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Cheng IH, Pi WC, Hsu CH, Guo Y, Lai JL, Wang GG, Chung BC, Roeder RG, Chen WY. TAF2, within the TFIID complex, regulates the expression of a subset of protein-coding genes. Cell Death Discov 2024; 10:244. [PMID: 38773077 PMCID: PMC11109217 DOI: 10.1038/s41420-024-02017-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Revised: 05/03/2024] [Accepted: 05/08/2024] [Indexed: 05/23/2024] Open
Abstract
TFIID, one of the general transcription factor (GTF), regulates transcriptional initiation of protein-coding genes through direct binding to promoter elements and subsequent recruitment of other GTFs and RNA polymerase II. Although generally required for most protein-coding genes, accumulated studies have also demonstrated promoter-specific functions for several TFIID subunits in gene activation. Here, we report that TBP-associated factor 2 (TAF2) specifically regulates TFIID binding to a small subset of protein-coding genes and is essential for cell growth of multiple cancer lines. Co-immunoprecipitation assays revealed that TAF2 may be sub-stoichiometrically associated with the TFIID complex, thus indicating a minor fraction of TAF2-containing TFIID in cells. Consistently, integrated genome-wide profiles show that TAF2 binds to and regulates only a small subset of protein-coding genes. Furthermore, through the use of an inducible TAF2 degradation system, our results reveal a reduction of TBP/TFIID binding to several ribosomal genes upon selective ablation of TAF2. In addition, depletion of TAF2, as well as the TAF2-regulated ribosomal protein genes RPL30 and RPL39, decreases ribosome assembly and global protein translation. Collectively, this study suggests that TAF2 within the TFIID complex is of functional importance for TBP/TFIID binding to and expression of a small subset of protein-coding genes, thus establishing a previously unappreciated promoter-selective function for TAF2.
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Affiliation(s)
- I-Hsin Cheng
- Institute of Biochemistry and Molecular Biology, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Wen-Chieh Pi
- Institute of Biochemistry and Molecular Biology, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Chung-Hao Hsu
- School of Medicine, College of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Yiran Guo
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC, 27710, USA
- Duke Cancer Institute, Durham, NC, 27710, USA
| | - Jun-Lin Lai
- Program in Molecular Medicine, National Yang Ming Chiao Tung University and Academia Sinica, Taipei, Taiwan
| | - Gang G Wang
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC, 27710, USA
- Duke Cancer Institute, Durham, NC, 27710, USA
| | - Bon-Chu Chung
- Insitute of Molecular Biology, Academia Sinica, Taipei, Taiwan
- Graduate Institute of Biomedical Sciences, Neuroscience and Brain Disease Center, China Medical University, Taichung, Taiwan
- National Laboratory Animal Center, National Applied Research Laboratories, Taipei, Taiwan
| | - Robert G Roeder
- Laboratory of Biochemistry and Molecular Biology, The Rockefeller University, New York, NY, 10065, USA
| | - Wei-Yi Chen
- Institute of Biochemistry and Molecular Biology, National Yang Ming Chiao Tung University, Taipei, Taiwan.
- Program in Molecular Medicine, National Yang Ming Chiao Tung University and Academia Sinica, Taipei, Taiwan.
- Cancer and Immunology Research Center, National Yang Ming Chiao Tung University, Taipei, Taiwan.
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2
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Khandibharad S, Singh S. Single-cell ATAC sequencing identifies sleepy macrophages during reciprocity of cytokines in L. major infection. Microbiol Spectr 2024; 12:e0347823. [PMID: 38299832 PMCID: PMC10913457 DOI: 10.1128/spectrum.03478-23] [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: 09/25/2023] [Accepted: 12/31/2023] [Indexed: 02/02/2024] Open
Abstract
The hallmark characteristic of macrophages lies in their inherent plasticity, allowing them to adapt to dynamic microenvironments. Leishmania strategically modulates the phenotypic plasticity of macrophages, creating a favorable environment for intracellular survival and persistent infection through regulatory cytokine such as interleukin (IL)-10. Nevertheless, these effector cells can counteract infection by modulating crucial cytokines like IL-12 and key components involved in its production. Using sophisticated tool of single-cell assay for transposase accessible chromatin (ATAC) sequencing, we systematically examined the regulatory axis of IL-10 and IL-12 in a time-dependent manner during Leishmania major infection in macrophages Our analysis revealed the cellular heterogeneity post-infection with the regulators of IL-10 and IL-12, unveiling a reciprocal relationship between these cytokines. Notably, our significant findings highlighted the presence of sleepy macrophages and their pivotal role in mediating reciprocity between IL-10 and IL-12. To summarize, the roles of cytokine expression, transcription factors, cell cycle, and epigenetics of host cell machinery were vital in identification of sleepy macrophages, which is a transient state where transcription factors controlled the epigenetic remodeling and expression of genes involved in pro-inflammatory cytokine expression and recruitment of immune cells.IMPORTANCELeishmaniasis is an endemic affecting 99 countries and territories globally, as outlined in the 2022 World Health Organization report. The disease's severity is compounded by compromised host immune systems, emphasizing the pivotal role of the interplay between parasite and host immune factors in disease regulation. In instances of cutaneous leishmaniasis induced by L. major, macrophages function as sentinel cells. Our findings indicate that the plasticity and phenotype of macrophages can be modulated to express a cytokine profile involving IL-10 and IL-12, mediated by the regulation of transcription factors and their target genes post-L. major infection in macrophages. Employing sophisticated methodologies such as single-cell ATAC sequencing and computational genomics, we have identified a distinctive subset of macrophages termed "sleepy macrophages." These macrophages exhibit downregulated housekeeping genes while expressing a unique set of variable features. This data set constitutes a valuable resource for comprehending the intricate host-parasite interplay during L. major infection.
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Affiliation(s)
- Shweta Khandibharad
- Systems Medicine Lab, National Centre for Cell Science, SP Pune University Campus, Pune, India
| | - Shailza Singh
- Systems Medicine Lab, National Centre for Cell Science, SP Pune University Campus, Pune, India
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3
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Luna-Arias JP, Castro-Muñozledo F. Participation of the TBP-associated factors (TAFs) in cell differentiation. J Cell Physiol 2024; 239:e31167. [PMID: 38126142 DOI: 10.1002/jcp.31167] [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: 09/18/2023] [Revised: 11/04/2023] [Accepted: 11/27/2023] [Indexed: 12/23/2023]
Abstract
The understanding of the mechanisms that regulate gene expression to establish differentiation programs and determine cell lineages, is one of the major challenges in Developmental Biology. Besides the participation of tissue-specific transcription factors and epigenetic processes, the role of general transcription factors has been ignored. Only in recent years, there have been scarce studies that address this issue. Here, we review the studies on the biological activity of some TATA-box binding protein (TBP)-associated factors (TAFs) during the proliferation of stem/progenitor cells and their involvement in cell differentiation. Particularly, the accumulated evidence suggests that TAF4, TAF4b, TAF7L, TAF8, TAF9, and TAF10, among others, participate in nervous system development, adipogenesis, myogenesis, and epidermal differentiation; while TAF1, TAF7, TAF15 may be involved in the regulation of stem cell proliferative abilities and cell cycle progression. On the other hand, evidence suggests that TBP variants such as TBPL1 and TBPL2 might be regulating some developmental processes such as germ cell maturation and differentiation, myogenesis, or ventral specification during development. Our analysis shows that it is necessary to study in greater depth the biological function of these factors and its participation in the assembly of specific transcription complexes that contribute to the differential gene expression that gives rise to the great diversity of cell types existing in an organism. The understanding of TAFs' regulation might lead to the development of new therapies for patients which suffer from mutations, alterations, and dysregulation of these essential elements of the transcriptional machinery.
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Affiliation(s)
- Juan Pedro Luna-Arias
- Departamento de Biología Celular, Centro de Investigación y de Estudios Avanzados del IPN, México City, Mexico
| | - Federico Castro-Muñozledo
- Departamento de Biología Celular, Centro de Investigación y de Estudios Avanzados del IPN, México City, Mexico
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4
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Liu X, Chen M, Qu X, Liu W, Dou Y, Liu Q, Shi D, Jiang M, Li H. Cis-Regulatory Elements in Mammals. Int J Mol Sci 2023; 25:343. [PMID: 38203513 PMCID: PMC10779164 DOI: 10.3390/ijms25010343] [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: 11/29/2023] [Revised: 12/21/2023] [Accepted: 12/23/2023] [Indexed: 01/12/2024] Open
Abstract
In cis-regulatory elements, enhancers and promoters with complex molecular interactions are used to coordinate gene transcription through physical proximity and chemical modifications. These processes subsequently influence the phenotypic characteristics of an organism. An in-depth exploration of enhancers and promoters can substantially enhance our understanding of gene regulatory networks, shedding new light on mammalian development, evolution and disease pathways. In this review, we provide a comprehensive overview of the intrinsic structural attributes, detection methodologies as well as the operational mechanisms of enhancers and promoters, coupled with the relevant novel and innovative investigative techniques used to explore their actions. We further elucidated the state-of-the-art research on the roles of enhancers and promoters in the realms of mammalian development, evolution and disease, and we conclude with forward-looking insights into prospective research avenues.
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Affiliation(s)
| | | | | | | | | | | | | | - Mingsheng Jiang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangxi Key Laboratory of Animal Breeding, Disease Control and Prevention, College of Animal Science and Technology, Guangxi University, Nanning 530005, China
| | - Hui Li
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangxi Key Laboratory of Animal Breeding, Disease Control and Prevention, College of Animal Science and Technology, Guangxi University, Nanning 530005, China
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5
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Hisler V, Bardot P, Detilleux D, Stierle M, Sanchez EG, Richard C, Arab LH, Ehrhard C, Morlet B, Hadzhiev Y, Jung M, Gras SL, Négroni L, Müller F, Tora L, Vincent SD. RNA polymerase II transcription with partially assembled TFIID complexes. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.27.567046. [PMID: 38076793 PMCID: PMC10705246 DOI: 10.1101/2023.11.27.567046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/24/2023]
Abstract
The recognition of core promoter sequences by the general transcription factor TFIID is the first step in the process of RNA polymerase II (Pol II) transcription initiation. Metazoan holo-TFIID is composed of the TATA binding protein (TBP) and of 13 TBP associated factors (TAFs). Inducible Taf7 knock out (KO) results in the formation of a Taf7-less TFIID complex, while Taf10 KO leads to serious defects within the TFIID assembly pathway. Either TAF7 or TAF10 depletions correlate with the detected TAF occupancy changes at promoters, and with the distinct phenotype severities observed in mouse embryonic stem cells or mouse embryos. Surprisingly however, under either Taf7 or Taf10 deletion conditions, TBP is still associated to the chromatin, and no major changes are observed in nascent Pol II transcription. Thus, partially assembled TFIID complexes can sustain Pol II transcription initiation, but cannot replace holo-TFIID over several cell divisions and/or development.
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Affiliation(s)
- Vincent Hisler
- Université de Strasbourg, IGBMC UMR 7104- UMR-S 1258, F-67400 Illkirch, France
- CNRS, UMR 7104, F-67400 Illkirch, France
- Inserm, UMR-S 1258, F-67400 Illkirch, France
- IGBMC, Institut de Génétique et de Biologie Moléculaire et Cellulaire, F-67400 Illkirch, France
| | - Paul Bardot
- Université de Strasbourg, IGBMC UMR 7104- UMR-S 1258, F-67400 Illkirch, France
- CNRS, UMR 7104, F-67400 Illkirch, France
- Inserm, UMR-S 1258, F-67400 Illkirch, France
- IGBMC, Institut de Génétique et de Biologie Moléculaire et Cellulaire, F-67400 Illkirch, France
| | - Dylane Detilleux
- Université de Strasbourg, IGBMC UMR 7104- UMR-S 1258, F-67400 Illkirch, France
- CNRS, UMR 7104, F-67400 Illkirch, France
- Inserm, UMR-S 1258, F-67400 Illkirch, France
- IGBMC, Institut de Génétique et de Biologie Moléculaire et Cellulaire, F-67400 Illkirch, France
| | - Matthieu Stierle
- Université de Strasbourg, IGBMC UMR 7104- UMR-S 1258, F-67400 Illkirch, France
- CNRS, UMR 7104, F-67400 Illkirch, France
- Inserm, UMR-S 1258, F-67400 Illkirch, France
- IGBMC, Institut de Génétique et de Biologie Moléculaire et Cellulaire, F-67400 Illkirch, France
| | - Emmanuel Garcia Sanchez
- Université de Strasbourg, IGBMC UMR 7104- UMR-S 1258, F-67400 Illkirch, France
- CNRS, UMR 7104, F-67400 Illkirch, France
- Inserm, UMR-S 1258, F-67400 Illkirch, France
- IGBMC, Institut de Génétique et de Biologie Moléculaire et Cellulaire, F-67400 Illkirch, France
| | - Claire Richard
- Université de Strasbourg, IGBMC UMR 7104- UMR-S 1258, F-67400 Illkirch, France
- CNRS, UMR 7104, F-67400 Illkirch, France
- Inserm, UMR-S 1258, F-67400 Illkirch, France
- IGBMC, Institut de Génétique et de Biologie Moléculaire et Cellulaire, F-67400 Illkirch, France
| | - Lynda Hadj Arab
- Université de Strasbourg, IGBMC UMR 7104- UMR-S 1258, F-67400 Illkirch, France
- CNRS, UMR 7104, F-67400 Illkirch, France
- Inserm, UMR-S 1258, F-67400 Illkirch, France
- IGBMC, Institut de Génétique et de Biologie Moléculaire et Cellulaire, F-67400 Illkirch, France
| | - Cynthia Ehrhard
- Université de Strasbourg, IGBMC UMR 7104- UMR-S 1258, F-67400 Illkirch, France
- CNRS, UMR 7104, F-67400 Illkirch, France
- Inserm, UMR-S 1258, F-67400 Illkirch, France
- IGBMC, Institut de Génétique et de Biologie Moléculaire et Cellulaire, F-67400 Illkirch, France
| | - Bastien Morlet
- Université de Strasbourg, IGBMC UMR 7104- UMR-S 1258, F-67400 Illkirch, France
- CNRS, UMR 7104, F-67400 Illkirch, France
- Inserm, UMR-S 1258, F-67400 Illkirch, France
- IGBMC, Institut de Génétique et de Biologie Moléculaire et Cellulaire, F-67400 Illkirch, France
- Proteomics platform
| | - Yavor Hadzhiev
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, B152TT, Birmingham, UK
| | - Matthieu Jung
- Université de Strasbourg, IGBMC UMR 7104- UMR-S 1258, F-67400 Illkirch, France
- CNRS, UMR 7104, F-67400 Illkirch, France
- Inserm, UMR-S 1258, F-67400 Illkirch, France
- IGBMC, Institut de Génétique et de Biologie Moléculaire et Cellulaire, F-67400 Illkirch, France
- GenomEast
| | - Stéphanie Le Gras
- Université de Strasbourg, IGBMC UMR 7104- UMR-S 1258, F-67400 Illkirch, France
- CNRS, UMR 7104, F-67400 Illkirch, France
- Inserm, UMR-S 1258, F-67400 Illkirch, France
- IGBMC, Institut de Génétique et de Biologie Moléculaire et Cellulaire, F-67400 Illkirch, France
- GenomEast
| | - Luc Négroni
- Université de Strasbourg, IGBMC UMR 7104- UMR-S 1258, F-67400 Illkirch, France
- CNRS, UMR 7104, F-67400 Illkirch, France
- Inserm, UMR-S 1258, F-67400 Illkirch, France
- IGBMC, Institut de Génétique et de Biologie Moléculaire et Cellulaire, F-67400 Illkirch, France
- Proteomics platform
| | - Ferenc Müller
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, B152TT, Birmingham, UK
| | - László Tora
- Université de Strasbourg, IGBMC UMR 7104- UMR-S 1258, F-67400 Illkirch, France
- CNRS, UMR 7104, F-67400 Illkirch, France
- Inserm, UMR-S 1258, F-67400 Illkirch, France
- IGBMC, Institut de Génétique et de Biologie Moléculaire et Cellulaire, F-67400 Illkirch, France
| | - Stéphane D. Vincent
- Université de Strasbourg, IGBMC UMR 7104- UMR-S 1258, F-67400 Illkirch, France
- CNRS, UMR 7104, F-67400 Illkirch, France
- Inserm, UMR-S 1258, F-67400 Illkirch, France
- IGBMC, Institut de Génétique et de Biologie Moléculaire et Cellulaire, F-67400 Illkirch, France
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6
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Kaplow IM, Lawler AJ, Schäffer DE, Srinivasan C, Sestili HH, Wirthlin ME, Phan BN, Prasad K, Brown AR, Zhang X, Foley K, Genereux DP, Karlsson EK, Lindblad-Toh K, Meyer WK, Pfenning AR, Andrews G, Armstrong JC, Bianchi M, Birren BW, Bredemeyer KR, Breit AM, Christmas MJ, Clawson H, Damas J, Di Palma F, Diekhans M, Dong MX, Eizirik E, Fan K, Fanter C, Foley NM, Forsberg-Nilsson K, Garcia CJ, Gatesy J, Gazal S, Genereux DP, Goodman L, Grimshaw J, Halsey MK, Harris AJ, Hickey G, Hiller M, Hindle AG, Hubley RM, Hughes GM, Johnson J, Juan D, Kaplow IM, Karlsson EK, Keough KC, Kirilenko B, Koepfli KP, Korstian JM, Kowalczyk A, Kozyrev SV, Lawler AJ, Lawless C, Lehmann T, Levesque DL, Lewin HA, Li X, Lind A, Lindblad-Toh K, Mackay-Smith A, Marinescu VD, Marques-Bonet T, Mason VC, Meadows JRS, Meyer WK, Moore JE, Moreira LR, Moreno-Santillan DD, Morrill KM, Muntané G, Murphy WJ, Navarro A, Nweeia M, Ortmann S, Osmanski A, Paten B, Paulat NS, Pfenning AR, Phan BN, Pollard KS, Pratt HE, Ray DA, Reilly SK, Rosen JR, Ruf I, Ryan L, Ryder OA, Sabeti PC, Schäffer DE, Serres A, Shapiro B, Smit AFA, Springer M, Srinivasan C, Steiner C, Storer JM, Sullivan KAM, Sullivan PF, Sundström E, Supple MA, Swofford R, Talbot JE, Teeling E, Turner-Maier J, Valenzuela A, Wagner F, Wallerman O, Wang C, Wang J, Weng Z, Wilder AP, Wirthlin ME, Xue JR, Zhang X. Relating enhancer genetic variation across mammals to complex phenotypes using machine learning. Science 2023; 380:eabm7993. [PMID: 37104615 DOI: 10.1126/science.abm7993] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Abstract
Protein-coding differences between species often fail to explain phenotypic diversity, suggesting the involvement of genomic elements that regulate gene expression such as enhancers. Identifying associations between enhancers and phenotypes is challenging because enhancer activity can be tissue-dependent and functionally conserved despite low sequence conservation. We developed the Tissue-Aware Conservation Inference Toolkit (TACIT) to associate candidate enhancers with species' phenotypes using predictions from machine learning models trained on specific tissues. Applying TACIT to associate motor cortex and parvalbumin-positive interneuron enhancers with neurological phenotypes revealed dozens of enhancer-phenotype associations, including brain size-associated enhancers that interact with genes implicated in microcephaly or macrocephaly. TACIT provides a foundation for identifying enhancers associated with the evolution of any convergently evolved phenotype in any large group of species with aligned genomes.
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Affiliation(s)
- Irene M Kaplow
- Department of Computational Biology, Carnegie Mellon University, Pittsburgh, PA, USA
- Neuroscience Institute, Carnegie Mellon University, Pittsburgh, PA, USA
| | - Alyssa J Lawler
- Neuroscience Institute, Carnegie Mellon University, Pittsburgh, PA, USA
- Department of Biology, Carnegie Mellon University, Pittsburgh, PA, USA
| | - Daniel E Schäffer
- Department of Computational Biology, Carnegie Mellon University, Pittsburgh, PA, USA
| | - Chaitanya Srinivasan
- Department of Computational Biology, Carnegie Mellon University, Pittsburgh, PA, USA
| | - Heather H Sestili
- Department of Computational Biology, Carnegie Mellon University, Pittsburgh, PA, USA
| | - Morgan E Wirthlin
- Department of Computational Biology, Carnegie Mellon University, Pittsburgh, PA, USA
- Neuroscience Institute, Carnegie Mellon University, Pittsburgh, PA, USA
| | - BaDoi N Phan
- Department of Computational Biology, Carnegie Mellon University, Pittsburgh, PA, USA
- Neuroscience Institute, Carnegie Mellon University, Pittsburgh, PA, USA
- Medical Scientist Training Program, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Kavya Prasad
- Department of Computational Biology, Carnegie Mellon University, Pittsburgh, PA, USA
| | - Ashley R Brown
- Department of Computational Biology, Carnegie Mellon University, Pittsburgh, PA, USA
| | - Xiaomeng Zhang
- Department of Computational Biology, Carnegie Mellon University, Pittsburgh, PA, USA
| | - Kathleen Foley
- Department of Biological Sciences, Lehigh University, Bethlehem, PA, USA
| | - Diane P Genereux
- Broad Institute, Cambridge, MA, USA
- Program in Bioinformatics and Integrative Biology, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Elinor K Karlsson
- Broad Institute, Cambridge, MA, USA
- Program in Bioinformatics and Integrative Biology, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Kerstin Lindblad-Toh
- Broad Institute, Cambridge, MA, USA
- Science for Life Laboratory, Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Wynn K Meyer
- Department of Biological Sciences, Lehigh University, Bethlehem, PA, USA
| | - Andreas R Pfenning
- Department of Computational Biology, Carnegie Mellon University, Pittsburgh, PA, USA
- Neuroscience Institute, Carnegie Mellon University, Pittsburgh, PA, USA
- Department of Biology, Carnegie Mellon University, Pittsburgh, PA, USA
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7
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Säisä-Borreill S, Davidson G, Kleiber T, Thevenot A, Martin E, Mondot S, Blottière H, Helleux A, Mengus G, Plateroti M, Duluc I, Davidson I, Freund JN. General transcription factor TAF4 antagonizes epigenetic silencing by Polycomb to maintain intestine stem cell functions. Cell Death Differ 2023; 30:839-853. [PMID: 36639541 PMCID: PMC9984434 DOI: 10.1038/s41418-022-01109-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 12/15/2022] [Accepted: 12/21/2022] [Indexed: 01/15/2023] Open
Abstract
Taf4 (TATA-box binding protein-associated factor 4) is a subunit of the general transcription factor TFIID, a component of the RNA polymerase II pre-initiation complex that interacts with tissue-specific transcription factors to regulate gene expression. Properly regulated gene expression is particularly important in the intestinal epithelium that is constantly renewed from stem cells. Tissue-specific inactivation of Taf4 in murine intestinal epithelium during embryogenesis compromised gut morphogenesis and the emergence of adult-type stem cells. In adults, Taf4 loss impacted the stem cell compartment and associated Paneth cells in the stem cell niche, epithelial turnover and differentiation of mature cells, thus exacerbating the response to inflammatory challenge. Taf4 inactivation ex vivo in enteroids prevented budding formation and maintenance and caused broad chromatin remodeling and a strong reduction in the numbers of stem and progenitor cells with a concomitant increase in an undifferentiated cell population that displayed high activity of the Ezh2 and Suz12 components of Polycomb Repressive Complex 2 (PRC2). Treatment of Taf4-mutant enteroids with a specific Ezh2 inhibitor restored buddings, cell proliferation and the stem/progenitor compartment. Taf4 loss also led to increased PRC2 activity in cells of adult crypts associated with modification of the immune/inflammatory microenvironment that potentiated Apc-driven tumorigenesis. Our results reveal a novel function of Taf4 in antagonizing PRC2-mediated repression of the stem cell gene expression program to assure normal development, homeostasis, and immune-microenvironment of the intestinal epithelium.
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Affiliation(s)
- Susanna Säisä-Borreill
- University of Strasbourg, Inserm, UMR-S1113/IRFAC, FHU ARRIMAGE, FMTS, 67200, Strasbourg, France
| | - Guillaume Davidson
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Department of Functional Genomics and Cancer, CNRS/Inserm/University of Strasbourg, 1 Rue Laurent Fries, 67404, Illkirch Cédex, France
| | - Thomas Kleiber
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Department of Functional Genomics and Cancer, CNRS/Inserm/University of Strasbourg, 1 Rue Laurent Fries, 67404, Illkirch Cédex, France
- Orphazyme, Ole Maaloes 3, 2200, Copenhagen, Denmark
| | - Andréa Thevenot
- University of Strasbourg, Inserm, UMR-S1113/IRFAC, FHU ARRIMAGE, FMTS, 67200, Strasbourg, France
| | - Elisabeth Martin
- University of Strasbourg, Inserm, UMR-S1113/IRFAC, FHU ARRIMAGE, FMTS, 67200, Strasbourg, France
| | - Stanislas Mondot
- University Paris-Saclay, INRAE, AgroParisTech, Micalis Institute, 78350, Jouy-en-Josas, France
| | - Hervé Blottière
- University Paris-Saclay, INRAE, AgroParisTech, Micalis Institute, 78350, Jouy-en-Josas, France
| | - Alexandra Helleux
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Department of Functional Genomics and Cancer, CNRS/Inserm/University of Strasbourg, 1 Rue Laurent Fries, 67404, Illkirch Cédex, France
| | - Gabrielle Mengus
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Department of Functional Genomics and Cancer, CNRS/Inserm/University of Strasbourg, 1 Rue Laurent Fries, 67404, Illkirch Cédex, France
| | - Michelina Plateroti
- University of Strasbourg, Inserm, UMR-S1113/IRFAC, FHU ARRIMAGE, FMTS, 67200, Strasbourg, France
| | - Isabelle Duluc
- University of Strasbourg, Inserm, UMR-S1113/IRFAC, FHU ARRIMAGE, FMTS, 67200, Strasbourg, France
| | - Irwin Davidson
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Department of Functional Genomics and Cancer, CNRS/Inserm/University of Strasbourg, 1 Rue Laurent Fries, 67404, Illkirch Cédex, France
| | - Jean-Noel Freund
- University of Strasbourg, Inserm, UMR-S1113/IRFAC, FHU ARRIMAGE, FMTS, 67200, Strasbourg, France.
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8
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Evaluating Phenotypic and Transcriptomic Responses Induced by Low-Level VOCs in Zebrafish: Benzene as an Example. TOXICS 2022; 10:toxics10070351. [PMID: 35878256 PMCID: PMC9324908 DOI: 10.3390/toxics10070351] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/15/2022] [Revised: 06/23/2022] [Accepted: 06/24/2022] [Indexed: 11/16/2022]
Abstract
Urban environments are plagued by complex mixtures of anthropogenic volatile organic compounds (VOCs), such as mixtures of benzene, toluene, ethylene, and xylene (BTEX). Sources of BTEX that drive human exposure include vehicle exhaust, industrial emissions, off-gassing of building material, as well as oil spillage and leakage. Among the BTEX mixture, benzene is the most volatile compound and has been linked to numerous adverse health outcomes. However, few studies have focused on the effects of low-level benzene on exposure during early development, which is a susceptible window when hematological, immune, metabolic, and detoxification systems are immature. In this study, we used zebrafish to conduct a VOC exposure model and evaluated phenotypic and transcriptomic responses following 0.1 and 1 ppm benzene exposure during the first five days of embryogenesis (n = 740 per treatment). The benzene body burden was 2 mg/kg in 1 ppm-exposed larval zebrafish pools and under the detection limit in 0.1 ppm-exposed fish. No observable phenotypic changes were found in both larvae except for significant skeletal deformities in 0.1 ppm-exposed fish (p = 0.01) compared with unexposed fish. Based on transcriptomic responses, 1 ppm benzene dysregulated genes that were implicated with the development of hematological system, and the regulation of oxidative stress response, fatty acid metabolism, immune system, and inflammatory response, including apob, nfkbiaa, serpinf1, foxa1, cyp2k6, and cyp2n13 from the cytochrome P450 gene family. Key genes including pik3c2b, pltp, and chia.2 were differentially expressed in both 1 and 0.1 ppm exposures. However, fewer transcriptomic changes were induced by 0.1 ppm compared with 1 ppm. Future studies are needed to determine if these transcriptomic responses during embryogenesis have long-term consequences at levels equal to or lower than 1 ppm.
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9
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El-Saafin F, Bergamasco MI, Chen Y, May RE, Esakky P, Hediyeh-Zadeh S, Dixon M, Wilcox S, Davis MJ, Strasser A, Smyth GK, Thomas T, Voss AK. Loss of TAF8 causes TFIID dysfunction and p53-mediated apoptotic neuronal cell death. Cell Death Differ 2022; 29:1013-1027. [PMID: 35361962 PMCID: PMC9091217 DOI: 10.1038/s41418-022-00982-5] [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: 03/26/2021] [Revised: 03/08/2022] [Accepted: 03/10/2022] [Indexed: 11/08/2022] Open
Abstract
Mutations in genes encoding general transcription factors cause neurological disorders. Despite clinical prominence, the consequences of defects in the basal transcription machinery during brain development are unclear. We found that loss of the TATA-box binding protein-associated factor TAF8, a component of the general transcription factor TFIID, in the developing central nervous system affected the expression of many, but notably not all genes. Taf8 deletion caused apoptosis, unexpectedly restricted to forebrain regions. Nuclear levels of the transcription factor p53 were elevated in the absence of TAF8, as were the mRNAs of the pro-apoptotic p53 target genes Noxa, Puma and Bax. The cell death in Taf8 forebrain regions was completely rescued by additional loss of p53, but Taf8 and p53 brains failed to initiate a neuronal expression program. Taf8 deletion caused aberrant transcription of promoter regions and splicing anomalies. We propose that TAF8 supports the directionality of transcription and co-transcriptional splicing, and that failure of these processes causes p53-induced apoptosis of neuronal cells in the developing mouse embryo.
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Affiliation(s)
- Farrah El-Saafin
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, 3052, Australia
- Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia
| | - Maria I Bergamasco
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, 3052, Australia
- Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia
| | - Yunshun Chen
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, 3052, Australia
- Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia
| | - Rose E May
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, 3052, Australia
| | - Prabagaran Esakky
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, 3052, Australia
- Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia
| | - Soroor Hediyeh-Zadeh
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, 3052, Australia
- Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia
| | - Mathew Dixon
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, 3052, Australia
- Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia
| | - Stephen Wilcox
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, 3052, Australia
| | - Melissa J Davis
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, 3052, Australia
- Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia
- Department of Clinical Pathology, University of Melbourne, Parkville, VIC, Australia
- The University of Queensland Diamantina Institute, Woolloongabba, QLD, Australia
| | - Andreas Strasser
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, 3052, Australia
- Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia
| | - Gordon K Smyth
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, 3052, Australia
- School of Mathematics and Statistics, University of Melbourne, Parkville, VIC, Australia
| | - Tim Thomas
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, 3052, Australia.
- Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia.
| | - Anne K Voss
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, 3052, Australia.
- Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia.
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10
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Kleiber T, Davidson G, Mengus G, Martianov I, Davidson I. Single cell transcriptomics reveal trans-differentiation of pancreatic beta cells following inactivation of the TFIID subunit Taf4. Cell Death Dis 2021; 12:790. [PMID: 34385420 PMCID: PMC8361202 DOI: 10.1038/s41419-021-04067-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 07/22/2021] [Accepted: 07/26/2021] [Indexed: 12/28/2022]
Abstract
Regulation of gene expression involves a complex and dynamic dialogue between transcription factors, chromatin remodelling and modification complexes and the basal transcription machinery. To address the function of the Taf4 subunit of general transcription factor TFIID in the regulation of insulin signalling, it was inactivated in adult murine pancreatic beta cells. Taf4 inactivation impacted the expression of critical genes involved in beta-cell function leading to increased glycaemia, lowered plasma insulin levels and defective glucose-stimulated insulin secretion. One week after Taf4-loss, single-cell RNA-seq revealed cells with mixed beta cell, alpha and/or delta cell identities as well as a beta cell population trans-differentiating into alpha-like cells. Computational analysis of single-cell RNA-seq defines how known critical beta cell and alpha cell determinants may act in combination with additional transcription factors and the NuRF chromatin remodelling complex to promote beta cell trans-differentiation.
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Affiliation(s)
- Thomas Kleiber
- Institut de Génétique et de Biologie Moléculaire et Cellulaire. BP 163, 67404 Illkirch Cedex, C.U, Strasbourg, France.,Centre National de la Recherche Scientifique, UMR7104, Illkirch, France.,Institut National de la Santé et de la Recherche Médicale, U1258, Illkirch, France.,Université de Strasbourg, Illkirch, France.,Orphazyme, Ole Malloes Vej 3, 2200, Copenhagen, Danmark
| | - Guillaume Davidson
- Institut de Génétique et de Biologie Moléculaire et Cellulaire. BP 163, 67404 Illkirch Cedex, C.U, Strasbourg, France.,Centre National de la Recherche Scientifique, UMR7104, Illkirch, France.,Institut National de la Santé et de la Recherche Médicale, U1258, Illkirch, France.,Université de Strasbourg, Illkirch, France
| | - Gabrielle Mengus
- Institut de Génétique et de Biologie Moléculaire et Cellulaire. BP 163, 67404 Illkirch Cedex, C.U, Strasbourg, France.,Centre National de la Recherche Scientifique, UMR7104, Illkirch, France.,Institut National de la Santé et de la Recherche Médicale, U1258, Illkirch, France.,Université de Strasbourg, Illkirch, France
| | - Igor Martianov
- Institut de Génétique et de Biologie Moléculaire et Cellulaire. BP 163, 67404 Illkirch Cedex, C.U, Strasbourg, France.,Centre National de la Recherche Scientifique, UMR7104, Illkirch, France.,Institut National de la Santé et de la Recherche Médicale, U1258, Illkirch, France.,Université de Strasbourg, Illkirch, France
| | - Irwin Davidson
- Institut de Génétique et de Biologie Moléculaire et Cellulaire. BP 163, 67404 Illkirch Cedex, C.U, Strasbourg, France. .,Centre National de la Recherche Scientifique, UMR7104, Illkirch, France. .,Institut National de la Santé et de la Recherche Médicale, U1258, Illkirch, France. .,Université de Strasbourg, Illkirch, France. .,Equipe Labélisée Ligue National contre le Cancer, Alsace, France.
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11
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Control of Cell Identity by the Nuclear Receptor HNF4 in Organ Pathophysiology. Cells 2020; 9:cells9102185. [PMID: 32998360 PMCID: PMC7600215 DOI: 10.3390/cells9102185] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 09/25/2020] [Accepted: 09/26/2020] [Indexed: 12/14/2022] Open
Abstract
Hepatocyte Nuclear Factor 4 (HNF4) is a transcription factor (TF) belonging to the nuclear receptor family whose expression and activities are restricted to a limited number of organs including the liver and gastrointestinal tract. In this review, we present robust evidence pointing to HNF4 as a master regulator of cellular differentiation during development and a safekeeper of acquired cell identity in adult organs. Importantly, we discuss that transient loss of HNF4 may represent a protective mechanism upon acute organ injury, while prolonged impairment of HNF4 activities could contribute to organ dysfunction. In this context, we describe in detail mechanisms involved in the pathophysiological control of cell identity by HNF4, including how HNF4 works as part of cell-specific TF networks and how its expression/activities are disrupted in injured organs.
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12
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Epigenetic therapies in acute myeloid leukemia: where to from here? Blood 2020; 134:1891-1901. [PMID: 31697822 DOI: 10.1182/blood.2019003262] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Accepted: 10/06/2019] [Indexed: 12/11/2022] Open
Abstract
A hallmark of acute myeloid leukemia (AML) is epigenetic dysregulation, which is initiated by recurrent translocations and/or mutations in transcription factors and chromatin regulators. This manifests as a block in myeloid differentiation and an increase in malignant self-renewal. These common features of AML have led to widespread optimism that epigenetic therapies would dramatically change the natural history of this disease. Although preclinical studies with these drugs fueled this optimism, results from early clinical trials have offered a more sobering message. Here, we provide an overview of epigenetic therapies that are currently approved by therapeutic regulatory authorities across the world and those undergoing early-phase clinical trials. We also discuss the conceptual and molecular factors that may explain some of the disparity between the bench and bedside, as well as emerging avenues for combining the current generation of epigenetic therapies with other classes of agents and the development of novel epigenetic therapies. With further research and development of this exciting class of drugs, we may finally be able to dramatically improve outcomes for patients afflicted with this aggressive and often incurable malignancy.
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13
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Torok MS, Pray-Grant MG, Grant BM, Josephs ME, Grant PA. The Novel ReNu Region of TAF12 Regulates Gcn5 Nucleosomal Acetylation. JOURNAL OF MOLECULAR GENETICS (ISLEWORTH, LONDON, ENGLAND) 2019; 2:https://researchopenworld.com/wp-content/uploads/2019/07/JMG-2019-105-Patrick-Grant-USA.pdf. [PMID: 32832935 PMCID: PMC7437354] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The post-translational acetylation of the histone components of chromatin mediates numerous DNA-templated events, including transcriptional activation, DNA repair, and genomic replication. The conserved SAGA (Spt-Ada-Gcn5 Acetyltranferase) and SLIK (SAGA-Like) Histone Acetyltransferase (HAT) complexes are required for transcriptional activation of a subset of yeast genes and contain multiple subunits including the histone fold-containing TBP- Associated Factors (TAFs): 6, 9, 10, and 12. These TAFs are also components of the TFIID complex and are consequently involved in most RNA polymerase II-transcription in yeast. Here we identify a novel conserved region of TAF12, termed ReNu, outside of its histone fold, which is required for SAGA and SLIK-directed nucleosomal acetylation. We demonstrate that this region is not required for chromatin association, but show that this region plays an important role for histone H3 acetylation at specific SAGA and SLIK-regulated promoters. Our data suggests that the ReNu region of TAF12 regulates Gcn5 acetylation of specific substrates within the SAGA super-family of HAT complexes.
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Affiliation(s)
| | | | | | | | - Patrick A. Grant
- Corresponding author: Patrick A. Grant, University of Virginia School of Medicine, Box 800733, Charlottesville, VA 22908, USA; Tel: (434) 243-5766; Fax: (434) 924-5069;
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14
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Huck I, Gunewardena S, Espanol-Suner R, Willenbring H, Apte U. Hepatocyte Nuclear Factor 4 Alpha Activation Is Essential for Termination of Liver Regeneration in Mice. Hepatology 2019; 70:666-681. [PMID: 30520062 PMCID: PMC6551324 DOI: 10.1002/hep.30405] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Accepted: 11/23/2018] [Indexed: 12/14/2022]
Abstract
Hepatocyte nuclear factor 4 alpha (HNF4α) is critical for hepatic differentiation. Recent studies have highlighted its role in inhibition of hepatocyte proliferation and tumor suppression. However, the role of HNF4α in liver regeneration (LR) is not known. We hypothesized that hepatocytes modulate HNF4α activity when navigating between differentiated and proliferative states during LR. Western blotting analysis revealed a rapid decline in nuclear and cytoplasmic HNF4α protein levels, accompanied with decreased target gene expression, within 1 hour after two-thirds partial hepatectomy (post-PH) in C57BL/6J mice. HNF4α protein expression did not recover to pre-PH levels until day 3. Hepatocyte-specific deletion of HNF4α (HNF4α-KO [knockout]) in mice resulted in 100% mortality post-PH, despite increased proliferative marker expression throughout regeneration. Sustained loss of HNF4α target gene expression throughout regeneration indicated that HNF4α-KO mice were unable to compensate for loss of HNF4α transcriptional activity. Deletion of HNF4α resulted in sustained proliferation accompanied by c-Myc and cyclin D1 overexpression and a complete deficiency of hepatocyte function after PH. Interestingly, overexpression of degradation-resistant HNF4α in hepatocytes delayed, but did not prevent, initiation of regeneration after PH. Finally, adeno-associated virus serotype 8 (AAV8)-mediated reexpression of HNF4α in hepatocytes of HNF4α-KO mice post-PH restored HNF4α protein levels, induced target gene expression, and improved survival of HNF4α-KO mice post-PH. Conclusion: In conclusion, these data indicate that HNF4α reexpression following initial decrease is critical for hepatocytes to exit from cell cycle and resume function during the termination phase of LR. These results indicate the role of HNF4α in LR and have implications for therapy of liver failure.
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Affiliation(s)
- Ian Huck
- Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, KS
| | - Sumedha Gunewardena
- Department of Biostatistics University of Kansas Medical Center, Kansas City, KS
| | | | - Holger Willenbring
- Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research,Liver Center, Division of Transplantation, University of California San Francisco, San Francisco, CA,Department of Surgery, Division of Transplantation, University of California San Francisco, San Francisco, CA
| | - Udayan Apte
- Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, KS
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15
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Grindheim JM, Nicetto D, Donahue G, Zaret KS. Polycomb Repressive Complex 2 Proteins EZH1 and EZH2 Regulate Timing of Postnatal Hepatocyte Maturation and Fibrosis by Repressing Genes With Euchromatic Promoters in Mice. Gastroenterology 2019; 156:1834-1848. [PMID: 30689973 PMCID: PMC6599454 DOI: 10.1053/j.gastro.2019.01.041] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Revised: 01/02/2019] [Accepted: 01/16/2019] [Indexed: 02/06/2023]
Abstract
BACKGROUND & AIMS Little is known about mechanisms that underlie postnatal hepatocyte maturation and fibrosis at the chromatin level. We investigated the transcription of genes involved in maturation and fibrosis in postnatal hepatocytes of mice, focusing on the chromatin compaction the roles of the Polycomb repressive complex 2 histone methyltransferases EZH1 and EZH2. METHODS Hepatocytes were isolated from mixed background C57BL/6J-C3H mice, as well as mice with liver-specific disruption of Ezh1 and/or Ezh2, at postnatal day 14 and 2 months after birth. Liver tissues were collected and analyzed by RNA sequencing, H3K27me3 chromatin immunoprecipitation sequencing, and sonication-resistant heterochromatin sequencing (a method to map heterochromatin and euchromatin). Liver damage was characterized by histologic analysis. RESULTS We found more than 3000 genes differentially expressed in hepatocytes during liver maturation from postnatal day 14 to month 2 after birth. Disruption of Ezh1 and Ezh2 in livers caused perinatal hepatocytes to differentiate prematurely and to express genes at postnatal day 14 that would normally be induced by month 2 and differentiate prematurely. Loss of Ezh1 and Ezh2 also resulted in liver fibrosis. Genes with H3K27me3-postive and H3K4me3-positive euchromatic promoters were prematurely induced in hepatocytes with loss of Ezh1 and Ezh2-these genes included those that regulate hepatocyte maturation, fibrosis, and genes not specifically associated with the liver lineage. CONCLUSIONS The Polycomb repressive complex 2 proteins EZH1 and EZH2 regulate genes that control hepatocyte maturation and fibrogenesis and genes not specifically associated with the liver lineage by acting at euchromatic promoter regions. EZH1 and EZH2 thereby promote liver homeostasis and prevent liver damage. Strategies to manipulate Polycomb proteins might be used to improve hepatocyte derivation protocols or developed for treatment of patients with liver fibrosis.
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Affiliation(s)
- Jessica Mae Grindheim
- Institute for Regenerative Medicine, University of Pennsylvania, Smilow Center for Translational Research, 3400 Civic Center Blvd, Bldg. 421, Philadelphia, PA 19104-5157, USA.,Penn Epigenetics Institute, University of Pennsylvania, Smilow Center for Translational Research, 3400 Civic Center Blvd, Bldg. 421, Philadelphia, PA 19104-5157, USA.,Dept. Cell and Developmental Biology, University of Pennsylvania, Smilow Center for Translational Research, 3400 Civic Center Blvd, Bldg. 421, Philadelphia, PA 19104-5157, USA.,Dept. of Cancer Biology, University of Pennsylvania, Smilow Center for Translational Research, 3400 Civic Center Blvd, Bldg. 421, Philadelphia, PA 19104-5157, USA.,Perelman School of Medicine, University of Pennsylvania, Smilow Center for Translational Research, 3400 Civic Center Blvd, Bldg. 421, Philadelphia, PA 19104-5157, USA
| | - Dario Nicetto
- Institute for Regenerative Medicine, University of Pennsylvania, Smilow Center for Translational Research, 3400 Civic Center Blvd, Bldg. 421, Philadelphia, PA 19104-5157, USA.,Penn Epigenetics Institute, University of Pennsylvania, Smilow Center for Translational Research, 3400 Civic Center Blvd, Bldg. 421, Philadelphia, PA 19104-5157, USA.,Dept. Cell and Developmental Biology, University of Pennsylvania, Smilow Center for Translational Research, 3400 Civic Center Blvd, Bldg. 421, Philadelphia, PA 19104-5157, USA
| | - Greg Donahue
- Institute for Regenerative Medicine, University of Pennsylvania, Smilow Center for Translational Research, 3400 Civic Center Blvd, Bldg. 421, Philadelphia, PA 19104-5157, USA.,Penn Epigenetics Institute, University of Pennsylvania, Smilow Center for Translational Research, 3400 Civic Center Blvd, Bldg. 421, Philadelphia, PA 19104-5157, USA.,Dept. Cell and Developmental Biology, University of Pennsylvania, Smilow Center for Translational Research, 3400 Civic Center Blvd, Bldg. 421, Philadelphia, PA 19104-5157, USA.,Perelman School of Medicine, University of Pennsylvania, Smilow Center for Translational Research, 3400 Civic Center Blvd, Bldg. 421, Philadelphia, PA 19104-5157, USA
| | - Kenneth S Zaret
- Institute for Regenerative Medicine, University of Pennsylvania, Smilow Center for Translational Research, Philadelphia, Pennsylvania; Penn Epigenetics Institute, University of Pennsylvania, Smilow Center for Translational Research, Philadelphia, Pennsylvania; Department of Cell and Developmental Biology, University of Pennsylvania, Smilow Center for Translational Research, Philadelphia, Pennsylvania; Perelman School of Medicine, University of Pennsylvania, Smilow Center for Translational Research, Philadelphia, Pennsylvania.
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16
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Xu Y, Milazzo JP, Somerville TDD, Tarumoto Y, Huang YH, Ostrander EL, Wilkinson JE, Challen GA, Vakoc CR. A TFIID-SAGA Perturbation that Targets MYB and Suppresses Acute Myeloid Leukemia. Cancer Cell 2018; 33:13-28.e8. [PMID: 29316427 PMCID: PMC5764110 DOI: 10.1016/j.ccell.2017.12.002] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Revised: 09/22/2017] [Accepted: 12/05/2017] [Indexed: 01/08/2023]
Abstract
Targeting of general coactivators is an emerging strategy to interfere with oncogenic transcription factors (TFs). However, coactivator perturbations often lead to pleiotropic effects by influencing numerous TFs. Here we identify TAF12, a subunit of TFIID and SAGA coactivator complexes, as a selective requirement for acute myeloid leukemia (AML) progression. We trace this dependency to a direct interaction between the TAF12/TAF4 histone-fold heterodimer and the transactivation domain of MYB, a TF with established roles in leukemogenesis. Ectopic expression of the TAF4 histone-fold fragment can efficiently squelch TAF12 in cells, suppress MYB, and regress AML in mice. Our study reveals a strategy for potent MYB inhibition in AML and highlights how an oncogenic TF can be selectively neutralized by targeting a general coactivator complex.
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Affiliation(s)
- Yali Xu
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA; Molecular and Cellular Biology Program, Stony Brook University, New York, NY 11794, USA
| | - Joseph P Milazzo
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | | | - Yusuke Tarumoto
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | - Yu-Han Huang
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | - Elizabeth L Ostrander
- Division of Oncology, Department of Internal Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - John E Wilkinson
- ULAM/Department of Pathology, University of Michigan School of Medicine, Ann Arbor, MI 48109, USA
| | - Grant A Challen
- Division of Oncology, Department of Internal Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
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17
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Joshi S, Ueberschlag-Pitiot V, Metzger D, Davidson I. Improved Protocol for Chromatin Immunoprecipitation from Mouse Skeletal Muscle. J Vis Exp 2017. [PMID: 29155791 DOI: 10.3791/56504] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
We describe an efficient and reproducible protocol for the preparation of chromatin from adult mouse skeletal muscle, a physically resistant tissue with a high content of structural proteins. Dissected limb muscles from adult mice are physically disrupted by mechanical homogenisation, or a combination of mincing and douncing, in a hypotonic buffer before formaldehyde fixation of the cell lysate. The fixed nuclei are purified by further cycles of mechanical homogenisation or douncing and sequential filtrations to remove cell debris. The purified nuclei can be sonicated immediately or at a later stage after freezing. The chromatin can be efficiently sonicated and is suitable for chromatin immunoprecipitation experiments, as illustrated by the profiles obtained for transcription factors, RNA polymerase II, and covalent histone modifications. The binding events detected using chromatin prepared by this protocol are predominantly those taking place in the muscle fiber nuclei despite the presence of chromatin from other fiber-associated satellite and endothelial cells. This protocol is therefore adapted to study gene regulation in the adult mouse skeletal muscle.
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Affiliation(s)
- Shilpy Joshi
- Department of Functional Genomics and Cancer, Institut de Génétique et de Biologie Moléculaire et Cellulaire
| | - Vanessa Ueberschlag-Pitiot
- Department of Functional Genomics and Cancer, Institut de Génétique et de Biologie Moléculaire et Cellulaire
| | - Daniel Metzger
- Department of Functional Genomics and Cancer, Institut de Génétique et de Biologie Moléculaire et Cellulaire;
| | - Irwin Davidson
- Department of Functional Genomics and Cancer, Institut de Génétique et de Biologie Moléculaire et Cellulaire;
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18
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Simcox J, Geoghegan G, Maschek JA, Bensard CL, Pasquali M, Miao R, Lee S, Jiang L, Huck I, Kershaw EE, Donato AJ, Apte U, Longo N, Rutter J, Schreiber R, Zechner R, Cox J, Villanueva CJ. Global Analysis of Plasma Lipids Identifies Liver-Derived Acylcarnitines as a Fuel Source for Brown Fat Thermogenesis. Cell Metab 2017; 26:509-522.e6. [PMID: 28877455 PMCID: PMC5658052 DOI: 10.1016/j.cmet.2017.08.006] [Citation(s) in RCA: 162] [Impact Index Per Article: 23.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Revised: 04/27/2017] [Accepted: 08/08/2017] [Indexed: 12/30/2022]
Abstract
Cold-induced thermogenesis is an energy-demanding process that protects endotherms against a reduction in ambient temperature. Using non-targeted liquid chromatography-mass spectrometry-based lipidomics, we identified elevated levels of plasma acylcarnitines in response to the cold. We found that the liver undergoes a metabolic switch to provide fuel for brown fat thermogenesis by producing acylcarnitines. Cold stimulates white adipocytes to release free fatty acids that activate the nuclear receptor HNF4α, which is required for acylcarnitine production in the liver and adaptive thermogenesis. Once in circulation, acylcarnitines are transported to brown adipose tissue, while uptake into white adipose tissue and liver is blocked. Finally, a bolus of L-carnitine or palmitoylcarnitine rescues the cold sensitivity seen with aging. Our data highlight an elegant mechanism whereby white adipose tissue provides long-chain fatty acids for hepatic carnitilation to generate plasma acylcarnitines as a fuel source for peripheral tissues in mice.
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Affiliation(s)
- Judith Simcox
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
| | - Gisela Geoghegan
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
| | - John Alan Maschek
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
| | - Claire L Bensard
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT 84112, USA; Howard Hughes Medical Institute, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
| | - Marzia Pasquali
- Department of Pathology, University of Utah School of Medicine, Salt Lake City, UT 84112, USA; Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
| | - Ren Miao
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
| | - Sanghoon Lee
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
| | - Lei Jiang
- Children's Research Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Ian Huck
- Department of Pharmacology, Toxicology, and Therapeutics, University of Kansas Medical Center, Kansas City, KS 66160, USA
| | - Erin E Kershaw
- Department of Medicine, Division of Endocrinology and Metabolism, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Anthony J Donato
- Department of Exercise and Sport Science, Geriatric Research, Education, and Clinical Center, Veteran's Affairs Medical Center, Salt Lake City, UT 84112, USA
| | - Udayan Apte
- Department of Pharmacology, Toxicology, and Therapeutics, University of Kansas Medical Center, Kansas City, KS 66160, USA
| | - Nicola Longo
- Department of Pathology, University of Utah School of Medicine, Salt Lake City, UT 84112, USA; Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
| | - Jared Rutter
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT 84112, USA; Howard Hughes Medical Institute, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
| | - Renate Schreiber
- Institute of Molecular Biosciences, University of Graz, Heinrichstrasse 31, 8010 Graz, Austria
| | - Rudolf Zechner
- Institute of Molecular Biosciences, University of Graz, Heinrichstrasse 31, 8010 Graz, Austria
| | - James Cox
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
| | - Claudio J Villanueva
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT 84112, USA.
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Zabidi MA, Stark A. Regulatory Enhancer-Core-Promoter Communication via Transcription Factors and Cofactors. Trends Genet 2016; 32:801-814. [PMID: 27816209 DOI: 10.1016/j.tig.2016.10.003] [Citation(s) in RCA: 129] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Revised: 10/08/2016] [Accepted: 10/10/2016] [Indexed: 01/20/2023]
Abstract
Gene expression is regulated by genomic enhancers that recruit transcription factors and cofactors to activate transcription from target core promoters. Over the past years, thousands of enhancers and core promoters in animal genomes have been annotated, and we have learned much about the domain structure in which regulatory genomes are organized in animals. Enhancer-core-promoter targeting occurs at several levels, including regulatory domains, DNA accessibility, and sequence-encoded core-promoter specificities that are likely mediated by different regulatory proteins. We review here current knowledge about enhancer-core-promoter targeting, regulatory communication between enhancers and core promoters, and the protein factors involved. We conclude with an outlook on open questions that we find particularly interesting and that will likely lead to additional insights in the upcoming years.
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Affiliation(s)
- Muhammad A Zabidi
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Dr. Bohr-Gasse 7, 1030 Vienna, Austria
| | - Alexander Stark
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Dr. Bohr-Gasse 7, 1030 Vienna, Austria.
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20
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CLIP-GENE: a web service of the condition specific context-laid integrative analysis for gene prioritization in mouse TF knockout experiments. Biol Direct 2016; 11:57. [PMID: 27776539 PMCID: PMC5078909 DOI: 10.1186/s13062-016-0158-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Accepted: 10/10/2016] [Indexed: 02/06/2023] Open
Abstract
MOTIVATION Transcriptome data from the gene knockout experiment in mouse is widely used to investigate functions of genes and relationship to phenotypes. When a gene is knocked out, it is important to identify which genes are affected by the knockout gene. Existing methods, including differentially expressed gene (DEG) methods, can be used for the analysis. However, existing methods require cutoff values to select candidate genes, which can produce either too many false positives or false negatives. This hurdle can be addressed either by improving the accuracy of gene selection or by providing a method to rank candidate genes effectively, or both. Prioritization of candidate genes should consider the goals or context of the knockout experiment. As of now, there are no tools designed for both selecting and prioritizing genes from the mouse knockout data. Hence, the necessity of a new tool arises. RESULTS In this study, we present CLIP-GENE, a web service that selects gene markers by utilizing differentially expressed genes, mouse transcription factor (TF) network, and single nucleotide variant information. Then, protein-protein interaction network and literature information are utilized to find genes that are relevant to the phenotypic differences. One of the novel features is to allow researchers to specify their contexts or hypotheses in a set of keywords to rank genes according to the contexts that the user specify. We believe that CLIP-GENE will be useful in characterizing functions of TFs in mouse experiments. AVAILABILITY http://epigenomics.snu.ac.kr/CLIP-GENE REVIEWERS: This article was reviewed by Dr. Lee and Dr. Pongor.
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21
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Palierne G, Fabre A, Solinhac R, Le Péron C, Avner S, Lenfant F, Fontaine C, Salbert G, Flouriot G, Arnal JF, Métivier R. Changes in Gene Expression and Estrogen Receptor Cistrome in Mouse Liver Upon Acute E2 Treatment. Mol Endocrinol 2016; 30:709-32. [PMID: 27164166 DOI: 10.1210/me.2015-1311] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Transcriptional regulation by the estrogen receptor-α (ER) has been investigated mainly in breast cancer cell lines, but estrogens such as 17β-estradiol (E2) exert numerous extrareproductive effects, particularly in the liver, where E2 exhibits both protective metabolic and deleterious thrombotic actions. To analyze the direct and early transcriptional effects of estrogens in the liver, we determined the E2-sensitive transcriptome and ER cistrome in mice after acute administration of E2 or placebo. These analyses revealed the early induction of genes involved in lipid metabolism, which fits with the crucial role of ER in the prevention of liver steatosis. Characterization of the chromatin state of ER binding sites (BSs) in mice expressing or not ER demonstrated that ER is not required per se for the establishment and/or maintenance of chromatin modifications at the majority of its BSs. This is presumably a consequence of a strong overlap between ER and hepatocyte nuclear factor 4α BSs. In contrast, 40% of the BSs of the pioneer factor forkhead box protein a (Foxa2) were dependent upon ER expression, and ER expression also affected the distribution of nucleosomes harboring dimethylated lysine 4 of Histone H3 around Foxa2 BSs. We finally show that, in addition to a network of liver-specific transcription factors including CCAAT/enhancer-binding protein and hepatocyte nuclear factor 4α, ER might be required for proper Foxa2 function in this tissue.
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Affiliation(s)
- Gaëlle Palierne
- Equipe Spatio-Temporal Regulation of Transcription in Eukaryotes (SP@RTE) (G.P., C.L.P., S.A., G.S., R.M.), Unité Mixte de Recherche 6290 Centre National de la Recherche Scientifique (Institut de Genétique et Développement de Rennes), Université de Rennes 1, Campus de Beaulieu, and Equipe Transcription, Environment and Cancer (TREC) (G.F.), Inserm U1085-Institut de Recherche en Santé, Environnement et Travail, Rennes 35042 Cedex, France; and Equipe 9 "Estrogen Receptor: In Vivo Dissection and Modulation" (A.F., R.S., F.L., C.F., J.-F.A.), Inserm Unité 1048 (Institut des Maladies Métaboliques et Cardiovasculaires), Toulouse 31432 Cedex 4, France
| | - Aurélie Fabre
- Equipe Spatio-Temporal Regulation of Transcription in Eukaryotes (SP@RTE) (G.P., C.L.P., S.A., G.S., R.M.), Unité Mixte de Recherche 6290 Centre National de la Recherche Scientifique (Institut de Genétique et Développement de Rennes), Université de Rennes 1, Campus de Beaulieu, and Equipe Transcription, Environment and Cancer (TREC) (G.F.), Inserm U1085-Institut de Recherche en Santé, Environnement et Travail, Rennes 35042 Cedex, France; and Equipe 9 "Estrogen Receptor: In Vivo Dissection and Modulation" (A.F., R.S., F.L., C.F., J.-F.A.), Inserm Unité 1048 (Institut des Maladies Métaboliques et Cardiovasculaires), Toulouse 31432 Cedex 4, France
| | - Romain Solinhac
- Equipe Spatio-Temporal Regulation of Transcription in Eukaryotes (SP@RTE) (G.P., C.L.P., S.A., G.S., R.M.), Unité Mixte de Recherche 6290 Centre National de la Recherche Scientifique (Institut de Genétique et Développement de Rennes), Université de Rennes 1, Campus de Beaulieu, and Equipe Transcription, Environment and Cancer (TREC) (G.F.), Inserm U1085-Institut de Recherche en Santé, Environnement et Travail, Rennes 35042 Cedex, France; and Equipe 9 "Estrogen Receptor: In Vivo Dissection and Modulation" (A.F., R.S., F.L., C.F., J.-F.A.), Inserm Unité 1048 (Institut des Maladies Métaboliques et Cardiovasculaires), Toulouse 31432 Cedex 4, France
| | - Christine Le Péron
- Equipe Spatio-Temporal Regulation of Transcription in Eukaryotes (SP@RTE) (G.P., C.L.P., S.A., G.S., R.M.), Unité Mixte de Recherche 6290 Centre National de la Recherche Scientifique (Institut de Genétique et Développement de Rennes), Université de Rennes 1, Campus de Beaulieu, and Equipe Transcription, Environment and Cancer (TREC) (G.F.), Inserm U1085-Institut de Recherche en Santé, Environnement et Travail, Rennes 35042 Cedex, France; and Equipe 9 "Estrogen Receptor: In Vivo Dissection and Modulation" (A.F., R.S., F.L., C.F., J.-F.A.), Inserm Unité 1048 (Institut des Maladies Métaboliques et Cardiovasculaires), Toulouse 31432 Cedex 4, France
| | - Stéphane Avner
- Equipe Spatio-Temporal Regulation of Transcription in Eukaryotes (SP@RTE) (G.P., C.L.P., S.A., G.S., R.M.), Unité Mixte de Recherche 6290 Centre National de la Recherche Scientifique (Institut de Genétique et Développement de Rennes), Université de Rennes 1, Campus de Beaulieu, and Equipe Transcription, Environment and Cancer (TREC) (G.F.), Inserm U1085-Institut de Recherche en Santé, Environnement et Travail, Rennes 35042 Cedex, France; and Equipe 9 "Estrogen Receptor: In Vivo Dissection and Modulation" (A.F., R.S., F.L., C.F., J.-F.A.), Inserm Unité 1048 (Institut des Maladies Métaboliques et Cardiovasculaires), Toulouse 31432 Cedex 4, France
| | - Françoise Lenfant
- Equipe Spatio-Temporal Regulation of Transcription in Eukaryotes (SP@RTE) (G.P., C.L.P., S.A., G.S., R.M.), Unité Mixte de Recherche 6290 Centre National de la Recherche Scientifique (Institut de Genétique et Développement de Rennes), Université de Rennes 1, Campus de Beaulieu, and Equipe Transcription, Environment and Cancer (TREC) (G.F.), Inserm U1085-Institut de Recherche en Santé, Environnement et Travail, Rennes 35042 Cedex, France; and Equipe 9 "Estrogen Receptor: In Vivo Dissection and Modulation" (A.F., R.S., F.L., C.F., J.-F.A.), Inserm Unité 1048 (Institut des Maladies Métaboliques et Cardiovasculaires), Toulouse 31432 Cedex 4, France
| | - Coralie Fontaine
- Equipe Spatio-Temporal Regulation of Transcription in Eukaryotes (SP@RTE) (G.P., C.L.P., S.A., G.S., R.M.), Unité Mixte de Recherche 6290 Centre National de la Recherche Scientifique (Institut de Genétique et Développement de Rennes), Université de Rennes 1, Campus de Beaulieu, and Equipe Transcription, Environment and Cancer (TREC) (G.F.), Inserm U1085-Institut de Recherche en Santé, Environnement et Travail, Rennes 35042 Cedex, France; and Equipe 9 "Estrogen Receptor: In Vivo Dissection and Modulation" (A.F., R.S., F.L., C.F., J.-F.A.), Inserm Unité 1048 (Institut des Maladies Métaboliques et Cardiovasculaires), Toulouse 31432 Cedex 4, France
| | - Gilles Salbert
- Equipe Spatio-Temporal Regulation of Transcription in Eukaryotes (SP@RTE) (G.P., C.L.P., S.A., G.S., R.M.), Unité Mixte de Recherche 6290 Centre National de la Recherche Scientifique (Institut de Genétique et Développement de Rennes), Université de Rennes 1, Campus de Beaulieu, and Equipe Transcription, Environment and Cancer (TREC) (G.F.), Inserm U1085-Institut de Recherche en Santé, Environnement et Travail, Rennes 35042 Cedex, France; and Equipe 9 "Estrogen Receptor: In Vivo Dissection and Modulation" (A.F., R.S., F.L., C.F., J.-F.A.), Inserm Unité 1048 (Institut des Maladies Métaboliques et Cardiovasculaires), Toulouse 31432 Cedex 4, France
| | - Gilles Flouriot
- Equipe Spatio-Temporal Regulation of Transcription in Eukaryotes (SP@RTE) (G.P., C.L.P., S.A., G.S., R.M.), Unité Mixte de Recherche 6290 Centre National de la Recherche Scientifique (Institut de Genétique et Développement de Rennes), Université de Rennes 1, Campus de Beaulieu, and Equipe Transcription, Environment and Cancer (TREC) (G.F.), Inserm U1085-Institut de Recherche en Santé, Environnement et Travail, Rennes 35042 Cedex, France; and Equipe 9 "Estrogen Receptor: In Vivo Dissection and Modulation" (A.F., R.S., F.L., C.F., J.-F.A.), Inserm Unité 1048 (Institut des Maladies Métaboliques et Cardiovasculaires), Toulouse 31432 Cedex 4, France
| | - Jean-François Arnal
- Equipe Spatio-Temporal Regulation of Transcription in Eukaryotes (SP@RTE) (G.P., C.L.P., S.A., G.S., R.M.), Unité Mixte de Recherche 6290 Centre National de la Recherche Scientifique (Institut de Genétique et Développement de Rennes), Université de Rennes 1, Campus de Beaulieu, and Equipe Transcription, Environment and Cancer (TREC) (G.F.), Inserm U1085-Institut de Recherche en Santé, Environnement et Travail, Rennes 35042 Cedex, France; and Equipe 9 "Estrogen Receptor: In Vivo Dissection and Modulation" (A.F., R.S., F.L., C.F., J.-F.A.), Inserm Unité 1048 (Institut des Maladies Métaboliques et Cardiovasculaires), Toulouse 31432 Cedex 4, France
| | - Raphaël Métivier
- Equipe Spatio-Temporal Regulation of Transcription in Eukaryotes (SP@RTE) (G.P., C.L.P., S.A., G.S., R.M.), Unité Mixte de Recherche 6290 Centre National de la Recherche Scientifique (Institut de Genétique et Développement de Rennes), Université de Rennes 1, Campus de Beaulieu, and Equipe Transcription, Environment and Cancer (TREC) (G.F.), Inserm U1085-Institut de Recherche en Santé, Environnement et Travail, Rennes 35042 Cedex, France; and Equipe 9 "Estrogen Receptor: In Vivo Dissection and Modulation" (A.F., R.S., F.L., C.F., J.-F.A.), Inserm Unité 1048 (Institut des Maladies Métaboliques et Cardiovasculaires), Toulouse 31432 Cedex 4, France
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22
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Langer D, Martianov I, Alpern D, Rhinn M, Keime C, Dollé P, Mengus G, Davidson I. Essential role of the TFIID subunit TAF4 in murine embryogenesis and embryonic stem cell differentiation. Nat Commun 2016; 7:11063. [PMID: 27026076 PMCID: PMC4820908 DOI: 10.1038/ncomms11063] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Accepted: 02/17/2016] [Indexed: 12/15/2022] Open
Abstract
TAF4 (TATA-binding protein-associated factor 4) and its paralogue TAF4b are components of the TFIID core module. We inactivated the murine Taf4a gene to address Taf4 function during embryogenesis. Here we show that Taf4a−/− embryos survive until E9.5 where primary germ layers and many embryonic structures are identified showing Taf4 is dispensable for their specification. In contrast, Taf4 is required for correct patterning of the trunk and anterior structures, ventral morphogenesis and proper heart positioning. Overlapping expression of Taf4a and Taf4b during embryogenesis suggests their redundancy at early stages. In agreement with this, Taf4a−/− embryonic stem cells (ESCs) are viable and comprise Taf4b-containing TFIID. Nevertheless, Taf4a−/− ESCs do not complete differentiation into glutamatergic neurons and cardiomyocytes in vitro due to impaired preinitiation complex formation at the promoters of critical differentiation genes. We define an essential role of a core TFIID TAF in differentiation events during mammalian embryogenesis. The role of TFIID core module TAFs (TATA-binding protein-associated factors) in embryogenesis is unknown. Here, the authors show that Taf4 is essential at mid-gestation and for complete neuronal differentiation of embryonic stem cells, but that Taf4a and Taf4b are redundant at early embryonic stages.
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Affiliation(s)
- Diana Langer
- Department of Functional Genomics and Cancer, Institut de Génétique et de Biologie Moléculaire et Cellulaire, CNRS/INSERM/ULP, 1 Rue Laurent Fries, 67404 Illkirch, France
| | - Igor Martianov
- Department of Functional Genomics and Cancer, Institut de Génétique et de Biologie Moléculaire et Cellulaire, CNRS/INSERM/ULP, 1 Rue Laurent Fries, 67404 Illkirch, France
| | - Daniel Alpern
- Department of Functional Genomics and Cancer, Institut de Génétique et de Biologie Moléculaire et Cellulaire, CNRS/INSERM/ULP, 1 Rue Laurent Fries, 67404 Illkirch, France.,L'École polytechnique fédérale de Lausanne, Route Cantonale, 1015 Lausanne, Switzerland
| | - Muriel Rhinn
- Department of Development and Stem Cells, Institut de Génétique et de Biologie Moléculaire et Cellulaire, CNRS/INSERM/ULP, 1 Rue Laurent Fries, 67404 Illkirch, France
| | - Céline Keime
- Department of Functional Genomics and Cancer, Institut de Génétique et de Biologie Moléculaire et Cellulaire, CNRS/INSERM/ULP, 1 Rue Laurent Fries, 67404 Illkirch, France
| | - Pascal Dollé
- Department of Development and Stem Cells, Institut de Génétique et de Biologie Moléculaire et Cellulaire, CNRS/INSERM/ULP, 1 Rue Laurent Fries, 67404 Illkirch, France
| | - Gabrielle Mengus
- Department of Functional Genomics and Cancer, Institut de Génétique et de Biologie Moléculaire et Cellulaire, CNRS/INSERM/ULP, 1 Rue Laurent Fries, 67404 Illkirch, France
| | - Irwin Davidson
- Department of Functional Genomics and Cancer, Institut de Génétique et de Biologie Moléculaire et Cellulaire, CNRS/INSERM/ULP, 1 Rue Laurent Fries, 67404 Illkirch, France
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23
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Sun X, Chuang JC, Kanchwala M, Wu L, Celen C, Li L, Liang H, Zhang S, Maples T, Nguyen LH, Wang SC, Signer RAJ, Sorouri M, Nassour I, Liu X, Xu J, Wu M, Zhao Y, Kuo YC, Wang Z, Xing C, Zhu H. Suppression of the SWI/SNF Component Arid1a Promotes Mammalian Regeneration. Cell Stem Cell 2016; 18:456-66. [PMID: 27044474 DOI: 10.1016/j.stem.2016.03.001] [Citation(s) in RCA: 93] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Revised: 01/07/2016] [Accepted: 03/02/2016] [Indexed: 01/10/2023]
Abstract
Mammals have partially lost the extensive regenerative capabilities of some vertebrates, possibly as a result of chromatin-remodeling mechanisms that enforce terminal differentiation. Here, we show that deleting the SWI/SNF component Arid1a substantially improves mammalian regeneration. Arid1a expression is suppressed in regenerating tissues, and genetic deletion of Arid1a increases tissue repair following an array of injuries. Arid1a deficiency in the liver increases proliferation, reduces tissue damage and fibrosis, and improves organ function following surgical resection and chemical injuries. Hepatocyte-specific deletion is also sufficient to increase proliferation and regeneration without excessive overgrowth, and global Arid1a disruption potentiates soft tissue healing in the ear. We show that Arid1a loss reprograms chromatin to restrict promoter access by transcription factors such as C/ebpα, which enforces differentiation, and E2F4, which suppresses cell-cycle re-entry. Thus, epigenetic reprogramming mediated by deletion of a single gene improves mammalian regeneration and suggests strategies to promote tissue repair after injury.
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Affiliation(s)
- Xuxu Sun
- Departments of Pediatrics and Internal Medicine, Children's Research Institute, Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Jen-Chieh Chuang
- Departments of Pediatrics and Internal Medicine, Children's Research Institute, Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Mohammed Kanchwala
- Bioinformatics Core, Eugene McDermott Center for Human Growth & Development, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Linwei Wu
- Departments of Pediatrics and Internal Medicine, Children's Research Institute, Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Organ Transplant Center, First Affiliated Hospital of Sun Yat-Sen University, Guangzhou 510080, China
| | - Cemre Celen
- Departments of Pediatrics and Internal Medicine, Children's Research Institute, Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Lin Li
- Departments of Pediatrics and Internal Medicine, Children's Research Institute, Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Hanquan Liang
- Bioinformatics Core, Eugene McDermott Center for Human Growth & Development, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Shuyuan Zhang
- Departments of Pediatrics and Internal Medicine, Children's Research Institute, Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Thomas Maples
- Departments of Pediatrics and Internal Medicine, Children's Research Institute, Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Liem H Nguyen
- Departments of Pediatrics and Internal Medicine, Children's Research Institute, Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA
| | - Sam C Wang
- Departments of Pediatrics and Internal Medicine, Children's Research Institute, Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Surgery, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Robert A J Signer
- Division of Regenerative Medicine, Department of Medicine, Moores Cancer Center, University of California, San Diego, La Jolla, CA 92093, USA
| | - Mahsa Sorouri
- Departments of Pediatrics and Internal Medicine, Children's Research Institute, Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Ibrahim Nassour
- Departments of Pediatrics and Internal Medicine, Children's Research Institute, Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Surgery, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Xin Liu
- Departments of Pediatrics and Internal Medicine, Children's Research Institute, Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Jian Xu
- Departments of Pediatrics and Internal Medicine, Children's Research Institute, Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Meng Wu
- Mindich Child Health and Development Institute and Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Yong Zhao
- Mindich Child Health and Development Institute and Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Yi-Chun Kuo
- Departments of Pharmacology and Biophysics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Zhong Wang
- Department of Cardiac Surgery, Cardiovascular Research Center, University of Michigan, 2800 Plymouth Road, Ann Arbor, MI 48109, USA
| | - Chao Xing
- Bioinformatics Core, Eugene McDermott Center for Human Growth & Development, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Hao Zhu
- Departments of Pediatrics and Internal Medicine, Children's Research Institute, Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
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Berasain C, Avila MA. Regulation of hepatocyte identity and quiescence. Cell Mol Life Sci 2015; 72:3831-51. [PMID: 26089250 PMCID: PMC11114060 DOI: 10.1007/s00018-015-1970-7] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2015] [Revised: 05/23/2015] [Accepted: 06/12/2015] [Indexed: 12/11/2022]
Abstract
The liver is a highly differentiated organ with a central role in metabolism, detoxification and systemic homeostasis. To perform its multiple tasks, liver parenchymal cells, the hepatocytes, express a large complement of enabling genes defining their complex phenotype. This phenotype is progressively acquired during fetal development and needs to be maintained in adulthood to guarantee the individual's survival. Upon injury or loss of functional mass, the liver displays an extraordinary regenerative response, mainly based on the proliferation of hepatocytes which otherwise are long-lived quiescent cells. Increasing observations suggest that loss of hepatocellular differentiation and quiescence underlie liver malfunction in chronic liver disease and pave the way for hepatocellular carcinoma development. Here, we briefly review the essential mechanisms leading to the acquisition of liver maturity. We also identify the key molecular factors involved in the preservation of hepatocellular homeostasis and finally discuss potential strategies to preserve liver identity and function.
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Affiliation(s)
- Carmen Berasain
- Division of Hepatology, CIMA, University of Navarra, CIBEREHD, Instituto de Investigación Sanitaria de Navarra (IdiSNA), Avda. Pio XII, n55, 31008, Pamplona, Spain.
| | - Matías A Avila
- Division of Hepatology, CIMA, University of Navarra, CIBEREHD, Instituto de Investigación Sanitaria de Navarra (IdiSNA), Avda. Pio XII, n55, 31008, Pamplona, Spain.
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25
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Herquel B, Keime C, Davidson I. No evidence for generation of alternatively spliced isoforms from the mutated Trim24 allele lacking exon 4 in mouse liver. J Hepatol 2015; 63:276-7. [PMID: 25701693 DOI: 10.1016/j.jhep.2015.02.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Revised: 02/02/2015] [Accepted: 02/04/2015] [Indexed: 12/04/2022]
Affiliation(s)
- Benjamin Herquel
- Max Planck Institute of Immunology and Epigenetics, Stubeweg 51, 79100 Freiburg im Breisgau, Germany
| | - Céline Keime
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, 1 rue Laurent Fries, 67404 Illkirch-Graffenstaden, France
| | - Irwin Davidson
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, 1 rue Laurent Fries, 67404 Illkirch-Graffenstaden, France.
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Wang LY, Liu J, Li Y, Li B, Zhang YY, Jing ZW, Yu YN, Li HX, Guo SS, Zhao YJ, Wang Z, Wang YY. Time-dependent variation of pathways and networks in a 24-hour window after cerebral ischemia-reperfusion injury. BMC SYSTEMS BIOLOGY 2015; 9:11. [PMID: 25884595 PMCID: PMC4355473 DOI: 10.1186/s12918-015-0152-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/14/2014] [Accepted: 02/17/2015] [Indexed: 12/04/2022]
Abstract
Background Cerebral ischemia-reperfusion injury may simultaneously result in functional variation of multiple genes/pathways. However, most prior time-sequence studies on its pathomechanism only focused on a single gene or pathway. Our study aimed to systematically analyze the time-dependent variation in the expression of multiple pathways and networks within 24 h after cerebral ischemia-reperfusion injury. Results By uploading 374 ischemia-related genes into the MetaCore software, the variation in the expression of multiple pathways and networks in 3 h, 12 h, and 24 h after cerebral ischemia-reperfusion injury had been analyzed. The conserved TNFR1-signaling pathway, among the top 10 pathways, was consistently enriched in 3 h, 12 h, and 24 h groups. Three overlapping pathways were found between 3 h and 12 h groups; 2 between 12 h and 24 h groups; and 1 between 3 h and 24 h groups. Five, 4, and 6 non-overlapping pathways were observed in 3 h, 12 h, and 24 h groups, respectively. Apart from pathways reported by earlier studies, we identified a novel pathway related to the time-dependent development of cerebral ischemia pathogenesis. The process of apoptosis stimulation by external signals, among the top 10 processes, was consistently enriched in 3 h, 12 h, and 24 h groups; 2, 1, and 2 processes overlapped between 3 h and 12 h groups, 12 h and 24 h groups, and 3 h and 24 h groups, respectively. Four, 5, and 5 non-overlapping processes were found in 3 h, 12 h and 24 h groups, respectively. The presence of apoptotic processes was observed in all the 3 groups; while anti-apoptotic processes only existed in 3 h and 12 h groups. Additionally, according to node degree, network comparison identified 1, 8,and 5 important genes or proteins (e.g. Pyk2, PKC, E2F1, and VEGF-A) in 3 h, 12 h, and 24 h groups, respectively. The Jaccard similarity index revealed a higher level of similarity between 12 h and 24 h groups than that between 3 h and 12 h groups. Conclusion Time-dependent treatment can be utilized to reduce apoptosis, which may activate anti-apoptotic pathways within 12 h after cerebral ischemia-reperfusion injury. Pathway and network analyses may help identify novel pathways and genes implicated in disease pathogenesis. Electronic supplementary material The online version of this article (doi:10.1186/s12918-015-0152-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Li-Ying Wang
- Institute of Basic Research in Clinical Medicine, China Academy of Chinese Medical Sciences, Dongzhimennei Nanxiaojie 16#, Beijing, 100700, China.
| | - Jun Liu
- Institute of Basic Research in Clinical Medicine, China Academy of Chinese Medical Sciences, Dongzhimennei Nanxiaojie 16#, Beijing, 100700, China.
| | - Yuan Li
- Beijing University of Chinese Medicine, No. 11 East Road, North of 3rd Ring Road, Beijing, 100029, China.
| | - Bing Li
- Institute of Information on Traditional Chinese Medicine, China Academy of Chinese Medical Sciences, Dongzhimennei Nanxiaojie 16#, Beijing, 100700, China.
| | - Ying-Ying Zhang
- Institute of Basic Research in Clinical Medicine, China Academy of Chinese Medical Sciences, Dongzhimennei Nanxiaojie 16#, Beijing, 100700, China.
| | - Zhi-Wei Jing
- China Academy of Chinese Medical Sciences, Dongzhimennei Nanxiaojie 16#, Beijing, 100700, China.
| | - Ya-Nan Yu
- Institute of Basic Research in Clinical Medicine, China Academy of Chinese Medical Sciences, Dongzhimennei Nanxiaojie 16#, Beijing, 100700, China.
| | - Hai-Xia Li
- Guang'anmen Hospital, China Academy of China Medical Sciences, No.5 Beixiange, Beijing, 100053, China.
| | - Shan-Shan Guo
- Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences, Dongzhimennei Nanxiaojie 16#, Beijing, 100700, China.
| | - Yi-Jun Zhao
- China Academy of Chinese Medical Sciences, Dongzhimennei Nanxiaojie 16#, Beijing, 100700, China.
| | - Zhong Wang
- Institute of Basic Research in Clinical Medicine, China Academy of Chinese Medical Sciences, Dongzhimennei Nanxiaojie 16#, Beijing, 100700, China.
| | - Yong-Yan Wang
- Institute of Basic Research in Clinical Medicine, China Academy of Chinese Medical Sciences, Dongzhimennei Nanxiaojie 16#, Beijing, 100700, China.
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Alpern D, Langer D, Ballester B, Le Gras S, Romier C, Mengus G, Davidson I. TAF4, a subunit of transcription factor II D, directs promoter occupancy of nuclear receptor HNF4A during post-natal hepatocyte differentiation. eLife 2014; 3:e03613. [PMID: 25209997 PMCID: PMC4359380 DOI: 10.7554/elife.03613] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Accepted: 09/09/2014] [Indexed: 12/25/2022] Open
Abstract
The functions of the TAF subunits of mammalian TFIID in physiological processes remain poorly characterised. In this study, we describe a novel function of TAFs in directing genomic occupancy of a transcriptional activator. Using liver-specific inactivation in mice, we show that the TAF4 subunit of TFIID is required for post-natal hepatocyte maturation. TAF4 promotes pre-initiation complex (PIC) formation at post-natal expressed liver function genes and down-regulates a subset of embryonic expressed genes by increased RNA polymerase II pausing. The TAF4–TAF12 heterodimer interacts directly with HNF4A and in vivo TAF4 is necessary to maintain HNF4A-directed embryonic gene expression at post-natal stages and promotes HNF4A occupancy of functional cis-regulatory elements adjacent to the transcription start sites of post-natal expressed genes. Stable HNF4A occupancy of these regulatory elements requires TAF4-dependent PIC formation highlighting that these are mutually dependent events. Local promoter-proximal HNF4A–TFIID interactions therefore act as instructive signals for post-natal hepatocyte differentiation. DOI:http://dx.doi.org/10.7554/eLife.03613.001 To decode the information contained within a gene, a number of processes need to occur. For example, the DNA sequence that makes up the gene needs to be copied to make a molecule of RNA, which is then translated to build the corresponding protein. The first steps in the manufacture of RNA involve a structure called a ‘pre-initiation complex’ moving an enzyme called RNA polymerase II to the start of the gene that needs to be copied. The pre-initiation complex is made up of many types of protein, including a set of proteins called TAFs. However, the way that these proteins work in mammals is not well understood. There are good reasons for this: proteins are often studied by seeing what happens when the protein is removed, but many TAFs are so important that removing them is lethal. Alpern et al. have now studied the function of TAF4 by removing this protein from mouse liver cells. This causes severe hypoglycemia (that is, a drop in sugar levels in the blood). Moreover, it seems as if these cells start dying before they become fully mature. In liver cells lacking TAF4, some 1408 genes that are normally turned on just after birth are not properly switched on; these genes are necessary for the metabolic functions of the liver. Furthermore, 776 genes that are normally turned off after birth continue to be expressed. It seems that the absence of TAF4 sometimes disrupts the formation of the pre-initiation complex, which would slow down the production of RNA. However, it can also have the opposite effect by increasing the activity of RNA polymerase II, hence making too many copies of RNA from some genes. Alpern et al. also find that TAF4 is needed to allow a protein called HNF4A, which is important in the development of the liver and in controlling metabolism, to interact with over 7000 important DNA sequences. Mutations in HNF4A are responsible for a syndrome known as Maturity Onset of Diabetes in the Young. The next stage in this work will be to explore if these mutations influence the interaction between HNF4A and TAF4, and if they do, whether these changes contribute to this form of diabetes. DOI:http://dx.doi.org/10.7554/eLife.03613.002
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Affiliation(s)
- Daniil Alpern
- Department of Functional Genomics and Cancer, Institut de Genetique et de Biologie Moleculaire et Cellulaire, CNRS/INSERM/UDS, Illkirch, France
| | - Diana Langer
- Department of Functional Genomics and Cancer, Institut de Genetique et de Biologie Moleculaire et Cellulaire, CNRS/INSERM/UDS, Illkirch, France
| | - Benoit Ballester
- Laboratoire TAGC, Aix-Marseille Université, UMR1090, Marseille, France
| | - Stephanie Le Gras
- Department of Functional Genomics and Cancer, Institut de Genetique et de Biologie Moleculaire et Cellulaire, CNRS/INSERM/UDS, Illkirch, France
| | - Christophe Romier
- Department of Integrated Structural Biology, Institut de Genetique et de Biologie Moleculaire et Cellulaire, CNRS/INSERM/UDS, Illkirch, France
| | - Gabrielle Mengus
- Department of Functional Genomics and Cancer, Institut de Genetique et de Biologie Moleculaire et Cellulaire, CNRS/INSERM/UDS, Illkirch, France
| | - Irwin Davidson
- Department of Functional Genomics and Cancer, Institut de Genetique et de Biologie Moleculaire et Cellulaire, CNRS/INSERM/UDS, Illkirch, France
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