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Yustis JC, Devoucoux M, Côté J. The Functional Relationship Between RNA Splicing and the Chromatin Landscape. J Mol Biol 2024; 436:168614. [PMID: 38762032 DOI: 10.1016/j.jmb.2024.168614] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2024] [Revised: 04/27/2024] [Accepted: 05/13/2024] [Indexed: 05/20/2024]
Abstract
Chromatin is a highly regulated and dynamic structure that has been shown to play an essential role in transcriptional and co-transcriptional regulation. In the context of RNA splicing, early evidence suggested a loose connection between the chromatin landscape and splicing. More recently, it has been shown that splicing occurs in a co-transcriptional manner, meaning that the splicing process occurs in the context of chromatin. Experimental and computational evidence have also shown that chromatin dynamics can influence the splicing process and vice versa. However, much of this evidence provides mainly correlative relationships between chromatin and splicing with just a few concrete examples providing defined molecular mechanisms by which these two processes are functionally related. Nevertheless, it is clear that chromatin and RNA splicing are tightly interconnected to one another. In this review, we highlight the current state of knowledge of the relationship between chromatin and splicing.
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Affiliation(s)
- Juan-Carlos Yustis
- St-Patrick Research Group in Basic Oncology, Laval University Cancer Research Center, Oncology Division of the CHU de Québec-Université Laval Research Center, Quebec City, Quebec G1R 3S3, Canada
| | - Maëva Devoucoux
- St-Patrick Research Group in Basic Oncology, Laval University Cancer Research Center, Oncology Division of the CHU de Québec-Université Laval Research Center, Quebec City, Quebec G1R 3S3, Canada
| | - Jacques Côté
- St-Patrick Research Group in Basic Oncology, Laval University Cancer Research Center, Oncology Division of the CHU de Québec-Université Laval Research Center, Quebec City, Quebec G1R 3S3, Canada.
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2
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Zhang X, Xu J, Hu J, Zhang S, Hao Y, Zhang D, Qian H, Wang D, Fu XD. Cockayne Syndrome Linked to Elevated R-Loops Induced by Stalled RNA Polymerase II during Transcription Elongation. Nat Commun 2024; 15:6031. [PMID: 39019869 PMCID: PMC11255242 DOI: 10.1038/s41467-024-50298-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Accepted: 07/04/2024] [Indexed: 07/19/2024] Open
Abstract
Mutations in the Cockayne Syndrome group B (CSB) gene cause cancer in mice, but premature aging and severe neurodevelopmental defects in humans. CSB, a member of the SWI/SNF family of chromatin remodelers, plays diverse roles in regulating gene expression and transcription-coupled nucleotide excision repair (TC-NER); however, these functions do not explain the distinct phenotypic differences observed between CSB-deficient mice and humans. During investigating Cockayne Syndrome-associated genome instability, we uncover an intrinsic mechanism that involves elongating RNA polymerase II (RNAPII) undergoing transient pauses at internal T-runs where CSB is required to propel RNAPII forward. Consequently, CSB deficiency retards RNAPII elongation in these regions, and when coupled with G-rich sequences upstream, exacerbates genome instability by promoting R-loop formation. These R-loop prone motifs are notably abundant in relatively long genes related to neuronal functions in the human genome, but less prevalent in the mouse genome. These findings provide mechanistic insights into differential impacts of CSB deficiency on mice versus humans and suggest that the manifestation of the Cockayne Syndrome phenotype in humans results from the progressive evolution of mammalian genomes.
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Affiliation(s)
- Xuan Zhang
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, CA, USA
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA, USA
| | - Jun Xu
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA, USA
- Genetics and Metabolism Department, The Children's Hospital, School of Medicine, Zhejiang University, National Clinical Research Center for Child Health, Hangzhou, China
- The Institute of Translational Medicine, School of Medicine, Zhejiang University, Hangzhou, China
| | - Jing Hu
- Sichuan Provincial Key Laboratory for Human Disease Gene Study, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China
| | - Sitao Zhang
- National Institute of Biological Sciences,7 Science Park Road, Beijing, China
| | - Yajing Hao
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, CA, USA
- China National Center for Bioinformation, Beijing, China
- Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, 100049, Beijing, China
| | - Dongyang Zhang
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA, USA
| | - Hao Qian
- Sichuan Provincial Key Laboratory for Human Disease Gene Study, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China
| | - Dong Wang
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, CA, USA.
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA, USA.
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA, USA.
| | - Xiang-Dong Fu
- Westlake Laboratory of Life Sciences and Biomedicine, School of Life Sciences and School of Medicine, Westlake University, Hangzhou, Zhejiang, China.
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3
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Shine M, Gordon J, Schärfen L, Zigackova D, Herzel L, Neugebauer KM. Co-transcriptional gene regulation in eukaryotes and prokaryotes. Nat Rev Mol Cell Biol 2024; 25:534-554. [PMID: 38509203 PMCID: PMC11199108 DOI: 10.1038/s41580-024-00706-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/19/2024] [Indexed: 03/22/2024]
Abstract
Many steps of RNA processing occur during transcription by RNA polymerases. Co-transcriptional activities are deemed commonplace in prokaryotes, in which the lack of membrane barriers allows mixing of all gene expression steps, from transcription to translation. In the past decade, an extraordinary level of coordination between transcription and RNA processing has emerged in eukaryotes. In this Review, we discuss recent developments in our understanding of co-transcriptional gene regulation in both eukaryotes and prokaryotes, comparing methodologies and mechanisms, and highlight striking parallels in how RNA polymerases interact with the machineries that act on nascent RNA. The development of RNA sequencing and imaging techniques that detect transient transcription and RNA processing intermediates has facilitated discoveries of transcription coordination with splicing, 3'-end cleavage and dynamic RNA folding and revealed physical contacts between processing machineries and RNA polymerases. Such studies indicate that intron retention in a given nascent transcript can prevent 3'-end cleavage and cause transcriptional readthrough, which is a hallmark of eukaryotic cellular stress responses. We also discuss how coordination between nascent RNA biogenesis and transcription drives fundamental aspects of gene expression in both prokaryotes and eukaryotes.
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Affiliation(s)
- Morgan Shine
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Jackson Gordon
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Leonard Schärfen
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Dagmar Zigackova
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Lydia Herzel
- Department of Biology, Chemistry, and Pharmacy, Freie Universität Berlin, Berlin, Germany.
| | - Karla M Neugebauer
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA.
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4
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Moyung K, Li Y, Hartemink AJ, MacAlpine DM. Genome-wide nucleosome and transcription factor responses to genetic perturbations reveal chromatin-mediated mechanisms of transcriptional regulation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.24.595391. [PMID: 38826400 PMCID: PMC11142231 DOI: 10.1101/2024.05.24.595391] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2024]
Abstract
Epigenetic mechanisms contribute to gene regulation by altering chromatin accessibility through changes in transcription factor (TF) and nucleosome occupancy throughout the genome. Despite numerous studies focusing on changes in gene expression, the intricate chromatin-mediated regulatory code remains largely unexplored on a comprehensive scale. We address this by employing a factor-agnostic, reverse-genetics approach that uses MNase-seq to capture genome-wide TF and nucleosome occupancies in response to the individual deletion of 201 transcriptional regulators in Saccharomyces cerevisiae, thereby assaying nearly one million mutant-gene interactions. We develop a principled approach to identify and quantify chromatin changes genome-wide, observing differences in TF and nucleosome occupancy that recapitulate well-established pathways identified by gene expression data. We also discover distinct chromatin signatures associated with the up- and downregulation of genes, and use these signatures to reveal regulatory mechanisms previously unexplored in expression-based studies. Finally, we demonstrate that chromatin features are predictive of transcriptional activity and leverage these features to reconstruct chromatin-based transcriptional regulatory networks. Overall, these results illustrate the power of an approach combining genetic perturbation with high-resolution epigenomic profiling; the latter enables a close examination of the interplay between TFs and nucleosomes genome-wide, providing a deeper, more mechanistic understanding of the complex relationship between chromatin organization and transcription.
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Affiliation(s)
- Kevin Moyung
- Program in Computational Biology and Bioinformatics, Duke University, Durham, NC 27708
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC 27710
| | - Yulong Li
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC 27710
- Department of Computer Science, Duke University, Durham, NC 27708
| | - Alexander J. Hartemink
- Program in Computational Biology and Bioinformatics, Duke University, Durham, NC 27708
- Department of Computer Science, Duke University, Durham, NC 27708
| | - David M. MacAlpine
- Program in Computational Biology and Bioinformatics, Duke University, Durham, NC 27708
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC 27710
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5
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Ren L, Ma W, Wang Y. Predicting RNA polymerase II transcriptional elongation pausing and associated histone code. Brief Bioinform 2024; 25:bbae246. [PMID: 38783706 PMCID: PMC11116834 DOI: 10.1093/bib/bbae246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Revised: 04/12/2024] [Accepted: 05/07/2024] [Indexed: 05/25/2024] Open
Abstract
RNA Polymerase II (Pol II) transcriptional elongation pausing is an integral part of the dynamic regulation of gene transcription in the genome of metazoans. It plays a pivotal role in many vital biological processes and disease progression. However, experimentally measuring genome-wide Pol II pausing is technically challenging and the precise governing mechanism underlying this process is not fully understood. Here, we develop RP3 (RNA Polymerase II Pausing Prediction), a network regularized logistic regression machine learning method, to predict Pol II pausing events by integrating genome sequence, histone modification, gene expression, chromatin accessibility, and protein-protein interaction data. RP3 can accurately predict Pol II pausing in diverse cellular contexts and unveil the transcription factors that are associated with the Pol II pausing machinery. Furthermore, we utilize a forward feature selection framework to systematically identify the combination of histone modification signals associated with Pol II pausing. RP3 is freely available at https://github.com/AMSSwanglab/RP3.
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Affiliation(s)
- Lixin Ren
- School of Mathematics and Physics, University of Science and Technology Beijing, 30 Xueyuan Road, Haidian District, Beijing 100083, China
| | - Wanbiao Ma
- School of Mathematics and Physics, University of Science and Technology Beijing, 30 Xueyuan Road, Haidian District, Beijing 100083, China
| | - Yong Wang
- CEMS, NCMIS, MDIS, Academy of Mathematics and Systems Science, National Center for Mathematics and Interdisciplinary Sciences, Chinese Academy of Sciences, 55 Zhongguancun East Road, Haidian District, Beijing 100190, China
- School of Mathematical Sciences, University of Chinese Academy of Sciences, 19A Yuquan Road, Shijingshan District, Beijing 100049, China
- Center for Excellence in Animal Evolution and Genetics, Chinese Academy of Sciences, 32 Jiaochang Donglu, Wuhua District, Kunming 650223, China
- Key Laboratory of Systems Biology, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 1 Xiangshan Zhi Nong, West Lake District, Hangzhou 330106, China
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6
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Koludarova L, Battersby BJ. Mitochondrial protein synthesis quality control. Hum Mol Genet 2024; 33:R53-R60. [PMID: 38280230 PMCID: PMC11112378 DOI: 10.1093/hmg/ddae012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Accepted: 01/05/2023] [Indexed: 01/29/2024] Open
Abstract
Human mitochondrial DNA is one of the most simplified cellular genomes and facilitates compartmentalized gene expression. Within the organelle, there is no physical barrier to separate transcription and translation, nor is there evidence that quality control surveillance pathways are active to prevent translation on faulty mRNA transcripts. Mitochondrial ribosomes synthesize 13 hydrophobic proteins that require co-translational insertion into the inner membrane of the organelle. To maintain the integrity of the inner membrane, which is essential for organelle function, requires responsive quality control mechanisms to recognize aberrations in protein synthesis. In this review, we explore how defects in mitochondrial protein synthesis can arise due to the culmination of inherent mistakes that occur throughout the steps of gene expression. In turn, we examine the stepwise series of quality control processes that are needed to eliminate any mistakes that would perturb organelle homeostasis. We aim to provide an integrated view on the quality control mechanisms of mitochondrial protein synthesis and to identify promising avenues for future research.
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Affiliation(s)
- Lidiia Koludarova
- Institute of Biotechnology, HiLIFE, University of Helsinki, Helsinki 00014, Finland
| | - Brendan J Battersby
- Institute of Biotechnology, HiLIFE, University of Helsinki, Helsinki 00014, Finland
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7
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Merens HE, Choquet K, Baxter-Koenigs AR, Churchman LS. Timing is everything: advances in quantifying splicing kinetics. Trends Cell Biol 2024:S0962-8924(24)00070-9. [PMID: 38777664 DOI: 10.1016/j.tcb.2024.03.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Revised: 03/26/2024] [Accepted: 03/27/2024] [Indexed: 05/25/2024]
Abstract
Splicing is a highly regulated process critical for proper pre-mRNA maturation and the maintenance of a healthy cellular environment. Splicing events are impacted by ongoing transcription, neighboring splicing events, and cis and trans regulatory factors on the respective pre-mRNA transcript. Within this complex regulatory environment, splicing kinetics have the potential to influence splicing outcomes but have historically been challenging to study in vivo. In this review, we highlight recent technological advancements that have enabled measurements of global splicing kinetics and of the variability of splicing kinetics at single introns. We demonstrate how identifying features that are correlated with splicing kinetics has increased our ability to form potential models for how splicing kinetics may be regulated in vivo.
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Affiliation(s)
- Hope E Merens
- Harvard University, Department of Genetics, Boston, MA, USA
| | - Karine Choquet
- University of Sherbrooke, Department of Biochemistry and Functional Genomics, Sherbrooke, Québec, Canada
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8
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Rojas P, Wang J, Guglielmi G, Sadurnì MM, Pavlou L, Leung GHD, Rajagopal V, Spill F, Saponaro M. Genome-wide identification of replication fork stalling/pausing sites and the interplay between RNA Pol II transcription and DNA replication progression. Genome Biol 2024; 25:126. [PMID: 38773641 PMCID: PMC11106976 DOI: 10.1186/s13059-024-03278-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Accepted: 05/14/2024] [Indexed: 05/24/2024] Open
Abstract
BACKGROUND DNA replication progression can be affected by the presence of physical barriers like the RNA polymerases, leading to replication stress and DNA damage. Nonetheless, we do not know how transcription influences overall DNA replication progression. RESULTS To characterize sites where DNA replication forks stall and pause, we establish a genome-wide approach to identify them. This approach uses multiple timepoints during S-phase to identify replication fork/stalling hotspots as replication progresses through the genome. These sites are typically associated with increased DNA damage, overlapped with fragile sites and with breakpoints of rearrangements identified in cancers but do not overlap with replication origins. Overlaying these sites with a genome-wide analysis of RNA polymerase II transcription, we find that replication fork stalling/pausing sites inside genes are directly related to transcription progression and activity. Indeed, we find that slowing down transcription elongation slows down directly replication progression through genes. This indicates that transcription and replication can coexist over the same regions. Importantly, rearrangements found in cancers overlapping transcription-replication collision sites are detected in non-transformed cells and increase following treatment with ATM and ATR inhibitors. At the same time, we find instances where transcription activity favors replication progression because it reduces histone density. CONCLUSIONS Altogether, our findings highlight how transcription and replication overlap during S-phase, with both positive and negative consequences for replication fork progression and genome stability by the coexistence of these two processes.
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Affiliation(s)
- Patricia Rojas
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Jianming Wang
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Giovanni Guglielmi
- School of Mathematics, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
- Department of Biomedical Engineering, University of Melbourne, Melbourne, VIC, 3010, Australia
| | - Martina Mustè Sadurnì
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Lucas Pavlou
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Geoffrey Ho Duen Leung
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Vijay Rajagopal
- Department of Biomedical Engineering, University of Melbourne, Melbourne, VIC, 3010, Australia
| | - Fabian Spill
- School of Mathematics, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
| | - Marco Saponaro
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, B15 2TT, UK.
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9
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Wang Y, Wang S, Meng Z, Liu XM, Mao Y. Determinant of m6A regional preference by transcriptional dynamics. Nucleic Acids Res 2024; 52:3510-3521. [PMID: 38452220 DOI: 10.1093/nar/gkae169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2023] [Revised: 02/21/2024] [Accepted: 02/27/2024] [Indexed: 03/09/2024] Open
Abstract
N6-Methyladenosine (m6A) is the most abundant chemical modification occurring on eukaryotic mRNAs, and has been reported to be involved in almost all stages of mRNA metabolism. The distribution of m6A sites is notably asymmetric along mRNAs, with a strong preference toward the 3' terminus of the transcript. How m6A regional preference is shaped remains incompletely understood. In this study, by performing m6A-seq on chromatin-associated RNAs, we found that m6A regional preference arises during transcription. Nucleosome occupancy is remarkedly increased in the region downstream of m6A sites, suggesting an intricate interplay between m6A methylation and nucleosome-mediated transcriptional dynamics. Notably, we found a remarkable slowdown of Pol-II movement around m6A sites. In addition, inhibiting Pol-II movement increases nearby m6A methylation levels. By analyzing massively parallel assays for m6A, we found that RNA secondary structures inhibit m6A methylation. Remarkably, the m6A sites associated with Pol-II pausing tend to be embedded within RNA secondary structures. These results suggest that Pol-II pausing could affect the accessibility of m6A motifs to the methyltransferase complex and subsequent m6A methylation by mediating RNA secondary structure. Overall, our study reveals a crucial role of transcriptional dynamics in the formation of m6A regional preference.
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Affiliation(s)
- Yalan Wang
- Department of Neurology of The Second Affiliated Hospital & Liangzhu Laboratory, Zhejiang University School of Medicine, Hangzhou, China
- Shanghai Key Laboratory of Metabolic Remodeling and Health, Institute of Metabolism and Integrative Biology, Institute of Reproduction and Development, Fudan University, Shanghai, China
| | - Shen Wang
- School of Life Science and Technology, China Pharmaceutical University, Nanjing, China
| | - Zhen Meng
- Department of Neurology of The Second Affiliated Hospital & Liangzhu Laboratory, Zhejiang University School of Medicine, Hangzhou, China
| | - Xiao-Min Liu
- School of Life Science and Technology, China Pharmaceutical University, Nanjing, China
| | - Yuanhui Mao
- Department of Neurology of The Second Affiliated Hospital & Liangzhu Laboratory, Zhejiang University School of Medicine, Hangzhou, China
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10
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Coté A, O'Farrell A, Dardani I, Dunagin M, Coté C, Wan Y, Bayatpour S, Drexler HL, Alexander KA, Chen F, Wassie AT, Patel R, Pham K, Boyden ES, Berger S, Phillips-Cremins J, Churchman LS, Raj A. Post-transcriptional splicing can occur in a slow-moving zone around the gene. eLife 2024; 12:RP91357. [PMID: 38577979 PMCID: PMC10997330 DOI: 10.7554/elife.91357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/06/2024] Open
Abstract
Splicing is the stepwise molecular process by which introns are removed from pre-mRNA and exons are joined together to form mature mRNA sequences. The ordering and spatial distribution of these steps remain controversial, with opposing models suggesting splicing occurs either during or after transcription. We used single-molecule RNA FISH, expansion microscopy, and live-cell imaging to reveal the spatiotemporal distribution of nascent transcripts in mammalian cells. At super-resolution levels, we found that pre-mRNA formed clouds around the transcription site. These clouds indicate the existence of a transcription-site-proximal zone through which RNA move more slowly than in the nucleoplasm. Full-length pre-mRNA undergo continuous splicing as they move through this zone following transcription, suggesting a model in which splicing can occur post-transcriptionally but still within the proximity of the transcription site, thus seeming co-transcriptional by most assays. These results may unify conflicting reports of co-transcriptional versus post-transcriptional splicing.
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Affiliation(s)
- Allison Coté
- Department of Bioengineering, University of PennsylvaniaPhiladelphiaUnited States
| | - Aoife O'Farrell
- Department of Bioengineering, University of PennsylvaniaPhiladelphiaUnited States
| | - Ian Dardani
- Department of Bioengineering, University of PennsylvaniaPhiladelphiaUnited States
| | - Margaret Dunagin
- Department of Bioengineering, University of PennsylvaniaPhiladelphiaUnited States
| | - Chris Coté
- Department of Bioengineering, University of PennsylvaniaPhiladelphiaUnited States
| | - Yihan Wan
- School of Life Sciences, Westlake UniversityHangzhouChina
| | - Sareh Bayatpour
- Department of Bioengineering, University of PennsylvaniaPhiladelphiaUnited States
| | - Heather L Drexler
- Department of Genetics, Blavatnik Institute, Harvard Medical SchoolBostonUnited States
| | - Katherine A Alexander
- Department of Cell and Developmental Biology, Penn Institute of Epigenetics, Perelman School of Medicine, University of PennsylvaniaPhiladelphiaUnited States
| | - Fei Chen
- Broad Institute of MIT and HarvardCambridgeUnited States
| | - Asmamaw T Wassie
- Department of Cell and Molecular Biology, University of PennsylvaniaPhiladelphiaUnited States
| | - Rohan Patel
- Department of Bioengineering, University of PennsylvaniaPhiladelphiaUnited States
| | - Kenneth Pham
- Department of Cell and Molecular Biology, University of PennsylvaniaPhiladelphiaUnited States
| | - Edward S Boyden
- Departments of Biological Engineering and Brain and Cognitive Sciences, Media Lab and McGovern Institute, Massachusetts Institute of TechnologyCambridgeUnited States
| | - Shelly Berger
- Department of Cell and Developmental Biology, Penn Institute of Epigenetics, Perelman School of Medicine, University of PennsylvaniaPhiladelphiaUnited States
| | | | - L Stirling Churchman
- Department of Genetics, Blavatnik Institute, Harvard Medical SchoolBostonUnited States
| | - Arjun Raj
- Department of Bioengineering, University of PennsylvaniaPhiladelphiaUnited States
- Department of Genetics, Perelman School of Medicine, University of PennsylvaniaPhiladelphiaUnited States
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11
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Silver BD, Willett CG, Maher KA, Wang D, Deal RB. Differences in transcription initiation directionality underlie distinctions between plants and animals in chromatin modification patterns at genes and cis-regulatory elements. G3 (BETHESDA, MD.) 2024; 14:jkae016. [PMID: 38253712 PMCID: PMC10917500 DOI: 10.1093/g3journal/jkae016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Revised: 11/10/2023] [Accepted: 01/11/2024] [Indexed: 01/24/2024]
Abstract
Transcriptional initiation is among the first regulated steps controlling eukaryotic gene expression. High-throughput profiling of fungal and animal genomes has revealed that RNA Polymerase II often initiates transcription in both directions at the promoter transcription start site, but generally only elongates productively into the gene body. Additionally, Pol II can initiate transcription in both directions at cis-regulatory elements such as enhancers. These bidirectional RNA Polymerase II initiation events can be observed directly with methods that capture nascent transcripts, and they are also revealed indirectly by the presence of transcription-associated histone modifications on both sides of the transcription start site or cis-regulatory elements. Previous studies have shown that nascent RNAs and transcription-associated histone modifications in the model plant Arabidopsis thaliana accumulate mainly in the gene body, suggesting that transcription does not initiate widely in the upstream direction from genes in this plant. We compared transcription-associated histone modifications and nascent transcripts at both transcription start sites and cis-regulatory elements in A. thaliana, Drosophila melanogaster, and Homo sapiens. Our results provide evidence for mostly unidirectional RNA Polymerase II initiation at both promoters and gene-proximal cis-regulatory elements of A. thaliana, whereas bidirectional transcription initiation is observed widely at promoters in both D. melanogaster and H. sapiens, as well as cis-regulatory elements in Drosophila. Furthermore, the distribution of transcription-associated histone modifications around transcription start sites in the Oryza sativa (rice) and Glycine max (soybean) genomes suggests that unidirectional transcription initiation is the norm in these genomes as well. These results suggest that there are fundamental differences in transcriptional initiation directionality between flowering plant and metazoan genomes, which are manifested as distinct patterns of chromatin modifications around RNA polymerase initiation sites.
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Affiliation(s)
- Brianna D Silver
- Department of Biology, Emory University, Atlanta, GA 30322, USA
- Graduate Program in Genetics and Molecular Biology, Emory University, Atlanta, GA 30322, USA
| | - Courtney G Willett
- Department of Biology, Emory University, Atlanta, GA 30322, USA
- Graduate Program in Genetics and Molecular Biology, Emory University, Atlanta, GA 30322, USA
| | - Kelsey A Maher
- Department of Biology, Emory University, Atlanta, GA 30322, USA
- Graduate Program in Biochemistry, Cell, and Developmental Biology, Emory University, Atlanta, GA 30322, USA
- Department of Computational Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Dongxue Wang
- Department of Biology, Emory University, Atlanta, GA 30322, USA
- School of Medicine, Emory University, Atlanta, GA 30322, USA
| | - Roger B Deal
- Department of Biology, Emory University, Atlanta, GA 30322, USA
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12
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Cornejo KG, Venegas A, Sono MH, Door M, Gutierrez-Ruiz B, Karabedian LB, Nandi SG, Dykhuizen EC, Saha RN. Activity-assembled nBAF complex mediates rapid immediate early gene transcription by regulating RNA Polymerase II productive elongation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.30.573688. [PMID: 38234780 PMCID: PMC10793463 DOI: 10.1101/2023.12.30.573688] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2024]
Abstract
Signal-dependent RNA Polymerase II (Pol2) productive elongation is an integral component of gene transcription, including those of immediate early genes (IEGs) induced by neuronal activity. However, it remains unclear how productively elongating Pol2 overcome nucleosomal barriers. Using RNAi, three degraders, and several small molecule inhibitors, we show that the mammalian SWI/SNF complex of neurons (neuronal BAF, or nBAF) is required for activity-induced transcription of neuronal IEGs, including Arc . The nBAF complex facilitates promoter-proximal Pol2 pausing, signal-dependent Pol2 recruitment (loading), and importantly, mediates productive elongation in the gene body via interaction with the elongation complex and elongation-competent Pol2. Mechanistically, Pol2 elongation is mediated by activity-induced nBAF assembly (especially, ARID1A recruitment) and its ATPase activity. Together, our data demonstrate that the nBAF complex regulates several aspects of Pol2 transcription and reveal mechanisms underlying activity-induced Pol2 elongation. These findings may offer insights into human maladies etiologically associated with mutational interdiction of BAF functions.
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13
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Liu L, Zhao Y, Siepel A. DNA-sequence and epigenomic determinants of local rates of transcription elongation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.21.572932. [PMID: 38187771 PMCID: PMC10769381 DOI: 10.1101/2023.12.21.572932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2024]
Abstract
Across all branches of life, transcription elongation is a crucial, regulated phase in gene expression. Many recent studies in eukaryotes have focused on the regulation of promoter-proximal pausing of RNA Polymerase II (Pol II), but rates of productive elongation also vary substantially throughout the gene body, both within and across genes. Here, we introduce a probabilistic model for systematically evaluating potential determinants of the local elongation rate based on nascent RNA sequencing (NRS) data. Our model is derived from a unified model for both the kinetics of Pol II movement along the DNA template and the generation of NRS read counts at steady state. It allows for a continuously variable elongation rate along the gene body, with the rate at each nucleotide defined by a generalized linear relationship with nearby genomic and epigenomic features. High-dimensional feature vectors are accommodated through a sparse-regression extension. We show with simulations that the model allows accurate detection of associated features and accurate prediction of local elongation rates. In an analysis of public PRO-seq and epigenomic data, we identify several features that are strongly associated with reductions in the local elongation rate, including DNA methylation, splice sites, RNA stem-loops, CTCF binding sites, and several histone marks, including H3K36me3 and H4K20me1. By contrast, low-complexity sequences and H3K79me2 marks are associated with increases in elongation rate. In an analysis of DNA k -mers, we find that cytosine nucleotides are strongly associated with reductions in local elongation rate, particularly when preceded by guanines and followed by adenines or thymines. Increases in elongation rate are associated with thymines and A+T-rich k -mers. These associations are generally shared across cell types, and by considering them our model is effective at predicting features of held-out PRO-seq data. Overall, our analysis is the first to permit genome-wide predictions of relative nucleotide-specific elongation rates based on complex sets of genomic and epigenomic covariates. We have made predictions available for the K562, CD14+, MCF-7, and HeLa-S3 cell types in a UCSC Genome Browser track.
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Affiliation(s)
- Lingjie Liu
- Simons Center for Quantitative Biology, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY
- Graduate Program in Genetics, Stony Brook University, Stony Brook, NY
| | - Yixin Zhao
- Simons Center for Quantitative Biology, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY
| | - Adam Siepel
- Simons Center for Quantitative Biology, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY
- Graduate Program in Genetics, Stony Brook University, Stony Brook, NY
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14
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Liu M, Zhu J, Huang H, Chen Y, Dong Z. Comparative analysis of nascent RNA sequencing methods and their applications in studies of cotranscriptional splicing dynamics. THE PLANT CELL 2023; 35:4304-4324. [PMID: 37708036 PMCID: PMC10689179 DOI: 10.1093/plcell/koad237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 08/13/2023] [Accepted: 08/24/2023] [Indexed: 09/16/2023]
Abstract
High-throughput detection of nascent RNA is critical for studies of transcription and much more challenging than that of mRNA. Recently, several massively parallel nascent RNA sequencing methods were established in eukaryotic cells. Here, we systematically compared 3 classes of methods on the same pure or crude nuclei preparations: GRO-seq for sequence nuclear run-on RNAs, pNET-seq for sequence RNA polymerase II-associated RNAs, and CB RNA-seq for sequence chromatin-bound (CB) RNAs in Arabidopsis (Arabidopsis thaliana). To improve the resolution of CB RNAs, 3'CB RNA-seq was established to sequence the 3' ends of CB RNAs. In addition, we modified pNET-seq to establish the Chromatin Native Elongation Transcript sequencing (ChrNET) method using chromatin as the starting material for RNA immunoprecipitation. Reproducibility, sensitivity and accuracy in detecting nascent transcripts, experimental procedures, and costs were analyzed, which revealed the strengths and weaknesses of each method. We found that pNET and GRO methods best detected active RNA polymerase II. CB RNA-seq is a simple and cost-effective alternative for nascent RNA studies, due to its high correlation with pNET-seq and GRO-seq. Compared with pNET, ChrNET has higher specificity for nascent RNA capture and lower sequencing cost. 3'CB is sensitive to transcription-coupled splicing. Using these methods, we identified 1,404 unknown transcripts, 4,482 unannotated splicing events, and 60 potential recursive splicing events. This comprehensive comparison of different nascent/chromatin RNA sequencing methods highlights the strengths of each method and serves as a guide for researchers aiming to select a method that best meets their study goals.
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Affiliation(s)
- Min Liu
- Guangdong Provincial Key Laboratory of Plant Adaptation and Molecular Design, Guangzhou Key Laboratory of Crop Gene Editing, Innovative Center of Molecular Genetics and Evolution, School of Life Sciences, Guangzhou University, Guangzhou 510006, China
| | - Jiafu Zhu
- Guangdong Provincial Key Laboratory of Plant Adaptation and Molecular Design, Guangzhou Key Laboratory of Crop Gene Editing, Innovative Center of Molecular Genetics and Evolution, School of Life Sciences, Guangzhou University, Guangzhou 510006, China
| | - Huijuan Huang
- Guangdong Provincial Key Laboratory of Plant Adaptation and Molecular Design, Guangzhou Key Laboratory of Crop Gene Editing, Innovative Center of Molecular Genetics and Evolution, School of Life Sciences, Guangzhou University, Guangzhou 510006, China
| | - Yan Chen
- Guangdong Provincial Key Laboratory of Plant Adaptation and Molecular Design, Guangzhou Key Laboratory of Crop Gene Editing, Innovative Center of Molecular Genetics and Evolution, School of Life Sciences, Guangzhou University, Guangzhou 510006, China
| | - Zhicheng Dong
- Guangdong Provincial Key Laboratory of Plant Adaptation and Molecular Design, Guangzhou Key Laboratory of Crop Gene Editing, Innovative Center of Molecular Genetics and Evolution, School of Life Sciences, Guangzhou University, Guangzhou 510006, China
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15
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Silver BD, Willett CG, Maher KA, Wang D, Deal RB. Differences in transcription initiation directionality underlie distinctions between plants and animals in chromatin modification patterns at genes and cis-regulatory elements. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.03.565513. [PMID: 37961418 PMCID: PMC10635121 DOI: 10.1101/2023.11.03.565513] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
Transcriptional initiation is among the first regulated steps controlling eukaryotic gene expression. High-throughput profiling of fungal and animal genomes has revealed that RNA Polymerase II (Pol II) often initiates transcription in both directions at the promoter transcription start site (TSS), but generally only elongates productively into the gene body. Additionally, Pol II can initiate transcription in both directions at cis-regulatory elements (CREs) such as enhancers. These bidirectional Pol II initiation events can be observed directly with methods that capture nascent transcripts, and they are also revealed indirectly by the presence of transcription-associated histone modifications on both sides of the TSS or CRE. Previous studies have shown that nascent RNAs and transcription-associated histone modifications in the model plant Arabidopsis thaliana accumulate mainly in the gene body, suggesting that transcription does not initiate widely in the upstream direction from genes in this plant. We compared transcription-associated histone modifications and nascent transcripts at both TSSs and CREs in Arabidopsis thaliana, Drosophila melanogaster, and Homo sapiens. Our results provide evidence for mostly unidirectional Pol II initiation at both promoters and gene-proximal CREs of Arabidopsis thaliana, whereas bidirectional transcription initiation is observed widely at promoters in both Drosophila melanogaster and Homo sapiens, as well as CREs in Drosophila. Furthermore, the distribution of transcription-associated histone modifications around TSSs in the Oryza sativa (rice) and Glycine max (soybean) genomes suggests that unidirectional transcription initiation is the norm in these genomes as well. These results suggest that there are fundamental differences in transcriptional initiation directionality between flowering plant and metazoan genomes, which are manifested as distinct patterns of chromatin modifications around RNA polymerase initiation sites.
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Affiliation(s)
- Brianna D. Silver
- Department of Biology, Emory University, Atlanta, GA 30322 USA
- Graduate Program in Genetics and Molecular Biology, Emory University, Atlanta, GA 30322 USA
| | - Courtney G. Willett
- Department of Biology, Emory University, Atlanta, GA 30322 USA
- Graduate Program in Genetics and Molecular Biology, Emory University, Atlanta, GA 30322 USA
| | - Kelsey A. Maher
- Department of Biology, Emory University, Atlanta, GA 30322 USA
- Graduate Program in Biochemistry, Cell, and Developmental Biology, Emory University, Atlanta, GA 30322 USA
| | - Dongxue Wang
- Department of Biology, Emory University, Atlanta, GA 30322 USA
| | - Roger B. Deal
- Department of Biology, Emory University, Atlanta, GA 30322 USA
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16
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Lee SA, Kristjánsdóttir K, Kwak H. eRNA co-expression network uncovers TF dependency and convergent cooperativity. Sci Rep 2023; 13:19085. [PMID: 37925545 PMCID: PMC10625640 DOI: 10.1038/s41598-023-46415-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Accepted: 10/31/2023] [Indexed: 11/06/2023] Open
Abstract
Enhancer RNAs (eRNAs) are non-coding RNAs produced by transcriptional enhancers that are highly correlated with their activity. Using a capped nascent RNA sequencing (PRO-cap) dataset in human lymphoblastoid cell lines across 67 individuals, we identified inter-individual variation in the expression of over 80 thousand transcribed transcriptional regulatory elements (tTREs), in both enhancers and promoters. Co-expression analysis of eRNAs from tTREs across individuals revealed how enhancers are associated with each other and with promoters. Mid- to long-range co-expression showed a distance-dependent decay that was modified by TF occupancy. In particular, we found a class of "bivalent" TFs, including Cohesin, that both facilitate and isolate the interaction between enhancers and/or promoters, depending on their topology. At short distances, we observed strand-specific correlations between nearby eRNAs in both convergent and divergent orientations. Our results support a cooperative model of convergent eRNAs, consistent with eRNAs facilitating adjacent enhancers rather than interfering with each other. Therefore, our approach to infer functional interactions from co-expression analyses provided novel insights into the principles of enhancer interactions as a function of distance, orientation, and binding landscapes of TFs.
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Affiliation(s)
- Seungha Alisa Lee
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, 14850, USA
| | - Katla Kristjánsdóttir
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, 14850, USA
| | - Hojoong Kwak
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, 14850, USA.
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17
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Arnold M, Stengel KR. Emerging insights into enhancer biology and function. Transcription 2023; 14:68-87. [PMID: 37312570 PMCID: PMC10353330 DOI: 10.1080/21541264.2023.2222032] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 05/30/2023] [Accepted: 06/01/2023] [Indexed: 06/15/2023] Open
Abstract
Cell type-specific gene expression is coordinated by DNA-encoded enhancers and the transcription factors (TFs) that bind to them in a sequence-specific manner. As such, these enhancers and TFs are critical mediators of normal development and altered enhancer or TF function is associated with the development of diseases such as cancer. While initially defined by their ability to activate gene transcription in reporter assays, putative enhancer elements are now frequently defined by their unique chromatin features including DNase hypersensitivity and transposase accessibility, bidirectional enhancer RNA (eRNA) transcription, CpG hypomethylation, high H3K27ac and H3K4me1, sequence-specific transcription factor binding, and co-factor recruitment. Identification of these chromatin features through sequencing-based assays has revolutionized our ability to identify enhancer elements on a genome-wide scale, and genome-wide functional assays are now capitalizing on this information to greatly expand our understanding of how enhancers function to provide spatiotemporal coordination of gene expression programs. Here, we highlight recent technological advances that are providing new insights into the molecular mechanisms by which these critical cis-regulatory elements function in gene control. We pay particular attention to advances in our understanding of enhancer transcription, enhancer-promoter syntax, 3D organization and biomolecular condensates, transcription factor and co-factor dependencies, and the development of genome-wide functional enhancer screens.
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Affiliation(s)
- Mirjam Arnold
- Department of Cell Biology, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Kristy R. Stengel
- Department of Cell Biology, Albert Einstein College of Medicine, Bronx, NY, USA
- Montefiore Einstein Cancer Center, Albert Einstein College of Medicine-Montefiore Health System, Bronx, NY, USA
- Ruth L. and David S. Gottesman Institute for Stem Cell and Regenerative Medicine Research, Albert Einstein College of Medicine, Bronx, NY, USA
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18
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Martell DJ, Merens HE, Caulier A, Fiorini C, Ulirsch JC, Ietswaart R, Choquet K, Graziadei G, Brancaleoni V, Cappellini MD, Scott C, Roberts N, Proven M, Roy NBA, Babbs C, Higgs DR, Sankaran VG, Churchman LS. RNA polymerase II pausing temporally coordinates cell cycle progression and erythroid differentiation. Dev Cell 2023; 58:2112-2127.e4. [PMID: 37586368 PMCID: PMC10615711 DOI: 10.1016/j.devcel.2023.07.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 05/23/2023] [Accepted: 07/25/2023] [Indexed: 08/18/2023]
Abstract
Controlled release of promoter-proximal paused RNA polymerase II (RNA Pol II) is crucial for gene regulation. However, studying RNA Pol II pausing is challenging, as pause-release factors are almost all essential. In this study, we identified heterozygous loss-of-function mutations in SUPT5H, which encodes SPT5, in individuals with β-thalassemia. During erythropoiesis in healthy human cells, cell cycle genes were highly paused as cells transition from progenitors to precursors. When the pathogenic mutations were recapitulated by SUPT5H editing, RNA Pol II pause release was globally disrupted, and as cells began transitioning from progenitors to precursors, differentiation was delayed, accompanied by a transient lag in erythroid-specific gene expression and cell cycle kinetics. Despite this delay, cells terminally differentiate, and cell cycle phase distributions normalize. Therefore, hindering pause release perturbs proliferation and differentiation dynamics at a key transition during erythropoiesis, identifying a role for RNA Pol II pausing in temporally coordinating the cell cycle and erythroid differentiation.
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Affiliation(s)
- Danya J Martell
- Department of Genetics, Harvard University, Boston, MA, USA; Division of Hematology/Oncology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA; Department of Pediatric Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA; Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Hope E Merens
- Department of Genetics, Harvard University, Boston, MA, USA
| | - Alexis Caulier
- Division of Hematology/Oncology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA; Department of Pediatric Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA; Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Claudia Fiorini
- Division of Hematology/Oncology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA; Department of Pediatric Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA; Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Jacob C Ulirsch
- Division of Hematology/Oncology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA; Department of Pediatric Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA; Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | | | - Karine Choquet
- Department of Genetics, Harvard University, Boston, MA, USA
| | - Giovanna Graziadei
- Department of Clinical Sciences and Community, University of Milan, IRCCS Ca'Granda Foundation Maggiore Policlinico Hospital, Milan, Italy
| | - Valentina Brancaleoni
- Department of Clinical Sciences and Community, University of Milan, IRCCS Ca'Granda Foundation Maggiore Policlinico Hospital, Milan, Italy
| | - Maria Domenica Cappellini
- Department of Clinical Sciences and Community, University of Milan, IRCCS Ca'Granda Foundation Maggiore Policlinico Hospital, Milan, Italy
| | - Caroline Scott
- MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Nigel Roberts
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Melanie Proven
- Oxford Genetics Laboratories, Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| | - Noémi B A Roy
- MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK; NIHR Oxford Biomedical Research Centre and BRC/NHS Translational Molecular Diagnostics Centre, John Radcliffe Hospital, Oxford, UK; Department of Haematology, Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| | - Christian Babbs
- MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Douglas R Higgs
- MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Vijay G Sankaran
- Division of Hematology/Oncology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA; Department of Pediatric Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA; Broad Institute of MIT and Harvard, Cambridge, MA, USA.
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19
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Karlebach G, Steinhaus R, Danis D, Devoucoux M, Anczuków O, Sheynkman G, Seelow D, Robinson PN. Alternative splicing is coupled to gene expression in a subset of variably expressed genes. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.13.544742. [PMID: 37398049 PMCID: PMC10312658 DOI: 10.1101/2023.06.13.544742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/04/2023]
Abstract
Numerous factors regulate alternative splicing of human genes at a co-transcriptional level. However, how alternative splicing depends on the regulation of gene expression is poorly understood. We leveraged data from the Genotype-Tissue Expression (GTEx) project to show a significant association of gene expression and splicing for 6874 (4.9%) of 141,043 exons in 1106 (13.3%) of 8314 genes with substantially variable expression in ten GTEx tissues. About half of these exons demonstrate higher inclusion with higher gene expression, and half demonstrate higher exclusion, with the observed direction of coupling being highly consistent across different tissues and in external datasets. The exons differ with respect to sequence characteristics, enriched sequence motifs, RNA polymerase II binding, and inferred transcription rate of downstream introns. The exons were enriched for hundreds of isoform-specific Gene Ontology annotations, suggesting that the coupling of expression and alternative splicing described here may provide an important gene regulatory mechanism that might be used in a variety of biological contexts. In particular, higher inclusion exons could play an important role during cell division.
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Affiliation(s)
- Guy Karlebach
- The Jackson Laboratory for Genomic Medicine, Farmington, CT 06032, USA
| | - Robin Steinhaus
- Exploratory Diagnostic Sciences, Berlin Institute of Health, 10117 Berlin, Germany
- Institute of Medical Genetics and Human Genetics, Charité - Universitätsmedizin Berlin, corporate member of Freie Universitat Berlin and Humboldt-Universität zu Berlin, 13353 10117 Berlin, Germany
| | - Daniel Danis
- The Jackson Laboratory for Genomic Medicine, Farmington, CT 06032, USA
| | - Maeva Devoucoux
- The Jackson Laboratory for Genomic Medicine, Farmington, CT 06032, USA
| | - Olga Anczuków
- The Jackson Laboratory for Genomic Medicine, Farmington, CT 06032, USA
- Department of Genetics and Genome Sciences, UConn Health, Farmington, CT 06032, USA
- Institute for Systems Genomics, University of Connecticut, Farmington, CT 06032, USA
| | - Gloria Sheynkman
- Department of Molecular Physiology and Biological Physics, University of Virginia School of Medicine, Charlottesville, VA 22903, USA
| | - Dominik Seelow
- Exploratory Diagnostic Sciences, Berlin Institute of Health, 10117 Berlin, Germany
- Institute of Medical Genetics and Human Genetics, Charité - Universitätsmedizin Berlin, corporate member of Freie Universitat Berlin and Humboldt-Universität zu Berlin, 13353 10117 Berlin, Germany
| | - Peter N Robinson
- The Jackson Laboratory for Genomic Medicine, Farmington, CT 06032, USA
- Department of Molecular Physiology and Biological Physics, University of Virginia School of Medicine, Charlottesville, VA 22903, USA
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20
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Cortázar MA, Fong N, Bentley DL. Genome-wide Mapping of 5'-monophosphorylated Ends of Mammalian Nascent RNA Transcripts. Bio Protoc 2023; 13:e4828. [PMID: 37753464 PMCID: PMC10518774 DOI: 10.21769/bioprotoc.4828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 05/08/2023] [Accepted: 05/15/2023] [Indexed: 09/28/2023] Open
Abstract
In eukaryotic cells, RNA biogenesis generally requires processing of the nascent transcript as it is being synthesized by RNA polymerase. These processing events include endonucleolytic cleavage, exonucleolytic trimming, and splicing of the growing nascent transcript. Endonucleolytic cleavage events that generate an exposed 5'-monophosphorylated (5'-PO4) end on the growing nascent transcript occur in the maturation of rRNAs, tRNAs, and mRNAs. These 5'-PO4 ends can be a target of further processing or be subjected to 5'-3' exonucleolytic digestion that may result in termination of transcription. Here, we describe how to identify 5'-PO4 ends of intermediates in nascent RNA metabolism. We capture these species via metabolic labeling with bromouridine followed by immunoprecipitation and specific ligation of 5'-PO4 RNA ends with the 3'-hydroxyl group of a 5' adaptor (5'-PO4 Bru-Seq) using RNA ligase I. These ligation events are localized at single nucleotide resolution via highthroughput sequencing, which identifies the position of 5'-PO4 groups precisely. This protocol successfully detects the 5'monophosphorylated ends of RNA processing intermediates during production of mature ribosomal, transfer, and micro RNAs. When combined with inhibition of the nuclear 5'-3' exonuclease Xrn2, 5'-PO4 Bru-Seq maps the 5' splice sites of debranched introns and mRNA and tRNA 3' end processing sites cleaved by CPSF73 and RNaseZ, respectively. Key features • Metabolic labeling for brief periods with bromouridine focuses the analysis of 5'-PO4 RNA ends on the population of nascent transcripts that are actively transcribed. • Detects 5'-PO4 RNA ends on nascent transcripts produced by all RNA polymerases. • Detects 5'-PO4 RNA ends at single nucleotide resolution.
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Affiliation(s)
- Michael A. Cortázar
- Department of Biochemistry and Molecular Genetics, RNA Bioscience Initiative, University of Colorado School of Medicine, Aurora, CO, USA
| | - Nova Fong
- Department of Biochemistry and Molecular Genetics, RNA Bioscience Initiative, University of Colorado School of Medicine, Aurora, CO, USA
| | - David L. Bentley
- Department of Biochemistry and Molecular Genetics, RNA Bioscience Initiative, University of Colorado School of Medicine, Aurora, CO, USA
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21
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Bressin A, Jasnovidova O, Arnold M, Altendorfer E, Trajkovski F, Kratz TA, Handzlik JE, Hnisz D, Mayer A. High-sensitive nascent transcript sequencing reveals BRD4-specific control of widespread enhancer and target gene transcription. Nat Commun 2023; 14:4971. [PMID: 37591883 PMCID: PMC10435483 DOI: 10.1038/s41467-023-40633-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Accepted: 08/02/2023] [Indexed: 08/19/2023] Open
Abstract
Gene transcription by RNA polymerase II (Pol II) is under control of promoters and distal regulatory elements known as enhancers. Enhancers are themselves transcribed by Pol II correlating with their activity. How enhancer transcription is regulated and coordinated with transcription at target genes has remained unclear. Here, we developed a high-sensitive native elongating transcript sequencing approach, called HiS-NET-seq, to provide an extended high-resolution view on transcription, especially at lowly transcribed regions such as enhancers. HiS-NET-seq uncovers new transcribed enhancers in human cells. A multi-omics analysis shows that genome-wide enhancer transcription depends on the BET family protein BRD4. Specifically, BRD4 co-localizes to enhancer and promoter-proximal gene regions, and is required for elongation activation at enhancers and their genes. BRD4 keeps a set of enhancers and genes in proximity through long-range contacts. From these studies BRD4 emerges as a general regulator of enhancer transcription that may link transcription at enhancers and genes.
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Affiliation(s)
- Annkatrin Bressin
- Otto-Warburg-Laboratory, Max Planck Institute for Molecular Genetics, 14195, Berlin, Germany
- Department of Mathematics and Computer Science, Freie Universität Berlin, 14195, Berlin, Germany
| | - Olga Jasnovidova
- Otto-Warburg-Laboratory, Max Planck Institute for Molecular Genetics, 14195, Berlin, Germany
| | - Mirjam Arnold
- Otto-Warburg-Laboratory, Max Planck Institute for Molecular Genetics, 14195, Berlin, Germany
- Department of Biology, Chemistry, and Pharmacy, Freie Universität Berlin, 14195, Berlin, Germany
| | - Elisabeth Altendorfer
- Otto-Warburg-Laboratory, Max Planck Institute for Molecular Genetics, 14195, Berlin, Germany
| | - Filip Trajkovski
- Otto-Warburg-Laboratory, Max Planck Institute for Molecular Genetics, 14195, Berlin, Germany
- Department of Biology, Chemistry, and Pharmacy, Freie Universität Berlin, 14195, Berlin, Germany
| | - Thomas A Kratz
- Otto-Warburg-Laboratory, Max Planck Institute for Molecular Genetics, 14195, Berlin, Germany
- Department of Biology, Chemistry, and Pharmacy, Freie Universität Berlin, 14195, Berlin, Germany
| | - Joanna E Handzlik
- Otto-Warburg-Laboratory, Max Planck Institute for Molecular Genetics, 14195, Berlin, Germany
| | - Denes Hnisz
- Department of Genome Regulation, Max Planck Institute for Molecular Genetics, 14195, Berlin, Germany
| | - Andreas Mayer
- Otto-Warburg-Laboratory, Max Planck Institute for Molecular Genetics, 14195, Berlin, Germany.
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22
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Fan K, Pfister E, Weng Z. Toward a comprehensive catalog of regulatory elements. Hum Genet 2023; 142:1091-1111. [PMID: 36935423 DOI: 10.1007/s00439-023-02519-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2022] [Accepted: 01/03/2023] [Indexed: 03/21/2023]
Abstract
Regulatory elements are the genomic regions that interact with transcription factors to control cell-type-specific gene expression in different cellular environments. A precise and complete catalog of functional elements encoded by the human genome is key to understanding mammalian gene regulation. Here, we review the current state of regulatory element annotation. We first provide an overview of assays for characterizing functional elements, including genome, epigenome, transcriptome, three-dimensional chromatin interaction, and functional validation assays. We then discuss computational methods for defining regulatory elements, including peak-calling and other statistical modeling methods. Finally, we introduce several high-quality lists of regulatory element annotations and suggest potential future directions.
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Affiliation(s)
- Kaili Fan
- Program in Bioinformatics and Integrative Biology, University of Massachusetts Chan Medical School, 368 Plantation Street, ASC5-1069, Worcester, MA, 01605, USA
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA, 02138, USA
| | - Edith Pfister
- Program in Bioinformatics and Integrative Biology, University of Massachusetts Chan Medical School, 368 Plantation Street, ASC5-1069, Worcester, MA, 01605, USA
| | - Zhiping Weng
- Program in Bioinformatics and Integrative Biology, University of Massachusetts Chan Medical School, 368 Plantation Street, ASC5-1069, Worcester, MA, 01605, USA.
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23
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Conn VM, Gabryelska M, Toubia J, Kirk K, Gantley L, Powell JA, Cildir G, Marri S, Liu R, Stringer BW, Townley S, Webb ST, Lin H, Samaraweera SE, Bailey S, Moore AS, Maybury M, Liu D, Colella AD, Chataway T, Wallington-Gates CT, Walters L, Sibbons J, Selth LA, Tergaonkar V, D'Andrea RJ, Pitson SM, Goodall GJ, Conn SJ. Circular RNAs drive oncogenic chromosomal translocations within the MLL recombinome in leukemia. Cancer Cell 2023; 41:1309-1326.e10. [PMID: 37295428 DOI: 10.1016/j.ccell.2023.05.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 03/03/2023] [Accepted: 05/03/2023] [Indexed: 06/12/2023]
Abstract
The first step of oncogenesis is the acquisition of a repertoire of genetic mutations to initiate and sustain the malignancy. An important example of this initiation phase in acute leukemias is the formation of a potent oncogene by chromosomal translocations between the mixed lineage leukemia (MLL) gene and one of 100 translocation partners, known as the MLL recombinome. Here, we show that circular RNAs (circRNAs)-a family of covalently closed, alternatively spliced RNA molecules-are enriched within the MLL recombinome and can bind DNA, forming circRNA:DNA hybrids (circR loops) at their cognate loci. These circR loops promote transcriptional pausing, proteasome inhibition, chromatin re-organization, and DNA breakage. Importantly, overexpressing circRNAs in mouse leukemia xenograft models results in co-localization of genomic loci, de novo generation of clinically relevant chromosomal translocations mimicking the MLL recombinome, and hastening of disease onset. Our findings provide fundamental insight into the acquisition of chromosomal translocations by endogenous RNA carcinogens in leukemia.
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Affiliation(s)
- Vanessa M Conn
- Flinders Health and Medical Research Institute, College of Medicine & Public Health, Flinders University, Bedford Park, SA 5042, Australia; Centre for Cancer Biology, SA Pathology & University of South Australia, Adelaide, SA 5000, Australia
| | - Marta Gabryelska
- Flinders Health and Medical Research Institute, College of Medicine & Public Health, Flinders University, Bedford Park, SA 5042, Australia
| | - John Toubia
- Centre for Cancer Biology, SA Pathology & University of South Australia, Adelaide, SA 5000, Australia; ACRF Cancer Genomics Facility, SA Pathology, Adelaide, SA 5000, Australia
| | - Kirsty Kirk
- Flinders Health and Medical Research Institute, College of Medicine & Public Health, Flinders University, Bedford Park, SA 5042, Australia
| | - Laura Gantley
- Flinders Health and Medical Research Institute, College of Medicine & Public Health, Flinders University, Bedford Park, SA 5042, Australia
| | - Jason A Powell
- Centre for Cancer Biology, SA Pathology & University of South Australia, Adelaide, SA 5000, Australia; Adelaide Medical School, Faculty of Health and Medical Sciences, the University of Adelaide, Adelaide, SA 5000, Australia
| | - Gökhan Cildir
- Centre for Cancer Biology, SA Pathology & University of South Australia, Adelaide, SA 5000, Australia
| | - Shashikanth Marri
- Flinders Health and Medical Research Institute, College of Medicine & Public Health, Flinders University, Bedford Park, SA 5042, Australia
| | - Ryan Liu
- Flinders Health and Medical Research Institute, College of Medicine & Public Health, Flinders University, Bedford Park, SA 5042, Australia
| | - Brett W Stringer
- Flinders Health and Medical Research Institute, College of Medicine & Public Health, Flinders University, Bedford Park, SA 5042, Australia
| | - Scott Townley
- Flinders Health and Medical Research Institute, College of Medicine & Public Health, Flinders University, Bedford Park, SA 5042, Australia
| | - Stuart T Webb
- Flinders Health and Medical Research Institute, College of Medicine & Public Health, Flinders University, Bedford Park, SA 5042, Australia
| | - He Lin
- Flinders Health and Medical Research Institute, College of Medicine & Public Health, Flinders University, Bedford Park, SA 5042, Australia
| | - Saumya E Samaraweera
- Centre for Cancer Biology, SA Pathology & University of South Australia, Adelaide, SA 5000, Australia
| | - Sheree Bailey
- Health and Biomedical Innovation, Clinical and Health Sciences, University of South Australia, Adelaide, SA 5000, Australia
| | - Andrew S Moore
- Child Health Research Centre, the University of Queensland, Brisbane, QLD 4101, Australia; Oncology Service, Children's Health Queensland Hospital and Health Service, Brisbane, QLD 4101, Australia
| | - Mellissa Maybury
- Child Health Research Centre, the University of Queensland, Brisbane, QLD 4101, Australia
| | - Dawei Liu
- Centre for Cancer Biology, SA Pathology & University of South Australia, Adelaide, SA 5000, Australia
| | - Alex D Colella
- Flinders Health and Medical Research Institute, College of Medicine & Public Health, Flinders University, Bedford Park, SA 5042, Australia; Flinders Omics Facility, College of Medicine & Public Health, Flinders University, Bedford Park, SA 5042, Australia
| | - Timothy Chataway
- Flinders Health and Medical Research Institute, College of Medicine & Public Health, Flinders University, Bedford Park, SA 5042, Australia; Flinders Omics Facility, College of Medicine & Public Health, Flinders University, Bedford Park, SA 5042, Australia
| | - Craig T Wallington-Gates
- Flinders Health and Medical Research Institute, College of Medicine & Public Health, Flinders University, Bedford Park, SA 5042, Australia; Centre for Cancer Biology, SA Pathology & University of South Australia, Adelaide, SA 5000, Australia; Adelaide Medical School, Faculty of Health and Medical Sciences, the University of Adelaide, Adelaide, SA 5000, Australia; Flinders Medical Centre, Bedford Park, SA 5042, Australia
| | - Lucie Walters
- Adelaide Rural Clinical School, Faculty of Health and Medical Sciences, the University of Adelaide, Adelaide, SA 5000, Australia
| | - Jane Sibbons
- Adelaide Microscopy, Division of Research and Innovation, University of Adelaide, Adelaide, SA 5000, Australia
| | - Luke A Selth
- Flinders Health and Medical Research Institute, College of Medicine & Public Health, Flinders University, Bedford Park, SA 5042, Australia; Freemasons Centre for Male Health and Wellbeing, Flinders University, Bedford Park, SA 5042, Australia
| | - Vinay Tergaonkar
- Laboratory of NFκB Signalling, Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology and Research (A(∗)STAR), 61 Biopolis Drive, Proteos, Singapore 138673, Republic of Singapore
| | - Richard J D'Andrea
- Centre for Cancer Biology, SA Pathology & University of South Australia, Adelaide, SA 5000, Australia
| | - Stuart M Pitson
- Centre for Cancer Biology, SA Pathology & University of South Australia, Adelaide, SA 5000, Australia; Adelaide Medical School, Faculty of Health and Medical Sciences, the University of Adelaide, Adelaide, SA 5000, Australia
| | - Gregory J Goodall
- Centre for Cancer Biology, SA Pathology & University of South Australia, Adelaide, SA 5000, Australia; Adelaide Medical School, Faculty of Health and Medical Sciences, the University of Adelaide, Adelaide, SA 5000, Australia
| | - Simon J Conn
- Flinders Health and Medical Research Institute, College of Medicine & Public Health, Flinders University, Bedford Park, SA 5042, Australia; Centre for Cancer Biology, SA Pathology & University of South Australia, Adelaide, SA 5000, Australia.
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24
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Bhowmick R, Mehta KPM, Lerdrup M, Cortez D. Integrator facilitates RNAPII removal to prevent transcription-replication collisions and genome instability. Mol Cell 2023; 83:2357-2366.e8. [PMID: 37295432 PMCID: PMC10330747 DOI: 10.1016/j.molcel.2023.05.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Revised: 04/17/2023] [Accepted: 05/10/2023] [Indexed: 06/12/2023]
Abstract
DNA replication preferentially initiates close to active transcription start sites (TSSs) in the human genome. Transcription proceeds discontinuously with an accumulation of RNA polymerase II (RNAPII) in a paused state near the TSS. Consequently, replication forks inevitably encounter paused RNAPII soon after replication initiates. Hence, dedicated machinery may be needed to remove RNAPII and facilitate unperturbed fork progression. In this study, we discovered that Integrator, a transcription termination machinery involved in the processing of RNAPII transcripts, interacts with the replicative helicase at active forks and promotes the removal of RNAPII from the path of the replication fork. Integrator-deficient cells have impaired replication fork progression and accumulate hallmarks of genome instability including chromosome breaks and micronuclei. The Integrator complex resolves co-directional transcription-replication conflicts to facilitate faithful DNA replication.
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Affiliation(s)
- Rahul Bhowmick
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37237, USA.
| | - Kavi P M Mehta
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37237, USA
| | - Mads Lerdrup
- Center for Chromosome Stability, Center for Healthy Aging, Department of Cellular and Molecular Medicine, University of Copenhagen, 2200 Copenhagen, Denmark
| | - David Cortez
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37237, USA.
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25
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Vilar JMG, Saiz L. Multi-landmark alignment of genomic signals reveals conserved expression patterns across transcription start sites. Sci Rep 2023; 13:10835. [PMID: 37407625 DOI: 10.1038/s41598-023-37140-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Accepted: 06/16/2023] [Indexed: 07/07/2023] Open
Abstract
The prevalent one-dimensional alignment of genomic signals to a reference landmark is a cornerstone of current methods to study transcription and its DNA-dependent processes but it is prone to mask potential relations among multiple DNA elements. We developed a systematic approach to align genomic signals to multiple locations simultaneously by expanding the dimensionality of the genomic-coordinate space. We analyzed transcription in human and uncovered a complex dependence on the relative position of neighboring transcription start sites (TSSs) that is consistently conserved among cell types. The dependence ranges from enhancement to suppression of transcription depending on the relative distances to the TSSs, their intragenic position, and the transcriptional activity of the gene. Our results reveal a conserved hierarchy of alternative TSS usage within a previously unrecognized level of genomic organization and provide a general methodology to analyze complex functional relationships among multiple types of DNA elements.
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Affiliation(s)
- Jose M G Vilar
- Biofisika Institute (CSIC, UPV/EHU), University of the Basque Country (UPV/EHU), P.O. Box 644, 48080, Bilbao, Spain.
- IKERBASQUE, Basque Foundation for Science, 48011, Bilbao, Spain.
| | - Leonor Saiz
- Department of Biomedical Engineering, University of California, 451 E. Health Sciences Drive, Davis, CA, 95616, USA.
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26
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Chauvier A, Porta JC, Deb I, Ellinger E, Meze K, Frank AT, Ohi MD, Walter NG. Structural basis for control of bacterial RNA polymerase pausing by a riboswitch and its ligand. Nat Struct Mol Biol 2023; 30:902-913. [PMID: 37264140 PMCID: PMC10523900 DOI: 10.1038/s41594-023-01002-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Accepted: 04/20/2023] [Indexed: 06/03/2023]
Abstract
Folding of nascent transcripts can be modulated by the RNA polymerase (RNAP) that carries out their transcription, and vice versa. A pause of RNAP during transcription of a preQ1 riboswitch (termed que-PEC) is stabilized by a previously characterized template consensus sequence and the ligand-free conformation of the nascent RNA. Ligand binding to the riboswitch induces RNAP pause release and downstream transcription termination; however, the mechanism by which riboswitch folding modulates pausing is unclear. Here, we report single-particle cryo-electron microscopy reconstructions of que-PEC in ligand-free and ligand-bound states. In the absence of preQ1, the RNA transcript is in an unexpected hyper-translocated state, preventing downstream nucleotide incorporation. Strikingly, on ligand binding, the riboswitch rotates around its helical axis, expanding the surrounding RNAP exit channel and repositioning the transcript for elongation. Our study reveals the tight coupling by which nascent RNA structures and their ligands can functionally regulate the macromolecular transcription machinery.
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Affiliation(s)
- Adrien Chauvier
- Single Molecule Analysis Group and Center for RNA Biomedicine, Department of Chemistry, University of Michigan, Ann Arbor, MI, USA
| | - Jason C Porta
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA
| | - Indrajit Deb
- Biophysics Program, University of Michigan, Ann Arbor, MI, USA
- Drug Discovery Unit, School of Life Sciences, University of Dundee, Dundee, UK
| | - Emily Ellinger
- Single Molecule Analysis Group and Center for RNA Biomedicine, Department of Chemistry, University of Michigan, Ann Arbor, MI, USA
| | - Katarina Meze
- Single Molecule Analysis Group and Center for RNA Biomedicine, Department of Chemistry, University of Michigan, Ann Arbor, MI, USA
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA
| | - Aaron T Frank
- Biophysics Program, University of Michigan, Ann Arbor, MI, USA
- Arrakis Therapeutics, Waltham, MA, USA
| | - Melanie D Ohi
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA.
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI, USA.
| | - Nils G Walter
- Single Molecule Analysis Group and Center for RNA Biomedicine, Department of Chemistry, University of Michigan, Ann Arbor, MI, USA.
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27
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Hao N, Donnelly AJ, Dodd IB, Shearwin KE. When push comes to shove - RNA polymerase and DNA-bound protein roadblocks. Biophys Rev 2023; 15:355-366. [PMID: 37396453 PMCID: PMC10310618 DOI: 10.1007/s12551-023-01064-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Accepted: 05/21/2023] [Indexed: 07/04/2023] Open
Abstract
In recent years, transcriptional roadblocking has emerged as a crucial regulatory mechanism in gene expression, whereby other DNA-bound obstacles can block the progression of transcribing RNA polymerase (RNAP), leading to RNAP pausing and ultimately dissociation from the DNA template. In this review, we discuss the mechanisms by which transcriptional roadblocks can impede RNAP progression, as well as how RNAP can overcome these obstacles to continue transcription. We examine different DNA-binding proteins involved in transcriptional roadblocking and their biophysical properties that determine their effectiveness in blocking RNAP progression. The catalytically dead CRISPR-Cas (dCas) protein is used as an example of an engineered programmable roadblock, and the current literature in understanding the polarity of dCas roadblocking is also discussed. Finally, we delve into a stochastic model of transcriptional roadblocking and highlight the importance of transcription factor binding kinetics and its resistance to dislodgement by an elongating RNAP in determining the strength of a roadblock.
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Affiliation(s)
- Nan Hao
- Department of Molecular and Biomedical Science, School of Biological Sciences, The University of Adelaide, Adelaide, SA 5005 Australia
| | - Alana J. Donnelly
- Department of Molecular and Biomedical Science, School of Biological Sciences, The University of Adelaide, Adelaide, SA 5005 Australia
| | - Ian B. Dodd
- Department of Molecular and Biomedical Science, School of Biological Sciences, The University of Adelaide, Adelaide, SA 5005 Australia
| | - Keith E. Shearwin
- Department of Molecular and Biomedical Science, School of Biological Sciences, The University of Adelaide, Adelaide, SA 5005 Australia
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28
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Wang Y, Zhang H, La Ferlita A, Sp N, Goryunova M, Sarchet P, Hu Z, Sorkin M, Kim A, Huang H, Zhu H, Tsung A, Pollock RE, Beane JD. Phosphorylation of IWS1 by AKT maintains liposarcoma tumor heterogeneity through preservation of cancer stem cell phenotypes and mesenchymal-epithelial plasticity. Oncogenesis 2023; 12:30. [PMID: 37237004 DOI: 10.1038/s41389-023-00469-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 04/07/2023] [Accepted: 04/17/2023] [Indexed: 05/28/2023] Open
Abstract
Chemotherapy remains the mainstay of treatment for patients with advanced liposarcoma (LPS), but response rates are only 25% and the overall survival at 5 years is dismal at 20-34%. Translation of other therapies have not been successful and there has been no significant improvement in prognosis for nearly 20 years. The aberrant activation of the phosphatidylinositol 3-kinase (PI3K)/AKT pathway has been implicated in the aggressive clinical behavior LPS and in resistance to chemotherapy, but the precise mechanism remains elusive and efforts to target AKT clinically have failed. Here we show that the AKT-mediated phosphorylation of the transcription elongation factor IWS1, promotes the maintenance of cancer stem cells in both cell and xenograft models of LPS. In addition, phosphorylation of IWS1 by AKT contributes to a "metastable" cell phenotype, characterized by mesenchymal/epithelial plasticity. The expression of phosphorylated IWS1 also promotes anchorage-dependent and independent growth, cell migration, invasion, and tumor metastasis. In patients with LPS, IWS1 expression is associated with reduced overall survival, increased frequency of recurrence, and shorter time to relapse after resection. These findings indicate that IWS1-mediated transcription elongation is an important regulator of human LPS pathobiology in an AKT-dependent manner and implicate IWS1 as an important molecular target to treat LPS.
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Affiliation(s)
- Yu Wang
- Department of Surgery, Division of Surgical Oncology, James Cancer Center, The Ohio State University, Columbus, OH, USA
- Institute of Pathology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China
| | - Hongji Zhang
- Department of Surgery, Division of Surgical Oncology, James Cancer Center, The Ohio State University, Columbus, OH, USA
| | - Alessandro La Ferlita
- Department of Cancer Biology and Genetics, James Cancer Center, The Ohio State University, Columbus, OH, USA
| | - Nipin Sp
- Department of Surgery, Division of Surgical Oncology, James Cancer Center, The Ohio State University, Columbus, OH, USA
| | - Marina Goryunova
- Department of Surgery, Division of Surgical Oncology, James Cancer Center, The Ohio State University, Columbus, OH, USA
| | - Patricia Sarchet
- Department of Surgery, Division of Surgical Oncology, James Cancer Center, The Ohio State University, Columbus, OH, USA
| | - Zhiwei Hu
- Department of Surgery, Division of Surgical Oncology, James Cancer Center, The Ohio State University, Columbus, OH, USA
| | - Michael Sorkin
- Department of Plastic and Reconstructive Surgery, James Cancer Center, The Ohio State University, Columbus, OH, USA
| | - Alex Kim
- Department of Surgery, Division of Surgical Oncology, James Cancer Center, The Ohio State University, Columbus, OH, USA
| | - Hai Huang
- Department of Surgery, Division of Surgical Oncology, James Cancer Center, The Ohio State University, Columbus, OH, USA
| | - Hua Zhu
- Department of Surgery, Division of Cardiac Surgery, Wexner Medical Center, The Ohio State University, Columbus, OH, USA
| | - Allan Tsung
- Department of Surgery, Division of Surgical Oncology, James Cancer Center, The Ohio State University, Columbus, OH, USA
| | - Raphael E Pollock
- Department of Surgery, Division of Surgical Oncology, James Cancer Center, The Ohio State University, Columbus, OH, USA
| | - Joal D Beane
- Department of Surgery, Division of Surgical Oncology, James Cancer Center, The Ohio State University, Columbus, OH, USA.
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29
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Wee LM, Tong AB, Florez Ariza AJ, Cañari-Chumpitaz C, Grob P, Nogales E, Bustamante CJ. A trailing ribosome speeds up RNA polymerase at the expense of transcript fidelity via force and allostery. Cell 2023; 186:1244-1262.e34. [PMID: 36931247 PMCID: PMC10135430 DOI: 10.1016/j.cell.2023.02.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Revised: 11/14/2022] [Accepted: 02/06/2023] [Indexed: 03/18/2023]
Abstract
In prokaryotes, translation can occur on mRNA that is being transcribed in a process called coupling. How the ribosome affects the RNA polymerase (RNAP) during coupling is not well understood. Here, we reconstituted the E. coli coupling system and demonstrated that the ribosome can prevent pausing and termination of RNAP and double the overall transcription rate at the expense of fidelity. Moreover, we monitored single RNAPs coupled to ribosomes and show that coupling increases the pause-free velocity of the polymerase and that a mechanical assisting force is sufficient to explain the majority of the effects of coupling. Also, by cryo-EM, we observed that RNAPs with a terminal mismatch adopt a backtracked conformation, while a coupled ribosome allosterically induces these polymerases toward a catalytically active anti-swiveled state. Finally, we demonstrate that prolonged RNAP pausing is detrimental to cell viability, which could be prevented by polymerase reactivation through a coupled ribosome.
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Affiliation(s)
- Liang Meng Wee
- QB3-Berkeley, Berkeley, CA, USA; Howard Hughes Medical Institute, University of California Berkeley, Berkeley, CA, USA
| | - Alexander B Tong
- QB3-Berkeley, Berkeley, CA, USA; Department of Chemistry, University of California Berkeley, Berkeley, CA, USA
| | - Alfredo Jose Florez Ariza
- QB3-Berkeley, Berkeley, CA, USA; Biophysics Graduate Group, University of California Berkeley, Berkeley, CA, USA
| | - Cristhian Cañari-Chumpitaz
- QB3-Berkeley, Berkeley, CA, USA; Department of Chemistry, University of California Berkeley, Berkeley, CA, USA; Howard Hughes Medical Institute, University of California Berkeley, Berkeley, CA, USA
| | - Patricia Grob
- QB3-Berkeley, Berkeley, CA, USA; Howard Hughes Medical Institute, University of California Berkeley, Berkeley, CA, USA; Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, CA, USA
| | - Eva Nogales
- QB3-Berkeley, Berkeley, CA, USA; Biophysics Graduate Group, University of California Berkeley, Berkeley, CA, USA; Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, CA, USA; Howard Hughes Medical Institute, University of California Berkeley, Berkeley, CA, USA; Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
| | - Carlos J Bustamante
- QB3-Berkeley, Berkeley, CA, USA; Biophysics Graduate Group, University of California Berkeley, Berkeley, CA, USA; Department of Chemistry, University of California Berkeley, Berkeley, CA, USA; Department of Physics, University of California Berkeley, Berkeley, CA, USA; Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, CA, USA; Kavli Energy Nanoscience Institute, Berkeley, CA, USA; Howard Hughes Medical Institute, University of California Berkeley, Berkeley, CA, USA; Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
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30
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Martell DJ, Merens HE, Fiorini C, Caulier A, Ulirsch JC, Ietswaart R, Choquet K, Graziadei G, Brancaleoni V, Cappellini MD, Scott C, Roberts N, Proven M, Roy NB, Babbs C, Higgs DR, Sankaran VG, Churchman LS. RNA Polymerase II pausing temporally coordinates cell cycle progression and erythroid differentiation. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2023:2023.03.03.23286760. [PMID: 36945604 PMCID: PMC10029049 DOI: 10.1101/2023.03.03.23286760] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
The controlled release of promoter-proximal paused RNA polymerase II (Pol II) into productive elongation is a major step in gene regulation. However, functional analysis of Pol II pausing is difficult because factors that regulate pause release are almost all essential. In this study, we identified heterozygous loss-of-function mutations in SUPT5H , which encodes SPT5, in individuals with β-thalassemia unlinked to HBB mutations. During erythropoiesis in healthy human cells, cell cycle genes were highly paused at the transition from progenitors to precursors. When the pathogenic mutations were recapitulated by SUPT5H editing, Pol II pause release was globally disrupted, and the transition from progenitors to precursors was delayed, marked by a transient lag in erythroid-specific gene expression and cell cycle kinetics. Despite this delay, cells terminally differentiate, and cell cycle phase distributions normalize. Therefore, hindering pause release perturbs proliferation and differentiation dynamics at a key transition during erythropoiesis, revealing a role for Pol II pausing in the temporal coordination between the cell cycle and differentiation.
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Affiliation(s)
- Danya J Martell
- Harvard University, Department of Genetics, Boston, MA
- Division of Hematology/Oncology, Boston Children's Hospital, Harvard Medical School, Boston, MA
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA
- Broad Institute of MIT and Harvard, Cambridge, MA
| | - Hope E Merens
- Harvard University, Department of Genetics, Boston, MA
| | - Claudia Fiorini
- Division of Hematology/Oncology, Boston Children's Hospital, Harvard Medical School, Boston, MA
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA
- Broad Institute of MIT and Harvard, Cambridge, MA
| | - Alexis Caulier
- Division of Hematology/Oncology, Boston Children's Hospital, Harvard Medical School, Boston, MA
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA
- Broad Institute of MIT and Harvard, Cambridge, MA
| | - Jacob C Ulirsch
- Division of Hematology/Oncology, Boston Children's Hospital, Harvard Medical School, Boston, MA
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA
- Broad Institute of MIT and Harvard, Cambridge, MA
| | | | | | - Giovanna Graziadei
- Department of Clinical Sciences and Community, University of Milan, IRCCS Ca'Granda Foundation Maggiore Policlinico Hospital, Milan, Italy
| | - Valentina Brancaleoni
- Department of Clinical Sciences and Community, University of Milan, IRCCS Ca'Granda Foundation Maggiore Policlinico Hospital, Milan, Italy
| | - Maria Domenica Cappellini
- Department of Clinical Sciences and Community, University of Milan, IRCCS Ca'Granda Foundation Maggiore Policlinico Hospital, Milan, Italy
| | - Caroline Scott
- MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom
| | - Nigel Roberts
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Melanie Proven
- Oxford Genetics Laboratories, Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| | - Noémi Ba Roy
- MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom
- NIHR Oxford Biomedical Research Centre and BRC/NHS Translational Molecular Diagnostics Centre, John Radcliffe Hospital, Oxford, UK
- Department of Haematology, Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| | - Christian Babbs
- MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom
| | - Douglas R Higgs
- MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom
| | - Vijay G Sankaran
- Division of Hematology/Oncology, Boston Children's Hospital, Harvard Medical School, Boston, MA
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA
- Broad Institute of MIT and Harvard, Cambridge, MA
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31
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Wang Z, Mačáková M, Bugai A, Kuznetsov SG, Hassinen A, Lenasi T, Potdar S, Friedel CC, Barborič M. P-TEFb promotes cell survival upon p53 activation by suppressing intrinsic apoptosis pathway. Nucleic Acids Res 2023; 51:1687-1706. [PMID: 36727434 PMCID: PMC9976905 DOI: 10.1093/nar/gkad001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Revised: 12/27/2022] [Accepted: 01/03/2023] [Indexed: 02/03/2023] Open
Abstract
Positive transcription elongation factor b (P-TEFb) is the crucial player in RNA polymerase II (Pol II) pause release that has emerged as a promising target in cancer. Because single-agent therapy may fail to deliver durable clinical response, targeting of P-TEFb shall benefit when deployed as a combination therapy. We screened a comprehensive oncology library and identified clinically relevant antimetabolites and Mouse double minute 2 homolog (MDM2) inhibitors as top compounds eliciting p53-dependent death of colorectal cancer cells in synergy with selective inhibitors of P-TEFb. While the targeting of P-TEFb augments apoptosis by anti-metabolite 5-fluorouracil, it switches the fate of cancer cells by the non-genotoxic MDM2 inhibitor Nutlin-3a from cell-cycle arrest to apoptosis. Mechanistically, the fate switching is enabled by the induction of p53-dependent pro-apoptotic genes and repression of P-TEFb-dependent pro-survival genes of the PI3K-AKT signaling cascade, which stimulates caspase 9 and intrinsic apoptosis pathway in BAX/BAK-dependent manner. Finally, combination treatments trigger apoptosis of cancer cell spheroids. Together, co-targeting of P-TEFb and suppressors of intrinsic apoptosis could become a viable strategy to eliminate cancer cells.
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Affiliation(s)
- Zhijia Wang
- Department of Biochemistry and Developmental Biology, University of Helsinki, Helsinki FIN-00014, Finland
| | - Monika Mačáková
- Department of Biochemistry and Developmental Biology, University of Helsinki, Helsinki FIN-00014, Finland
| | - Andrii Bugai
- Department of Biochemistry and Developmental Biology, University of Helsinki, Helsinki FIN-00014, Finland.,Department of Molecular Biology and Genetics, Aarhus University, 8000 Aarhus C, Denmark
| | - Sergey G Kuznetsov
- High-Throughput Biomedicine Unit (HTB), Institute for Molecular Medicine Finland (FIMM), University of Helsinki, Helsinki FIN-00014, Finland
| | - Antti Hassinen
- High Content Imaging and Analysis Unit (HCA), Institute for Molecular Medicine Finland (FIMM), University of Helsinki, Helsinki FIN-00014, Finland
| | - Tina Lenasi
- Department of Biochemistry and Developmental Biology, University of Helsinki, Helsinki FIN-00014, Finland
| | - Swapnil Potdar
- High-Throughput Biomedicine Unit (HTB), Institute for Molecular Medicine Finland (FIMM), University of Helsinki, Helsinki FIN-00014, Finland
| | - Caroline C Friedel
- Institute for Informatics, Ludwig-Maximilians-Universität München, 80333 Munich, Germany
| | - Matjaž Barborič
- Department of Biochemistry and Developmental Biology, University of Helsinki, Helsinki FIN-00014, Finland
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Lee SA, Kristjánsdóttir K, Kwak H. Revealing eRNA interactions: TF dependency and convergent cooperativity. RESEARCH SQUARE 2023:rs.3.rs-2592357. [PMID: 36909657 PMCID: PMC10002804 DOI: 10.21203/rs.3.rs-2592357/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/04/2023]
Abstract
Enhancer RNAs (eRNAs) are non-coding RNAs produced from transcriptional enhancers that are highly correlated with their activities. Using capped nascent RNA sequencing (PRO-cap) dataset in human lymphoblastoid cell lines across individuals, we identified inter-individual variation of expression in over 80 thousand transcribed transcriptional regulatory elements (tTREs), in both enhancers and promoters. Co-expression analysis of eRNAs from tTREs across individuals revealed how enhancers interact with each other and with promoters. Mid-to-long range interactions showed distance-dependent decay, which was modified by TF occupancy. In particular, we found a class of 'bivalent' TFs, including Cohesin, which both facilitates and insulates the interaction between enhancers and/or promoters depending on the topology. In short ranges, we observed strand specific interactions between nearby eRNAs in both convergent or divergent orientations. Our finding supports a cooperative convergent eRNA model, which is compatible with eRNA remodeling neighboring enhancers rather than interfering with each other. Therefore, our approach to infer functional interactions from co-expression analyses provided novel insights into the principles of enhancer interactions depending on the distance, orientation, and the binding landscapes of TFs.
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Nabavizadeh N, Bressin A, Shboul M, Moreno Traspas R, Chia PH, Bonnard C, Szenker‐Ravi E, Sarıbaş B, Beillard E, Altunoglu U, Hojati Z, Drutman S, Freier S, El‐Khateeb M, Fathallah R, Casanova J, Soror W, Arafat A, Escande‐Beillard N, Mayer A, Reversade B. A progeroid syndrome caused by a deep intronic variant in TAPT1 is revealed by RNA/SI-NET sequencing. EMBO Mol Med 2023; 15:e16478. [PMID: 36652330 PMCID: PMC9906387 DOI: 10.15252/emmm.202216478] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 12/13/2022] [Accepted: 12/14/2022] [Indexed: 01/19/2023] Open
Abstract
Exome sequencing has introduced a paradigm shift for the identification of germline variations responsible for Mendelian diseases. However, non-coding regions, which make up 98% of the genome, cannot be captured. The lack of functional annotation for intronic and intergenic variants makes RNA-seq a powerful companion diagnostic. Here, we illustrate this point by identifying six patients with a recessive Osteogenesis Imperfecta (OI) and neonatal progeria syndrome. By integrating homozygosity mapping and RNA-seq, we delineated a deep intronic TAPT1 mutation (c.1237-52 G>A) that segregated with the disease. Using SI-NET-seq, we document that TAPT1's nascent transcription was not affected in patients' fibroblasts, indicating instead that this variant leads to an alteration of pre-mRNA processing. Predicted to serve as an alternative splicing branchpoint, this mutation enhances TAPT1 exon 12 skipping, creating a protein-null allele. Additionally, our study reveals dysregulation of pathways involved in collagen and extracellular matrix biology in disease-relevant cells. Overall, our work highlights the power of transcriptomic approaches in deciphering the repercussions of non-coding variants, as well as in illuminating the molecular mechanisms of human diseases.
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Affiliation(s)
- Nasrinsadat Nabavizadeh
- Laboratory of Human Genetics & TherapeuticsGenome Institute of Singapore, A*STARSingapore CitySingapore
- Division of Genetics, Department of Cell and Molecular Biology & Microbiology, Faculty of Biological Science and TechnologyUniversity of IsfahanIsfahanIran
- Medical Genetics DepartmentKoç University School of MedicineIstanbulTurkey
| | | | - Mohammad Shboul
- Department of Medical Laboratory SciencesJordan University of Science and TechnologyIrbidJordan
| | - Ricardo Moreno Traspas
- Laboratory of Human Genetics & TherapeuticsGenome Institute of Singapore, A*STARSingapore CitySingapore
| | - Poh Hui Chia
- Laboratory of Human Genetics & TherapeuticsGenome Institute of Singapore, A*STARSingapore CitySingapore
| | - Carine Bonnard
- Model Development, A*STAR Skin Research Labs (A*SRL)Singapore CitySingapore
| | - Emmanuelle Szenker‐Ravi
- Laboratory of Human Genetics & TherapeuticsGenome Institute of Singapore, A*STARSingapore CitySingapore
| | - Burak Sarıbaş
- Laboratory of Human Genetics & TherapeuticsGenome Institute of Singapore, A*STARSingapore CitySingapore
- Medical Genetics DepartmentKoç University School of MedicineIstanbulTurkey
| | | | - Umut Altunoglu
- Medical Genetics DepartmentKoç University School of MedicineIstanbulTurkey
| | - Zohreh Hojati
- Division of Genetics, Department of Cell and Molecular Biology & Microbiology, Faculty of Biological Science and TechnologyUniversity of IsfahanIsfahanIran
| | - Scott Drutman
- St. Giles Laboratory of Human Genetics of Infectious Diseases, Rockefeller BranchRockefeller UniversityNew YorkNYUSA
| | - Susanne Freier
- Max Planck Institute for Molecular GeneticsBerlinGermany
| | | | - Rajaa Fathallah
- National Center for Diabetes, Endocrinology and GeneticsAmmanJordan
| | - Jean‐Laurent Casanova
- St. Giles Laboratory of Human Genetics of Infectious Diseases, Rockefeller BranchRockefeller UniversityNew YorkNYUSA
- Laboratory of Human Genetics of Infectious Diseases, Necker BranchINSERM U1163, Necker Hospital for Sick ChildrenParisFrance
- Imagine InstituteUniversity of ParisParisFrance
- Howard Hughes Medical InstituteNew YorkNYUSA
- Pediatric Hematology and Immunology UnitNecker Hospital for Sick ChildrenParisFrance
| | - Wesam Soror
- National Center for Diabetes, Endocrinology and GeneticsAmmanJordan
| | - Alaa Arafat
- National Center for Diabetes, Endocrinology and GeneticsAmmanJordan
| | - Nathalie Escande‐Beillard
- Medical Genetics DepartmentKoç University School of MedicineIstanbulTurkey
- Institute of Molecular and Cell Biology, A*STARSingapore CitySingapore
| | - Andreas Mayer
- Max Planck Institute for Molecular GeneticsBerlinGermany
| | - Bruno Reversade
- Laboratory of Human Genetics & TherapeuticsGenome Institute of Singapore, A*STARSingapore CitySingapore
- Medical Genetics DepartmentKoç University School of MedicineIstanbulTurkey
- Institute of Molecular and Cell Biology, A*STARSingapore CitySingapore
- Department of PaediatricsNational University of SingaporeSingapore CitySingapore
- Smart‐Health Initiative, BESE, KAUSTThuwalKingdom of Saudi Arabia
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34
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MDC1 maintains active elongation complexes of RNA polymerase II. Cell Rep 2023; 42:111979. [PMID: 36640322 DOI: 10.1016/j.celrep.2022.111979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 10/04/2022] [Accepted: 12/23/2022] [Indexed: 01/13/2023] Open
Abstract
The role of MDC1 in the DNA damage response has been extensively studied; however, its impact on other cellular processes is not well understood. Here, we describe the role of MDC1 in transcription as a regulator of RNA polymerase II (RNAPII). Depletion of MDC1 causes a genome-wide reduction in the abundance of actively engaged RNAPII elongation complexes throughout the gene body of protein-encoding genes under unperturbed conditions. Decreased engaged RNAPII subsequently alters the assembly of the spliceosome complex on chromatin, leading to changes in pre-mRNA splicing. Mechanistically, the S/TQ domain of MDC1 modulates RNAPII-mediated transcription. Upon genotoxic stress, MDC1 promotes the abundance of engaged RNAPII complexes at DNA breaks, thereby stimulating nascent transcription at the damaged sites. Of clinical relevance, cancer cells lacking MDC1 display hypersensitivity to RNAPII inhibitors. Overall, we unveil a role of MDC1 in RNAPII-mediated transcription with potential implications for cancer treatment.
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Wu H, Liu M, Zhang P, Zhang H. iEnhancer-SKNN: a stacking ensemble learning-based method for enhancer identification and classification using sequence information. Brief Funct Genomics 2023; 22:302-311. [PMID: 36715222 DOI: 10.1093/bfgp/elac057] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Revised: 12/01/2022] [Accepted: 12/13/2022] [Indexed: 01/31/2023] Open
Abstract
Enhancers, a class of distal cis-regulatory elements located in the non-coding region of DNA, play a key role in gene regulation. It is difficult to identify enhancers from DNA sequence data because enhancers are freely distributed in the non-coding region, with no specific sequence features, and having a long distance with the targeted promoters. Therefore, this study presents a stacking ensemble learning method to accurately identify enhancers and classify enhancers into strong and weak enhancers. Firstly, we obtain the fusion feature matrix by fusing the four features of Kmer, PseDNC, PCPseDNC and Z-Curve9. Secondly, five K-Nearest Neighbor (KNN) models with different parameters are trained as the base model, and the Logistic Regression algorithm is utilized as the meta-model. Thirdly, the stacking ensemble learning strategy is utilized to construct a two-layer model based on the base model and meta-model to train the preprocessed feature sets. The proposed method, named iEnhancer-SKNN, is a two-layer prediction model, in which the function of the first layer is to predict whether the given DNA sequences are enhancers or non-enhancers, and the function of the second layer is to distinguish whether the predicted enhancers are strong enhancers or weak enhancers. The performance of iEnhancer-SKNN is evaluated on the independent testing dataset and the results show that the proposed method has better performance in predicting enhancers and their strength. In enhancer identification, iEnhancer-SKNN achieves an accuracy of 81.75%, an improvement of 1.35% to 8.75% compared with other predictors, and in enhancer classification, iEnhancer-SKNN achieves an accuracy of 80.50%, an improvement of 5.5% to 25.5% compared with other predictors. Moreover, we identify key transcription factor binding site motifs in the enhancer regions and further explore the biological functions of the enhancers and these key motifs. Source code and data can be downloaded from https://github.com/HaoWuLab-Bioinformatics/iEnhancer-SKNN.
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Affiliation(s)
- Hao Wu
- College of Information Engineering, Northwest A&F University, Yangling, 712100, Shaanxi, China.,School of Software, Shandong University, Jinan, 250101, Shandong, China
| | - Mengdi Liu
- College of Information Engineering, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Pengyu Zhang
- College of Information Engineering, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Hongming Zhang
- College of Information Engineering, Northwest A&F University, Yangling, 712100, Shaanxi, China
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36
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Kumar D, Sahoo SS, Chauss D, Kazemian M, Afzali B. Non-coding RNAs in immunoregulation and autoimmunity: Technological advances and critical limitations. J Autoimmun 2023; 134:102982. [PMID: 36592512 PMCID: PMC9908861 DOI: 10.1016/j.jaut.2022.102982] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 12/11/2022] [Accepted: 12/15/2022] [Indexed: 01/02/2023]
Abstract
Immune cell function is critically dependent on precise control over transcriptional output from the genome. In this respect, integration of environmental signals that regulate gene expression, specifically by transcription factors, enhancer DNA elements, genome topography and non-coding RNAs (ncRNAs), are key components. The first three have been extensively investigated. Even though non-coding RNAs represent the vast majority of cellular RNA species, this class of RNA remains historically understudied. This is partly because of a lag in technological and bioinformatic innovations specifically capable of identifying and accurately measuring their expression. Nevertheless, recent progress in this domain has enabled a profusion of publications identifying novel sub-types of ncRNAs and studies directly addressing the function of ncRNAs in human health and disease. Many ncRNAs, including circular and enhancer RNAs, have now been demonstrated to play key functions in the regulation of immune cells and to show associations with immune-mediated diseases. Some ncRNAs may function as biomarkers of disease, aiding in diagnostics and in estimating response to treatment, while others may play a direct role in the pathogenesis of disease. Importantly, some are relatively stable and are amenable to therapeutic targeting, for example through gene therapy. Here, we provide an overview of ncRNAs and review technological advances that enable their study and hold substantial promise for the future. We provide context-specific examples by examining the associations of ncRNAs with four prototypical human autoimmune diseases, specifically rheumatoid arthritis, psoriasis, inflammatory bowel disease and multiple sclerosis. We anticipate that the utility and mechanistic roles of these ncRNAs in autoimmunity will be further elucidated in the near future.
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Affiliation(s)
- Dhaneshwar Kumar
- Immunoregulation Section, Kidney Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), NIH, Bethesda, MD, USA
| | - Subhransu Sekhar Sahoo
- Departments of Biochemistry and Computer Science, Purdue University, West Lafayette, IN, USA
| | - Daniel Chauss
- Immunoregulation Section, Kidney Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), NIH, Bethesda, MD, USA
| | - Majid Kazemian
- Departments of Biochemistry and Computer Science, Purdue University, West Lafayette, IN, USA
| | - Behdad Afzali
- Immunoregulation Section, Kidney Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), NIH, Bethesda, MD, USA.
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37
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Eischer N, Arnold M, Mayer A. Emerging roles of BET proteins in transcription and co-transcriptional RNA processing. WILEY INTERDISCIPLINARY REVIEWS. RNA 2023; 14:e1734. [PMID: 35491403 DOI: 10.1002/wrna.1734] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 04/06/2022] [Accepted: 04/09/2022] [Indexed: 01/31/2023]
Abstract
Transcription by RNA polymerase II (Pol II) gives rise to all nuclear protein-coding and a large set of non-coding RNAs, and is strictly regulated and coordinated with RNA processing. Bromodomain and extraterminal (BET) family proteins including BRD2, BRD3, and BRD4 have been implicated in the regulation of Pol II transcription in mammalian cells. However, only recent technological advances have allowed the analysis of direct functions of individual BET proteins with high precision in cells. These studies shed new light on the molecular mechanisms of transcription control by BET proteins challenging previous longstanding views. The most studied BET protein, BRD4, emerges as a master regulator of transcription elongation with roles also in coupling nascent transcription with RNA processing. In contrast, BRD2 is globally required for the formation of transcriptional boundaries to restrict enhancer activity to nearby genes. Although these recent findings suggest non-redundant functions of BRD4 and BRD2 in Pol II transcription, more research is needed for further clarification. Little is known about the roles of BRD3. Here, we illuminate experimental work that has initially linked BET proteins to Pol II transcription in mammalian cells, outline main methodological breakthroughs that have strongly advanced the understanding of BET protein functions, and discuss emerging roles of individual BET proteins in transcription and transcription-coupled RNA processing. Finally, we propose an updated model for the function of BRD4 in transcription and co-transcriptional RNA maturation. This article is categorized under: RNA Processing > 3' End Processing RNA Processing > Splicing Regulation/Alternative Splicing.
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Affiliation(s)
- Nicole Eischer
- Otto-Warburg-Laboratory, Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - Mirjam Arnold
- Otto-Warburg-Laboratory, Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - Andreas Mayer
- Otto-Warburg-Laboratory, Max Planck Institute for Molecular Genetics, Berlin, Germany
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38
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Abe K, Schauer T, Torres-Padilla ME. Distinct patterns of RNA polymerase II and transcriptional elongation characterize mammalian genome activation. Cell Rep 2022; 41:111865. [PMID: 36577375 DOI: 10.1016/j.celrep.2022.111865] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Revised: 09/08/2022] [Accepted: 09/30/2022] [Indexed: 12/28/2022] Open
Abstract
How transcription is regulated as development commences is fundamental to understand how the transcriptionally silent mature gametes are reprogrammed. The embryonic genome is activated for the first time during zygotic genome activation (ZGA). How RNA polymerase II (Pol II) and productive elongation are regulated during this process remains elusive. Here, we generate genome-wide maps of Serine 5 and Serine 2-phosphorylated Pol II during and after ZGA in mouse embryos. We find that both phosphorylated Pol II forms display similar distributions across genes during ZGA, with typical elongation enrichment of Pol II emerging after ZGA. Serine 2-phosphorylated Pol II occurs at genes prior to their activation, suggesting that Serine 2 phosphorylation may prime gene expression. Functional perturbations demonstrate that CDK9 and SPT5 are major ZGA regulators and that SPT5 prevents precocious activation of some genes. Overall, our work sheds molecular insights into transcriptional regulation at the beginning of mammalian development.
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Affiliation(s)
- Kenichiro Abe
- Institute of Epigenetics and Stem Cells, Helmholtz Zentrum München, 81377 München, Germany
| | - Tamas Schauer
- Institute of Epigenetics and Stem Cells, Helmholtz Zentrum München, 81377 München, Germany; Bioinformatics Unit, Biomedical Center, Ludwig-Maximilians-University, 82152 Planegg-Martinsried, Germany
| | - Maria-Elena Torres-Padilla
- Institute of Epigenetics and Stem Cells, Helmholtz Zentrum München, 81377 München, Germany; Faculty of Biology, Ludwig-Maximilians Universität, München, Germany.
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39
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Gregersen LH, Mitter R, Svejstrup JQ. Elongation factor-specific capture of RNA polymerase II complexes. CELL REPORTS METHODS 2022; 2:100368. [PMID: 36590686 PMCID: PMC9795356 DOI: 10.1016/j.crmeth.2022.100368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 10/25/2022] [Accepted: 11/18/2022] [Indexed: 12/13/2022]
Abstract
Transcription of protein-coding genes is regulated by dynamic association of co-factors with RNA polymerase II (RNAPII). The function of these factors and their relationship with RNAPII is often poorly understood. Here, we present an approach for elongation-factor-specific mNET capture (ELCAP) of RNAPII complexes for sequencing and mass spectrometry analysis aimed at investigating the function of such RNAPII regulatory proteins. As proof of principle, we apply ELCAP to the RNAPII-associated proteins SCAF4 and SCAF8, which share an essential role as mRNA anti-terminators but have individual roles at the 3' end of genes. Mass spectrometry analysis shows that both SCAF4 and SCAF8 are part of RNAPII elongation complexes containing 3' end processing factors but depleted of splicing components. Importantly, the ELCAP sequencing (ELCAP-seq) profiles of SCAF4- and SCAF8-RNAPII complexes nicely reflect their function as mRNA-anti-terminators and their competing functions at the end of genes, where they prevent or promote transcriptional readthrough.
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Affiliation(s)
- Lea H. Gregersen
- Department of Cellular and Molecular Medicine, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen, Denmark
| | - Richard Mitter
- Bioinformatics and Biostatistics, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Jesper Q. Svejstrup
- Department of Cellular and Molecular Medicine, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen, Denmark
- Mechanisms of Transcription Laboratory, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
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40
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Zeng Y, Fair BJ, Zeng H, Krishnamohan A, Hou Y, Hall JM, Ruthenburg AJ, Li YI, Staley JP. Profiling lariat intermediates reveals genetic determinants of early and late co-transcriptional splicing. Mol Cell 2022; 82:4681-4699.e8. [PMID: 36435176 PMCID: PMC10448999 DOI: 10.1016/j.molcel.2022.11.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Revised: 09/10/2022] [Accepted: 11/02/2022] [Indexed: 11/27/2022]
Abstract
Long introns with short exons in vertebrate genes are thought to require spliceosome assembly across exons (exon definition), rather than introns, thereby requiring transcription of an exon to splice an upstream intron. Here, we developed CoLa-seq (co-transcriptional lariat sequencing) to investigate the timing and determinants of co-transcriptional splicing genome wide. Unexpectedly, 90% of all introns, including long introns, can splice before transcription of a downstream exon, indicating that exon definition is not obligatory for most human introns. Still, splicing timing varies dramatically across introns, and various genetic elements determine this variation. Strong U2AF2 binding to the polypyrimidine tract predicts early splicing, explaining exon definition-independent splicing. Together, our findings question the essentiality of exon definition and reveal features beyond intron and exon length that are determinative for splicing timing.
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Affiliation(s)
- Yi Zeng
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL 60637, USA
| | - Benjamin J Fair
- Department of Medicine, University of Chicago, Chicago, IL 60637, USA
| | - Huilin Zeng
- 855 Jefferson Ave. Redwood City, CA 94063, USA
| | - Aiswarya Krishnamohan
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL 60637, USA
| | - Yichen Hou
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL 60637, USA
| | - Johnathon M Hall
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL 60637, USA
| | - Alexander J Ruthenburg
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL 60637, USA; Department of Biochemistry & Molecular Biology, University of Chicago, Chicago, IL 60637, USA
| | - Yang I Li
- Department of Medicine, University of Chicago, Chicago, IL 60637, USA; Department of Human Genetics, University of Chicago, Chicago, IL 60637, USA.
| | - Jonathan P Staley
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL 60637, USA.
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41
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Zhang Q, Zhao F, Wu Z, Zhu D. A simple and robust method for isolating and analyzing chromatin-bound RNAs in Arabidopsis. PLANT METHODS 2022; 18:135. [PMID: 36510301 PMCID: PMC9743689 DOI: 10.1186/s13007-022-00967-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/24/2022] [Accepted: 11/30/2022] [Indexed: 06/17/2023]
Abstract
BACKGROUND Chromatin-bound RNAs are the primary product of transcription that undergo on-chromatin processing such as capping, splicing, and polyadenylation. These processing steps then determine the fate of RNAs. Albeit its vital importance, a simple and robust method for isolating different fractions of chromatin-bound RNAs is missing in plants. RESULT Here, we describe our updated method and the associated step-by-step protocol for chromatin-bound RNAs isolation in A. thaliana. The chromatin-bound RNAs isolation is based on the 1 M UREA wash that removes the majority of non-chromatin-associated proteins from the nucleus, as previously developed in mammalian cells. On-demand, the isolated chromatin-bound RNAs can be either used directly for gene-specific analysis or subject to further rRNA removal and also the optional polyadenylated RNA removal, followed by high-throughput sequencing. Detailed protocols for these procedures are also provided. Comparison of sequencing results of chromatin-bound RNAs with and without polyadenylated RNA removal revealed that a small fraction of CB-RNAs is polyadenylated but not yet fully spliced, representing RNA-processing intermediate on-chromatin. CONCLUSION This optimized chromatin-bound RNAs purification method is simple and robust and can be used to study transcription and its-coupled RNA processing in plants.
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Affiliation(s)
- Qiqi Zhang
- Harbin Institute of Technology, Harbin, 150001, China
- Key Laboratory of Molecular Design for Plant Cell Factory of Guangdong Higher Education Institutes, Institute of Plant and Food Research, Department of Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Fengli Zhao
- Key Laboratory of Molecular Design for Plant Cell Factory of Guangdong Higher Education Institutes, Institute of Plant and Food Research, Department of Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Zhe Wu
- Key Laboratory of Molecular Design for Plant Cell Factory of Guangdong Higher Education Institutes, Institute of Plant and Food Research, Department of Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, 518055, China.
| | - Danling Zhu
- Key Laboratory of Molecular Design for Plant Cell Factory of Guangdong Higher Education Institutes, Institute of Plant and Food Research, Department of Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, 518055, China.
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42
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Herbert A. Nucleosomes and flipons exchange energy to alter chromatin conformation, the readout of genomic information, and cell fate. Bioessays 2022; 44:e2200166. [DOI: 10.1002/bies.202200166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 09/24/2022] [Accepted: 09/28/2022] [Indexed: 11/27/2022]
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43
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Kitamura K, Suzuki H, Abe R, Inohara H, Kaneda Y, Takahashi H, Nimura K. Dual function of SF3B2 on chromatin and RNA to regulate transcription in head and neck squamous cell carcinoma. Cell Biosci 2022; 12:92. [PMID: 35715826 PMCID: PMC9206271 DOI: 10.1186/s13578-022-00812-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2022] [Accepted: 05/11/2022] [Indexed: 11/13/2022] Open
Abstract
RNA is spliced concomitantly with transcription and the process is organized by RNA splicing factors, transcriptional regulators, and chromatin regulators. RNA is spliced in close proximity to transcription machinery. Hence, some RNA splicing factors may play a role in transcription. Here, we show that the splicing factor SF3B2 binds to gene regulatory elements and mRNA to modulate transcription and RNA stability in head and neck squamous cell carcinoma cells. High SF3B2 expression leads to poor prognosis in patients with head and neck squamous cell carcinoma and to progression of tumor growth in mice. SF3B2 promotes tumor growth, owing to its involvement in activation of gene expression associated with mitochondrial electron transport and transcription regulatory region DNA binding. SF3B2 is enriched around the promoter element on chromatin and the transcription termination site on RNA. SF3B2 is involved in the regulation of RNA stability. According to the SF3B2-binding profile, SF3B2 regulates RNA polymerase II activity, in addition to regulating RNA splicing. Mechanistically, SF3B2 promotes the binding of structural maintenance of chromosomes 1A and CCCTC-binding factor (CTCF) to the SF3B2-binding genomic regions. SF3B2 also modulates CTCF transcriptional activity. Our findings indicate that SF3B2 has a dual function in both transcription and RNA stability, leading to head and neck squamous cell carcinoma progression.
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44
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Liao M, Zhao JP, Tian J, Zheng CH. iEnhancer-DCLA: using the original sequence to identify enhancers and their strength based on a deep learning framework. BMC Bioinformatics 2022; 23:480. [PMCID: PMC9664816 DOI: 10.1186/s12859-022-05033-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Accepted: 11/02/2022] [Indexed: 11/16/2022] Open
Abstract
AbstractEnhancers are small regions of DNA that bind to proteins, which enhance the transcription of genes. The enhancer may be located upstream or downstream of the gene. It is not necessarily close to the gene to be acted on, because the entanglement structure of chromatin allows the positions far apart in the sequence to have the opportunity to contact each other. Therefore, identifying enhancers and their strength is a complex and challenging task. In this article, a new prediction method based on deep learning is proposed to identify enhancers and enhancer strength, called iEnhancer-DCLA. Firstly, we use word2vec to convert k-mers into number vectors to construct an input matrix. Secondly, we use convolutional neural network and bidirectional long short-term memory network to extract sequence features, and finally use the attention mechanism to extract relatively important features. In the task of predicting enhancers and their strengths, this method has improved to a certain extent in most evaluation indexes. In summary, we believe that this method provides new ideas in the analysis of enhancers.
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Luan J, Vermunt MW, Syrett CM, Coté A, Tome JM, Zhang H, Huang A, Luppino JM, Keller CA, Giardine BM, Zhang S, Dunagin MC, Zhang Z, Joyce EF, Lis JT, Raj A, Hardison RC, Blobel GA. CTCF blocks antisense transcription initiation at divergent promoters. Nat Struct Mol Biol 2022; 29:1136-1144. [PMID: 36369346 DOI: 10.1101/2021.10.30.465508] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Accepted: 09/29/2022] [Indexed: 05/26/2023]
Abstract
Transcription at most promoters is divergent, initiating at closely spaced oppositely oriented core promoters to produce sense transcripts along with often unstable upstream antisense transcripts (uasTrx). How antisense transcription is regulated and to what extent it is coordinated with sense transcription is not well understood. Here, by combining acute degradation of the multi-functional transcription factor CTCF and nascent transcription measurements, we find that CTCF specifically suppresses antisense but not sense transcription at hundreds of divergent promoters. Primary transcript RNA-FISH shows that CTCF lowers burst fraction but not burst intensity of uasTrx and that co-bursting of sense and antisense transcripts is disfavored. Genome editing, chromatin conformation studies and high-resolution transcript mapping revealed that precisely positioned CTCF directly suppresses the initiation of uasTrx, in a manner independent of its architectural function. In sum, CTCF shapes the transcriptional landscape in part by suppressing upstream antisense transcription.
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Affiliation(s)
- Jing Luan
- Medical Scientist Training Program, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Marit W Vermunt
- Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Camille M Syrett
- Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
- Clarion Healthcare, LLC, Boston, MA, USA
| | - Allison Coté
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA
- Department of Genetics, University of Pennsylvania, Philadelphia, PA, USA
| | - Jacob M Tome
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA
- Shape Therapeutics Inc, Seattle, WA, USA
| | - Haoyue Zhang
- Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
- Institute of Molecular Physiology, Shenzhen Bay Laboratory, Shenzhen, China
| | - Anran Huang
- Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Jennifer M Luppino
- Department of Genetics, University of Pennsylvania, Philadelphia, PA, USA
| | - Cheryl A Keller
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, PA, USA
| | - Belinda M Giardine
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, PA, USA
| | - Shiping Zhang
- Department of Biomedical and Health Informatics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Margaret C Dunagin
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA
| | - Zhe Zhang
- Department of Biomedical and Health Informatics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Eric F Joyce
- Department of Genetics, University of Pennsylvania, Philadelphia, PA, USA
| | - John T Lis
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA
| | - Arjun Raj
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA
- Department of Genetics, University of Pennsylvania, Philadelphia, PA, USA
| | - Ross C Hardison
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, PA, USA
| | - Gerd A Blobel
- Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA.
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46
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Luan J, Vermunt MW, Syrett CM, Coté A, Tome JM, Zhang H, Huang A, Luppino JM, Keller CA, Giardine BM, Zhang S, Dunagin MC, Zhang Z, Joyce EF, Lis JT, Raj A, Hardison RC, Blobel GA. CTCF blocks antisense transcription initiation at divergent promoters. Nat Struct Mol Biol 2022; 29:1136-1144. [PMID: 36369346 PMCID: PMC10015438 DOI: 10.1038/s41594-022-00855-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Accepted: 09/29/2022] [Indexed: 11/13/2022]
Abstract
Transcription at most promoters is divergent, initiating at closely spaced oppositely oriented core promoters to produce sense transcripts along with often unstable upstream antisense transcripts (uasTrx). How antisense transcription is regulated and to what extent it is coordinated with sense transcription is not well understood. Here, by combining acute degradation of the multi-functional transcription factor CTCF and nascent transcription measurements, we find that CTCF specifically suppresses antisense but not sense transcription at hundreds of divergent promoters. Primary transcript RNA-FISH shows that CTCF lowers burst fraction but not burst intensity of uasTrx and that co-bursting of sense and antisense transcripts is disfavored. Genome editing, chromatin conformation studies and high-resolution transcript mapping revealed that precisely positioned CTCF directly suppresses the initiation of uasTrx, in a manner independent of its architectural function. In sum, CTCF shapes the transcriptional landscape in part by suppressing upstream antisense transcription.
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Affiliation(s)
- Jing Luan
- Medical Scientist Training Program, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Marit W Vermunt
- Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Camille M Syrett
- Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
- Clarion Healthcare, LLC, Boston, MA, USA
| | - Allison Coté
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA
- Department of Genetics, University of Pennsylvania, Philadelphia, PA, USA
| | - Jacob M Tome
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA
- Shape Therapeutics Inc, Seattle, WA, USA
| | - Haoyue Zhang
- Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
- Institute of Molecular Physiology, Shenzhen Bay Laboratory, Shenzhen, China
| | - Anran Huang
- Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Jennifer M Luppino
- Department of Genetics, University of Pennsylvania, Philadelphia, PA, USA
| | - Cheryl A Keller
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, PA, USA
| | - Belinda M Giardine
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, PA, USA
| | - Shiping Zhang
- Department of Biomedical and Health Informatics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Margaret C Dunagin
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA
| | - Zhe Zhang
- Department of Biomedical and Health Informatics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Eric F Joyce
- Department of Genetics, University of Pennsylvania, Philadelphia, PA, USA
| | - John T Lis
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA
| | - Arjun Raj
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA
- Department of Genetics, University of Pennsylvania, Philadelphia, PA, USA
| | - Ross C Hardison
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, PA, USA
| | - Gerd A Blobel
- Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA.
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47
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Sledziowska M, Winczura K, Jones M, Almaghrabi R, Mischo H, Hebenstreit D, Garcia P, Grzechnik P. Non-coding RNAs associated with Prader-Willi syndrome regulate transcription of neurodevelopmental genes in human induced pluripotent stem cells. Hum Mol Genet 2022; 32:608-620. [PMID: 36084040 PMCID: PMC9896466 DOI: 10.1093/hmg/ddac228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 08/05/2022] [Accepted: 09/03/2022] [Indexed: 02/07/2023] Open
Abstract
Mutations and aberrant gene expression during cellular differentiation lead to neurodevelopmental disorders, such as Prader-Willi syndrome (PWS), which results from the deletion of an imprinted locus on paternally inherited chromosome 15. We analyzed chromatin-associated RNA in human induced pluripotent cells (iPSCs) upon depletion of hybrid small nucleolar long non-coding RNAs (sno-lncRNAs) and 5' snoRNA capped and polyadenylated long non-coding RNAs (SPA-lncRNAs) transcribed from the locus deleted in PWS. We found that rapid ablation of these lncRNAs affects transcription of specific gene classes. Downregulated genes contribute to neurodevelopment and neuronal maintenance, while upregulated genes are predominantly involved in the negative regulation of cellular metabolism and apoptotic processes. Our data reveal the importance of SPA-lncRNAs and sno-lncRNAs in controlling gene expression in iPSCs and provide a platform for synthetic experimental approaches in PWS studies. We conclude that ncRNAs transcribed from the PWS locus are critical regulators of a transcriptional signature, which is important for neuronal differentiation and development.
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Affiliation(s)
- Monika Sledziowska
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Kinga Winczura
- School of Biological Sciences, University of Manchester, Michael Smith Building, Oxford Road, Manchester M13 9PT, UK
| | - Matt Jones
- School of Life Sciences, Gibbet Hill Campus, University of Warwick, Coventry CV4 7AL, UK
| | - Ruba Almaghrabi
- Institute for Cancer and Genomic Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Hannah Mischo
- School of Immunology & Microbial Sciences, King’s College London, London SE1 9RT, UK
| | - Daniel Hebenstreit
- School of Life Sciences, Gibbet Hill Campus, University of Warwick, Coventry CV4 7AL, UK
| | - Paloma Garcia
- Institute for Cancer and Genomic Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK,Birmingham Centre for Genome Biology, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Pawel Grzechnik
- To whom correspondence should be addressed at: School of Biological Sciences, University of Manchester, Michael Smith Building, Oxford Road, Manchester M13 9PT, UK.
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48
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Abstract
Transcription elongation by RNA polymerase II (Pol II) has emerged as a regulatory hub in gene expression. A key control point occurs during early transcription elongation when Pol II pauses in the promoter-proximal region at the majority of genes in mammalian cells and at a large set of genes in Drosophila. An increasing number of trans-acting factors have been linked to promoter-proximal pausing. Some factors help to establish the pause, whereas others are required for the release of Pol II into productive elongation. A dysfunction of this elongation control point leads to aberrant gene expression and can contribute to disease development. The BET bromodomain protein BRD4 has been implicated in elongation control. However, only recently direct BRD4-specific functions in Pol II transcription elongation have been uncovered. This mainly became possible with technological advances that allow selective and rapid ablation of BRD4 in cells along with the availability of approaches that capture the immediate consequences on nascent transcription. This review sheds light on the experimental breakthroughs that led to the emerging view of BRD4 as a general regulator of transcription elongation.
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Affiliation(s)
- Elisabeth Altendorfer
- Otto-Warburg-Laboratory, Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - Yelizaveta Mochalova
- Otto-Warburg-Laboratory, Max Planck Institute for Molecular Genetics, Berlin, Germany.,Department of Biology, Chemistry and Pharmacy, Freie Universität Berlin, Berlin, Germany
| | - Andreas Mayer
- Otto-Warburg-Laboratory, Max Planck Institute for Molecular Genetics, Berlin, Germany
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49
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Bozukova M, Nikopoulou C, Kleinenkuhnen N, Grbavac D, Goetsch K, Tessarz P. Aging is associated with increased chromatin accessibility and reduced polymerase pausing in liver. Mol Syst Biol 2022; 18:e11002. [PMID: 36082605 PMCID: PMC9459415 DOI: 10.15252/msb.202211002] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Revised: 08/09/2022] [Accepted: 08/15/2022] [Indexed: 11/29/2022] Open
Abstract
Regulation of gene expression is linked to the organization of the genome. With age, chromatin alterations occur on all levels of genome organization, accompanied by changes in the gene expression profile. However, little is known about the changes in the level of transcriptional regulation. Here, we used a multi‐omics approach and integrated ATAC‐, RNA‐ and NET‐seq to identify age‐related changes in the chromatin landscape of murine liver and to investigate how these are linked to transcriptional regulation. We provide the first systematic inventory of the connection between aging, chromatin accessibility, and transcriptional regulation in a whole tissue. Aging in murine liver is characterized by an increase in chromatin accessibility at promoter regions, but not in an increase in transcriptional output. Instead, aging is accompanied by a decrease in promoter‐proximal pausing of RNA polymerase II (Pol II), while initiation of transcription is not decreased as assessed by RNA polymerase mapping using CUT&RUN. Based on the data reported, we propose that these age‐related changes in transcriptional regulation are due to a reduced stability of the pausing complex.
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Affiliation(s)
- Mihaela Bozukova
- Max Planck Research Group 'Chromatin and Ageing', Max Planck Institute for Biology of Ageing, Cologne, Germany
| | - Chrysa Nikopoulou
- Max Planck Research Group 'Chromatin and Ageing', Max Planck Institute for Biology of Ageing, Cologne, Germany
| | - Niklas Kleinenkuhnen
- Max Planck Research Group 'Chromatin and Ageing', Max Planck Institute for Biology of Ageing, Cologne, Germany.,Faculty of Medicine, Institute of Medical Statistics and Computational Biology, University of Cologne, Cologne, Germany
| | - Dora Grbavac
- Max Planck Research Group 'Chromatin and Ageing', Max Planck Institute for Biology of Ageing, Cologne, Germany
| | - Katrin Goetsch
- Max Planck Research Group 'Chromatin and Ageing', Max Planck Institute for Biology of Ageing, Cologne, Germany
| | - Peter Tessarz
- Max Planck Research Group 'Chromatin and Ageing', Max Planck Institute for Biology of Ageing, Cologne, Germany.,Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
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50
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Terrone S, Valat J, Fontrodona N, Giraud G, Claude JB, Combe E, Lapendry A, Polvèche H, Ameur LB, Duvermy A, Modolo L, Bernard P, Mortreux F, Auboeuf D, Bourgeois C. RNA helicase-dependent gene looping impacts messenger RNA processing. Nucleic Acids Res 2022; 50:9226-9246. [PMID: 36039747 PMCID: PMC9458439 DOI: 10.1093/nar/gkac717] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 07/25/2022] [Accepted: 08/25/2022] [Indexed: 12/24/2022] Open
Abstract
DDX5 and DDX17 are DEAD-box RNA helicase paralogs which regulate several aspects of gene expression, especially transcription and splicing, through incompletely understood mechanisms. A transcriptome analysis of DDX5/DDX17-depleted human cells confirmed the large impact of these RNA helicases on splicing and revealed a widespread deregulation of 3' end processing. In silico analyses and experiments in cultured cells showed the binding and functional contribution of the genome organizing factor CTCF to chromatin sites at or near a subset of DDX5/DDX17-dependent exons that are characterized by a high GC content and a high density of RNA Polymerase II. We propose the existence of an RNA helicase-dependent relationship between CTCF and the dynamics of transcription across DNA and/or RNA structured regions, that contributes to the processing of internal and terminal exons. Moreover, local DDX5/DDX17-dependent chromatin loops spatially connect RNA helicase-regulated exons with their cognate promoter, and we provide the first direct evidence that de novo gene looping modifies alternative splicing and polyadenylation. Overall our findings uncover the impact of DDX5/DDX17-dependent chromatin folding on pre-messenger RNA processing.
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Affiliation(s)
| | | | - Nicolas Fontrodona
- Laboratoire de Biologie et Modelisation de la Cellule, Ecole Normale Superieure de Lyon, CNRS, UMR 5239, Inserm, U1293, Universite Claude Bernard Lyon 1, 46 allee d'Italie, F-69364 Lyon, France
| | | | - Jean-Baptiste Claude
- Laboratoire de Biologie et Modelisation de la Cellule, Ecole Normale Superieure de Lyon, CNRS, UMR 5239, Inserm, U1293, Universite Claude Bernard Lyon 1, 46 allee d'Italie, F-69364 Lyon, France
| | | | - Audrey Lapendry
- Laboratoire de Biologie et Modelisation de la Cellule, Ecole Normale Superieure de Lyon, CNRS, UMR 5239, Inserm, U1293, Universite Claude Bernard Lyon 1, 46 allee d'Italie, F-69364 Lyon, France
| | - Hélène Polvèche
- Laboratoire de Biologie et Modelisation de la Cellule, Ecole Normale Superieure de Lyon, CNRS, UMR 5239, Inserm, U1293, Universite Claude Bernard Lyon 1, 46 allee d'Italie, F-69364 Lyon, France,CECS/AFM, I-STEM, 28 rue Henri Desbruères, F-91100, Corbeil-Essonnes, France
| | - Lamya Ben Ameur
- Laboratoire de Biologie et Modelisation de la Cellule, Ecole Normale Superieure de Lyon, CNRS, UMR 5239, Inserm, U1293, Universite Claude Bernard Lyon 1, 46 allee d'Italie, F-69364 Lyon, France
| | - Arnaud Duvermy
- Laboratoire de Biologie et Modelisation de la Cellule, Ecole Normale Superieure de Lyon, CNRS, UMR 5239, Inserm, U1293, Universite Claude Bernard Lyon 1, 46 allee d'Italie, F-69364 Lyon, France
| | - Laurent Modolo
- Laboratoire de Biologie et Modelisation de la Cellule, Ecole Normale Superieure de Lyon, CNRS, UMR 5239, Inserm, U1293, Universite Claude Bernard Lyon 1, 46 allee d'Italie, F-69364 Lyon, France
| | - Pascal Bernard
- Laboratoire de Biologie et Modelisation de la Cellule, Ecole Normale Superieure de Lyon, CNRS, UMR 5239, Inserm, U1293, Universite Claude Bernard Lyon 1, 46 allee d'Italie, F-69364 Lyon, France
| | - Franck Mortreux
- Laboratoire de Biologie et Modelisation de la Cellule, Ecole Normale Superieure de Lyon, CNRS, UMR 5239, Inserm, U1293, Universite Claude Bernard Lyon 1, 46 allee d'Italie, F-69364 Lyon, France
| | - Didier Auboeuf
- Laboratoire de Biologie et Modelisation de la Cellule, Ecole Normale Superieure de Lyon, CNRS, UMR 5239, Inserm, U1293, Universite Claude Bernard Lyon 1, 46 allee d'Italie, F-69364 Lyon, France
| | - Cyril F Bourgeois
- To whom correspondence should be addressed. Tel: +33 47272 8663; Fax: +33 47272 8674;
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