification in mRNA, an in-depth study of its distribution and functions has been impeded by a lack of robust anal. methods. Here, we present the human and mouse m6A modification landscape in a transcriptome-wide manner, using a novel approach, m6A-seq, based on antibody-mediated capture and massively parallel sequencing. We identify over 12,000 m6A sites characterized by a typical consensus in the transcripts of more than 7,000 human genes. Sites preferentially appear in two distinct landmarks-around stop codons and within long internal exons-and are highly conserved between human and mouse. Although most sites are well preserved across normal and cancerous tissues and in response to various stimuli, a subset of stimulus-dependent, dynamically modulated sites is identified. Silencing the m6A methyltransferase significantly affects gene expression and alternative splicing patterns, resulting in modulation of the p53 (also known as TP53) signalling pathway and apoptosis. Our findings therefore suggest that RNA decoration by m6A has a fundamental role in regulation of gene expression.
- 12Linder, B.; Grozhik, A. V.; Olarerin-George, A. O.; Meydan, C.; Mason, C. E.; Jaffrey, S. R. Single-nucleotide-resolution mapping of m6A and m6Am throughout the transcriptome. Nat. Methods 2015, 12 (8), 767– 772, DOI: 10.1038/nmeth.3453[Crossref], [PubMed], [CAS], Google Scholar12https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2MXhtFWqur%252FE&md5=9d4f101a6ed91bb0ee5fa37be8530b51Single-nucleotide-resolution mapping of m6A and m6Am throughout the transcriptomeLinder, Bastian; Grozhik, Anya V.; Olarerin-George, Anthony O.; Meydan, Cem; Mason, Christopher E.; Jaffrey, Samie R.Nature Methods (2015), 12 (8), 767-772CODEN: NMAEA3; ISSN:1548-7091. (Nature Publishing Group)N6-methyladenosine (m6A) is the most abundant modified base in eukaryotic mRNA and has been linked to diverse effects on mRNA fate. Current mapping approaches localize m6A residues to transcript regions 100-200 nt long but cannot identify precise m6A positions on a transcriptome-wide level. Here we developed m6A individual-nucleotide-resoln. crosslinking and immunopptn. (miCLIP) and used it to demonstrate that antibodies to m6A can induce specific mutational signatures at m6A residues after UV light-induced antibody-RNA crosslinking and reverse transcription. We found that these antibodies similarly induced mutational signatures at N6,2'-O-dimethyladenosine (m6Am), a modification found at the first nucleotide of certain mRNAs. Using these signatures, we mapped m6A and m6Am at single-nucleotide resoln. in human and mouse mRNA and identified small nucleolar RNAs (snoRNAs) as a new class of m6A-contg. non-coding RNAs (ncRNAs).
- 13Zhang, Z.; Chen, L.-Q.; Zhao, Y.-L.; Yang, C.-G.; Roundtree, I. A.; Zhang, Z.; Ren, J.; Xie, W.; He, C.; Luo, G.-Z. Single-base mapping of m6A by an antibody-independent method. Sci. Adv. 2019, 5 (7), eaax0250, DOI: 10.1126/sciadv.aax0250
- 14Meyer, K. D. DART-seq: an antibody-free method for global m6A detection. Nat. Methods 2019, 16 (12), 1275– 1280, DOI: 10.1038/s41592-019-0570-0[Crossref], [PubMed], [CAS], Google Scholar14https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1MXhvVarsb3I&md5=2578ff8833ee276fc2bb75929fa9fcb3DART-seq: an antibody-free method for global m6A detectionMeyer, Kate D.Nature Methods (2019), 16 (12), 1275-1280CODEN: NMAEA3; ISSN:1548-7091. (Nature Research)N6-methyladenosine (m6A) is a widespread RNA modification that influences nearly every aspect of the mRNA lifecycle. Our understanding of m6A has been facilitated by the development of global m6A mapping methods, which use antibodies to immunoppt. methylated RNA. However, these methods have several limitations, including high input RNA requirements and cross-reactivity to other RNA modifications. Here, we present DART-seq (deamination adjacent to RNA modification targets), an antibody-free method for detecting m6A sites. In DART-seq, the cytidine deaminase APOBEC1 is fused to the m6A-binding YTH domain. APOBEC1-YTH expression in cells induces C-to-U deamination at sites adjacent to m6A residues, which are detected using std. RNA-seq. DART-seq identifies thousands of m6A sites in cells from as little as 10 ng of total RNA and can detect m6A accumulation in cells over time. Addnl., we use long-read DART-seq to gain insights into m6A distribution along the length of individual transcripts.
- 15Wang, Y.; Xiao, Y.; Dong, S.; Yu, Q.; Jia, G. Antibody-free enzyme-assisted chemical approach for detection of N6-methyladenosine. Nat. Chem. Biol. 2020, 16 (8), 896– 903, DOI: 10.1038/s41589-020-0525-x[Crossref], [PubMed], [CAS], Google Scholar15https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BB3cXotVCjur8%253D&md5=9d542adbb5a0272f274f6f6c5af60208Antibody-free enzyme-assisted chemical approach for detection of N6-methyladenosineWang, Ye; Xiao, Yu; Dong, Shunqing; Yu, Qiong; Jia, GuifangNature Chemical Biology (2020), 16 (8), 896-903CODEN: NCBABT; ISSN:1552-4450. (Nature Research)The inert chem. property of RNA modification N6-methyladenosine (m6A) makes it very challenging to detect. Most m6A sequencing methods rely on m6A-antibody immunopptn. and cannot distinguish m6A and N6,2'-O-dimethyladenosine modification at the cap +1 position (cap m6Am). Although the two antibody-free methods (m6A-REF-seq/MAZTER-seq and DART-seq) have been developed recently, they are dependent on m6A sequence or cellular transfection. Here, the authors present an antibody-free, FTO-assisted chem. labeling method termed m6A-SEAL for specific m6A detection. The authors applied m6A-SEAL to profile m6A landscapes in humans and plants, which displayed the known m6A distribution features in transcriptome. By doing a comparison with all available m6A sequencing methods and specific m6A sites validation by SELECT, m6A-SEAL has good sensitivity, specificity and reliability for transcriptome-wide detection of m6A. Given its tagging ability and FTO's oxidn. property, m6A-SEAL enables many applications such as enrichment, imaging and sequencing to drive future functional studies of m6A and other modifications.
- 16Hartstock, K.; Nilges, B. S.; Ovcharenko, A.; Cornelissen, N. V.; Püllen, N.; Lawrence-Dörner, A.-M.; Leidel, S. A.; Rentmeister, A. Enzymatic or In Vivo Installation of Propargyl Groups in Combination with Click Chemistry for the Enrichment and Detection of Methyltransferase Target Sites in RNA. Angew. Chem., Int. Ed. 2018, 57 (21), 6342– 6346, DOI: 10.1002/anie.201800188[Crossref], [CAS], Google Scholar16https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1cXlt1Ons7c%253D&md5=0c9d3948a841e3dfbda54d58120a80eeEnzymatic or In Vivo Installation of Propargyl Groups in Combination with Click Chemistry for the Enrichment and Detection of Methyltransferase Target Sites in RNAHartstock, Katja; Nilges, Benedikt S.; Ovcharenko, Anna; Cornelissen, Nicolas V.; Puellen, Nikolai; Lawrence-Doerner, Ann-Marie; Leidel, Sebastian A.; Rentmeister, AndreaAngewandte Chemie, International Edition (2018), 57 (21), 6342-6346CODEN: ACIEF5; ISSN:1433-7851. (Wiley-VCH Verlag GmbH & Co. KGaA)N6-methyladenosine (m6A) is the most abundant internal modification in eukaryotic mRNA. It is introduced by METTL3-METTL14 and tunes mRNA metab., impacting cell differentiation and development. Precise transcriptome-wide assignment of m6A sites is of utmost importance. However, m6A does not interfere with Watson-Crick base pairing, making polymerase-based detection challenging. We developed a chem. biol. approach for the precise mapping of methyltransferase (MTase) target sites based on the introduction of a bioorthogonal propargyl group in vitro and in cells. We show that propargyl groups can be introduced enzymically by wild-type METTL3-METTL14. Reverse transcription terminated up to 65 % at m6A sites after bioconjugation and purifn., hence enabling detection of METTL3-METTL14 target sites by next generation sequencing. Importantly, we implemented metabolic propargyl labeling of RNA MTase target sites in vivo based on propargyl-L-selenohomocysteine and validated different types of known rRNA methylation sites.
- 17Raines, R. T. Ribonuclease A. Chem. Rev. 1998, 98 (3), 1045– 1066, DOI: 10.1021/cr960427h[ACS Full Text
], [CAS], Google Scholar17https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaK1cXis12it7g%253D&md5=1e71aeda7dc7d4b6ac23f8c8ce8c2febRibonuclease ARaines, Ronald T.Chemical Reviews (Washington, D. C.) (1998), 98 (3), 1045-1065CODEN: CHREAY; ISSN:0009-2665. (American Chemical Society)A review with 420 refs., of the structure and function of RNase A, with emphasis on applications of recombinant DNA technol. and nucleic acid chem. - 18Cheng, L.; Abhilash, K. G.; Breslow, R. Binding and biomimetic cleavage of the RNA poly(U) by synthetic polyimidazoles. Proc. Natl. Acad. Sci. U. S. A. 2012, 109 (32), 12884, DOI: 10.1073/pnas.1210846109[Crossref], [PubMed], [CAS], Google Scholar18https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC38XhsVWmsrvL&md5=be5ae7559f5f5f9d0287738d97d985a5Binding and biomimetic cleavage of the RNA poly(U) by synthetic polyimidazolesCheng, Liang; Abhilash, K. G.; Breslow, RonaldProceedings of the National Academy of Sciences of the United States of America (2012), 109 (32), 12884-12887, S12884/1-S12884/5CODEN: PNASA6; ISSN:0027-8424. (National Academy of Sciences)Four polyimidazoles were used in the binding and cleavage studies with poly(U). The two polydisperse polyvinylimidazoles were previously described by others, while the other two new polymers of polyethyleneimines were prepd. by cationic polymn. of oxazolines. The latter had imidazole units attached to each nitrogen of the polymers. They were characterized by gel permeation chromatog. and had very low polydispersities. When they were partially protonated they bound to the poly(U) and catalyzed its cleavage by a process analogous to that used by the enzyme RNase A. The kinetics of the cleavage were followed by an assay we had previously described using phosphodiesterase I from Crotalus venom after the cleavage processes. Cleavage of poly(U) with Zn2+ was also examd., with and without the polymers. A scheme is described in which these cleavages could be made sequence selective with various RNAs, particularly with important targets, such as viral RNAs.
- 19Beloglazova, N. G.; Fabani, M. M.; Zenkova, M. A.; Bichenkova, E. V.; Polushin, N. N.; Sil’nikov, V. V.; Douglas, K. T.; Vlassov, V. V. Sequence-specific artificial ribonucleases. I. Bis -imidazole-containing oligonucleotide conjugates prepared using precursor-based strategy. Nucleic Acids Res. 2004, 32 (13), 3887– 3897, DOI: 10.1093/nar/gkh702[Crossref], [PubMed], [CAS], Google Scholar19https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD2cXmvFCjsLc%253D&md5=c81ecdfcbb5bdd2723a909e8aaaa3f36Sequence-specific artificial ribonucleases. I. Bis-imidazole-containing oligonucleotide conjugates prepared using precursor-based strategyBeloglazova, Natalia G.; Fabani, Martin M.; Zenkova, Marina A.; Bichenkova, Elena V.; Polushin, Nikolai N.; Sil'nikov, Vladimir V.; Douglas, Kenneth T.; Vlassov, Valentin V.Nucleic Acids Research (2004), 32 (13), 3887-3897CODEN: NARHAD; ISSN:0305-1048. (Oxford University Press)Antisense oligonucleotide conjugates, bearing constructs with two imidazole residues, were synthesized using a precursor-based technique employing post-synthetic histamine functionalization of oligonucleotides bearing methoxyoxalamido precursors at the 5'-termini. The conjugates were assessed in terms of their cleavage activities using both biochem. assays and conformational anal. by mol. modeling. The oligonucleotide part of the conjugates was complementary to the T-arm of yeast tRNAPhe (44-60 nt) and was expected to deliver imidazole groups near the fragile sequence C61-ACA-G65 of the tRNA. The conjugates showed RNase activity at neutral pH and physiol. temp. resulting in complete cleavage of the target RNA, mainly at the C63-A64 phosphodiester bond. For some constructs, cleavage was completed within 1-2 h under optimal conditions. Mol. modeling was used to det. the preferred orientation(s) of the cleaving group(s) in the complexes of the conjugates with RNA target. Cleaving constructs bearing two imidazole residues were found to be conformationally highly flexible, adopting no preferred specific conformation. No interactions other than complementary base pairing between the conjugates and the target were found to be the factors stabilizing the active cleaving conformation(s).
- 20Li, Z.-R.; Li, J.; Cai, W.; Lai, J. Y. H.; McKinnie, S. M. K.; Zhang, W.-P.; Moore, B. S.; Zhang, W.; Qian, P.-Y. Macrocyclic colibactin induces DNA double-strand breaks via copper-mediated oxidative cleavage. Nat. Chem. 2019, 11 (10), 880– 889, DOI: 10.1038/s41557-019-0317-7[Crossref], [PubMed], [CAS], Google Scholar20https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1MXhvVSkurvJ&md5=6c3a9fbfc5555f4a3387b39d3cdb2383Macrocyclic colibactin induces DNA double-strand breaks via copper-mediated oxidative cleavageLi, Zhong-Rui; Li, Jie; Cai, Wenlong; Lai, Jennifer Y. H.; McKinnie, Shaun M. K.; Zhang, Wei-Peng; Moore, Bradley S.; Zhang, Wenjun; Qian, Pei-YuanNature Chemistry (2019), 11 (10), 880-889CODEN: NCAHBB; ISSN:1755-4330. (Nature Research)Colibactin is an assumed human gut bacterial genotoxin, whose biosynthesis is linked to the clb genomic island that has a widespread distribution in pathogenic and commensal human enterobacteria. Colibactin-producing gut microbes promote colon tumor formation and enhance the progression of colorectal cancer via cellular senescence and death induced by DNA double-strand breaks (DSBs); however, the chem. basis that contributes to the pathogenesis at the mol. level has not been fully characterized. Here, the authors report the discovery of colibactin-645, a macrocyclic colibactin metabolite that recapitulates the previously assumed genotoxicity and cytotoxicity. Colibactin-645 shows strong DNA DSB activity in vitro and in human cell cultures via a unique copper-mediated oxidative mechanism. The authors also delineate a complete biosynthetic model for colibactin-645, which highlights a unique fate of the aminomalonate-building monomer in forming the C-terminal 5-hydroxy-4-oxazolecarboxylic acid moiety through the activities of both the polyketide synthase ClbO and the amidase ClbL. This work thus provides a mol. basis for colibactin's DNA DSB activity and facilitates further mechanistic study of colibactin-related colorectal cancer incidence and prevention.
- 21Peterson, J. R.; Thor, S.; Kohler, L.; Kohler, P. R. A.; Metcalf, W. W.; Luthey-Schulten, Z. Genome-wide gene expression and RNA half-life measurements allow predictions of regulation and metabolic behavior in Methanosarcina acetivorans. BMC Genomics 2016, 17, 924, DOI: 10.1186/s12864-016-3219-8[Crossref], [PubMed], [CAS], Google Scholar21https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1cXhtlWkur0%253D&md5=87bcf9df8a1aebb3c6b02978e0989738Genome-wide gene expression and RNA half-life measurements allow predictions of regulation and metabolic behavior in Methanosarcina acetivoransPeterson, Joseph R.; Thor, Sheng Shee; Kohler, Lars; Kohler, Petra R. A.; Metcalf, William W.; Luthey-Schulten, ZaidaBMC Genomics (2016), 17 (), 924/1-924/23CODEN: BGMEET; ISSN:1471-2164. (BioMed Central Ltd.)While a few studies on the variations in mRNA expression and half-lives measured under different growth conditions have been used to predict patterns of regulation in bacterial organisms, the extent to which this information can also play a role in defining metabolic phenotypes has yet to be examd. systematically. Here we present the first comprehensive study for a model methanogen. We use expression and half-life data for the methanogen Methanosarcina acetivorans growing on fast- and slow-growth substrates to examine the regulation of its genes. Unlike Escherichia coli where only small shifts in half-lives were obsd., we found that most mRNA have significantly longer half-lives for slow growth on acetate compared to fast growth on methanol or trimethylamine. Interestingly, half-life shifts are not uniform across functional classes of enzymes, suggesting the existence of a selective stabilization mechanism for mRNAs. Using the transcriptomics data we detd. whether transcription or degrdn. rate controls the change in transcript abundance. Degrdn. was found to control abundance for about half of the metabolic genes underscoring its role in regulating metab. Genes involved in half of the metabolic reactions were found to be differentially expressed among the substrates suggesting the existence of drastically different metabolic phenotypes that extend beyond just the methanogenesis pathways. By integrating expression data with an updated metabolic model of the organism (iST807) significant differences in pathway flux and prodn. of metabolites were predicted for the three growth substrates. This study provides the first global picture of differential expression and half-lives for a class II methanogen, as well as provides the first evidence in a single organism that drastic genome-wide shifts in RNA half-lives can be modulated by growth substrate. We detd. which genes in each metabolic pathway control the flux and classified them as regulated by transcription (e.g. transcription factor) or degrdn. (e.g. post-transcriptional modification). We found that more than half of genes in metab. were controlled by degrdn. Our results suggest that M. acetivorans employs extensive post-transcriptional regulation to optimize key metabolic steps, and more generally that degrdn. could play a much greater role in optimizing an organism's metab. than previously thought.
- 22Oivanen, M.; Kuusela, S.; Lönnberg, H. Kinetics and Mechanisms for the Cleavage and Isomerization of the Phosphodiester Bonds of RNA by Brønsted Acids and Bases. Chem. Rev. 1998, 98 (3), 961– 990, DOI: 10.1021/cr960425x[ACS Full Text
], [CAS], Google Scholar22https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaK1cXis1yqu7s%253D&md5=890374fb922f9ad0d2d871d264b63c9cKinetics and Mechanisms for the Cleavage and Isomerization of the Phosphodiester Bonds of RNA by Bronsted Acids and BasesOivanen, Mikko; Kuusela, Satu; Loennberg, HarriChemical Reviews (Washington, D. C.) (1998), 98 (3), 961-990CODEN: CHREAY; ISSN:0009-2665. (American Chemical Society)A review with 240 refs. on acid/base catalyzed cleavage and isomerization of the 3',5'-phosphodiester bonds of DNA. - 23Barbieri, I.; Tzelepis, K.; Pandolfini, L.; Shi, J.; Millán-Zambrano, G.; Robson, S. C.; Aspris, D.; Migliori, V.; Bannister, A. J.; Han, N.; De Braekeleer, E.; Ponstingl, H.; Hendrick, A.; Vakoc, C. R.; Vassiliou, G. S.; Kouzarides, T. Promoter-bound METTL3 maintains myeloid leukaemia by m6A-dependent translation control. Nature 2017, 552 (7683), 126– 131, DOI: 10.1038/nature24678[Crossref], [PubMed], [CAS], Google Scholar23https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2sXhvVynsb7N&md5=47c1daa65a18c808a4b0f6f31774fb45Promoter-bound METTL3 maintains myeloid leukaemia by m6A-dependent translation controlBarbieri, Isaia; Tzelepis, Konstantinos; Pandolfini, Luca; Shi, Junwei; Millan-Zambrano, Gonzalo; Robson, Samuel C.; Aspris, Demetrios; Migliori, Valentina; Bannister, Andrew J.; Han, Namshik; De Braekeleer, Etienne; Ponstingl, Hannes; Hendrick, Alan; Vakoc, Christopher R.; Vassiliou, George S.; Kouzarides, TonyNature (London, United Kingdom) (2017), 552 (7683), 126-131CODEN: NATUAS; ISSN:0028-0836. (Nature Research)N6-methyladenosine (m6A) is an abundant internal RNA modification in both coding and non-coding RNAs that is catalyzed by the METTL3-METTL14 methyltransferase complex. However, the specific role of these enzymes in cancer is still largely unknown. Here we define a pathway that is specific for METTL3 and is implicated in the maintenance of a leukemic state. We identify METTL3 as an essential gene for growth of acute myeloid leukemia cells in two distinct genetic screens. Downregulation of METTL3 results in cell cycle arrest, differentiation of leukemic cells and failure to establish leukemia in immunodeficient mice. We show that METTL3, independently of METTL14, assocs. with chromatin and localizes to the transcriptional start sites of active genes. The vast majority of these genes have the CAATT-box binding protein CEBPZ present at the transcriptional start site, and this is required for recruitment of METTL3 to chromatin. Promoter-bound METTL3 induces m6A modification within the coding region of the assocd. mRNA transcript, and enhances its translation by relieving ribosome stalling. We show that genes regulated by METTL3 in this way are necessary for acute myeloid leukemia. Together, these data define METTL3 as a regulator of a chromatin-based pathway that is necessary for maintenance of the leukemic state and identify this enzyme as a potential therapeutic target for acute myeloid leukemia.
- 24Vu, L. P.; Pickering, B. F.; Cheng, Y.; Zaccara, S.; Nguyen, D.; Minuesa, G.; Chou, T.; Chow, A.; Saletore, Y.; MacKay, M.; Schulman, J.; Famulare, C.; Patel, M.; Klimek, V. M.; Garrett-Bakelman, F. E.; Melnick, A.; Carroll, M.; Mason, C. E.; Jaffrey, S. R.; Kharas, M. G. The N6-methyladenosine m6A-forming enzyme METTL3 controls myeloid differentiation of normal hematopoietic and leukemia cells. Nat. Med. 2017, 23 (11), 1369– 1376, DOI: 10.1038/nm.4416[Crossref], [PubMed], [CAS], Google Scholar24https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2sXhsFSku7zM&md5=bbeed4ac8c2dee2baf3ec08e0dec630fThe N6-methyladenosine (m6A)-forming enzyme METTL3 controls myeloid differentiation of normal hematopoietic and leukemia cellsVu, Ly P.; Pickering, Brian F.; Cheng, Yuanming; Zaccara, Sara; Nguyen, Diu; Minuesa, Gerard; Chou, Timothy; Chow, Arthur; Saletore, Yogesh; MacKay, Matthew; Schulman, Jessica; Famulare, Christopher; Patel, Minal; Klimek, Virginia M.; Garrett-Bakelman, Francine E.; Melnick, Ari; Carroll, Martin; Mason, Christopher E.; Jaffrey, Samie R.; Kharas, Michael G.Nature Medicine (New York, NY, United States) (2017), 23 (11), 1369-1376CODEN: NAMEFI; ISSN:1078-8956. (Nature Research)N6-methyladenosine (m6A) is an abundant nucleotide modification in mRNA that is required for the differentiation of mouse embryonic stem cells. However, it remains unknown whether the m6A modification controls the differentiation of normal and/or malignant myeloid hematopoietic cells. Here we show that shRNA-mediated depletion of the m6A-forming enzyme METTL3 in human hematopoietic stem/progenitor cells (HSPCs) promotes cell differentiation, coupled with reduced cell proliferation. Conversely, overexpression of wild-type METTL3, but not of a catalytically inactive form of METTL3, inhibits cell differentiation and increases cell growth. METTL3 mRNA and protein are expressed more abundantly in acute myeloid leukemia (AML) cells than in healthy HSPCs or other types of tumor cells. Furthermore, METTL3 depletion in human myeloid leukemia cell lines induces cell differentiation and apoptosis and delays leukemia progression in recipient mice in vivo. Single-nucleotide-resoln. mapping of m6A coupled with ribosome profiling reveals that m6A promotes the translation of c-MYC, BCL2 and PTEN mRNAs in the human acute myeloid leukemia MOLM-13 cell line. Moreover, loss of METTL3 leads to increased levels of phosphorylated AKT, which contributes to the differentiation-promoting effects of METTL3 depletion. Overall, these results provide a rationale for the therapeutic targeting of METTL3 in myeloid leukemia.
- 25Pendleton, K. E.; Chen, B.; Liu, K.; Hunter, O. V.; Xie, Y.; Tu, B. P.; Conrad, N. K. The U6 snRNA m6A Methyltransferase METTL16 Regulates SAM Synthetase Intron Retention. Cell 2017, 169 (5), 824– 835, DOI: 10.1016/j.cell.2017.05.003[Crossref], [PubMed], [CAS], Google Scholar25https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2sXotlOqtr4%253D&md5=e18b9d1155f4db389d87875a48d50dd6The U6 snRNA m6A methyltransferase METTL16 regulates SAM synthetase intron retentionPendleton, Kathryn E.; Chen, Beibei; Liu, Kuanqing; Hunter, Olga V.; Xie, Yang; Tu, Benjamin P.; Conrad, Nicholas K.Cell (Cambridge, MA, United States) (2017), 169 (5), 824-835.e14CODEN: CELLB5; ISSN:0092-8674. (Cell Press)Maintenance of proper levels of the Me donor S-adenosylmethionine (SAM) is crit. for a wide variety of biol. processes. We demonstrate that the N6-adenosine methyltransferase METTL16 regulates expression of human MAT2A, which encodes the SAM synthetase expressed in most cells. Upon SAM depletion by methionine starvation, cells induce MAT2A expression by enhanced splicing of a retained intron. Induction requires METTL16 and its methylation substrate, a vertebrate conserved hairpin (hp1) in the MAT2A 3' UTR. Increasing METTL16 occupancy on the MAT2A 3' UTR is sufficient to induce efficient splicing. We propose that, under SAM-limiting conditions, METTL16 occupancy on hp1 increases due to inefficient enzymic turnover, which promotes MAT2A splicing. We further show that METTL16 is the long-unknown methyltransferase for the U6 spliceosomal small nuclear RNA (snRNA). These observations suggest that the conserved U6 snRNA methyltransferase evolved an addnl. function in vertebrates to regulate SAM homeostasis.
- 26Bokar, J. A.; Shambaugh, M. E.; Polayes, D.; Matera, A. G.; Rottman, F. M. Purification and cDNA cloning of the AdoMet-binding subunit of the human mRNA (N6-adenosine)-methyltransferase. RNA 1997, 3 (11), 1233– 1247[PubMed], [CAS], Google Scholar26https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaK2sXnsVelsL0%253D&md5=b1733d1237a94608508cfe7e86fb7e6dPurification and cDNA cloning of the AdoMet-binding subunit of the human mRNA (N6-adenosine)-methyltransferaseBokar, Joseph A.; Shambaugh, Mary Eileen; Polayes, Deborah; Matera, A. Gregory; Rottman, Fritz M.RNA (1997), 3 (11), 1233-1247CODEN: RNARFU; ISSN:1355-8382. (Cambridge University Press)The methylation of internal adenosine residues in eukaryotic mRNA, forming N6-methyladenosine (m6A), is catalyzed by a complex multicomponent enzyme. Previous studies suggested that m6A affects the efficiency of mRNA processing or transport, although the mechanism by which this occurs is not known. As a step toward better understanding the mechanism and function of this ubiquitous posttranscriptional modification, the authors have shown that HeLa mRNA (N6-adenosine)-methyltransferase requires at least two sep. protein factors, MT-A and MT-B, and MT-A contains the AdoMet binding site on a 70-kDa subunit (MT-A70). MT-A70 was purified by conventional chromatog. and electrophoresis, and was microsequenced. The peptide sequence was used to design a degenerate oligodeoxynucleotide that in turn was used to isolate the cDNA clone coding for MT-A70 from a HeLa cDNA library. Recombinant MT-A70 was expressed as a fusion protein in bacteria and was used to generate anti-MT-A70 antisera in rabbits. These antisera recognize MT-A70 in HeLa nuclear exts. by western blot and are capable of depleting (N6-adenosine)-methyltransferase activity from HeLa nuclear ext., confirming that MT-A70 is a crit. subunit of (N6-adenosine)-methyltransferase. Northern blot anal. reveals that MT-A70 mRNA is present in a wide variety of human tissues and may undergo alternative splicing. MT-A70 cDNA probe hybridizes to a 2.0-kilobase (kb) polyadenylated RNA isolated from HeLa cells, whereas it hybridizes to two predominant RNA species (approx. 2.0 kb and 3.0 kb) using mRNA isolated from six different human tissues. Anal. of the cDNA sequence indicates that it codes for a 580-amino acid protein with a predicted MW = 65 kDa. The predicted protein contains sequences similar to consensus methylation motifs I and II identified in prokaryotic DNA (N6-adenosine)-methyltransferases, suggesting the functional conservation of peptide motifs. MT-A70 also contains a long region of homol. to the yeast protein SPO8, which is involved in induction of sporulation by an unknown mechanism.
- 27Wiederschain, D.; Wee, S.; Chen, L.; Loo, A.; Yang, G.; Huang, A.; Chen, Y.; Caponigro, G.; Yao, Y.-M.; Lengauer, C.; Sellers, W. R.; Benson, J. D. Single-vector inducible lentiviral RNAi system for oncology target validation. Cell Cycle 2009, 8 (3), 498– 504, DOI: 10.4161/cc.8.3.7701[Crossref], [PubMed], [CAS], Google Scholar27https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD1MXlvFWjtrs%253D&md5=5361e51d2b0e18a834453984bc4667f2Single-vector inducible lentiviral RNAi system for oncology target validationWiederschain, Dmitri; Wee, Susan; Chen, Lin; Loo, Alice; Yang, Guizhi; Huang, Alan; Chen, Yan; Caponigro, Giordano; Yao, Yung-mae; Lengauer, Christoph; Sellers, William R.; Benson, John D.Cell Cycle (2009), 8 (3), 498-504CODEN: CCEYAS; ISSN:1538-4101. (Landes Bioscience)The use of RNA interference (RNAi) has enabled loss-of-function studies in mammalian cancer cells and has hence become crit. for identifying and validating cancer drug targets. Current transient siRNA and stable shRNA systems, however, have limited utility in accurately assessing the cancer dependency due to their short-lived effects and limited in vivo utility, resp. In this study, a single-vector lentiviral, Tet-inducible shRNA system (pLKO-Tet-On) was generated to allow for the rapid generation of multiple stable cell lines with regulatable shRNA expression. We demonstrate the advantages and versatility of this system by targeting two polycomb group proteins, Bmi-1 and Mel-18, in a no. of cancer cell lines. Our data show that pLKO-Tet-On-mediated knockdown is tightly regulated by the inducer tetracycline and its deriv., doxycycline, in a concn.- and time-dependent manner. Furthermore, target gene expression is fully restored upon withdrawal of the inducing agent. An addnl., 17 distinct gene products have been targeted by inducible shRNAs with robust regulation in all cases. Importantly, we functionally validate the ability of the pLKO-Tet-On vector to reversibly silence targeted transcripts in vivo. The versatile and robust inducible lentiviral RNAi system reported herein can therefore serve as a powerful tool to rapidly reveal tumor cell dependence.
- 28Leger, A.; Amaral, P. P.; Pandolfini, L.; Capitanchik, C.; Capraro, F.; Barbieri, I.; Migliori, V.; Luscombe, N. M.; Enright, A. J.; Tzelepis, K.; Ule, J.; Fitzgerald, T.; Birney, E.; Leonardi, T.; Kouzarides, T. RNA modifications detection by comparative Nanopore direct RNA sequencing. bioRxiv 2019, 843136, https://www.biorxiv.org/content/10.1101/843136v1.Google ScholarThere is no corresponding record for this reference.
- 29Doxtader, K. A.; Wang, P.; Scarborough, A. M.; Seo, D.; Conrad, N. K.; Nam, Y. Structural Basis for Regulation of METTL16, an S-Adenosylmethionine Homeostasis Factor. Mol. Cell 2018, 71 (6), 1001– 1011, DOI: 10.1016/j.molcel.2018.07.025[Crossref], [PubMed], [CAS], Google Scholar29https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1cXhs1Kkt7vF&md5=38e7677ae6ccc47726b00d0c795e2e04Structural Basis for Regulation of METTL16, an S-Adenosylmethionine Homeostasis FactorDoxtader, Katelyn A.; Wang, Ping; Scarborough, Anna M.; Seo, Dahee; Conrad, Nicholas K.; Nam, YunsunMolecular Cell (2018), 71 (6), 1001-1011.e4CODEN: MOCEFL; ISSN:1097-2765. (Elsevier Inc.)S-adenosylmethionine (SAM) is an essential metabolite that acts as a cofactor for most methylation events in the cell. The N6-methyladenosine (m6A) methyltransferase METTL16 controls SAM homeostasis by regulating the abundance of SAM synthetase MAT2A mRNA in response to changing intracellular SAM levels. Here we present crystal structures of METTL16 in complex with MAT2A RNA hairpins to uncover crit. mol. mechanisms underlying the regulated activity of METTL16. The METTL16-RNA complex structures reveal at. details of RNA substrates that drive productive methylation by METTL16. In addn., we identify a polypeptide loop in METTL16 near the SAM binding site with an autoregulatory role. We show that mutations that enhance or repress METTL16 activity in vitro correlate with changes in MAT2A mRNA levels in cells. Thus, we demonstrate the structural basis for the specific activity of METTL16 and further suggest the mol. mechanisms by which METTL16 efficiency is tuned to regulate SAM homeostasis.
- 30Yang, D.; Qiao, J.; Wang, G.; Lan, Y.; Li, G.; Guo, X.; Xi, J.; Ye, D.; Zhu, S.; Chen, W.; Jia, W.; Leng, Y.; Wan, X.; Kang, J. N6-Methyladenosine modification of lincRNA 1281 is critically required for mESC differentiation potential. Nucleic Acids Res. 2018, 46 (8), 3906– 3920, DOI: 10.1093/nar/gky130[Crossref], [PubMed], [CAS], Google Scholar30https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1cXitlKhtbnL&md5=507b077d7afa2d0c60c8e2659592fab4N6-methyladenosine modification of lincRNA 1281 is critically required for mESC differentiation potentialYang, Dandan; Qiao, Jing; Wang, Guiying; Lan, Yuanyuan; Li, Guoping; Guo, Xudong; Xi, Jiajie; Ye, Dan; Zhu, Songcheng; Chen, Wen; Jia, Wenwen; Leng, Ye; Wan, Xiaoping; Kang, JiuhongNucleic Acids Research (2018), 46 (8), 3906-3920CODEN: NARHAD; ISSN:1362-4962. (Oxford University Press)Previous studies have revealed the crit. roles of N6-methyladenosine (m6A) modification of mRNA in embryonic stem cells (ESCs), but the biol. function of m6A in large intergenic noncoding RNA (lincRNA) is unknown. Here, we showed that the internal m6A modification of linc1281 mediates a competing endogenous RNA (ceRNA) model to regulate mouse ESC (mESC) differentiation. We demonstrated that loss of linc1281 compromises mESC differentiation and that m6A is highly enriched within linc1281 transcripts. Linc1281 with RRACU m6A sequence motifs, but not an m6A-deficient mutant, restored the phenotype in linc1281-depleted mESCs. Mechanistic analyses revealed that linc1281 ensures mESC identity by sequestering pluripotency-related let-7 family microRNAs (miRNAs), and this RNA-RNA interaction is m6A dependent. Collectively, these findings elucidated the functional roles of linc1281 and its m6A modification in mESCs and identified a novel RNA regulatory mechanism, providing a basis for further exploration of broad RNA epigenetic regulatory patterns.
- 31Zhang, J.; Guo, S.; Piao, H.-Y.; Wang, Y.; Wu, Y.; Meng, X.-Y.; Yang, D.; Zheng, Z.-C.; Zhao, Y. ALKBH5 promotes invasion and metastasis of gastric cancer by decreasing methylation of the lncRNA NEAT1. J. Physiol. Biochem. 2019, 75 (3), 379– 389, DOI: 10.1007/s13105-019-00690-8[Crossref], [PubMed], [CAS], Google Scholar31https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1MXhtlGktbrN&md5=ecab4a9cdbb68eaa311e72fc36471f7dALKBH5 promotes invasion and metastasis of gastric cancer by decreasing methylation of the lncRNA NEAT1Zhang, Jun; Guo, Shuai; Piao, Hai-yan; Wang, Yue; Wu, Yue; Meng, Xiang-yu; Yang, Dong; Zheng, Zhi-chao; Zhao, YanJournal of Physiology and Biochemistry (2019), 75 (3), 379-389CODEN: JPBIF2; ISSN:1138-7548. (Springer)N6-Methyladenosine (m6A) is the most common posttranscriptional modification of RNA and plays crit. roles in cancer pathogenesis. However, the biol. function of long noncoding RNA (lncRNA) methylation remains unclear. As a demethylase, ALKBH5 (alkylation repair homolog protein 5) is involved in mediating methylation reversal. The purpose of this study was to investigate lncRNA m6A modification and its role in gastric cancer (GC). Bioinformatics predicted interactions of ALKBH5 with lncRNAs. Five methods were employed to assess the function of nuclear paraspeckle assembly transcript 1 (NEAT1), including gene silencing, RT-PCR, sepn. of nuclear and cytoplasmic fractions, scrape motility assays, and transwell migration assays. Then, m6A RNA immunopptn. and immunofluorescence were used to detect methylated NEAT1 in GC cells. Rescue assays were performed to define the relationship between NEAT1 and ALKBH5. NEAT1 is a potential binding lncRNA of ALKBH5. NEAT1 was overexpressed in GC cells and tissue. Addnl. expts. confirmed that knockdown of NEAT1 significantly repressed invasion and metastasis of GC cells. ALKBH5 affected the m6A level of NEAT1. The binding of ALKBH5 and NEAT1 influences the expression of EZH2 (a subunit of the polycomb repressive complex) and thus affects GC invasion and metastasis. Our findings indicate a novel mechanism by which ALKBH5 promotes GC invasion and metastasis by demethylating the lncRNA NEAT1. They may be potential therapeutic targets for GC.
- 32Zhou, K. I.; Parisien, M.; Dai, Q.; Liu, N.; Diatchenko, L.; Sachleben, J. R.; Pan, T. N6-Methyladenosine Modification in a Long Noncoding RNA Hairpin Predisposes Its Conformation to Protein Binding. J. Mol. Biol. 2016, 428, 822– 833, DOI: 10.1016/j.jmb.2015.08.021[Crossref], [PubMed], [CAS], Google Scholar32https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2MXhsV2ntr7J&md5=51fd64645634b0f56b234e083f5e5411N6-Methyladenosine Modification in a Long Noncoding RNA Hairpin Predisposes Its Conformation to Protein BindingZhou, Katherine I.; Parisien, Marc; Dai, Qing; Liu, Nian; Diatchenko, Luda; Sachleben, Joseph R.; Pan, TaoJournal of Molecular Biology (2016), 428 (5_Part_A), 822-833CODEN: JMOBAK; ISSN:0022-2836. (Elsevier Ltd.)N6-Methyladenosine (m6A) is a reversible and abundant internal modification of mRNA and long noncoding RNA (lncRNA) with roles in RNA processing, transport, and stability. Although m6A does not preclude Watson-Crick base pairing, the N6-Me group alters the stability of RNA secondary structure. Since changes in RNA structure can affect diverse cellular processes, the influence of m6A on mRNA and lncRNA structure has the potential to be an important mechanism for m6A function in the cell. Indeed, an m6A site in the lncRNA metastasis assocd. lung adenocarcinoma transcript 1 (MALAT1) was recently shown to induce a local change in structure that increases the accessibility of a U5-tract for recognition and binding by heterogeneous nuclear ribonucleoprotein C (HNRNPC). This m6A-dependent regulation of protein binding through a change in RNA structure, termed "m6A-switch", affects transcriptome-wide mRNA abundance and alternative splicing. To further characterize this first example of an m6A-switch in a cellular RNA, we used NMR and Forester resonance energy transfer to demonstrate the effect of m6A on a 32-nucleotide RNA hairpin derived from the m6A-switch in MALAT1. The obsd. imino proton NMR resonances and Forester resonance energy transfer efficiencies suggest that m6A selectively destabilizes the portion of the hairpin stem where the U5-tract is located, increasing the solvent accessibility of the neighboring bases while maintaining the overall hairpin structure. The m6A-modified hairpin has a predisposed conformation that resembles the hairpin conformation in the RNA-HNRNPC complex more closely than the unmodified hairpin. The m6A-induced structural changes in the MALAT1 hairpin can serve as a model for a large family of m6A-switches that mediate the influence of m6A on cellular processes.
- 33Huang, H.; Weng, H.; Zhou, K.; Wu, T.; Zhao, B. S.; Sun, M.; Chen, Z.; Deng, X.; Xiao, G.; Auer, F.; Klemm, L.; Wu, H.; Zuo, Z.; Qin, X.; Dong, Y.; Zhou, Y.; Qin, H.; Tao, S.; Du, J.; Liu, J.; Lu, Z.; Yin, H.; Mesquita, A.; Yuan, C. L.; Hu, Y.-C.; Sun, W.; Su, R.; Dong, L.; Shen, C.; Li, C.; Qing, Y.; Jiang, X.; Wu, X.; Sun, M.; Guan, J.-L.; Qu, L.; Wei, M.; Müschen, M.; Huang, G.; He, C.; Yang, J.; Chen, J. Histone H3 trimethylation at lysine 36 guides m6A RNA modification co-transcriptionally. Nature 2019, 567 (7748), 414– 419, DOI: 10.1038/s41586-019-1016-7[Crossref], [PubMed], [CAS], Google Scholar33https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1MXmslKhurg%253D&md5=11437346726aee249c9cf8782eb4f42fHistone H3 trimethylation at lysine 36 guides m6A RNA modification co-transcriptionallyHuang, Huilin; Weng, Hengyou; Zhou, Keren; Wu, Tong; Zhao, Boxuan Simen; Sun, Mingli; Chen, Zhenhua; Deng, Xiaolan; Xiao, Gang; Auer, Franziska; Klemm, Lars; Wu, Huizhe; Zuo, Zhixiang; Qin, Xi; Dong, Yunzhu; Zhou, Yile; Qin, Hanjun; Tao, Shu; Du, Juan; Liu, Jun; Lu, Zhike; Yin, Hang; Mesquita, Ana; Yuan, Celvie L.; Hu, Yueh-Chiang; Sun, Wenju; Su, Rui; Dong, Lei; Shen, Chao; Li, Chenying; Qing, Ying; Jiang, Xi; Wu, Xiwei; Sun, Miao; Guan, Jun-Lin; Qu, Lianghu; Wei, Minjie; Muschen, Markus; Huang, Gang; He, Chuan; Yang, Jianhua; Chen, JianjunNature (London, United Kingdom) (2019), 567 (7748), 414-419CODEN: NATUAS; ISSN:0028-0836. (Nature Research)DNA and histone modifications have notable effects on gene expression1. Being the most prevalent internal modification in mRNA, the N6-methyladenosine (m6A) mRNA modification is as an important post-transcriptional mechanism of gene regulation2-4 and has crucial roles in various normal and pathol. processes5-12. However, it is unclear how m6A is specifically and dynamically deposited in the transcriptome. Here we report that histone H3 trimethylation at Lys36 (H3K36me3), a marker for transcription elongation, guides m6A deposition globally. We show that m6A modifications are enriched in the vicinity of H3K36me3 peaks, and are reduced globally when cellular H3K36me3 is depleted. Mechanistically, H3K36me3 is recognized and bound directly by METTL14, a crucial component of the m6A methyltransferase complex (MTC), which in turn facilitates the binding of the m6A MTC to adjacent RNA polymerase II, thereby delivering the m6A MTC to actively transcribed nascent RNAs to deposit m6A co-transcriptionally. In mouse embryonic stem cells, phenocopying METTL14 knockdown, H3K36me3 depletion also markedly reduces m6A abundance transcriptome-wide and in pluripotency transcripts, resulting in increased cell stemness. Collectively, our studies reveal the important roles of H3K36me3 and METTL14 in detg. specific and dynamic deposition of m6A in mRNA, and uncover another layer of gene expression regulation that involves crosstalk between histone modification and RNA methylation.
- 34Liu, J.; Dou, X.; Chen, C.; Chen, C.; Liu, C.; Xu, M. M.; Zhao, S.; Shen, B.; Gao, Y.; Han, D.; He, C. N6-methyladenosine of chromosome-associated regulatory RNA regulates chromatin state and transcription. Science 2020, 367 (6477), 580– 586, DOI: 10.1126/science.aay6018[Crossref], [PubMed], [CAS], Google Scholar34https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BB3cXitVGiurw%253D&md5=e2a4f15c7c401604e94665c93960cd01N6-methyladenosine of chromosome-associated regulatory RNA regulates chromatin state and transcriptionLiu, Jun; Dou, Xiaoyang; Chen, Chuanyuan; Chen, Chuan; Liu, Chang; Xu, Meng Michelle; Zhao, Siqi; Shen, Bin; Gao, Yawei; Han, Dali; He, ChuanScience (Washington, DC, United States) (2020), 367 (6477), 580-586CODEN: SCIEAS; ISSN:1095-9203. (American Association for the Advancement of Science)N6-methyladenosine (m6A) regulates stability and translation of mRNA in various biol. processes. In this work, we show that knockout of the m6A writer Mettl3 or the nuclear reader Ythdc1 in mouse embryonic stem cells increases chromatin accessibility and activates transcription in an m6A-dependent manner. We found that METTL3 deposits m6A modifications on chromosome-assocd. regulatory RNAs (carRNAs), including promoter-assocd. RNAs, enhancer RNAs, and repeat RNAs. YTHDC1 facilitates the decay of a subset of these m6A-modified RNAs, esp. elements of the long interspersed element-1 family, through the nuclear exosome targeting-mediated nuclear degrdn. Reducing m6A methylation by METTL3 depletion or site-specific m6A demethylation of selected carRNAs elevates the levels of carRNAs and promotes open chromatin state and downstream transcription. Collectively, our results reveal that m6A on carRNAs can globally tune chromatin state and transcription.
- 35Louloupi, A.; Ntini, E.; Conrad, T.; Ørom, U. A. V. Transient N6-Methyladenosine Transcriptome Sequencing Reveals a Regulatory Role of m6A in Splicing Efficiency. Cell Rep. 2018, 23 (12), 3429– 3437, DOI: 10.1016/j.celrep.2018.05.077[Crossref], [PubMed], [CAS], Google Scholar35https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1cXhtFOkur7M&md5=de3849159013bacdaa2f1b16598fcb9fTransient N-6-Methyladenosine Transcriptome Sequencing Reveals a Regulatory Role of m6A in Splicing EfficiencyLouloupi, Annita; Ntini, Evgenia; Conrad, Thomas; Oerom, Ulf Andersson VangCell Reports (2018), 23 (12), 3429-3437CODEN: CREED8; ISSN:2211-1247. (Cell Press)Splicing efficiency varies among transcripts, and tight control of splicing kinetics is crucial for coordinated gene expression. N-6-methyladenosine (m6A) is the most abundant RNA modification and is involved in regulation of RNA biogenesis and function. The impact of m6A on regulation of RNA splicing kinetics is unknown. Here, we provide a time-resolved high-resoln. assessment of m6A on nascent RNA transcripts and unveil its importance for the control of RNA splicing kinetics. We find that early co-transcriptional m6A deposition near splice junctions promotes fast splicing, while m6A modifications in introns are assocd. with long, slowly processed introns and alternative splicing events. In conclusion, we show that early m6A deposition specifies the fate of transcripts regarding splicing kinetics and alternative splicing.
- 36Mendel, M.; Chen, K.-M.; Homolka, D.; Gos, P.; Pandey, R. R.; McCarthy, A. A.; Pillai, R. S. Methylation of Structured RNA by the m6A Writer METTL16 Is Essential for Mouse Embryonic Development. Mol. Cell 2018, 71 (6), 986– 1000, DOI: 10.1016/j.molcel.2018.08.004[Crossref], [PubMed], [CAS], Google Scholar36https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1cXhs1Kkt7jK&md5=8d5b3d90ae43944528e1bbb87a0e1e14Methylation of Structured RNA by the m6A Writer METTL16 Is Essential for Mouse Embryonic DevelopmentMendel, Mateusz; Chen, Kuan-Ming; Homolka, David; Gos, Pascal; Pandey, Radha Raman; McCarthy, Andrew A.; Pillai, Ramesh S.Molecular Cell (2018), 71 (6), 986-1000.e11CODEN: MOCEFL; ISSN:1097-2765. (Elsevier Inc.)Internal modification of RNAs with N6-methyladenosine (m6A) is a highly conserved means of gene expression control. While the METTL3/METTL14 heterodimer adds this mark on thousands of transcripts in a single-stranded context, the substrate requirements and physiol. roles of the second m6A writer METTL16 remain unknown. Here we describe the crystal structure of human METTL16 to reveal a methyltransferase domain furnished with an extra N-terminal module, which together form a deep-cut groove that is essential for RNA binding. When presented with a random pool of RNAs, METTL16 selects for methylation-structured RNAs where the crit. adenosine is present in a bulge. Mouse 16-cell embryos lacking Mettl16 display reduced mRNA levels of its methylation target, the SAM synthetase Mat2a. The consequence is massive transcriptome dysregulation in ∼64-cell blastocysts that are unfit for further development. This highlights the role of an m6A RNA methyltransferase in facilitating early development via regulation of SAM availability.
- 37Shima, H.; Matsumoto, M.; Ishigami, Y.; Ebina, M.; Muto, A.; Sato, Y.; Kumagai, S.; Ochiai, K.; Suzuki, T.; Igarashi, K. S-Adenosylmethionine Synthesis Is Regulated by Selective N6-Adenosine Methylation and mRNA Degradation Involving METTL16 and YTHDC1. Cell Rep. 2017, 21 (12), 3354– 3363, DOI: 10.1016/j.celrep.2017.11.092[Crossref], [PubMed], [CAS], Google Scholar37https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2sXitVWlsrbE&md5=95ed079e22ae359a395b3d11d58a494bS-Adenosylmethionine Synthesis Is Regulated by Selective N6-Adenosine Methylation and mRNA Degradation Involving METTL16 and YTHDC1Shima, Hiroki; Matsumoto, Mitsuyo; Ishigami, Yuma; Ebina, Masayuki; Muto, Akihiko; Sato, Yuho; Kumagai, Sayaka; Ochiai, Kyoko; Suzuki, Tsutomu; Igarashi, KazuhikoCell Reports (2017), 21 (12), 3354-3363CODEN: CREED8; ISSN:2211-1247. (Cell Press)S-adenosylmethionine (SAM) is an important metabolite as a methyl-group donor in DNA and histone methylation, tuning regulation of gene expression. Appropriate intracellular SAM levels must be maintained, because methyltransferase reaction rates can be limited by SAM availability. In response to SAM depletion, MAT2A, which encodes a ubiquitous mammalian methionine adenosyltransferase isoenzyme, was upregulated through mRNA stabilization. SAM-depletion reduced N6-methyladenosine (m6A) in the 3' UTR of MAT2A. In vitro reactions using recombinant METTL16 revealed multiple, conserved methylation targets in the 3' UTR. Knockdown of METTL16 and the m6A reader YTHDC1 abolished SAM-responsive regulation of MAT2A. Mutations of the target adenine sites of METTL16 within the 3' UTR revealed that these m6As were redundantly required for regulation. MAT2A mRNA methylation by METTL16 is read by YTHDC1, and we suggest that this allows cells to monitor and maintain intracellular SAM levels.
- 38Zhang, L.-S.; Liu, C.; Ma, H.; Dai, Q.; Sun, H.-L.; Luo, G.; Zhang, Z.; Zhang, L.; Hu, L.; Dong, X.; He, C. Transcriptome-wide Mapping of Internal N7-Methylguanosine Methylome in Mammalian mRNA. Mol. Cell 2019, 74 (6), 1304– 1316, DOI: 10.1016/j.molcel.2019.03.036[Crossref], [PubMed], [CAS], Google Scholar38https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1MXosVSgtbs%253D&md5=7031c6e2fa681366856d66a9a843c7f8Transcriptome-wide Mapping of Internal N7-Methylguanosine Methylome in Mammalian mRNAZhang, Li-Sheng; Liu, Chang; Ma, Honghui; Dai, Qing; Sun, Hui-Lung; Luo, Guanzheng; Zhang, Zijie; Zhang, Linda; Hu, Lulu; Dong, Xueyang; He, ChuanMolecular Cell (2019), 74 (6), 1304-1316.e8CODEN: MOCEFL; ISSN:1097-2765. (Elsevier Inc.)N7-methylguanosine (m7G) is a pos. charged, essential modification at the 5' cap of eukaryotic mRNA, regulating mRNA export, translation, and splicing. M7G also occurs internally within tRNA and rRNA, but its existence and distribution within eukaryotic mRNA remain to be investigated. Here, we show the presence of internal m7G sites within mammalian mRNA. We then performed transcriptome-wide profiling of internal m7G methylome using m7G-MeRIP sequencing (MeRIP-seq). To map this modification at base resoln., we developed a chem.-assisted sequencing approach that selectively converts internal m7G sites into abasic sites, inducing misincorporation at these sites during reverse transcription. This base-resoln. m7G-seq enabled transcriptome-wide mapping of m7G in human tRNA and mRNA, revealing distribution features of the internal m7G methylome in human cells. We also identified METTL1 as a methyltransferase that installs a subset of m7G within mRNA and showed that internal m7G methylation could affect mRNA translation.
- 39Lee, S.-H.; Singh, I.; Tisdale, S.; Abdel-Wahab, O.; Leslie, C. S.; Mayr, C. Widespread intronic polyadenylation inactivates tumour suppressor genes in leukaemia. Nature 2018, 561 (7721), 127– 131, DOI: 10.1038/s41586-018-0465-8[Crossref], [PubMed], [CAS], Google Scholar39https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1cXhsF2nsrjJ&md5=cb45b01f216beec2c3d75e3514f74721Widespread intronic polyadenylation inactivates tumour suppressor genes in leukemiaLee, Shih-Han; Singh, Irtisha; Tisdale, Sarah; Abdel-Wahab, Omar; Leslie, Christina S.; Mayr, ChristineNature (London, United Kingdom) (2018), 561 (7721), 127-131CODEN: NATUAS; ISSN:0028-0836. (Nature Research)DNA mutations are known cancer drivers. Here we investigated whether mRNA events that are upregulated in cancer can functionally mimic the outcome of genetic alterations. RNA sequencing or 3'-end sequencing techniques were applied to normal and malignant B cells from 59 patients with chronic lymphocytic leukemia (CLL)1-3. We discovered widespread upregulation of truncated mRNAs and proteins in primary CLL cells that were not generated by genetic alterations but instead occurred by intronic polyadenylation. Truncated mRNAs caused by intronic polyadenylation were recurrent (n = 330) and predominantly affected genes with tumor-suppressive functions. The truncated proteins generated by intronic polyadenylation often lack the tumor-suppressive functions of the corresponding full-length proteins (such as DICER and FOXN3), and several even acted in an oncogenic manner (such as CARD11, MGA and CHST11). In CLL, the inactivation of tumor-suppressor genes by aberrant mRNA processing is substantially more prevalent than the functional loss of such genes through genetic events. We further identified new candidate tumor-suppressor genes that are inactivated by intronic polyadenylation in leukemia and by truncating DNA mutations in solid tumors4,5. These genes are understudied in cancer, as their overall mutation rates are lower than those of well-known tumor-suppressor genes. Our findings show the need to go beyond genomic analyses in cancer diagnostics, as mRNA events that are silent at the DNA level are widespread contributors to cancer pathogenesis through the inactivation of tumor-suppressor genes.
- 40Singh, I.; Lee, S.-H.; Sperling, A. S.; Samur, M. K.; Tai, Y.-T.; Fulciniti, M.; Munshi, N. C.; Mayr, C.; Leslie, C. S. Widespread intronic polyadenylation diversifies immune cell transcriptomes. Nat. Commun. 2018, 9 (1), 1716, DOI: 10.1038/s41467-018-04112-z[Crossref], [PubMed], [CAS], Google Scholar40https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A280%3ADC%252BC1MjosVCguw%253D%253D&md5=b5e11fe75fbd9eb1011a636dc31ec3d5Widespread intronic polyadenylation diversifies immune cell transcriptomesSingh Irtisha; Leslie Christina S; Singh Irtisha; Lee Shih-Han; Mayr Christine; Sperling Adam S; Samur Mehmet K; Tai Yu-Tzu; Fulciniti Mariateresa; Munshi Nikhil CNature communications (2018), 9 (1), 1716 ISSN:.Alternative cleavage and polyadenylation (ApA) is known to alter untranslated region (3'UTR) length but can also recognize intronic polyadenylation (IpA) signals to generate transcripts that lose part or all of the coding region. We analyzed 46 3'-seq and RNA-seq profiles from normal human tissues, primary immune cells, and multiple myeloma (MM) samples and created an atlas of 4927 high-confidence IpA events represented in these cell types. IpA isoforms are widely expressed in immune cells, differentially used during B-cell development or in different cellular environments, and can generate truncated proteins lacking C-terminal functional domains. This can mimic ectodomain shedding through loss of transmembrane domains or alter the binding specificity of proteins with DNA-binding or protein-protein interaction domains. MM cells display a striking loss of IpA isoforms expressed in plasma cells, associated with shorter progression-free survival and impacting key genes in MM biology and response to lenalidomide.
- 41Jung, H.; Lee, D.; Lee, J.; Park, D.; Kim, Y. J.; Park, W.-Y.; Hong, D.; Park, P. J.; Lee, E. Intron retention is a widespread mechanism of tumor-suppressor inactivation. Nat. Genet. 2015, 47 (11), 1242– 1248, DOI: 10.1038/ng.3414[Crossref], [PubMed], [CAS], Google Scholar41https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2MXhs1Wls7nE&md5=3066f0d5ad036a5219f0fe69703b9c86Intron retention is a widespread mechanism of tumor-suppressor inactivationJung, Hyunchul; Lee, Donghoon; Lee, Jongkeun; Park, Donghyun; Kim, Yeon Jeong; Park, Woong-Yang; Hong, Dongwan; Park, Peter J.; Lee, EunjungNature Genetics (2015), 47 (11), 1242-1248CODEN: NGENEC; ISSN:1061-4036. (Nature Publishing Group)A substantial fraction of disease-causing mutations are pathogenic through aberrant splicing. Although genome profiling studies have identified somatic single-nucleotide variants (SNVs) in cancer, the extent to which these variants trigger abnormal splicing has not been systematically examd. Here we analyzed RNA sequencing and exome data from 1,812 patients with cancer and identified ∼900 somatic exonic SNVs that disrupt splicing. At least 163 SNVs, including 31 synonymous ones, were shown to cause intron retention or exon skipping in an allele-specific manner, with ∼70% of the SNVs occurring on the last base of exons. Notably, SNVs causing intron retention were enriched in tumor suppressors, and 97% of these SNVs generated a premature termination codon, leading to loss of function through nonsense-mediated decay or truncated protein. We also characterized the genomic features predictive of such splicing defects. Overall, this work demonstrates that intron retention is a common mechanism of tumor-suppressor inactivation.
- 42Kopp, F.; Mendell, J. T. Functional Classification and Experimental Dissection of Long Noncoding RNAs. Cell 2018, 172 (3), 393– 407, DOI: 10.1016/j.cell.2018.01.011[Crossref], [PubMed], [CAS], Google Scholar42https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1cXislyisLc%253D&md5=d6a6a0be4ee524f32b22941d6ca509bfFunctional classification and experimental dissection of long noncoding RNAsKopp, Florian; Mendell, Joshua T.Cell (Cambridge, MA, United States) (2018), 172 (3), 393-407CODEN: CELLB5; ISSN:0092-8674. (Cell Press)A review. Over the last decade, it has been increasingly demonstrated that the genomes of many species are pervasively transcribed, resulting in the prodn. of numerous long noncoding RNAs (lncRNAs). At the same time, it is now appreciated that many types of DNA regulatory elements, such as enhancers and promoters, regularly initiate bi-directional transcription. Thus, discerning functional noncoding transcripts from a vast transcriptome is a paramount priority, and challenge, for the lncRNA field. In this review, we aim to provide a conceptual and exptl. framework for classifying and elucidating lncRNA function. We categorize lncRNA loci into those that regulate gene expression in cis vs. those that perform functions in trans and propose an exptl. approach to dissect lncRNA activity based on these classifications. These strategies to further understand lncRNAs promise to reveal new and unanticipated biol. with great potential to advance our understanding of normal physiol. and disease.
- 43Freitas, A. A. Comprehensible classification models: a position paper. SIGKDD Explor. Newsl. 2014, 15 (1), 1– 10, DOI: 10.1145/2594473.2594475
- 44Tzelepis, K.; Koike-Yusa, H.; De Braekeleer, E.; Li, Y.; Metzakopian, E.; Dovey, O. M.; Mupo, A.; Grinkevich, V.; Li, M.; Mazan, M.; Gozdecka, M.; Ohnishi, S.; Cooper, J.; Patel, M.; McKerrell, T.; Chen, B.; Domingues, A. F.; Gallipoli, P.; Teichmann, S.; Ponstingl, H.; McDermott, U.; Saez-Rodriguez, J.; Huntly, B. J. P.; Iorio, F.; Pina, C.; Vassiliou, G. S.; Yusa, K. A CRISPR Dropout Screen Identifies Genetic Vulnerabilities and Therapeutic Targets in Acute Myeloid Leukemia. Cell Rep. 2016, 17 (4), 1193– 1205, DOI: 10.1016/j.celrep.2016.09.079[Crossref], [PubMed], [CAS], Google Scholar44https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC28XhslSntLjM&md5=8b891343b0fb43fd6cf39d8ed8ee29c4A CRISPR Dropout Screen Identifies Genetic Vulnerabilities and Therapeutic Targets in Acute Myeloid LeukemiaTzelepis, Konstantinos; Koike-Yusa, Hiroko; De Braekeleer, Etienne; Li, Yilong; Metzakopian, Emmanouil; Dovey, Oliver M.; Mupo, Annalisa; Grinkevich, Vera; Li, Meng; Mazan, Milena; Gozdecka, Malgorzata; Ohnishi, Shuhei; Cooper, Jonathan; Patel, Miten; McKerrell, Thomas; Chen, Bin; Domingues, Ana Filipa; Gallipoli, Paolo; Teichmann, Sarah; Ponstingl, Hannes; McDermott, Ultan; Saez-Rodriguez, Julio; Huntly, Brian J. P.; Iorio, Francesco; Pina, Cristina; Vassiliou, George S.; Yusa, KosukeCell Reports (2016), 17 (4), 1193-1205CODEN: CREED8; ISSN:2211-1247. (Cell Press)Acute myeloid leukemia (AML) is an aggressive cancer with a poor prognosis, for which mainstream treatments have not changed for decades. To identify addnl. therapeutic targets in AML, we optimize a genome-wide clustered regularly interspaced short palindromic repeats (CRISPR) screening platform and use it to identify genetic vulnerabilities in AML cells. We identify 492 AML-specific cell-essential genes, including several established therapeutic targets such as DOT1L, BCL2, and MEN1, and many other genes including clin. actionable candidates. We validate selected genes using genetic and pharmacol. inhibition, and chose KAT2A as a candidate for downstream study. KAT2A inhibition demonstrated anti-AML activity by inducing myeloid differentiation and apoptosis, and suppressed the growth of primary human AMLs of diverse genotypes while sparing normal hemopoietic stem-progenitor cells. Our results propose that KAT2A inhibition should be investigated as a therapeutic strategy in AML and provide a large no. of genetic vulnerabilities of this leukemia that can be pursued in downstream studies.
- 45Dobin, A.; Davis, C. A.; Schlesinger, F.; Drenkow, J.; Zaleski, C.; Jha, S.; Batut, P.; Chaisson, M.; Gingeras, T. R. STAR: ultrafast universal RNA-seq aligner. Bioinformatics 2013, 29 (1), 15– 21, DOI: 10.1093/bioinformatics/bts635[Crossref], [PubMed], [CAS], Google Scholar45https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC38XhvV2gsbnF&md5=9b8cfeabbb51258d6c450d4fe928052fSTAR: ultrafast universal RNA-seq alignerDobin, Alexander; Davis, Carrie A.; Schlesinger, Felix; Drenkow, Jorg; Zaleski, Chris; Jha, Sonali; Batut, Philippe; Chaisson, Mark; Gingeras, Thomas R.Bioinformatics (2013), 29 (1), 15-21CODEN: BOINFP; ISSN:1367-4803. (Oxford University Press)Motivation: Accurate alignment of high-throughput RNA-seq data is a challenging and yet unsolved problem because of the non-contiguous transcript structure, relatively short read lengths and constantly increasing throughput of the sequencing technologies. Currently available RNA-seq aligners suffer from high mapping error rates, low mapping speed, read length limitation and mapping biases. Results: To align our large (>80 billon reads) ENCODE Transcriptome RNA-seq dataset, we developed the Spliced Transcripts Alignment to a Ref. (STAR) software based on a previously undescribed RNA-seq alignment algorithm that uses sequential max. mappable seed search in uncompressed suffix arrays followed by seed clustering and stitching procedure. STAR outperforms other aligners by a factor of >50 in mapping speed, aligning to the human genome 550 million 2 × 76 bp paired-end reads per h on a modest 12-core server, while at the same time improving alignment sensitivity and precision. In addn. to unbiased de novo detection of canonical junctions, STAR can discover non-canonical splices and chimeric (fusion) transcripts, and is also capable of mapping full-length RNA sequences. Using Roche 454 sequencing of reverse transcription polymerase chain reaction amplicons, we exptl. validated 1960 novel intergenic splice junctions with an 80-90% success rate, corroborating the high precision of the STAR mapping strategy.
- 46Ramírez, F.; Ryan, D. P.; Grüning, B.; Bhardwaj, V.; Kilpert, F.; Richter, A. S.; Heyne, S.; Dündar, F.; Manke, T. deepTools2: a next generation web server for deep-sequencing data analysis. Nucleic Acids Res. 2016, 44 (W1), W160– W165, DOI: 10.1093/nar/gkw257[Crossref], [PubMed], [CAS], Google Scholar46https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2sXhtV2itrfI&md5=d4be278c28c75bdaea672a9420efef8fdeepTools2: a next generation web server for deep-sequencing data analysisRamirez, Fidel; Ryan, Devon P.; Gruening, Bjoern; Bhardwaj, Vivek; Kilpert, Fabian; Richter, Andreas S.; Heyne, Steffen; Duendar, Friederike; Manke, ThomasNucleic Acids Research (2016), 44 (W1), W160-W165CODEN: NARHAD; ISSN:0305-1048. (Oxford University Press)We present an update to our Galaxy-based web server for processing and visualizing deeply sequenced data. Its core tool set, deepTools, allows users to perform complete bioinformatic workflows ranging from quality controls and normalizations of aligned reads to integrative analyses, including clustering and visualization approaches. Since we first described our deepTools Galaxy server in 2014, we have implemented new solns. for many requests from the community and our users. Here, we introduce significant enhancements and new tools to further improve data visualization and interpretation. DeepTools continue to be open to all users and freely available as a web service. The new deepTools2 suite can be easily deployed within any Galaxy framework via the toolshed repository, and we also provide source code for command line usage under Linux and Mac OS X. A public and documented API for access to deepTools functionality is also available.
- 47Quinlan, A. R.; Hall, I. M. BEDTools: a flexible suite of utilities for comparing genomic features. Bioinformatics 2010, 26 (6), 841– 842, DOI: 10.1093/bioinformatics/btq033[Crossref], [PubMed], [CAS], Google Scholar47https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3cXivFGkurc%253D&md5=508a4f647b8c205fdac8358528f3e835BEDTools: a flexible suite of utilities for comparing genomic featuresQuinlan, Aaron R.; Hall, Ira M.Bioinformatics (2010), 26 (6), 841-842CODEN: BOINFP; ISSN:1367-4803. (Oxford University Press)Testing for correlations between different sets of genomic features is a fundamental task in genomics research. However, searching for overlaps between features with existing web-based methods is complicated by the massive datasets that are routinely produced with current sequencing technologies. Fast and flexible tools are therefore required to ask complex questions of these data in an efficient manner. This article introduces a new software suite for the comparison, manipulation and annotation of genomic features in Browser Extensible Data (BED) and General Feature Format (GFF) format. BEDTools also supports the comparison of sequence alignments in BAM format to both BED and GFF features. The tools are extremely efficient and allow the user to compare large datasets (e.g. next-generation sequencing data) with both public and custom genome annotation tracks. BEDTools can be combined with one another as well as with std. UNIX commands, thus facilitating routine genomics tasks as well as pipelines that can quickly answer intricate questions of large genomic datasets.
- 48Li, H.; Handsaker, B.; Wysoker, A.; Fennell, T.; Ruan, J.; Homer, N.; Marth, G.; Abecasis, G.; Durbin, R.; Genome Project Data Processing, S. The Sequence Alignment/Map format and SAMtools. Bioinformatics 2009, 25 (16), 2078– 2079, DOI: 10.1093/bioinformatics/btp352[Crossref], [PubMed], [CAS], Google Scholar48https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD1MXpslertr8%253D&md5=1ab7714968487a35cce7f81b751a0b1aThe Sequence Alignment/Map format and SAMtoolsLi, Heng; Handsaker, Bob; Wysoker, Alec; Fennell, Tim; Ruan, Jue; Homer, Nils; Marth, Gabor; Abecasis, Goncalo; Durbin, RichardBioinformatics (2009), 25 (16), 2078-2079CODEN: BOINFP; ISSN:1367-4803. (Oxford University Press)Summary: The Sequence Alignment/Map (SAM) format is a generic alignment format for storing read alignments against ref. sequences, supporting short and long reads (up to 128 Mbp) produced by different sequencing platforms. It is flexible in style, compact in size, efficient in random access and is the format in which alignments from the 1000 Genomes Project are released. SAMtools implements various utilities for post-processing alignments in the SAM format, such as indexing, variant caller and alignment viewer, and thus provides universal tools for processing read alignments. Availability: http://samtools.sourceforge.net Contact: [email protected]
- 49Zhang, Y.; Liu, T.; Meyer, C. A.; Eeckhoute, J.; Johnson, D. S.; Bernstein, B. E.; Nussbaum, C.; Myers, R. M.; Brown, M.; Li, W.; Liu, X. S. Model-based Analysis of ChIP-Seq (MACS). Genome Biol. 2008, 9 (9), R137, DOI: 10.1186/gb-2008-9-9-r137
- 50Machanick, P.; Bailey, T. L. MEME-ChIP: motif analysis of large DNA datasets. Bioinformatics 2011, 27 (12), 1696– 1697, DOI: 10.1093/bioinformatics/btr189[Crossref], [PubMed], [CAS], Google Scholar50https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3MXntFGkurw%253D&md5=8868fb42f9aca7fb2fc85c3aefdefaafMEME-ChIP: motif analysis of large DNA datasetsMachanick, Philip; Bailey, Timothy L.Bioinformatics (2011), 27 (12), 1696-1697CODEN: BOINFP; ISSN:1367-4803. (Oxford University Press)Motivation: Advances in high-throughput sequencing have resulted in rapid growth in large, high-quality datasets including those arising from transcription factor (TF) ChIP-seq expts. While there are many existing tools for discovering TF binding site motifs in such datasets, most web-based tools cannot directly process such large datasets. Results: The MEME-ChIP web service is designed to analyze ChIP-seq peak regions'-short genomic regions surrounding declared ChIP-seq peaks'. Given a set of genomic regions, it performs (i) ab initio motif discovery, (ii) motif enrichment anal., (iii) motif visualization, (iv) binding affinity anal. and (v) motif identification. It runs two complementary motif discovery algorithms on the input data-MEME and DREME-and uses the motifs they discover in subsequent visualization, binding affinity and identification steps. MEME-ChIP also performs motif enrichment anal. using the AME algorithm, which can detect very low levels of enrichment of binding sites for TFs with known DNA-binding motifs. Importantly, unlike with the MEME web service, there is no restriction on the size or no. of uploaded sequences, allowing very large ChIP-seq datasets to be analyzed. The analyses performed by MEME-ChIP provide the user with a varied view of the binding and regulatory activity of the ChIP-ed TF, as well as the possible involvement of other DNA-binding TFs.
Supporting Information
ARTICLE SECTIONSThe Supporting Information is available free of charge at https://pubs.acs.org/doi/10.1021/acscentsci.0c01094.
Putative mass spectra peaks for the 11-mer after 2 hour degradation and for the functionalized and BCS-quenched 11-mer after 14 hour degradation, detected RNA species, oligomers used for the in vitro study, list of primers and gRNAs, analysis of propargylated and non-propargylated RNA oligomers degradation by click-degrader, predicted structures of oligomers used, analyses of CTRL and Prop oligomers, analysis of mRNA and lncRNA species, examples of intronic peak snapshots, analyses of METTL3- and METTL16-dependent peaks, comparison of methylated mRNAs determined via meCLICK-Seq and m7G-Seq, analysis of MeCLICK-Seq peaks and IPA sites, mass spectra of functionalized 11-mer species, and chemical synthesis and characterization including NMR spectra (PDF)
METTL3 and METTL16 mRNA substrates determined via meCLICK-Seq (TXT)
Results of a miCLIP study of m6A in MOLM13 cells (XLSX)
METTL3 and METTL16 lncRNA substrates determined via meCLICK-Seq (TXT)
METTL13 and METTL16-dependent intronic/intergenic peaks determined via meCLICK-Seq (XLSX)
Methylated mRNA species determined via meCLICK-Seq with an overlap with m7G-Seq study (XLSX)
Intronic and intergenic click-degrader sensitive RNA peaks with an overlap with m7G-Seq study (XLSX)
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