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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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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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Williams J, Xu B, Putnam D, Thrasher A, Li C, Yang J, Chen X. MethylationToActivity: a deep-learning framework that reveals promoter activity landscapes from DNA methylomes in individual tumors. Genome Biol 2021; 22:24. [PMID: 33461601 PMCID: PMC7814737 DOI: 10.1186/s13059-020-02220-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Accepted: 12/06/2020] [Indexed: 12/12/2022] Open
Abstract
Although genome-wide DNA methylomes have demonstrated their clinical value as reliable biomarkers for tumor detection, subtyping, and classification, their direct biological impacts at the individual gene level remain elusive. Here we present MethylationToActivity (M2A), a machine learning framework that uses convolutional neural networks to infer promoter activities based on H3K4me3 and H3K27ac enrichment, from DNA methylation patterns for individual genes. Using publicly available datasets in real-world test scenarios, we demonstrate that M2A is highly accurate and robust in revealing promoter activity landscapes in various pediatric and adult cancers, including both solid and hematologic malignant neoplasms.
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Affiliation(s)
- Justin Williams
- Department of Computational Biology, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Mail Stop 1135, Memphis, TN, 38105, USA
| | - Beisi Xu
- Center for Applied Bioinformatics, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Daniel Putnam
- Department of Computational Biology, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Mail Stop 1135, Memphis, TN, 38105, USA
| | - Andrew Thrasher
- Department of Computational Biology, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Mail Stop 1135, Memphis, TN, 38105, USA
| | - Chunliang Li
- Department of Tumor Cell Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Jun Yang
- Department of Surgery, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Xiang Chen
- Department of Computational Biology, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Mail Stop 1135, Memphis, TN, 38105, USA.
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Nizovtseva EV, Todolli S, Olson WK, Studitsky VM. Towards quantitative analysis of gene regulation by enhancers. Epigenomics 2017; 9:1219-1231. [PMID: 28799793 DOI: 10.2217/epi-2017-0061] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Enhancers are regulatory DNA sequences that can activate transcription over large distances. Recent studies have revealed the widespread role of distant activation in eukaryotic gene regulation and in the development of various human diseases, including cancer. Here we review recent progress in the field, focusing on new experimental and computational approaches that quantify the role of chromatin structure and dynamics during enhancer-promoter interactions in vitro and in vivo.
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Affiliation(s)
- Ekaterina V Nizovtseva
- Cancer Epigenetics Program, Fox Chase Cancer Center, 333 Cottman Ave., Philadelphia, PA 19422, USA
| | - Stefjord Todolli
- Department of Chemistry & Chemical Biology, Center for Quantitative Biology, Rutgers, the State University of New Jersey, 610 Taylor Rd., Piscataway, NJ 08854, USA
| | - Wilma K Olson
- Department of Chemistry & Chemical Biology, Center for Quantitative Biology, Rutgers, the State University of New Jersey, 610 Taylor Rd., Piscataway, NJ 08854, USA
| | - Vasily M Studitsky
- Cancer Epigenetics Program, Fox Chase Cancer Center, 333 Cottman Ave., Philadelphia, PA 19422, USA.,Biology Faculty, Moscow State University, Moscow 119991, Russia.,Laboratory of Epigenetics, Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia
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Wyse B, Oshidari R, Rowlands H, Abbasi S, Yankulov K. RRM3 regulates epigenetic conversions in Saccharomyces cerevisiae in conjunction with Chromatin Assembly Factor I. Nucleus 2017; 7:405-14. [PMID: 27645054 DOI: 10.1080/19491034.2016.1212796] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Chromatin structures are transmitted to daughter cells through a complex system of nucleosome disassembly and re-assembly at the advancing replication forks. However, the role of replication pausing in the transmission and perturbation of chromatin structures has not been addressed. RRM3 encodes a DNA helicase, which facilitates replication at sites covered with non-histone protein complexes (tRNA genes, active gene promoters, telomeres) in Saccharomyces cerevisiae. In this report we show that the deletion of RRM3 reduces the frequency of epigenetic conversions in the subtelomeric regions of the chromosomes. This phenotype is strongly dependent on 2 histone chaperones, CAF-I and ASF1, which are involved in the reassembly of nucleosomes behind replication forks, but not on the histone chaperone HIR1. We also show that the deletion of RRM3 increases the spontaneous mutation rates in conjunction with CAF-I and ASF1, but not HIR1. Finally, we demonstrate that Rrm3p and CAF-I compete for the binding to the DNA replication clamp PCNA (Proliferating Cell Nuclear Antigen). We propose that the stalling of DNA replication predisposes to epigenetic conversions and that RRM3 and CAF-I play key roles in this process.
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Affiliation(s)
- Brandon Wyse
- a Department of Molecular and Cellular Biology , University of Guelph , Ontario , Canada
| | - Roxanne Oshidari
- a Department of Molecular and Cellular Biology , University of Guelph , Ontario , Canada
| | - Hollie Rowlands
- a Department of Molecular and Cellular Biology , University of Guelph , Ontario , Canada
| | - Sanna Abbasi
- a Department of Molecular and Cellular Biology , University of Guelph , Ontario , Canada
| | - Krassimir Yankulov
- a Department of Molecular and Cellular Biology , University of Guelph , Ontario , Canada
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Jeffery DCB, Wyse BA, Rehman MA, Brown GW, You Z, Oshidari R, Masai H, Yankulov KY. Analysis of epigenetic stability and conversions in Saccharomyces cerevisiae reveals a novel role of CAF-I in position-effect variegation. Nucleic Acids Res 2013; 41:8475-88. [PMID: 23863839 PMCID: PMC3794585 DOI: 10.1093/nar/gkt623] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Position-effect variegation (PEV) phenotypes are characterized by the robust multigenerational repression of a gene located at a certain locus (often called gene silencing) and occasional conversions to fully active state. Consequently, the active state then persists with occasional conversions to the repressed state. These effects are mediated by the establishment and maintenance of heterochromatin or euchromatin structures, respectively. In this study, we have addressed an important but often neglected aspect of PEV: the frequency of conversions at such loci. We have developed a model and have projected various PEV scenarios based on various rates of conversions. We have also enhanced two existing assays for gene silencing in Saccharomyces cerevisiae to measure the rate of switches from repressed to active state and vice versa. We tested the validity of our methodology in Δsir1 cells and in several mutants with defects in gene silencing. The assays have revealed that the histone chaperone Chromatin Assembly Factor I is involved in the control of epigenetic conversions. Together, our model and assays provide a comprehensive methodology for further investigation of epigenetic stability and position effects.
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Affiliation(s)
- Daniel C B Jeffery
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada, Laboratory for Foodborne Zoonoses, Public Health Agency of Canada, Guelph, Ontario, Canada and Department of Genome Medicine, Genome Dynamics Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
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Yankulov K. Dynamics and stability: epigenetic conversions in position effect variegation. Biochem Cell Biol 2013; 91:6-13. [DOI: 10.1139/bcb-2012-0048] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Position effect variegation (PEV) refers to quasi-stable patterns of gene expression that are observed at specific loci throughout the genomes of eukaryotes. The genes subjected to PEV can be completely silenced or fully active. Stochastic conversions between these 2 states are responsible for the variegated phenotypes. Positional variegation is used by human pathogens (Trypanosoma, Plasmodium, and Candida) to evade the immune system or adapt to the host environment. In the yeasts Saccharomyces cerevisiae and S accharomyces pombe, telomeric PEV aids the adaptation to a changing environment. In metazoans, similar epigenetic conversions are likely to accompany cell differentiation and the setting of tissue-specific gene expression programs. Surprisingly, we know very little about the mechanisms of epigenetic conversions. In this article, earlier models on the nature of PEV are revisited and recent advances on the dynamic nature of chromatin are reviewed. The normal dynamic histone turnover during transcription and DNA replication and its perturbation at transcription and replication pause sites are discussed. It is proposed that such perturbations play key roles in epigenetic conversions and in PEV.
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Affiliation(s)
- Krassimir Yankulov
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON N1G2W1, Canada
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Abstract
Enhancers are regulatory DNA sequences that activate transcription over long distances. Recent studies revealed a widespread role of distant activation in eukaryotic gene regulation and in development of various human diseases, including cancer. Genomic and gene-targeted studies of enhancer action revealed novel mechanisms of transcriptional activation over a distance. They include formation of stable, inactive DNA-protein complexes at the enhancer and target promoter before activation, facilitated distant communication by looping of the spacer chromatin-covered DNA, and promoter activation by mechanisms that are different from classic recruiting. These studies suggest the similarity between the looping mechanisms involved in enhancer action on DNA in bacteria and in chromatin of higher organisms.
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Dong X, Greven MC, Kundaje A, Djebali S, Brown JB, Cheng C, Gingeras TR, Gerstein M, Guigó R, Birney E, Weng Z. Modeling gene expression using chromatin features in various cellular contexts. Genome Biol 2012; 13:R53. [PMID: 22950368 PMCID: PMC3491397 DOI: 10.1186/gb-2012-13-9-r53] [Citation(s) in RCA: 175] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2012] [Revised: 06/13/2012] [Accepted: 06/19/2012] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND Previous work has demonstrated that chromatin feature levels correlate with gene expression. The ENCODE project enables us to further explore this relationship using an unprecedented volume of data. Expression levels from more than 100,000 promoters were measured using a variety of high-throughput techniques applied to RNA extracted by different protocols from different cellular compartments of several human cell lines. ENCODE also generated the genome-wide mapping of eleven histone marks, one histone variant, and DNase I hypersensitivity sites in seven cell lines. RESULTS We built a novel quantitative model to study the relationship between chromatin features and expression levels. Our study not only confirms that the general relationships found in previous studies hold across various cell lines, but also makes new suggestions about the relationship between chromatin features and gene expression levels. We found that expression status and expression levels can be predicted by different groups of chromatin features, both with high accuracy. We also found that expression levels measured by CAGE are better predicted than by RNA-PET or RNA-Seq, and different categories of chromatin features are the most predictive of expression for different RNA measurement methods. Additionally, PolyA+ RNA is overall more predictable than PolyA- RNA among different cell compartments, and PolyA+ cytosolic RNA measured with RNA-Seq is more predictable than PolyA+ nuclear RNA, while the opposite is true for PolyA- RNA. CONCLUSIONS Our study provides new insights into transcriptional regulation by analyzing chromatin features in different cellular contexts.
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Affiliation(s)
- Xianjun Dong
- Program in Bioinformatics and Integrative Biology, Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Melissa C Greven
- Program in Bioinformatics and Integrative Biology, Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Anshul Kundaje
- Department of Computer Science, Stanford University, 318 Campus Drive, Stanford, CA 94304, USA
| | - Sarah Djebali
- Centre for Genomic Regulation (CRG) and UPF, Dr. Aiguader, 88, 08003 Barcelona, Spain
| | - James B Brown
- Department of Statistics, University of California, Berkeley, 367 Evans Hall, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Chao Cheng
- Computational Biology and Bioinformatics Program, Yale University, 266 Whitney Ave, New Haven, CT 06511, USA
| | - Thomas R Gingeras
- Cold Spring Harbor Laboratory, Genome Center, Woodbury, New York 11797, USA
| | - Mark Gerstein
- Computational Biology and Bioinformatics Program, Yale University, 266 Whitney Ave, New Haven, CT 06511, USA
| | - Roderic Guigó
- Centre for Genomic Regulation (CRG) and UPF, Dr. Aiguader, 88, 08003 Barcelona, Spain
| | - Ewan Birney
- Vertebrate Genomics Group, European Bioinformatics Institute (EMBL-EBI), Wellcome Trust Genome Campus, Hinxton, Cambridgeshire, CB10 1SA, UK
| | - Zhiping Weng
- Program in Bioinformatics and Integrative Biology, Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01605, USA
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