1
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Huang D, Ovcharenko I. The contribution of silencer variants to human diseases. Genome Biol 2024; 25:184. [PMID: 38978133 PMCID: PMC11232194 DOI: 10.1186/s13059-024-03328-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Accepted: 06/28/2024] [Indexed: 07/10/2024] Open
Abstract
BACKGROUND Although disease-causal genetic variants have been found within silencer sequences, we still lack a comprehensive analysis of the association of silencers with diseases. Here, we profiled GWAS variants in 2.8 million candidate silencers across 97 human samples derived from a diverse panel of tissues and developmental time points, using deep learning models. RESULTS We show that candidate silencers exhibit strong enrichment in disease-associated variants, and several diseases display a much stronger association with silencer variants than enhancer variants. Close to 52% of candidate silencers cluster, forming silencer-rich loci, and, in the loci of Parkinson's-disease-hallmark genes TRIM31 and MAL, the associated SNPs densely populate clustered candidate silencers rather than enhancers displaying an overall twofold enrichment in silencers versus enhancers. The disruption of apoptosis in neuronal cells is associated with both schizophrenia and bipolar disorder and can largely be attributed to variants within candidate silencers. Our model permits a mechanistic explanation of causative SNP effects by identifying altered binding of tissue-specific repressors and activators, validated with a 70% of directional concordance using SNP-SELEX. Narrowing the focus of the analysis to individual silencer variants, experimental data confirms the role of the rs62055708 SNP in Parkinson's disease, rs2535629 in schizophrenia, and rs6207121 in type 1 diabetes. CONCLUSIONS In summary, our results indicate that advances in deep learning models for the discovery of disease-causal variants within candidate silencers effectively "double" the number of functionally characterized GWAS variants. This provides a basis for explaining mechanisms of action and designing novel diagnostics and therapeutics.
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Affiliation(s)
- Di Huang
- Intramural Research Program, National Library of Medicine, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Ivan Ovcharenko
- Intramural Research Program, National Library of Medicine, National Institutes of Health, Bethesda, MD, 20892, USA.
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den Berge KV, Chou HJ, Kunda D, Risso D, Street K, Purdom E, Dudoit S, Ngai J, Heavner W. A Latent Activated Olfactory Stem Cell State Revealed by Single Cell Transcriptomic and Epigenomic Profiling. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.26.564041. [PMID: 37961539 PMCID: PMC10634988 DOI: 10.1101/2023.10.26.564041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
The olfactory epithelium is one of the few regions of the nervous system that sustains neurogenesis throughout life. Its experimental accessibility makes it especially tractable for studying molecular mechanisms that drive neural regeneration after injury-induced cell death. In this study, we used single cell sequencing to identify major regulatory players in determining olfactory epithelial stem cell fate after acute injury. We combined gene expression and accessible chromatin profiles of individual lineage traced olfactory stem cells to predict transcription factor activity specific to different lineages and stages of recovery. We further identified a discrete stem cell state that appears poised for activation, characterized by accessible chromatin around wound response and lineage specific genes prior to their later expression in response to injury. Together these results provide evidence that a subset of quiescent olfactory epithelial stem cells are epigenetically primed to support injury-induced regeneration.
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Affiliation(s)
| | - Hsin-Jung Chou
- Department of Molecular and Cell Biology, University of California, Berkeley, CA
| | - Divya Kunda
- Molecular Neurobiology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD
| | - Davide Risso
- Department of Statistical Sciences, University of Padova, Padova, Italy
| | - Kelly Street
- Division of Biostatistics, Department of Population and Public Health Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA
| | - Elizabeth Purdom
- Department of Statistics, University of California, Berkeley, CA
| | - Sandrine Dudoit
- Department of Statistics, University of California, Berkeley, CA
- Division of Biostatistics, School of Public Health, University of California, Berkeley, CA
| | - John Ngai
- Molecular Neurobiology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD
| | - Whitney Heavner
- Molecular Neurobiology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD
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3
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Saha D, Hailu S, Hada A, Lee J, Luo J, Ranish JA, Lin YC, Feola K, Persinger J, Jain A, Liu B, Lu Y, Sen P, Bartholomew B. The AT-hook is an evolutionarily conserved auto-regulatory domain of SWI/SNF required for cell lineage priming. Nat Commun 2023; 14:4682. [PMID: 37542049 PMCID: PMC10403523 DOI: 10.1038/s41467-023-40386-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Accepted: 07/26/2023] [Indexed: 08/06/2023] Open
Abstract
The SWI/SNF ATP-dependent chromatin remodeler is a master regulator of the epigenome, controlling pluripotency and differentiation. Towards the C-terminus of the catalytic subunit of SWI/SNF is a motif called the AT-hook that is evolutionary conserved. The AT-hook is present in many chromatin modifiers and generally thought to help anchor them to DNA. We observe however that the AT-hook regulates the intrinsic DNA-stimulated ATPase activity aside from promoting SWI/SNF recruitment to DNA or nucleosomes by increasing the reaction velocity a factor of 13 with no accompanying change in substrate affinity (KM). The changes in ATP hydrolysis causes an equivalent change in nucleosome movement, confirming they are tightly coupled. The catalytic subunit's AT-hook is required in vivo for SWI/SNF remodeling activity in yeast and mouse embryonic stem cells. The AT-hook in SWI/SNF is required for transcription regulation and activation of stage-specific enhancers critical in cell lineage priming. Similarly, growth assays suggest the AT-hook is required in yeast SWI/SNF for activation of genes involved in amino acid biosynthesis and metabolizing ethanol. Our findings highlight the importance of studying SWI/SNF attenuation versus eliminating the catalytic subunit or completely shutting down its enzymatic activity.
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Affiliation(s)
- Dhurjhoti Saha
- Department of Epigenetics and Molecular Carcinogenesis, Univ. of Texas MD Anderson Cancer Center, Houston, TX, 77230, USA
- University of Texas MD Anderson Cancer Center, Center for Cancer Epigenetics, Houston, TX, 77230, USA
| | - Solomon Hailu
- Department of Epigenetics and Molecular Carcinogenesis, Univ. of Texas MD Anderson Cancer Center, Houston, TX, 77230, USA
- University of Texas MD Anderson Cancer Center, Center for Cancer Epigenetics, Houston, TX, 77230, USA
- Illumina, 5200 Illumina Way, San Diego, CA, 92122, USA
| | - Arjan Hada
- Department of Epigenetics and Molecular Carcinogenesis, Univ. of Texas MD Anderson Cancer Center, Houston, TX, 77230, USA
- University of Texas MD Anderson Cancer Center, Center for Cancer Epigenetics, Houston, TX, 77230, USA
| | - Junwoo Lee
- Department of Epigenetics and Molecular Carcinogenesis, Univ. of Texas MD Anderson Cancer Center, Houston, TX, 77230, USA
- University of Texas MD Anderson Cancer Center, Center for Cancer Epigenetics, Houston, TX, 77230, USA
| | - Jie Luo
- Institute for Systems Biology, Seattle, WA, 98109, USA
| | - Jeff A Ranish
- Institute for Systems Biology, Seattle, WA, 98109, USA
| | - Yuan-Chi Lin
- Department of Epigenetics and Molecular Carcinogenesis, Univ. of Texas MD Anderson Cancer Center, Houston, TX, 77230, USA
- University of Texas MD Anderson Cancer Center, Center for Cancer Epigenetics, Houston, TX, 77230, USA
- BioAgilytix, Durham, NC, 27713, USA
| | - Kyle Feola
- Department of Epigenetics and Molecular Carcinogenesis, Univ. of Texas MD Anderson Cancer Center, Houston, TX, 77230, USA
- Department of Internal Medicine (Nephrology) and Pharmacology, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Jim Persinger
- Department of Epigenetics and Molecular Carcinogenesis, Univ. of Texas MD Anderson Cancer Center, Houston, TX, 77230, USA
- University of Texas MD Anderson Cancer Center, Center for Cancer Epigenetics, Houston, TX, 77230, USA
| | - Abhinav Jain
- Department of Epigenetics and Molecular Carcinogenesis, Univ. of Texas MD Anderson Cancer Center, Houston, TX, 77230, USA
- University of Texas MD Anderson Cancer Center, Center for Cancer Epigenetics, Houston, TX, 77230, USA
| | - Bin Liu
- Department of Epigenetics and Molecular Carcinogenesis, Univ. of Texas MD Anderson Cancer Center, Houston, TX, 77230, USA
| | - Yue Lu
- Department of Epigenetics and Molecular Carcinogenesis, Univ. of Texas MD Anderson Cancer Center, Houston, TX, 77230, USA
| | - Payel Sen
- Laboratory of Genetics and Genomics, National Institute on Aging, Baltimore, MD, 21224, USA
| | - Blaine Bartholomew
- Department of Epigenetics and Molecular Carcinogenesis, Univ. of Texas MD Anderson Cancer Center, Houston, TX, 77230, USA.
- University of Texas MD Anderson Cancer Center, Center for Cancer Epigenetics, Houston, TX, 77230, USA.
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4
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Smith CM, Grow EJ, Shadle SC, Cairns BR. Multiple repeat regions within mouse DUX recruit chromatin regulators to facilitate an embryonic gene expression program. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.29.534786. [PMID: 37034731 PMCID: PMC10081216 DOI: 10.1101/2023.03.29.534786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
The embryonic transcription factor DUX regulates chromatin opening and gene expression in totipotent cleavage-stage mouse embryos, and its expression in embryonic stem cells promotes their conversion to 2-cell embryo-like cells (2CLCs) with extraembryonic potential. However, little is known regarding which domains within mouse DUX interact with particular chromatin and transcription regulators. Here, we reveal that the C-terminus of mouse DUX contains five uncharacterized ~100 amino acid (aa) repeats followed by an acidic 14 amino acid tail. Unexpectedly, structure-function approaches classify two repeats as 'active' and three as 'inactive' in cleavage/2CLC transcription program enhancement, with differences narrowed to a key 6 amino acid section. Our proximity dependent biotin ligation (BioID) approach identified factors selectively associated with active DUX repeat derivatives (including the 14aa 'tail'), including transcription and chromatin factors such as SWI/SNF (BAF) complex, as well as nucleolar factors that have been previously implicated in regulating the Dux locus. Finally, our mechanistic studies reveal cooperativity between DUX active repeats and the acidic tail in cofactor recruitment, DUX target opening, and transcription. Taken together, we provide several new insights into DUX structure-function, and mechanisms of chromatin and gene regulation.
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Affiliation(s)
- Christina M. Smith
- Howard Hughes Medical Institute, Department of Oncological Sciences and Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, UT, USA
| | - Edward J. Grow
- Howard Hughes Medical Institute, Department of Oncological Sciences and Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, UT, USA
- Green Center for Reproductive Biological Sciences, Department of Obstetrics and Gynecology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Sean C. Shadle
- Howard Hughes Medical Institute, Department of Oncological Sciences and Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, UT, USA
| | - Bradley R. Cairns
- Howard Hughes Medical Institute, Department of Oncological Sciences and Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, UT, USA
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5
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Mohammed Ismail W, Mazzone A, Ghiraldini FG, Kaur J, Bains M, Munankarmy A, Bagwell MS, Safgren SL, Moore-Weiss J, Buciuc M, Shimp L, Leach KA, Duarte LF, Nagi CS, Carcamo S, Chung CY, Hasson D, Dadgar N, Zhong J, Lee JH, Couch FJ, Revzin A, Ordog T, Bernstein E, Gaspar-Maia A. MacroH2A histone variants modulate enhancer activity to repress oncogenic programs and cellular reprogramming. Commun Biol 2023; 6:215. [PMID: 36823213 PMCID: PMC9950461 DOI: 10.1038/s42003-023-04571-1] [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: 10/03/2022] [Accepted: 02/09/2023] [Indexed: 02/25/2023] Open
Abstract
Considerable efforts have been made to characterize active enhancer elements, which can be annotated by accessible chromatin and H3 lysine 27 acetylation (H3K27ac). However, apart from poised enhancers that are observed in early stages of development and putative silencers, the functional significance of cis-regulatory elements lacking H3K27ac is poorly understood. Here we show that macroH2A histone variants mark a subset of enhancers in normal and cancer cells, which we coined 'macro-Bound Enhancers', that modulate enhancer activity. We find macroH2A variants localized at enhancer elements that are devoid of H3K27ac in a cell type-specific manner, indicating a role for macroH2A at inactive enhancers to maintain cell identity. In following, reactivation of macro-bound enhancers is associated with oncogenic programs in breast cancer and their repressive role is correlated with the activity of macroH2A2 as a negative regulator of BRD4 chromatin occupancy. Finally, through single cell epigenomic profiling of normal mammary stem cells derived from mice, we show that macroH2A deficiency facilitates increased activity of transcription factors associated with stem cell activity.
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Affiliation(s)
- Wazim Mohammed Ismail
- Division of Experimental Pathology, Department of Lab Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
- Center for Individualized Medicine, Epigenomics program, Mayo Clinic, Rochester, MN, USA
| | - Amelia Mazzone
- Division of Experimental Pathology, Department of Lab Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
- Center for Individualized Medicine, Epigenomics program, Mayo Clinic, Rochester, MN, USA
| | - Flavia G Ghiraldini
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Jagneet Kaur
- Division of Experimental Pathology, Department of Lab Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
- Center for Individualized Medicine, Epigenomics program, Mayo Clinic, Rochester, MN, USA
| | - Manvir Bains
- Division of Experimental Pathology, Department of Lab Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
- Center for Individualized Medicine, Epigenomics program, Mayo Clinic, Rochester, MN, USA
| | - Amik Munankarmy
- Division of Experimental Pathology, Department of Lab Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
- Center for Individualized Medicine, Epigenomics program, Mayo Clinic, Rochester, MN, USA
| | - Monique S Bagwell
- Division of Experimental Pathology, Department of Lab Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
- Center for Individualized Medicine, Epigenomics program, Mayo Clinic, Rochester, MN, USA
| | - Stephanie L Safgren
- Division of Experimental Pathology, Department of Lab Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
- Center for Individualized Medicine, Epigenomics program, Mayo Clinic, Rochester, MN, USA
| | - John Moore-Weiss
- Division of Experimental Pathology, Department of Lab Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
- Center for Individualized Medicine, Epigenomics program, Mayo Clinic, Rochester, MN, USA
| | - Marina Buciuc
- Division of Experimental Pathology, Department of Lab Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
- Center for Individualized Medicine, Epigenomics program, Mayo Clinic, Rochester, MN, USA
| | - Lynzie Shimp
- Division of Experimental Pathology, Department of Lab Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
- Center for Individualized Medicine, Epigenomics program, Mayo Clinic, Rochester, MN, USA
| | - Kelsey A Leach
- Division of Experimental Pathology, Department of Lab Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
- Center for Individualized Medicine, Epigenomics program, Mayo Clinic, Rochester, MN, USA
| | - Luis F Duarte
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Chandandeep S Nagi
- Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX, USA
| | - Saul Carcamo
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Tisch Cancer Institute Bioinformatics for Next Generation Sequencing (BiNGS) Shared Resource Facility, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Chi-Yeh Chung
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Dan Hasson
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Tisch Cancer Institute Bioinformatics for Next Generation Sequencing (BiNGS) Shared Resource Facility, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Neda Dadgar
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, USA
| | - Jian Zhong
- Center for Individualized Medicine, Epigenomics program, Mayo Clinic, Rochester, MN, USA
| | - Jeong-Heon Lee
- Division of Experimental Pathology, Department of Lab Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
- Center for Individualized Medicine, Epigenomics program, Mayo Clinic, Rochester, MN, USA
| | - Fergus J Couch
- Division of Experimental Pathology, Department of Lab Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
| | - Alexander Revzin
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, USA
| | - Tamas Ordog
- Center for Individualized Medicine, Epigenomics program, Mayo Clinic, Rochester, MN, USA
| | - Emily Bernstein
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Alexandre Gaspar-Maia
- Division of Experimental Pathology, Department of Lab Medicine and Pathology, Mayo Clinic, Rochester, MN, USA.
- Center for Individualized Medicine, Epigenomics program, Mayo Clinic, Rochester, MN, USA.
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Wei Z, Xu J, Li W, Ou L, Zhou Y, Wang Y, Shi B. SMARCC1 Enters the Nucleus via KPNA2 and Plays an Oncogenic Role in Bladder Cancer. Front Mol Biosci 2022; 9:902220. [PMID: 35669562 PMCID: PMC9163745 DOI: 10.3389/fmolb.2022.902220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Accepted: 05/02/2022] [Indexed: 11/25/2022] Open
Abstract
Background: SWI/SNF-related, matrix-associated, actin-dependent regulator of chromatin subfamily C member 1 (SMARCC1), a component of the SWI/SNF complex, is thought to be an oncogene in several kinds of cancer. Materials and methods: The potential interaction between SMARCC1 and KPNA2 was inquired by Spearman’s correlation analysis, immunofluorescence staining and co-immunoprecipitation (Co-IP) assays. The immunohistochemistry staining, RT-PCR and western blot assay were taken for determining the expression levels of SMARCC1. And CCK-8, transwell assay, cell apoptosis assay, cell cycle analysis and subcutaneous tumor model were conducted to explore the role of SMARCC1 in carcinogenesis of bladder cancer. Results: In our experiments, Spearman’s correlation analysis, immunofluorescence staining and co-immunoprecipitation (Co-IP) assays showed that SMARCC1 interacted with KPNA2, and after knockdown of KPNA2, Nup50 and Nup153, the nuclear content of SMARCC1 decreased while the amount of SMARCC1 protein remaining in the cytoplasm increased, indicating that SMARCC1 could be transported into the nucleus via KPNA2 and thus acted as an oncogene. We found that both the mRNA and protein expression levels of SMARCC1 were increased in bladder cancer, and increased SMARCC1 expression was significantly associated with a higher T stage and poorer prognosis in bladder cancer patients. Knockdown of SMARCC1 slowed the growth of the two tested cell lines and clearly arrested the cell cycle at the G0/G1 phase checkpoint. Moreover, the migratory ability was significantly decreased and the number of apoptotic cells was increased. Conclusion: On the whole, our results demonstrate KPNA2, Nup50 and Nup153 regulate the process of SMARCC1 nuclear translocation in BC. SMARCC1 may be a competent candidate as a diagnostic and therapeutic target for BC. Further studies are required to research the mechanism and assess the role of SMARCC1 in vivo.
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Affiliation(s)
- Zhengmao Wei
- Department of Urology, Peking University Shenzhen Hospital, Shenzhen, China
- Department of Urology, Shenzhen Second People’s Hospital, The First Affiliated Hospital of Shenzhen University, Shenzhen, China
| | - Jinming Xu
- Department of Urology, Shenzhen Second People’s Hospital, The First Affiliated Hospital of Shenzhen University, Shenzhen, China
| | - Weiqing Li
- Karamay Central Hospital of Xinjiang, Karamay, China
| | - Longhua Ou
- Department of Urology, Shenzhen Second People’s Hospital, The First Affiliated Hospital of Shenzhen University, Shenzhen, China
| | - Yingchen Zhou
- Department of Surgery, Fuwai Hospital Chinese Academy of Medical Sciences Shenzhen, University of South China, Shenzhen, China
| | - Yan Wang
- Department of Urology, Peking University Shenzhen Hospital, Shenzhen, China
- *Correspondence: Yan Wang, ; Bentao Shi,
| | - Bentao Shi
- Department of Urology, Shenzhen Second People’s Hospital, The First Affiliated Hospital of Shenzhen University, Shenzhen, China
- *Correspondence: Yan Wang, ; Bentao Shi,
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7
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Li D, Yang J, Huang X, Zhou H, Wang J. eIF4A2 targets developmental potency and histone H3.3 transcripts for translational control of stem cell pluripotency. SCIENCE ADVANCES 2022; 8:eabm0478. [PMID: 35353581 PMCID: PMC8967233 DOI: 10.1126/sciadv.abm0478] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Accepted: 02/07/2022] [Indexed: 06/14/2023]
Abstract
Translational control has emerged as a fundamental regulatory layer of proteome complexity that governs cellular identity and functions. As initiation is the rate-limiting step of translation, we carried out an RNA interference screen for key translation initiation factors required to maintain embryonic stem cell (ESC) identity. We identified eukaryotic translation initiation factor 4A2 (eIF4A2) and defined its mechanistic action through ribosomal protein S26-independent and -dependent ribosomes in translation initiation activation of messenger RNAs (mRNAs) encoding pluripotency factors and the histone variant H3.3 with demonstrated roles in maintaining stem cell pluripotency. eIF4A2 also mediates translation initiation activation of Ddx6, which acts together with eIF4A2 to restrict the totipotent two-cell transcription program in ESCs through Zscan4 mRNA degradation and translation repression. Accordingly, knockdown of eIF4A2 disrupts ESC proteome, causing the loss of ESC identity. Collectively, we establish a translational paradigm of the protein synthesis of pluripotency transcription factors and epigenetic regulators imposed on their established roles in controlling pluripotency.
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Affiliation(s)
- Dan Li
- Department of Medicine, Columbia Center for Human Development, Columbia Stem Cell Initiative, Herbert Irving Comprehensive Cancer Center, Columbia University Irving Medical Center, New York, NY 10032, USA
- Department of Cell, Developmental, and Regenerative Biology, Black Family Stem Cell Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Jihong Yang
- Department of Medicine, Columbia Center for Human Development, Columbia Stem Cell Initiative, Herbert Irving Comprehensive Cancer Center, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Xin Huang
- Department of Medicine, Columbia Center for Human Development, Columbia Stem Cell Initiative, Herbert Irving Comprehensive Cancer Center, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Hongwei Zhou
- Department of Medicine, Columbia Center for Human Development, Columbia Stem Cell Initiative, Herbert Irving Comprehensive Cancer Center, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Jianlong Wang
- Department of Medicine, Columbia Center for Human Development, Columbia Stem Cell Initiative, Herbert Irving Comprehensive Cancer Center, Columbia University Irving Medical Center, New York, NY 10032, USA
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8
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Capecitabine Regulates HSP90AB1 Expression and Induces Apoptosis via Akt/SMARCC1/AP-1/ROS Axis in T Cells. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2022; 2022:1012509. [PMID: 35368874 PMCID: PMC8970866 DOI: 10.1155/2022/1012509] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Accepted: 03/10/2022] [Indexed: 11/17/2022]
Abstract
Transplant oncology is a newly emerging discipline integrating oncology, transplant medicine, and surgery and has brought malignancy treatment into a new era via transplantation. In this context, obtaining a drug with both immunosuppressive and antitumor effects can take into account the dual needs of preventing both transplant rejection and tumor recurrence in liver transplantation patients with malignancies. Capecitabine (CAP), a classic antitumor drug, has been shown to induce reactive oxygen species (ROS) production and apoptosis in tumor cells. Meanwhile, we have demonstrated that CAP can induce ROS production and apoptosis in T cells to exert immunosuppressive effects, but its underlying molecular mechanism is still unclear. In this study, metronomic doses of CAP were administered to normal mice by gavage, and the spleen was selected for quantitative proteomic and phosphoproteomic analysis. The results showed that CAP significantly reduced the expression of HSP90AB1 and SMARCC1 in the spleen. It was subsequently confirmed that CAP also significantly reduced the expression of HSP90AB1 and SMARCC1 and increased ROS and apoptosis levels in T cells. The results of in vitro experiments showed that HSP90AB1 knockdown resulted in a significant decrease in p-Akt, SMARCC1, p-c-Fos, and p-c-Jun expression levels and a significant increase in ROS and apoptosis levels. HSP90AB1 overexpression significantly inhibited CAP-induced T cell apoptosis by increasing the p-Akt, SMARCC1, p-c-Fos, and p-c-Jun expression levels and reducing the ROS level. In conclusion, HSP90AB1 is a key target of CAP-induced T cell apoptosis via Akt/SMARCC1/AP-1/ROS axis, which provides a novel understanding of CAP-induced T cell apoptosis and lays the experimental foundation for further exploring CAP as an immunosuppressant with antitumor effects to optimize the medication regimen for transplantation patients.
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Abstract
In the past several decades, the establishment of in vitro models of pluripotency has ushered in a golden era for developmental and stem cell biology. Research in this arena has led to profound insights into the regulatory features that shape early embryonic development. Nevertheless, an integrative theory of the epigenetic principles that govern the pluripotent nucleus remains elusive. Here, we summarize the epigenetic characteristics that define the pluripotent state. We cover what is currently known about the epigenome of pluripotent stem cells and reflect on the use of embryonic stem cells as an experimental system. In addition, we highlight insights from super-resolution microscopy, which have advanced our understanding of the form and function of chromatin, particularly its role in establishing the characteristically "open chromatin" of pluripotent nuclei. Further, we discuss the rapid improvements in 3C-based methods, which have given us a means to investigate the 3D spatial organization of the pluripotent genome. This has aided the adaptation of prior notions of a "pluripotent molecular circuitry" into a more holistic model, where hotspots of co-interacting domains correspond with the accumulation of pluripotency-associated factors. Finally, we relate these earlier hypotheses to an emerging model of phase separation, which posits that a biophysical mechanism may presuppose the formation of a pluripotent-state-defining transcriptional program.
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Affiliation(s)
| | - Eran Meshorer
- Department of Genetics, the Institute of Life Sciences
- Edmond and Lily Safra Center for Brain Sciences (ELSC), The Hebrew University of Jerusalem, Jerusalem, Israel 9190400
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10
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Neve B, Jonckheere N, Vincent A, Van Seuningen I. Long non-coding RNAs: the tentacles of chromatin remodeler complexes. Cell Mol Life Sci 2021; 78:1139-1161. [PMID: 33001247 PMCID: PMC11072783 DOI: 10.1007/s00018-020-03646-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Revised: 09/01/2020] [Accepted: 09/12/2020] [Indexed: 02/07/2023]
Abstract
Chromatin remodeler complexes regulate gene transcription, DNA replication and DNA repair by changing both nucleosome position and post-translational modifications. The chromatin remodeler complexes are categorized into four families: the SWI/SNF, INO80/SWR1, ISWI and CHD family. In this review, we describe the subunits of these chromatin remodeler complexes, in particular, the recently identified members of the ISWI family and novelties of the CHD family. Long non-coding (lnc) RNAs regulate gene expression through different epigenetic mechanisms, including interaction with chromatin remodelers. For example, interaction of lncBRM with BRM inhibits the SWI/SNF complex associated with a differentiated phenotype and favors assembly of a stem cell-related SWI/SNF complex. Today, over 50 lncRNAs have been shown to affect chromatin remodeler complexes and we here discuss the mechanisms involved.
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Affiliation(s)
- Bernadette Neve
- UMR9020-U1277 - CANTHER - Cancer Heterogeneity, Plasticity and Resistance to Therapies, Univ. Lille, CNRS, Inserm, CHU Lille, 59000, Lille, France.
| | - Nicolas Jonckheere
- UMR9020-U1277 - CANTHER - Cancer Heterogeneity, Plasticity and Resistance to Therapies, Univ. Lille, CNRS, Inserm, CHU Lille, 59000, Lille, France
| | - Audrey Vincent
- UMR9020-U1277 - CANTHER - Cancer Heterogeneity, Plasticity and Resistance to Therapies, Univ. Lille, CNRS, Inserm, CHU Lille, 59000, Lille, France
| | - Isabelle Van Seuningen
- UMR9020-U1277 - CANTHER - Cancer Heterogeneity, Plasticity and Resistance to Therapies, Univ. Lille, CNRS, Inserm, CHU Lille, 59000, Lille, France
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11
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Ye Y, Chen X, Zhang W. Mammalian SWI/SNF Chromatin Remodeling Complexes in Embryonic Stem Cells: Regulating the Balance Between Pluripotency and Differentiation. Front Cell Dev Biol 2021; 8:626383. [PMID: 33537314 PMCID: PMC7848206 DOI: 10.3389/fcell.2020.626383] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Accepted: 11/30/2020] [Indexed: 12/04/2022] Open
Abstract
The unique capability of embryonic stem cells (ESCs) to maintain and adjust the equilibrium between self-renewal and multi-lineage cellular differentiation contributes indispensably to the integrity of all developmental processes, leading to the advent of an organism in its adult form. The ESC fate decision to favor self-renewal or differentiation into specific cellular lineages largely depends on transcriptome modulations through gene expression regulations. Chromatin remodeling complexes play instrumental roles to promote chromatin structural changes resulting in gene expression changes that are key to the ESC fate choices governing the equilibrium between pluripotency and differentiation. BAF (Brg/Brahma-associated factors) or mammalian SWI/SNF complexes employ energy generated by ATP hydrolysis to change chromatin states, thereby governing the accessibility of transcriptional regulators that ultimately affect transcriptome and cell fate. Interestingly, the requirement of BAF complex in self-renewal and differentiation of ESCs has been recently shown by genetic studies through gene expression modulations of various BAF components in ESCs, although the precise molecular mechanisms by which BAF complex influences ESC fate choice remain largely underexplored. This review surveys these recent progresses of BAF complex on ESC functions, with a focus on its role of conditioning the pluripotency and differentiation balance of ESCs. A discussion of the mechanistic bases underlying the genetic requirements for BAF in ESC biology as well as the outcomes of its interplays with key transcription factors or other chromatin remodelers in ESCs will be highlighted.
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Affiliation(s)
- Ying Ye
- Cam-Su Genomic Resource Center, Medical College of Soochow University, Suzhou, China
| | - Xi Chen
- Department of Biology, Southern University of Science and Technology, Shenzhen, China
| | - Wensheng Zhang
- Cam-Su Genomic Resource Center, Medical College of Soochow University, Suzhou, China
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12
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Sharma M, Bhavani C, Suresh SB, Paul J, Yadav L, Ross C, Srivastava S. Gene expression profiling of CD34(+) cells from patients with myeloproliferative neoplasms. Oncol Lett 2021; 21:204. [PMID: 33574943 PMCID: PMC7816297 DOI: 10.3892/ol.2021.12465] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Accepted: 10/08/2020] [Indexed: 01/01/2023] Open
Abstract
Myeloproliferative neoplasms (MPN) are clonal disorders characterized by the increased proliferation of hematopoietic stem cell precursors and mature blood cells. Mutations of Janus kinase 2 (JAK2), Calreticulin (CALR) and MPL (myeloproliferative leukemia virus) are key driver mutations in MPN. However, the molecular profile of triple negative MPN has been a subject of ambiguity over the past few years. Mutations of, methylcytosine dioxygenase TET2, polycomb group protein ASXL1 and histone-lysine N-methyltransferase EZH2 genes have accounted for certain subsets of triple negative MPNs but the driving cause for majority of cases is still unexplored. The present study performed a microarray-based transcriptomic profile analysis of bone marrow-derived CD34(+) cells from seven MPN samples. A total of 21,448 gene signatures were obtained, which were further filtered into 472 upregulated and 202 downregulated genes. Gene ontology and protein-protein interaction (PPI) network analysis highlighted an upregulation of genes involved in cell cycle and chromatin modification in JAK2V617F negative vs. positive MPN samples. Out of the upregulated genes, seven were associated with the hematopoietic stem cell signature, while forty-seven were associated with the embryonic stem cell signature. The majority of the genes identified were under the control of NANOG and E2F4 transcription factors. The PPI network indicated a strong interaction between chromatin modifiers and cell cycle genes, such as histone-lysine N-methyltransferase SUV39H1, SWI/SNF complex subunit SMARCC2, SMARCE2, chromatin remodeling complex subunit SS18, tubulin β (TUBB) and cyclin dependent kinase CDK1. Among the upregulated epigenetic markers, there was a ~10-fold increase in MYB expression in JAK2V617F negative samples. A significant increase in total CD34 counts in JAK2V617F negative vs. positive samples (P<0.05) was also observed. Overall, the present data showed a distinct pattern of expression in JAK2V617F negative vs. positive samples with upregulated genes involved in epigenetic modification.
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Affiliation(s)
- Mugdha Sharma
- Department of Medicine, St. John's Medical College and Hospital, Bengaluru, Karnataka 560034, India
| | - Chandra Bhavani
- St. John's Research Institute, St. John's National Academy of Health Sciences, Bengaluru, Karnataka 560034, India
| | - Srinag Bangalore Suresh
- Department of Medicine, St. John's Medical College and Hospital, Bengaluru, Karnataka 560034, India
| | - John Paul
- Department of Medicine, St. John's Medical College and Hospital, Bengaluru, Karnataka 560034, India
| | - Lokendra Yadav
- Department of Transfusion Medicine and Immunohematology, St. John's Medical College and Hospital, Bengaluru, Karnataka 560034, India
| | - Cecil Ross
- Department of Medicine, St. John's Medical College and Hospital, Bengaluru, Karnataka 560034, India
| | - Sweta Srivastava
- Department of Transfusion Medicine and Immunohematology, St. John's Medical College and Hospital, Bengaluru, Karnataka 560034, India
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13
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Shalini V, Bhaduri U, Ravikkumar AC, Rengarajan A, Satyanarayana RMR. Genome-wide occupancy reveals the localization of H1T2 (H1fnt) to repeat regions and a subset of transcriptionally active chromatin domains in rat spermatids. Epigenetics Chromatin 2021; 14:3. [PMID: 33407810 PMCID: PMC7788777 DOI: 10.1186/s13072-020-00376-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Accepted: 11/23/2020] [Indexed: 11/10/2022] Open
Abstract
Background H1T2/H1FNT is a germ cell-specific linker histone variant expressed during spermiogenesis specifically in round and elongating spermatids. Infertile phenotype of homozygous H1T2 mutant male mice revealed the essential function of H1T2 for the DNA condensation and histone-to-protamine replacement in spermiogenesis. However, the mechanism by which H1T2 imparts the inherent polarity within spermatid nucleus including the additional protein partners and the genomic domains occupied by this linker histone are unknown. Results Sequence analysis revealed the presence of Walker motif, SR domains and putative coiled-coil domains in the C-terminal domain of rat H1T2 protein. Genome-wide occupancy analysis using highly specific antibody against the CTD of H1T2 demonstrated the binding of H1T2 to the LINE L1 repeat elements and to a significant percentage of the genic regions (promoter-TSS, exons and introns) of the rat spermatid genome. Immunoprecipitation followed by mass spectrometry analysis revealed the open chromatin architecture of H1T2 occupied chromatin encompassing the H4 acetylation and other histone PTMs characteristic of transcriptionally active chromatin. In addition, the present study has identified the interacting protein partners of H1T2-associated chromatin mainly as nucleo-skeleton components, RNA-binding proteins and chaperones. Conclusions Linker histone H1T2 possesses unique domain architecture which can account for the specific functions associated with chromatin remodeling events facilitating the initiation of histone to transition proteins/protamine transition in the polar apical spermatid genome. Our results directly establish the unique function of H1T2 in nuclear shaping associated with spermiogenesis by mediating the interaction between chromatin and nucleo-skeleton, positioning the epigenetically specialized chromatin domains involved in transcription coupled histone replacement initiation towards the apical pole of round/elongating spermatids.
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Affiliation(s)
- Vasantha Shalini
- From the Chromatin Biology Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur P.O., Bangalore, 560064, India
| | - Utsa Bhaduri
- From the Chromatin Biology Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur P.O., Bangalore, 560064, India.,Department of Life Sciences, University of Trieste, Trieste, Italy.,European Union's H2020 TRIM-NET ITN, Marie Sklodowska-Curie Actions (MSCA), Leiden, The Netherlands
| | - Anjhana C Ravikkumar
- From the Chromatin Biology Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur P.O., Bangalore, 560064, India
| | - Anusha Rengarajan
- From the Chromatin Biology Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur P.O., Bangalore, 560064, India
| | - Rao M R Satyanarayana
- From the Chromatin Biology Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur P.O., Bangalore, 560064, India.
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14
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Carmel-Gross I, Levy E, Armon L, Yaron O, Waldman Ben-Asher H, Urbach A. Human Pluripotent Stem Cell Fate Regulation by SMARCB1. Stem Cell Reports 2020; 15:1037-1046. [PMID: 33125876 PMCID: PMC7664050 DOI: 10.1016/j.stemcr.2020.10.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Revised: 10/01/2020] [Accepted: 10/02/2020] [Indexed: 02/07/2023] Open
Abstract
Epigenetic regulation by the SWI/SNF complex is essential for normal self-renewal capacity and pluripotency of human pluripotent stem cells (hPSCs). It has been shown that different subunits of the complex have a distinct role in this regulation. Specifically, the SMARCB1 subunit has been shown to regulate the activity of enhancers in diverse types of cells, including hPSCs. Here, we report the establishment of conditional hPSC lines, enabling control of SMARCB1 expression from complete loss of function to significant overexpression. Using this system, we show that any deviation from normal SMARCB1 expression leads to cell differentiation. We further found that SMARCB1 expression is not required for differentiation of hPSCs into progenitor cells, but rather for later stages of differentiation. Finally, we identify SMARCB1 as a critical player in regulation of cell-cell and cell-ECM interactions in hPSCs and show that this regulation is mediated at least in part by the WNT pathway.
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Affiliation(s)
- Ilana Carmel-Gross
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 5290002, Israel
| | - Etgar Levy
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 5290002, Israel
| | - Leah Armon
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 5290002, Israel
| | - Orly Yaron
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 5290002, Israel
| | - Hiba Waldman Ben-Asher
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 5290002, Israel
| | - Achia Urbach
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 5290002, Israel.
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15
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Innis SM, Cabot B. GBAF, a small BAF sub-complex with big implications: a systematic review. Epigenetics Chromatin 2020; 13:48. [PMID: 33143733 PMCID: PMC7607862 DOI: 10.1186/s13072-020-00370-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Accepted: 10/23/2020] [Indexed: 12/01/2022] Open
Abstract
ATP-dependent chromatin remodeling by histone-modifying enzymes and chromatin remodeling complexes is crucial for maintaining chromatin organization and facilitating gene transcription. In the SWI/SNF family of ATP-dependent chromatin remodelers, distinct complexes such as BAF, PBAF, GBAF, esBAF and npBAF/nBAF are of particular interest regarding their implications in cellular differentiation and development, as well as in various diseases. The recently identified BAF subcomplex GBAF is no exception to this, and information is emerging linking this complex and its components to crucial events in mammalian development. Furthermore, given the essential nature of many of its subunits in maintaining effective chromatin remodeling function, it comes as no surprise that aberrant expression of GBAF complex components is associated with disease development, including neurodevelopmental disorders and numerous malignancies. It becomes clear that building upon our knowledge of GBAF and BAF complex function will be essential for advancements in both mammalian reproductive applications and the development of more effective therapeutic interventions and strategies. Here, we review the roles of the SWI/SNF chromatin remodeling subcomplex GBAF and its subunits in mammalian development and disease.
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Affiliation(s)
- Sarah M Innis
- Department of Animal Sciences, Purdue University, West Lafayette, IN, USA
| | - Birgit Cabot
- Department of Animal Sciences, Purdue University, West Lafayette, IN, USA.
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16
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Ameneiro C, Moreira T, Fuentes-Iglesias A, Coego A, Garcia-Outeiral V, Escudero A, Torrecilla D, Mulero-Navarro S, Carvajal-Gonzalez JM, Guallar D, Fidalgo M. BMAL1 coordinates energy metabolism and differentiation of pluripotent stem cells. Life Sci Alliance 2020; 3:e201900534. [PMID: 32284354 PMCID: PMC7156282 DOI: 10.26508/lsa.201900534] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Revised: 03/31/2020] [Accepted: 04/01/2020] [Indexed: 11/24/2022] Open
Abstract
BMAL1 is essential for the regulation of circadian rhythms in differentiated cells and adult stem cells, but the molecular underpinnings of its function in pluripotent cells, which hold a great potential in regenerative medicine, remain to be addressed. Here, using transient and permanent loss-of-function approaches in mouse embryonic stem cells (ESCs), we reveal that although BMAL1 is dispensable for the maintenance of the pluripotent state, its depletion leads to deregulation of transcriptional programs linked to cell differentiation commitment. We further confirm that depletion of Bmal1 alters the differentiation potential of ESCs in vitro. Mechanistically, we demonstrate that BMAL1 participates in the regulation of energy metabolism maintaining a low mitochondrial function which is associated with pluripotency. Loss-of-function of Bmal1 leads to the deregulation of metabolic gene expression associated with a shift from glycolytic to oxidative metabolism. Our results highlight the important role that BMAL1 plays at the exit of pluripotency in vitro and provide evidence implicating a non-canonical circadian function of BMAL1 in the metabolic control for cell fate determination.
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Affiliation(s)
- Cristina Ameneiro
- Center for Research in Molecular Medicine and Chronic Diseases (CIMUS), Universidade de Santiago de Compostela (USC)-Health Research Institute (IDIS), Santiago de Compostela, Spain
| | - Tiago Moreira
- Center for Research in Molecular Medicine and Chronic Diseases (CIMUS), Universidade de Santiago de Compostela (USC)-Health Research Institute (IDIS), Santiago de Compostela, Spain
| | - Alejandro Fuentes-Iglesias
- Center for Research in Molecular Medicine and Chronic Diseases (CIMUS), Universidade de Santiago de Compostela (USC)-Health Research Institute (IDIS), Santiago de Compostela, Spain
- Department of Physiology, USC, Santiago de Compostela, Spain
| | - Alba Coego
- Center for Research in Molecular Medicine and Chronic Diseases (CIMUS), Universidade de Santiago de Compostela (USC)-Health Research Institute (IDIS), Santiago de Compostela, Spain
| | - Vera Garcia-Outeiral
- Center for Research in Molecular Medicine and Chronic Diseases (CIMUS), Universidade de Santiago de Compostela (USC)-Health Research Institute (IDIS), Santiago de Compostela, Spain
- Department of Physiology, USC, Santiago de Compostela, Spain
| | - Adriana Escudero
- Center for Research in Molecular Medicine and Chronic Diseases (CIMUS), Universidade de Santiago de Compostela (USC)-Health Research Institute (IDIS), Santiago de Compostela, Spain
- Department of Physiology, USC, Santiago de Compostela, Spain
| | - Daniel Torrecilla
- Center for Research in Molecular Medicine and Chronic Diseases (CIMUS), Universidade de Santiago de Compostela (USC)-Health Research Institute (IDIS), Santiago de Compostela, Spain
| | - Sonia Mulero-Navarro
- Department of Biochemistry, Molecular Biology and Genetics, Facultad de Ciencias, Universidad de Extremadura, Badajoz, Spain
| | - Jose Maria Carvajal-Gonzalez
- Department of Biochemistry, Molecular Biology and Genetics, Facultad de Ciencias, Universidad de Extremadura, Badajoz, Spain
| | - Diana Guallar
- Center for Research in Molecular Medicine and Chronic Diseases (CIMUS), Universidade de Santiago de Compostela (USC)-Health Research Institute (IDIS), Santiago de Compostela, Spain
- Department of Biochemistry and Molecular Biology, USC, Santiago de Compostela, Spain
| | - Miguel Fidalgo
- Center for Research in Molecular Medicine and Chronic Diseases (CIMUS), Universidade de Santiago de Compostela (USC)-Health Research Institute (IDIS), Santiago de Compostela, Spain
- Department of Physiology, USC, Santiago de Compostela, Spain
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17
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Li QV, Rosen BP, Huangfu D. Decoding pluripotency: Genetic screens to interrogate the acquisition, maintenance, and exit of pluripotency. WILEY INTERDISCIPLINARY REVIEWS. SYSTEMS BIOLOGY AND MEDICINE 2020; 12:e1464. [PMID: 31407519 PMCID: PMC6898739 DOI: 10.1002/wsbm.1464] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Revised: 05/31/2019] [Accepted: 07/17/2019] [Indexed: 01/25/2023]
Abstract
Pluripotent stem cells have the ability to unlimitedly self-renew and differentiate to any somatic cell lineage. A number of systems biology approaches have been used to define this pluripotent state. Complementary to systems level characterization, genetic screens offer a unique avenue to functionally interrogate the pluripotent state and identify the key players in pluripotency acquisition and maintenance, exit of pluripotency, and lineage differentiation. Here we review how genetic screens have helped us decode pluripotency regulation. We will summarize results from RNA interference (RNAi) based screens, discuss recent advances in CRISPR/Cas-based genetic perturbation methods, and how these advances have made it possible to more comprehensively interrogate pluripotency and differentiation through genetic screens. Such investigations will not only provide a better understanding of this unique developmental state, but may enhance our ability to use pluripotent stem cells as an experimental model to study human development and disease progression. Functional interrogation of pluripotency also provides a valuable roadmap for utilizing genetic perturbation to gain systems level understanding of additional cellular states, from later stages of development to pathological disease states. This article is categorized under: Developmental Biology > Stem Cell Biology and Regeneration Developmental Biology > Developmental Processes in Health and Disease Biological Mechanisms > Cell Fates.
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Affiliation(s)
- Qing V. Li
- Sloan Kettering Institute, 1275 York Avenue, New York, New York 10065, USA
- Louis V. Gerstner Jr. Graduate School of Biomedical Sciences, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, New York 10065, USA
- These authors contributed equally
| | - Bess P. Rosen
- Sloan Kettering Institute, 1275 York Avenue, New York, New York 10065, USA
- Weill Graduate School of Medical Sciences at Cornell University, 1300 York Avenue, New York, New York 10065, USA
- These authors contributed equally
| | - Danwei Huangfu
- Sloan Kettering Institute, 1275 York Avenue, New York, New York 10065, USA
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18
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Abstract
In this issue of Stem Cell Reports, Hastreiter et al. (2018) use continuous time-lapse imaging of mouse embryonic stem cells to investigate how the inhibition of GSK3b and MEK/ERK (2i) leads to homogeneous expression of the transcription factor Nanog. They show that both induction of Nanog expression and selection against cells expressing low levels of Nanog contribute to the homogeneous appearance of 2i cultures.
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Affiliation(s)
- Pablo Navarro
- Epigenetics of Stem Cells, Department of Developmental & Stem Cell Biology, Institut Pasteur, CNRS UMR 3738, 25 rue du docteur Roux, 75015 Paris, France.
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19
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Langer LF, Ward JM, Archer TK. Tumor suppressor SMARCB1 suppresses super-enhancers to govern hESC lineage determination. eLife 2019; 8:45672. [PMID: 31033435 PMCID: PMC6538374 DOI: 10.7554/elife.45672] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 04/29/2019] [Indexed: 12/13/2022] Open
Abstract
The SWI/SNF complex is a critical regulator of pluripotency in human embryonic stem cells (hESCs), and individual subunits have varied and specific roles during development and in diseases. The core subunit SMARCB1 is required for early embryonic survival, and mutations can give rise to atypical teratoid/rhabdoid tumors (AT/RTs) in the pediatric central nervous system. We report that in contrast to other studied systems, SMARCB1 represses bivalent genes in hESCs and antagonizes chromatin accessibility at super-enhancers. Moreover, and consistent with its established role as a CNS tumor suppressor, we find that SMARCB1 is essential for neural induction but dispensable for mesodermal or endodermal differentiation. Mechanistically, we demonstrate that SMARCB1 is essential for hESC super-enhancer silencing in neural differentiation conditions. This genomic assessment of hESC chromatin regulation by SMARCB1 reveals a novel positive regulatory function at super-enhancers and a unique lineage-specific role in regulating hESC differentiation. Our bodies contain trillions of cells that play a wide variety of roles. Despite looking and behaving very differently to one another, all of these ‘mature’ cells somehow descend from a single fertilized egg that contains just one set of genes. This process is partially controlled by how ‘accessible’ genetic material is to the cell machinery that switches genes on or off. For example, in immature brain cells, genes required for memory are accessible, but genes needed to produce bone are not. The developing embryo needs to control gene accessibility carefully to ensure that the right genes become available at the right time, and that crucial genes are not incorrectly ‘hidden’. In humans, the protein SMARCB1 plays an important role in this process: if damaged or deleted, development will be severely disrupted, sometimes causing brain cancer early in life. However, it remains unclear how exactly SMARCB1 regulates the accessibility of its ‘target’ genes. Now, Langer et al. set out to answer this question, and also to determine which parts of the body need SMARCB1 to develop properly. Human stem cells can develop into multiple mature cell types if given the right signals. Langer et al. found reducing levels of SMARCB1 prevented stem cells from maturing into brain cells, but not other kinds of cells. This suggests that SMARCB1 has a specific role in brain development, which is consistent with its devastating effect on brain health when damaged. A detailed analysis of genetic activity and DNA accessibility showed that SMARCB1 was doing this by switching off specific regions of DNA, called stem cell super-enhancers. These regions normally enhance the activity of genes that maintain stem cells in their immature state: when certain super-enhancers are turned off by SMARCB1, this allows stem cells to progress towards a brain cell fate. These results help us understand why damage to SMARCB1 during development causes brain cancer more often than other kinds of cancer. In the future, they could also help explain how certain types of cancer form, which would be the first step towards knowing how to treat them.
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Affiliation(s)
- Lee F Langer
- Laboratory of Epigenetics and Stem Cell Biology, National Institute of Environmental Health Sciences, National Institutes of Health, Durham, United States.,Postdoctoral Research Associate Program, National Institute of General Medical Sciences, National Institutes of Health, Bethesda, United States
| | - James M Ward
- Laboratory of Epigenetics and Stem Cell Biology, National Institute of Environmental Health Sciences, National Institutes of Health, Durham, United States.,Integrative Bioinformatics, National Institute of Environmental Health Sciences, National Institutes of Health, Durham, United States
| | - Trevor K Archer
- Laboratory of Epigenetics and Stem Cell Biology, National Institute of Environmental Health Sciences, National Institutes of Health, Durham, United States
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20
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Xie Y, Castro-Hernández R, Sokpor G, Pham L, Narayanan R, Rosenbusch J, Staiger JF, Tuoc T. RBM15 Modulates the Function of Chromatin Remodeling Factor BAF155 Through RNA Methylation in Developing Cortex. Mol Neurobiol 2019; 56:7305-7320. [PMID: 31020615 DOI: 10.1007/s12035-019-1595-1] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Accepted: 04/02/2019] [Indexed: 12/14/2022]
Abstract
Chromatin remodeling factor BAF155 is an important regulator of many biological processes. As a core and scaffold subunit of the BAF (SWI/SNF-like) complex, BAF155 is capable of regulating the stability and function of the BAF complex. The spatiotemporal expression of BAF155 during embryogenesis is essential for various aspects of organogenesis, particularly in the brain development. However, our understanding of the mechanisms that regulate the expression and function of BAF155 is limited. Here, we report that RBM15, a subunit of the m6A methyltransferase complex, interacts with BAF155 mRNA and mediates BAF155 mRNA degradation through the mRNA methylation machinery. Ablation of endogenous RBM15 expression in cultured neuronal cells and in the developing cortex augmented the expression of BAF155. Conversely, RBM15 overexpression decreased BAF155 mRNA and protein levels, and perturbed BAF155 functions in vivo, including repression of BAF155-dependent transcriptional activity and delamination of apical radial glial progenitors as a hallmark of basal radial glial progenitor genesis. Furthermore, we demonstrated that the regulation of BAF155 by RBM15 depends on the activity of the mRNA methylation complex core catalytic subunit METTL3. Altogether, our findings reveal a new regulatory avenue that elucidates how BAF complex subunit stoichiometry and functional modulation are achieved in mammalian cells.
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Affiliation(s)
- Yuanbin Xie
- Institute for Neuroanatomy, University Medical Center, Georg-August-University Goettingen, 37075, Goettingen, Germany. .,DFG Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), 37075, Goettingen, Germany.
| | - Ricardo Castro-Hernández
- Institute for Neuroanatomy, University Medical Center, Georg-August-University Goettingen, 37075, Goettingen, Germany
| | - Godwin Sokpor
- Institute for Neuroanatomy, University Medical Center, Georg-August-University Goettingen, 37075, Goettingen, Germany
| | - Linh Pham
- Institute for Neuroanatomy, University Medical Center, Georg-August-University Goettingen, 37075, Goettingen, Germany
| | - Ramanathan Narayanan
- Institute for Neuroanatomy, University Medical Center, Georg-August-University Goettingen, 37075, Goettingen, Germany.,Laboratory of Systems Neuroscience, Institute for Neuroscience, Department of Health Science and Technology, Swiss Federal Institute of Technology (ETH), 8057, Zurich, Switzerland
| | - Joachim Rosenbusch
- Institute for Neuroanatomy, University Medical Center, Georg-August-University Goettingen, 37075, Goettingen, Germany
| | - Jochen F Staiger
- Institute for Neuroanatomy, University Medical Center, Georg-August-University Goettingen, 37075, Goettingen, Germany.,DFG Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), 37075, Goettingen, Germany
| | - Tran Tuoc
- Institute for Neuroanatomy, University Medical Center, Georg-August-University Goettingen, 37075, Goettingen, Germany. .,DFG Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), 37075, Goettingen, Germany.
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21
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Liu H, Zhao YR, Chen B, Ge Z, Huang JS. High expression of SMARCE1 predicts poor prognosis and promotes cell growth and metastasis in gastric cancer. Cancer Manag Res 2019; 11:3493-3509. [PMID: 31118775 PMCID: PMC6498956 DOI: 10.2147/cmar.s195137] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Accepted: 03/07/2019] [Indexed: 12/20/2022] Open
Abstract
Background: Gastric cancer (GC) is one of the most lethal cancers worldwide with a high risk for recurrence and metastasis. Therefore, further understanding of the metastatic mechanism and the development of treatment strategies are required. Although increasing evidence suggests that SWI/SNF Related, Matrix Associated, Actin Dependent Regulator of Chromatin, Subfamily E, Member 1 (SMARCE1) promotes cancer metastasis, its role in GC remains unclear. Materials and methods: GC samples (n=122) were used to investigate the association between SMARCE1 expression, patient clinicopathological features, and prognosis. The expression of SMARCE1 in GC tissues was measured using real-time polymerase chain reaction, western blotting, and immunohistochemistry. MGC-803 and AGS cells were transfected with lentivirus to upregulate or downregulate SMARCE1 expression. The roles of SMARCE1 in GC cell proliferation, migration, and invasion were determined using Cell Counting Kit-8 assay, colony formation assay, wound healing, transwell migration, and invasion assay. Nude mice models were established to observe tumorigenesis. The specific mitogen-activated protein kinase (MAPK) inhibitor U0126 was utilized to verify the involved pathway. Results: SMARCE1 was highly expressed in GC tissues and cell lines. High expression of SMARCE1 was correlated with the malignant clinicopathological characteristics of GC patients, including tumor size, depth of invasion, degree of differentiation, lymph node involvement, and TNM stage (all P<0.05). Kaplan–Meier survival analysis revealed that high SMARCE1 expression predicted poor prognosis in GC patients (P<0.01). Moreover, SMARCE1 was an independent risk factor of poor prognosis (P<0.01). Functional study revealed that overexpression of SMARCE1 markedly promoted the proliferation, migration, and invasion of GC cells in vitro and tumorigenesis in vivo. Furthermore, SMARCE1 activated the MAPK/ERK signaling pathway. U0126 significantly inhibited the SMARCE1-induced proliferation and mobility of GC cells. Conclusion: SMARCE1 promoted growth and metastasis of GC, indicating its potential usefulness as a prognostic biomarker and target for therapeutic intervention against this disease.
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Affiliation(s)
- Hao Liu
- Department of Minimally Invasive Surgery, The Second Xiangya Hospital, Central South University, Changsha, Hunan, People's Republic of China
| | - Yan-Rong Zhao
- Department of General Surgery, Xiangya Hospital, Central South University, Changsha, Hunan, People's Republic of China
| | - Bo Chen
- Department of Minimally Invasive Surgery, The Second Xiangya Hospital, Central South University, Changsha, Hunan, People's Republic of China
| | - Zheng Ge
- Department of General Surgery, Huaihe Hospital, Henan University, Kaifeng, Henan, People's Republic of China
| | - Jiang-Sheng Huang
- Department of Minimally Invasive Surgery, The Second Xiangya Hospital, Central South University, Changsha, Hunan, People's Republic of China
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22
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Chen G, Wang J. A regulatory circuitry locking pluripotent stemness to embryonic stem cell: Interaction between threonine catabolism and histone methylation. Semin Cancer Biol 2019; 57:72-78. [PMID: 30710616 DOI: 10.1016/j.semcancer.2019.01.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Revised: 01/15/2019] [Accepted: 01/23/2019] [Indexed: 12/20/2022]
Abstract
Mouse embryonic stem cell (ESC) is a prototype of pluripotent stem cell that undergoes endless self-renewal in culture without losing the pluripotency, the ability to differentiate to all somatic lineages. The self-renewal of ESC relies on a gene expression program, epigenetic state, and cellular metabolism specific to ESC. In this review, we will present the evidence to exemplify how gene regulation, chromatin methylation, and threonine catabolism are specialized to boost ESC self-renewal. It is evident that a feedforward regulatory circuitry forms at the interfaces between the transcriptional, epigenetic and metabolic control to consolidate the pluripotency of ESC.
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Affiliation(s)
- Guohua Chen
- Department of Pathology, Wayne State of University School of Medicine, United States
| | - Jian Wang
- Department of Pathology, Wayne State of University School of Medicine, United States; Cardiovascular Research Institute, Wayne State of University School of Medicine, United States.
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23
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Panepucci RA, de Souza Lima IM. Arrayed functional genetic screenings in pluripotency reprogramming and differentiation. Stem Cell Res Ther 2019; 10:24. [PMID: 30635073 PMCID: PMC6330485 DOI: 10.1186/s13287-018-1124-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Thoroughly understanding the molecular mechanisms responsible for the biological properties of pluripotent stem cells, as well as for the processes involved in reprograming, differentiation, and transition between Naïve and Primed pluripotent states, is of great interest in basic and applied research. Although pluripotent cells have been extensively characterized in terms of their transcriptome and miRNome, a comprehensive understanding of how these gene products specifically impact their biology, depends on gain- or loss-of-function experimental approaches capable to systematically interrogate their function. We review all studies carried up to date that used arrayed screening approaches to explore the function of these genetic elements on those biological contexts, using focused or genome-wide genetic libraries. We further discuss the limitations and advantages of approaches based on assays with population-level primary readouts, derived from single-parameter plate readers, or cell-level primary readouts, obtained using multiparametric flow cytometry or quantitative fluorescence microscopy (i.e., high-content screening). Finally, we discuss technical limitation and future perspectives, highlighting how the integration of screening data may lead to major advances in the field of stem cell research and therapy.
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Affiliation(s)
- Rodrigo Alexandre Panepucci
- Laboratory of Functional Biology (LFBio), Center for Cell-Based Therapy (CTC), Regional Blood Center of Ribeirão Preto, Rua Tenente Catão Roxo, 2501, Ribeirão Preto, SP CEP: 14051-140 Brazil
- Department of Genetics, Ribeirao Preto Medical School, University of São Paulo (FMRP-USP), Ribeirão Preto, SP Brazil
| | - Ildercílio Mota de Souza Lima
- Laboratory of Functional Biology (LFBio), Center for Cell-Based Therapy (CTC), Regional Blood Center of Ribeirão Preto, Rua Tenente Catão Roxo, 2501, Ribeirão Preto, SP CEP: 14051-140 Brazil
- Department of Genetics, Ribeirao Preto Medical School, University of São Paulo (FMRP-USP), Ribeirão Preto, SP Brazil
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24
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Enane FO, Saunthararajah Y, Korc M. Differentiation therapy and the mechanisms that terminate cancer cell proliferation without harming normal cells. Cell Death Dis 2018; 9:912. [PMID: 30190481 PMCID: PMC6127320 DOI: 10.1038/s41419-018-0919-9] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Revised: 07/23/2018] [Accepted: 07/24/2018] [Indexed: 12/24/2022]
Abstract
Chemotherapeutic drugs have a common intent to activate apoptosis in tumor cells. However, master regulators of apoptosis (e.g., p53, p16/CDKN2A) are frequently genetically inactivated in cancers, resulting in multidrug resistance. An alternative, p53-independent method for terminating malignant proliferation is to engage terminal-differentiation. Normally, the exponential proliferation of lineage-committed progenitors, coordinated by the master transcription factor (TF) MYC, is self-limited by forward-differentiation to terminal lineage-fates. In cancers, however, this exponential proliferation is disengaged from terminal-differentiation. The mechanisms underlying this decoupling are mostly unknown. We performed a systematic review of published literature (January 2007-June 2018) to identify gene pathways linked to differentiation-failure in three treatment-recalcitrant cancers: hepatocellular carcinoma (HCC), ovarian cancer (OVC), and pancreatic ductal adenocarcinoma (PDAC). We analyzed key gene alterations in various apoptosis, proliferation and differentiation pathways to determine whether it is possible to predict treatment outcomes and suggest novel therapies. Poorly differentiated tumors were linked to poorer survival across histologies. Our analyses suggested loss-of-function events to master TF drivers of lineage-fates and their cofactors as being linked to differentiation-failure: genomic data in TCGA and ICGC databases demonstrated frequent haploinsufficiency of lineage master TFs (e.g., GATA4/6) in poorly differentiated tumors; the coactivators that these TFs use to activate genes (e.g. ARID1A, PBRM1) were also frequently inactivated by genetic mutation and/or deletion. By contrast, corepressor components (e.g., DNMT1, EED, UHRF1, and BAZ1A/B), that oppose coactivators to repress or turn off genes, were frequently amplified instead, and the level of amplification was highest in poorly differentiated lesions. This selection by neoplastic evolution towards unbalanced activity of transcriptional corepressors suggests these enzymes as candidate targets for inhibition aiming to re-engage forward-differentiation. This notion is supported by both pre-clinical and clinical trial literature.
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Affiliation(s)
- Francis O Enane
- Department of Medicine, Indiana University School of Medicine Indianapolis, Indianapolis, IN, 46202, USA.
| | - Yogen Saunthararajah
- Department of Hematology and Oncology, Taussig Cancer Center, Cleveland Clinic, Cleveland, OH, 44195, USA
- Department of Translational Hematology and Oncology Research, Taussig Cancer Center, Cleveland Clinic, Cleveland, OH, 44195, USA
| | - Murray Korc
- Department of Medicine, Indiana University School of Medicine Indianapolis, Indianapolis, IN, 46202, USA.
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN, 46202, USA.
- The Pancreatic Cancer Signature Center at Indiana University Purdue University Indianapolis and Indiana University Simon Cancer, Indianapolis, IN, 46202, USA.
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25
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Hastreiter S, Skylaki S, Loeffler D, Reimann A, Hilsenbeck O, Hoppe PS, Coutu DL, Kokkaliaris KD, Schwarzfischer M, Anastassiadis K, Theis FJ, Schroeder T. Inductive and Selective Effects of GSK3 and MEK Inhibition on Nanog Heterogeneity in Embryonic Stem Cells. Stem Cell Reports 2018; 11:58-69. [PMID: 29779897 PMCID: PMC6066909 DOI: 10.1016/j.stemcr.2018.04.019] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Revised: 04/20/2018] [Accepted: 04/20/2018] [Indexed: 11/30/2022] Open
Abstract
Embryonic stem cells (ESCs) display heterogeneous expression of pluripotency factors such as Nanog when cultured with serum and leukemia inhibitory factor (LIF). In contrast, dual inhibition of the signaling kinases GSK3 and MEK (2i) converts ESC cultures into a state with more uniform and high Nanog expression. However, it is so far unclear whether 2i acts through an inductive or selective mechanism. Here, we use continuous time-lapse imaging to quantify the dynamics of death, proliferation, and Nanog expression in mouse ESCs after 2i addition. We show that 2i has a dual effect: it both leads to increased cell death of Nanog low ESCs (selective effect) and induces and maintains high Nanog levels (inductive effect) in single ESCs. Genetic manipulation further showed that presence of NANOG protein is important for cell viability in 2i medium. This demonstrates complex Nanog-dependent effects of 2i treatment on ESC cultures. Continuous long-term single-cell quantification of 2i effects on murine ESCs 2i enriches for a Nanog high population through a selective cell death effect 2i also upregulates Nanog expression and prevents its downregulation The viability of Nanog−/− cells is compromised in 2i
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Affiliation(s)
- Simon Hastreiter
- Department of Biosystems Science and Engineering, ETH Zurich, 4058 Basel, Switzerland; Research Unit Stem Cell Dynamics, Helmholtz Zentrum München, 85764 Neuherberg, Germany
| | - Stavroula Skylaki
- Department of Biosystems Science and Engineering, ETH Zurich, 4058 Basel, Switzerland; Research Unit Stem Cell Dynamics, Helmholtz Zentrum München, 85764 Neuherberg, Germany
| | - Dirk Loeffler
- Department of Biosystems Science and Engineering, ETH Zurich, 4058 Basel, Switzerland; Research Unit Stem Cell Dynamics, Helmholtz Zentrum München, 85764 Neuherberg, Germany
| | - Andreas Reimann
- Department of Biosystems Science and Engineering, ETH Zurich, 4058 Basel, Switzerland
| | - Oliver Hilsenbeck
- Department of Biosystems Science and Engineering, ETH Zurich, 4058 Basel, Switzerland; Research Unit Stem Cell Dynamics, Helmholtz Zentrum München, 85764 Neuherberg, Germany
| | - Philipp S Hoppe
- Department of Biosystems Science and Engineering, ETH Zurich, 4058 Basel, Switzerland; Research Unit Stem Cell Dynamics, Helmholtz Zentrum München, 85764 Neuherberg, Germany
| | - Daniel L Coutu
- Department of Biosystems Science and Engineering, ETH Zurich, 4058 Basel, Switzerland; Research Unit Stem Cell Dynamics, Helmholtz Zentrum München, 85764 Neuherberg, Germany
| | - Konstantinos D Kokkaliaris
- Department of Biosystems Science and Engineering, ETH Zurich, 4058 Basel, Switzerland; Research Unit Stem Cell Dynamics, Helmholtz Zentrum München, 85764 Neuherberg, Germany
| | - Michael Schwarzfischer
- Institute of Computational Biology, Helmholtz Zentrum München, 85764 Neuherberg, Germany
| | | | - Fabian J Theis
- Institute of Computational Biology, Helmholtz Zentrum München, 85764 Neuherberg, Germany; Department of Mathematics, Technische Universität München, 85748 Garching, Germany
| | - Timm Schroeder
- Department of Biosystems Science and Engineering, ETH Zurich, 4058 Basel, Switzerland; Research Unit Stem Cell Dynamics, Helmholtz Zentrum München, 85764 Neuherberg, Germany.
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26
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Fukuda K, Okuda A, Yusa K, Shinkai Y. A CRISPR knockout screen identifies SETDB1-target retroelement silencing factors in embryonic stem cells. Genome Res 2018; 28:846-858. [PMID: 29728365 PMCID: PMC5991520 DOI: 10.1101/gr.227280.117] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Accepted: 04/26/2018] [Indexed: 12/16/2022]
Abstract
In mouse embryonic stem cells (mESCs), the expression of provirus and endogenous retroelements is epigenetically repressed. Although many cellular factors involved in retroelement silencing have been identified, the complete molecular mechanism remains elusive. In this study, we performed a genome-wide CRISPR screen to advance our understanding of retroelement silencing in mESCs. The Moloney murine leukemia virus (MLV)–based retroviral vector MSCV-GFP, which is repressed by the SETDB1/TRIM28 pathway in mESCs, was used as a reporter provirus, and we identified more than 80 genes involved in this process. In particular, ATF7IP and the BAF complex components are linked with the repression of most of the SETDB1 targets. We characterized two factors, MORC2A and RESF1, of which RESF1 is a novel molecule in retroelement silencing. Although both factors are recruited to repress provirus, their roles in repression are different. MORC2A appears to function dependent on repressive epigenetic modifications, while RESF1 regulates repressive epigenetic modifications associated with SETDB1. Our genome-wide CRISPR screen cataloged genes which function at different levels in silencing of SETDB1-target retroelements and provides a useful resource for further molecular studies.
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Affiliation(s)
- Kei Fukuda
- Cellular Memory Laboratory, Cluster for Pioneering Research, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Akihiko Okuda
- Division of Developmental Biology, Research Center for Genomic Medicine, Saitama Medical University, 1397-1 Yamane Hidaka Saitama 350-1241, Japan
| | - Kosuke Yusa
- Wellcome Sanger Institute, Hinxton, Cambridge, CB10 1SA, United Kingdom
| | - Yoichi Shinkai
- Cellular Memory Laboratory, Cluster for Pioneering Research, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
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27
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Zhang Q, Yang Z, Shan J, Liu L, Liu C, Shen J, Chen X, Xu Y, Chen J, Ma Q, Yang L, Qian C. MicroRNA-449a maintains self-renewal in liver cancer stem-like cells by targeting Tcf3. Oncotarget 2017; 8:110187-110200. [PMID: 29299140 PMCID: PMC5746375 DOI: 10.18632/oncotarget.22705] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2017] [Accepted: 10/29/2017] [Indexed: 12/12/2022] Open
Abstract
Cancer stem cells (CSCs) are thought to be responsible for tumor invasion, metastasis, and recurrence. We previously showed that the pluripotency factor Nanog not only serves as a novel biomarker of CSCs but also potentially plays a crucial role in maintaining the self-renewal ability of liver CSCs. However, how CSCs maintain Nanog gene expression has not been elucidated. Here, we demonstrated that microRNA-449a (miR-449a) is overexpressed in poorly differentiated hepatocellular carcinoma tissues, drug-resistant liver cancer cells, cultured liver tumorspheres, and Nanog-positive liver cancer cells. The upregulation of miR-449a in non-CSCs increased stemness, whereas the downregulation of miR-449a in Nanog-positive CSCs reduced stemness. Furthermore, transcription factor 3 (TCF3), a target of miR-449a, could downregulate Nanog expression, and restoring TCF3 expression in miR-449a-expressing Nanog-negative cells abrogated cellular stemness. These data establish that the miR449a-TCF3-Nanog axis maintains stemness in liver CSCs.
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Affiliation(s)
- Qianzhen Zhang
- Key Laboratory of Biorheological Science and Technology, Ministry of Education, Bioengineering College, Chongqing University, Chongqing, 400044, China.,College of Bioengineering, Chongqing University, Chongqing, 400044, China
| | - Zhi Yang
- Center of Biological Therapy, Southwest Hospital, Third Military Medical University, Chongqing, 400038, China
| | - Juanjuan Shan
- Center of Biological Therapy, Southwest Hospital, Third Military Medical University, Chongqing, 400038, China
| | - Limei Liu
- Center of Biological Therapy, Southwest Hospital, Third Military Medical University, Chongqing, 400038, China
| | - Chungang Liu
- Center of Biological Therapy, Southwest Hospital, Third Military Medical University, Chongqing, 400038, China
| | - Junjie Shen
- Center of Biological Therapy, Southwest Hospital, Third Military Medical University, Chongqing, 400038, China
| | - Xuejiao Chen
- Center of Biological Therapy, Southwest Hospital, Third Military Medical University, Chongqing, 400038, China
| | - Yanmin Xu
- Center of Biological Therapy, Southwest Hospital, Third Military Medical University, Chongqing, 400038, China
| | - Jun Chen
- Center of Biological Therapy, Southwest Hospital, Third Military Medical University, Chongqing, 400038, China
| | - Qinghua Ma
- Center of Biological Therapy, Southwest Hospital, Third Military Medical University, Chongqing, 400038, China
| | - Li Yang
- Key Laboratory of Biorheological Science and Technology, Ministry of Education, Bioengineering College, Chongqing University, Chongqing, 400044, China.,College of Bioengineering, Chongqing University, Chongqing, 400044, China
| | - Cheng Qian
- Center of Biological Therapy, Southwest Hospital, Third Military Medical University, Chongqing, 400038, China
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28
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Cabot B, Tseng YC, Crodian JS, Cabot R. Differential expression of key subunits of SWI/SNF chromatin remodeling complexes in porcine embryos derived in vitro or in vivo. Mol Reprod Dev 2017; 84:1238-1249. [PMID: 29024220 PMCID: PMC5760298 DOI: 10.1002/mrd.22922] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Accepted: 09/26/2017] [Indexed: 12/20/2022]
Abstract
In vitro embryo production is an established method for both humans and animals, but is fraught with inferior development and health issues in offspring born after in vitro fertilization procedures. Analysis of epigenetic changes caused by exposure to in vitro conditions should shed light on potential sources of these phenotypes. Using immunocytochemistry, we investigated the localization and relative abundance of components associated with the SWI/SNF (Switch/Sucrose non‐fermentable) chromatin‐remodeling complex—including BAF155, BAF170, BAF180, BAF53A, BAF57, BAF60A, BAF45D, ARID1A, ARID1B, ARID2, SNF5, and BRD7—in oocytes and in in vitro‐produced and in vivo‐derived porcine embryos. Differences in the localization of BAF155, BAF170, BAF60A, and ARID1B among these sources indicate that improper timing of chromatin remodeling and cellular differentiation might occur in early preimplantation embryos produced and cultured in vitro.
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Affiliation(s)
- Birgit Cabot
- Department of Animal Sciences, Purdue University, West Lafayette, Indiana
| | - Yu-Chun Tseng
- Department of Animal Sciences, Purdue University, West Lafayette, Indiana
| | - Jennifer S Crodian
- Department of Animal Sciences, Purdue University, West Lafayette, Indiana
| | - Ryan Cabot
- Department of Animal Sciences, Purdue University, West Lafayette, Indiana
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29
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Zhu B, Ueda A, Song X, Horike SI, Yokota T, Akagi T. Baf53a is involved in survival of mouse ES cells, which can be compensated by Baf53b. Sci Rep 2017; 7:14059. [PMID: 29070872 PMCID: PMC5656580 DOI: 10.1038/s41598-017-14362-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Accepted: 10/10/2017] [Indexed: 12/19/2022] Open
Abstract
The human Baf (Brg1/Brm associated factor) complex, also known as the mammalian SWI/SNF chromatin-remodeling complex, is involved in a variety of cellular processes. The pluripotency and self-renewal abilities are major characteristics of embryonic stem (ES) cells and are regulated by the ES cell-specific BAF (esBAF) complex. Baf53a is one of the subunits of the esBAF complex. Here, we found that Baf53a was expressed in undifferentiated ES cells and that it interacted with Oct3/4. Analyses of tetracycline-inducible Baf53a conditional knockout ES cells revealed that the undifferentiated markers, including Nanog and Oct3/4, were expressed in Baf53a-deficient ES cells; however, growth of the cells was repressed, and expression of p53, p21, and cleaved Caspase 3 was increased. Cell death of Baf53a-deficient ES cells was rescued by overexpression of Baf53a, but not by the Baf53a M3 mutant (E388A/R389A/R390A). Interestingly, Baf53b, a homologue of Baf53a, rescued cell death of Baf53a-deficient ES cells. Baf53a-deficient ES cells overexpressing exogenous Baf53a or Baf53b remained in the undifferentiated state, proliferated, and repressed expression of p21. In summary, our findings suggest that Baf53a is involved in the survival of ES cells by regulating p53 and Caspase3, and that Baf53b is able to compensate for this functional aspect of Baf53a.
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Affiliation(s)
- Bo Zhu
- Department of Stem Cell Biology, Faculty of Medicine, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University., 13-1 Takara-machi, Kanazawa, Ishikawa, 920-8640, Japan
| | - Atsushi Ueda
- Department of Stem Cell Biology, Faculty of Medicine, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University., 13-1 Takara-machi, Kanazawa, Ishikawa, 920-8640, Japan
| | - Xiaohong Song
- Department of Stem Cell Biology, Faculty of Medicine, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University., 13-1 Takara-machi, Kanazawa, Ishikawa, 920-8640, Japan
| | - Shin-Ichi Horike
- Advanced Science Research Center, Kanazawa University. 13-1 Takara-machi, Kanazawa, Ishikawa, 920-8640, Japan
| | - Takashi Yokota
- Department of Stem Cell Biology, Faculty of Medicine, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University., 13-1 Takara-machi, Kanazawa, Ishikawa, 920-8640, Japan.
| | - Tadayuki Akagi
- Department of Stem Cell Biology, Faculty of Medicine, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University., 13-1 Takara-machi, Kanazawa, Ishikawa, 920-8640, Japan.
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30
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Wang Y, Fan C, Zheng Y, Li C. Dynamic chromatin accessibility modeled by Markov process of randomly-moving molecules in the 3D genome. Nucleic Acids Res 2017; 45:e85. [PMID: 28180283 PMCID: PMC5449544 DOI: 10.1093/nar/gkx086] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Accepted: 02/08/2017] [Indexed: 12/05/2022] Open
Abstract
Chromatin three-dimensional (3D) structure plays critical roles in gene expression regulation by influencing locus interactions and accessibility of chromatin regions. Here we propose a Markov process model to derive a chromosomal equilibrium distribution of randomly-moving molecules as a functional consequence of spatially organized genome 3D structures. The model calculates steady-state distributions (SSD) from Hi-C data as quantitative measures of each chromatin region's dynamic accessibility for transcription factors and histone modification enzymes. Different from other Hi-C derived features such as compartment A/B and interaction hubs, or traditional methods measuring chromatin accessibility such as DNase-seq and FAIRE-seq, SSD considers both chromatin–chromatin and protein–chromatin interactions. Through our model, we find that SSD could capture the chromosomal equilibrium distributions of activation histone modifications and transcription factors. Compared with compartment A/B, SSD has higher correlations with the binding of these histone modifications and transcription factors. In addition, we find that genes located in high SSD regions tend to be expressed at higher level. Furthermore, we track the change of genome organization during stem cell differentiation, and propose a two-stage model to explain the dynamic change of SSD and gene expression during differentiation, where chromatin organization genes first gain chromatin accessibility and are expressed before lineage-specific genes do. We conclude that SSD is a novel and better measure of dynamic chromatin activity and accessibility.
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Affiliation(s)
- Yinan Wang
- Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, School of Life Sciences, Peking University, Beijing 100871, China
| | - Caoqi Fan
- Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, School of Life Sciences, Peking University, Beijing 100871, China
| | - Yuxuan Zheng
- Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, School of Life Sciences, Peking University, Beijing 100871, China
| | - Cheng Li
- Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, School of Life Sciences, Peking University, Beijing 100871, China.,Center for Statistical Science, Center for Bioinformatics, Peking University, Beijing 100871, China
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31
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Hota SK, Bruneau BG. ATP-dependent chromatin remodeling during mammalian development. Development 2017; 143:2882-97. [PMID: 27531948 DOI: 10.1242/dev.128892] [Citation(s) in RCA: 158] [Impact Index Per Article: 22.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Precise gene expression ensures proper stem and progenitor cell differentiation, lineage commitment and organogenesis during mammalian development. ATP-dependent chromatin-remodeling complexes utilize the energy from ATP hydrolysis to reorganize chromatin and, hence, regulate gene expression. These complexes contain diverse subunits that together provide a multitude of functions, from early embryogenesis through cell differentiation and development into various adult tissues. Here, we review the functions of chromatin remodelers and their different subunits during mammalian development. We discuss the mechanisms by which chromatin remodelers function and highlight their specificities during mammalian cell differentiation and organogenesis.
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Affiliation(s)
- Swetansu K Hota
- Gladstone Institute of Cardiovascular Disease, San Francisco, CA 94158, USA Roddenberry Center for Stem Cell Biology and Medicine at Gladstone, San Francisco, CA 94158, USA
| | - Benoit G Bruneau
- Gladstone Institute of Cardiovascular Disease, San Francisco, CA 94158, USA Roddenberry Center for Stem Cell Biology and Medicine at Gladstone, San Francisco, CA 94158, USA Department of Pediatrics, University of California, San Francisco, CA 94143, USA Cardiovascular Research Institute, University of California, San Francisco, CA 94158, USA
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32
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Liao R, Mizzen CA. Site-specific regulation of histone H1 phosphorylation in pluripotent cell differentiation. Epigenetics Chromatin 2017; 10:29. [PMID: 28539972 PMCID: PMC5440973 DOI: 10.1186/s13072-017-0135-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Accepted: 05/11/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Structural variation among histone H1 variants confers distinct modes of chromatin binding that are important for differential regulation of chromatin condensation, gene expression and other processes. Changes in the expression and genomic distributions of H1 variants during cell differentiation appear to contribute to phenotypic differences between cell types, but few details are known about the roles of individual H1 variants and the significance of their disparate capacities for phosphorylation. In this study, we investigated the dynamics of interphase phosphorylation at specific sites in individual H1 variants during the differentiation of pluripotent NT2 and mouse embryonic stem cells and characterized the kinases involved in regulating specific H1 variant phosphorylations in NT2 and HeLa cells. RESULTS Here, we show that the global levels of phosphorylation at H1.5-Ser18 (pS18-H1.5), H1.2/H1.5-Ser173 (pS173-H1.2/5) and H1.4-Ser187 (pS187-H1.4) are regulated differentially during pluripotent cell differentiation. Enrichment of pS187-H1.4 near the transcription start site of pluripotency factor genes in pluripotent cells is markedly reduced upon differentiation, whereas pS187-H1.4 levels at housekeeping genes are largely unaltered. Selective inhibition of CDK7 or CDK9 rapidly diminishes pS187-H1.4 levels globally and its enrichment at housekeeping genes, and similar responses were observed following depletion of CDK9. These data suggest that H1.4-S187 is a bona fide substrate for CDK9, a notion that is further supported by the significant colocalization of CDK9 and pS187-H1.4 to gene promoters in reciprocal re-ChIP analyses. Moreover, treating cells with actinomycin D to inhibit transcription and trigger the release of active CDK9/P-TEFb from 7SK snRNA complexes induces the accumulation of pS187-H1.4 at promoters and gene bodies. Notably, the levels of pS187-H1.4 enrichment after actinomycin D treatment or cell differentiation reflect the extent of CDK9 recruitment at the same loci. Remarkably, the global levels of H1.5-S18 and H1.2/H1.5-S173 phosphorylation are not affected by these transcription inhibitor treatments, and selective inhibition of CDK2 does not affect the global levels of phosphorylation at H1.4-S187 or H1.5-S18. CONCLUSIONS Our data provide strong evidence that H1 variant interphase phosphorylation is dynamically regulated in a site-specific and gene-specific fashion during pluripotent cell differentiation, and that enrichment of pS187-H1.4 at genes is positively related to their transcription. H1.4-S187 is likely to be a direct target of CDK9 during interphase, suggesting the possibility that this particular phosphorylation may contribute to the release of paused RNA pol II. In contrast, the other H1 variant phosphorylations we investigated appear to be mediated by distinct kinases and further analyses are needed to determine their functional significance.
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Affiliation(s)
- Ruiqi Liao
- Department of Cell and Developmental Biology, University of Illinois at Urbana Champaign, B107 Chemistry and Life Sciences Building, MC-123 601 S. Goodwin Ave., Urbana, IL 61801 USA
| | - Craig A Mizzen
- Department of Cell and Developmental Biology, University of Illinois at Urbana Champaign, B107 Chemistry and Life Sciences Building, MC-123 601 S. Goodwin Ave., Urbana, IL 61801 USA.,Institute for Genomic Biology, University of Illinois at Urbana Champaign, Urbana, IL 61801 USA
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33
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Dey KK, Hsiao CJ, Stephens M. Visualizing the structure of RNA-seq expression data using grade of membership models. PLoS Genet 2017; 13:e1006599. [PMID: 28333934 PMCID: PMC5363805 DOI: 10.1371/journal.pgen.1006599] [Citation(s) in RCA: 79] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Accepted: 01/24/2017] [Indexed: 02/07/2023] Open
Abstract
Grade of membership models, also known as “admixture models”, “topic models” or “Latent Dirichlet Allocation”, are a generalization of cluster models that allow each sample to have membership in multiple clusters. These models are widely used in population genetics to model admixed individuals who have ancestry from multiple “populations”, and in natural language processing to model documents having words from multiple “topics”. Here we illustrate the potential for these models to cluster samples of RNA-seq gene expression data, measured on either bulk samples or single cells. We also provide methods to help interpret the clusters, by identifying genes that are distinctively expressed in each cluster. By applying these methods to several example RNA-seq applications we demonstrate their utility in identifying and summarizing structure and heterogeneity. Applied to data from the GTEx project on 53 human tissues, the approach highlights similarities among biologically-related tissues and identifies distinctively-expressed genes that recapitulate known biology. Applied to single-cell expression data from mouse preimplantation embryos, the approach highlights both discrete and continuous variation through early embryonic development stages, and highlights genes involved in a variety of relevant processes—from germ cell development, through compaction and morula formation, to the formation of inner cell mass and trophoblast at the blastocyst stage. The methods are implemented in the Bioconductor package CountClust. Gene expression profile of a biological sample (either from single cells or pooled cells) results from a complex interplay of multiple related biological processes. Consequently, for example, distal tissue samples may share a similar gene expression profile through some common underlying biological processes. Our goal here is to illustrate that grade of membership (GoM) models—an approach widely used in population genetics to cluster admixed individuals who have ancestry from multiple populations—provide an attractive approach for clustering biological samples of RNA sequencing data. The GoM model allows each biological sample to have partial memberships in multiple biologically-distinct clusters, in contrast to traditional clustering methods that partition samples into distinct subgroups. We also provide methods for identifying genes that are distinctively expressed in each cluster to help biologically interpret the results. Applied to a dataset of 53 human tissues, the GoM approach highlights similarities among biologically-related tissues and identifies distinctively-expressed genes that recapitulate known biology. Applied to gene expression data of single cells from mouse preimplantation embryos, the approach highlights both discrete and continuous variation through early embryonic development stages, and genes involved in a variety of relevant processes. Our study highlights the potential of GoM models for elucidating biological structure in RNA-seq gene expression data.
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Affiliation(s)
- Kushal K. Dey
- Department of Statistics, University of Chicago, Chicago, Illinois, United States of America
| | - Chiaowen Joyce Hsiao
- Department of Human Genetics, University of Chicago, Chicago, Illinois, United States of America
| | - Matthew Stephens
- Department of Statistics, University of Chicago, Chicago, Illinois, United States of America
- Department of Human Genetics, University of Chicago, Chicago, Illinois, United States of America
- * E-mail:
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34
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Festuccia N, Gonzalez I, Navarro P. The Epigenetic Paradox of Pluripotent ES Cells. J Mol Biol 2016; 429:1476-1503. [PMID: 27988225 DOI: 10.1016/j.jmb.2016.12.009] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2016] [Revised: 12/02/2016] [Accepted: 12/05/2016] [Indexed: 12/15/2022]
Abstract
The propagation and maintenance of gene expression programs are at the foundation of the preservation of cell identity. A large and complex set of epigenetic mechanisms enables the long-term stability and inheritance of transcription states. A key property of authentic epigenetic regulation is being independent from the instructive signals used for its establishment. This makes epigenetic regulation, particularly epigenetic silencing, extremely robust and powerful to lock regulatory states and stabilise cell identity. In line with this, the establishment of epigenetic silencing during development restricts cell potency and maintains the cell fate choices made by transcription factors (TFs). However, how more immature cells that have not yet established their definitive fate maintain their transitory identity without compromising their responsiveness to signalling cues remains unclear. A paradigmatic example is provided by pluripotent embryonic stem (ES) cells derived from a transient population of cells of the blastocyst. Here, we argue that ES cells represent an interesting "epigenetic paradox": even though they are captured in a self-renewing state characterised by extremely efficient maintenance of their identity, which is a typical manifestation of robust epigenetic regulation, they seem not to heavily rely on classical epigenetic mechanisms. Indeed, self-renewal strictly depends on the TFs that previously instructed their undifferentiated identity and relies on a particular signalling-dependent chromatin state where repressive chromatin marks play minor roles. Although this "epigenetic paradox" may underlie their exquisite responsiveness to developmental cues, it suggests that alternative mechanisms to faithfully propagate gene regulatory states might be prevalent in ES cells.
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Affiliation(s)
- Nicola Festuccia
- Epigenetics of Stem Cells, Department of Stem Cell and Developmental Biology, Institut Pasteur, CNRS UMR3738, 25 rue du Docteur Roux, 75015 Paris, France
| | - Inma Gonzalez
- Epigenetics of Stem Cells, Department of Stem Cell and Developmental Biology, Institut Pasteur, CNRS UMR3738, 25 rue du Docteur Roux, 75015 Paris, France
| | - Pablo Navarro
- Epigenetics of Stem Cells, Department of Stem Cell and Developmental Biology, Institut Pasteur, CNRS UMR3738, 25 rue du Docteur Roux, 75015 Paris, France.
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35
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Strikoudis A, Lazaris C, Trimarchi T, Galvao Neto AL, Yang Y, Ntziachristos P, Rothbart S, Buckley S, Dolgalev I, Stadtfeld M, Strahl BD, Dynlacht BD, Tsirigos A, Aifantis I. Regulation of transcriptional elongation in pluripotency and cell differentiation by the PHD-finger protein Phf5a. Nat Cell Biol 2016; 18:1127-1138. [PMID: 27749823 PMCID: PMC5083132 DOI: 10.1038/ncb3424] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Accepted: 09/15/2016] [Indexed: 12/12/2022]
Abstract
Pluripotent embryonic stem cells (ESCs) self-renew or differentiate into all tissues of the developing embryo and cell-specification factors are necessary to balance gene expression. Here we delineate the function of the PHD-finger protein 5a (Phf5a) in ESC self-renewal and ascribe its role in regulating pluripotency, cellular reprogramming, and myoblast specification. We demonstrate that Phf5a is essential for maintaining pluripotency, since depleted ESCs exhibit hallmarks of differentiation. Mechanistically, we attribute Phf5a function to the stabilization of the Paf1 transcriptional complex and control of RNA polymerase II elongation on pluripotency loci. Apart from an ESC-specific factor, we demonstrate that Phf5a controls differentiation of adult myoblasts. Our findings suggest a potent mode of regulation by the Phf5a in stem cells, which directs their transcriptional program ultimately regulating maintenance of pluripotency and cellular reprogramming.
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Affiliation(s)
- Alexandros Strikoudis
- Department of Pathology, NYU School of Medicine, New York, New York 10016, USA.,Laura &Isaac Perlmutter Cancer Center, NYU School of Medicine, New York, New York 10016, USA.,Helen L. &Martin S. Kimmel Center for Stem Cell Biology, NYU School of Medicine, New York, New York 10016, USA
| | - Charalampos Lazaris
- Department of Pathology, NYU School of Medicine, New York, New York 10016, USA.,Laura &Isaac Perlmutter Cancer Center, NYU School of Medicine, New York, New York 10016, USA.,Helen L. &Martin S. Kimmel Center for Stem Cell Biology, NYU School of Medicine, New York, New York 10016, USA.,Center for Health Informatics and Bioinformatics, NYU School of Medicine, New York, New York 10016, USA
| | - Thomas Trimarchi
- Department of Pathology, NYU School of Medicine, New York, New York 10016, USA.,Laura &Isaac Perlmutter Cancer Center, NYU School of Medicine, New York, New York 10016, USA.,Helen L. &Martin S. Kimmel Center for Stem Cell Biology, NYU School of Medicine, New York, New York 10016, USA
| | - Antonio L Galvao Neto
- Department of Pathology, NYU School of Medicine, New York, New York 10016, USA.,Ronald O. Perelman Department of Dermatology, NYU School of Medicine, New York, New York 10016, USA
| | - Yan Yang
- Department of Pathology, NYU School of Medicine, New York, New York 10016, USA.,Laura &Isaac Perlmutter Cancer Center, NYU School of Medicine, New York, New York 10016, USA
| | - Panagiotis Ntziachristos
- Department of Pathology, NYU School of Medicine, New York, New York 10016, USA.,Laura &Isaac Perlmutter Cancer Center, NYU School of Medicine, New York, New York 10016, USA.,Helen L. &Martin S. Kimmel Center for Stem Cell Biology, NYU School of Medicine, New York, New York 10016, USA
| | - Scott Rothbart
- Department of Biochemistry and Biophysics and Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, North Carolina 27599, USA
| | - Shannon Buckley
- Department of Pathology, NYU School of Medicine, New York, New York 10016, USA.,Laura &Isaac Perlmutter Cancer Center, NYU School of Medicine, New York, New York 10016, USA.,Helen L. &Martin S. Kimmel Center for Stem Cell Biology, NYU School of Medicine, New York, New York 10016, USA
| | - Igor Dolgalev
- Department of Pathology, NYU School of Medicine, New York, New York 10016, USA.,Laura &Isaac Perlmutter Cancer Center, NYU School of Medicine, New York, New York 10016, USA.,Helen L. &Martin S. Kimmel Center for Stem Cell Biology, NYU School of Medicine, New York, New York 10016, USA.,Center for Health Informatics and Bioinformatics, NYU School of Medicine, New York, New York 10016, USA.,Genome Technology Center, Office of Collaborative Science, NYU School of Medicine, New York, New York 10016, USA
| | - Matthias Stadtfeld
- Helen L. &Martin S. Kimmel Center for Stem Cell Biology, NYU School of Medicine, New York, New York 10016, USA.,Department of Cell Biology, NYU School of Medicine, New York, New York 10016, USA
| | - Brian D Strahl
- Department of Biochemistry and Biophysics and Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, North Carolina 27599, USA
| | - Brian D Dynlacht
- Department of Pathology, NYU School of Medicine, New York, New York 10016, USA.,Laura &Isaac Perlmutter Cancer Center, NYU School of Medicine, New York, New York 10016, USA
| | - Aristotelis Tsirigos
- Department of Pathology, NYU School of Medicine, New York, New York 10016, USA.,Laura &Isaac Perlmutter Cancer Center, NYU School of Medicine, New York, New York 10016, USA.,Center for Health Informatics and Bioinformatics, NYU School of Medicine, New York, New York 10016, USA
| | - Iannis Aifantis
- Department of Pathology, NYU School of Medicine, New York, New York 10016, USA.,Laura &Isaac Perlmutter Cancer Center, NYU School of Medicine, New York, New York 10016, USA.,Helen L. &Martin S. Kimmel Center for Stem Cell Biology, NYU School of Medicine, New York, New York 10016, USA
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36
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Toto PC, Puri PL, Albini S. SWI/SNF-directed stem cell lineage specification: dynamic composition regulates specific stages of skeletal myogenesis. Cell Mol Life Sci 2016; 73:3887-96. [PMID: 27207468 PMCID: PMC5158306 DOI: 10.1007/s00018-016-2273-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Revised: 05/06/2016] [Accepted: 05/10/2016] [Indexed: 11/25/2022]
Abstract
SWI/SNF chromatin-remodeling complexes are key regulators of the epigenetic modifications that determine whether stem cells maintain pluripotency or commit toward specific lineages through development and during postnatal life. Dynamic combinatorial assembly of multiple variants of SWI/SNF subunits is emerging as the major determinant of the functional versatility of SWI/SNF. Here, we summarize the current knowledge on the structural and functional properties of the alternative SWI/SNF complexes that direct stem cell fate toward skeletal muscle lineage and control distinct stages of skeletal myogenesis. In particular, we will refer to recent evidence pointing to the essential role of two SWI/SNF components not expressed in embryonic stem cells-the catalytic subunit BRM and the structural component BAF60C-whose induction in muscle progenitors coincides with the expansion of their transcriptional repertoire.
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Affiliation(s)
- Paula Coutinho Toto
- Sanford Burnham Prebys Medical Discovery Institute, 10905 Road to the Cure, San Diego, CA, 92121, USA
| | - Pier Lorenzo Puri
- Sanford Burnham Prebys Medical Discovery Institute, 10905 Road to the Cure, San Diego, CA, 92121, USA.
- IRCCS Fondazione Santa Lucia, Via del Fosso di Fiorano, 64, 00143, Rome, Italy.
| | - Sonia Albini
- Sanford Burnham Prebys Medical Discovery Institute, 10905 Road to the Cure, San Diego, CA, 92121, USA.
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37
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Sarkar P, Mischler A, Randall SM, Collier TS, Dorman KF, Boggess KA, Muddiman DC, Rao BM. Identification of Epigenetic Factor Proteins Expressed in Human Embryonic Stem Cell-Derived Trophoblasts and in Human Placental Trophoblasts. J Proteome Res 2016; 15:2433-44. [PMID: 27378238 DOI: 10.1021/acs.jproteome.5b01118] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Human embryonic stem cells (hESCs) have been used to derive trophoblasts through differentiation in vitro. Intriguingly, mouse ESCs are prevented from differentiation to trophoblasts by certain epigenetic factor proteins such as Dnmt1, thus necessitating the study of epigenetic factor proteins during hESC differentiation to trophoblasts. We used stable isotope labeling by amino acids in cell culture and quantitative proteomics to study changes in the nuclear proteome during hESC differentiation to trophoblasts and identified changes in the expression of 30 epigenetic factor proteins. Importantly, the DNA methyltransferases DNMT1, DNMT3A, and DNMT3B were downregulated. Additionally, we hypothesized that nuclear proteomics of hESC-derived trophoblasts may be used for screening epigenetic factor proteins expressed by primary trophoblasts in human placental tissue. Accordingly, we conducted immunohistochemistry analysis of six epigenetic factor proteins identified from hESC-derived trophoblasts-DNMT1, DNMT3B, BAF155, BAF60A, BAF57, and ING5-in 6-9 week human placentas. Indeed, expression of these proteins was largely, though not fully, consistent with that observed in 6-9 week placental trophoblasts. Our results support the use of hESC-derived trophoblasts as a model for placental trophoblasts, which will enable further investigation of epigenetic factors involved in human trophoblast development.
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Affiliation(s)
| | | | | | | | - Karen F Dorman
- Department of Obstetrics and Gynecology, University of North Carolina-Chapel Hill , Chapel Hill, North Carolina 27599, United States
| | - Kim A Boggess
- Department of Obstetrics and Gynecology, University of North Carolina-Chapel Hill , Chapel Hill, North Carolina 27599, United States
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38
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Pandolfini L, Luzi E, Bressan D, Ucciferri N, Bertacchi M, Brandi R, Rocchiccioli S, D'Onofrio M, Cremisi F. RISC-mediated control of selected chromatin regulators stabilizes ground state pluripotency of mouse embryonic stem cells. Genome Biol 2016; 17:94. [PMID: 27154007 PMCID: PMC4858858 DOI: 10.1186/s13059-016-0952-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2016] [Accepted: 04/13/2016] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND Embryonic stem cells are intrinsically unstable and differentiate spontaneously if they are not shielded from external stimuli. Although the nature of such instability is still controversial, growing evidence suggests that protein translation control may play a crucial role. RESULTS We performed an integrated analysis of RNA and proteins at the transition between naïve embryonic stem cells and cells primed to differentiate. During this transition, mRNAs coding for chromatin regulators are specifically released from translational inhibition mediated by RNA-induced silencing complex (RISC). This suggests that, prior to differentiation, the propensity of embryonic stem cells to change their epigenetic status is hampered by RNA interference. The expression of these chromatin regulators is reinstated following acute inactivation of RISC and it correlates with loss of stemness markers and activation of early cell differentiation markers in treated embryonic stem cells. CONCLUSIONS We propose that RISC-mediated inhibition of specific sets of chromatin regulators is a primary mechanism for preserving embryonic stem cell pluripotency while inhibiting the onset of embryonic developmental programs.
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Affiliation(s)
- Luca Pandolfini
- Scuola Normale Superiore of Pisa, Piazza dei Cavalieri, 7, 56124, Pisa, Italy
- Wellcome Trust/CRUK Gurdon Institute, Tennis Court Road, Cambridge, CB2 1QN, UK
| | - Ettore Luzi
- Department of Surgery and Translational Medicine, University of Florence, Florence, Italy
| | - Dario Bressan
- Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge, CB2 0RE, UK
| | - Nadia Ucciferri
- Institute of Clinical Physiology CNR, Via Moruzzi 1, 56124, Pisa, Italy
| | - Michele Bertacchi
- Scuola Normale Superiore of Pisa, Piazza dei Cavalieri, 7, 56124, Pisa, Italy
- University of Nice Sophia-Antipolis, Parc Valrose, 28 Avenue Valrose, F-06108, Nice, France
| | - Rossella Brandi
- Genomics Facility, European Brain Research Institute (EBRI) "Rita Levi-Montalcini", Via del Fosso di Fiorano 64, 00143, Rome, Italy
| | | | - Mara D'Onofrio
- Genomics Facility, European Brain Research Institute (EBRI) "Rita Levi-Montalcini", Via del Fosso di Fiorano 64, 00143, Rome, Italy
- Institute of Translational Pharmacology, CNR, Via del Fosso del Cavaliere 100, 00133, Rome, Italy
| | - Federico Cremisi
- Scuola Normale Superiore of Pisa, Piazza dei Cavalieri, 7, 56124, Pisa, Italy.
- Institute of Biomedical Technologies (ITB), National Research Council (CNR) of Pisa, Via Moruzzi 1, 56124, Pisa, Italy.
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39
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Panamarova M, Cox A, Wicher KB, Butler R, Bulgakova N, Jeon S, Rosen B, Seong RH, Skarnes W, Crabtree G, Zernicka-Goetz M. The BAF chromatin remodelling complex is an epigenetic regulator of lineage specification in the early mouse embryo. Development 2016; 143:1271-83. [PMID: 26952987 PMCID: PMC4852518 DOI: 10.1242/dev.131961] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Accepted: 02/22/2016] [Indexed: 12/16/2022]
Abstract
Dynamic control of gene expression is essential for the development of a totipotent zygote into an embryo with defined cell lineages. The accessibility of genes responsible for cell specification to transcriptional machinery is dependent on chromatin remodelling complexes such as the SWI\SNF (BAF) complex. However, the role of the BAF complex in early mouse development has remained unclear. Here, we demonstrate that BAF155, a major BAF complex subunit, regulates the assembly of the BAF complex in vivo and regulates lineage specification of the mouse blastocyst. We find that associations of BAF155 with other BAF complex subunits become enriched in extra-embryonic lineages just prior to implantation. This enrichment is attributed to decreased mobility of BAF155 in extra-embryonic compared with embryonic lineages. Downregulation of BAF155 leads to increased expression of the pluripotency marker Nanog and its ectopic expression in extra-embryonic lineages, whereas upregulation of BAF155 leads to the upregulation of differentiation markers. Finally, we show that the arginine methyltransferase CARM1 methylates BAF155, which differentially influences assembly of the BAF complex between the lineages and the expression of pluripotency markers. Together, our results indicate a novel role of BAF-dependent chromatin remodelling in mouse development via regulation of lineage specification. Summary: Associations of BAF155 with other BAF complex subunits are enriched in extra-embryonic lineages prior to implantation, while changes in BAF155 levels modulate the expression of early developmental markers.
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Affiliation(s)
- Maryna Panamarova
- Wellcome Trust Cancer Research UK Gurdon Institute, Tennis Court Road, Cambridge CB2 1QN, UK Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3DY, UK
| | - Andy Cox
- Wellcome Trust Cancer Research UK Gurdon Institute, Tennis Court Road, Cambridge CB2 1QN, UK Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3DY, UK
| | - Krzysztof B Wicher
- Wellcome Trust Cancer Research UK Gurdon Institute, Tennis Court Road, Cambridge CB2 1QN, UK Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3DY, UK
| | - Richard Butler
- Wellcome Trust Cancer Research UK Gurdon Institute, Tennis Court Road, Cambridge CB2 1QN, UK
| | - Natalia Bulgakova
- Wellcome Trust Cancer Research UK Gurdon Institute, Tennis Court Road, Cambridge CB2 1QN, UK Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3DY, UK Bateson Centre and Department of Biomedical Science, University of Sheffield, Western Bank, Sheffield S10 2TN, UK
| | - Shin Jeon
- Department of Biological Sciences, Institute of Molecular Biology and Genetics, Seoul National University, Seoul 151-747, South Korea
| | - Barry Rosen
- Wellcome Trust Sanger Institute, Hinxton CB10 1SA, UK
| | - Rho H Seong
- Department of Biological Sciences, Institute of Molecular Biology and Genetics, Seoul National University, Seoul 151-747, South Korea
| | | | - Gerald Crabtree
- Department of Developmental Biology, Stanford University Medical School, Stanford, CA 94305, USA
| | - Magdalena Zernicka-Goetz
- Wellcome Trust Cancer Research UK Gurdon Institute, Tennis Court Road, Cambridge CB2 1QN, UK Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3DY, UK
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40
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Ooga M, Fulka H, Hashimoto S, Suzuki MG, Aoki F. Analysis of chromatin structure in mouse preimplantation embryos by fluorescent recovery after photobleaching. Epigenetics 2016; 11:85-94. [PMID: 26901819 DOI: 10.1080/15592294.2015.1136774] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Zygotes are totipotent cells that have the ability to differentiate into all cell types. It is believed that this ability is lost gradually and differentiation occurs along with the progression of preimplantation development. Here, we hypothesized that the loose chromatin structure is involved in the totipotency of one-cell stage embryos and that the change from loose to tight chromatin structure is associated with the loss of totipotency. To address this hypothesis, we investigated the mobility of eGFP-tagged histone H2B (eGFP-H2B), which is an index for the looseness of chromatin, during preimplantation development based on fluorescent recovery after photobleaching (FRAP) analysis. The highest mobility of eGFP-H2B was observed in pronuclei in 1-cell stage embryos and mobility gradually decreased during preimplantation development. The decrease in mobility between the 1- and 2-cell stages depended on DNA synthesis in 2-cell stage embryos. In nuclear transferred embryos, chromatin in the pseudopronuclei loosened to a level comparable to the pronuclei in 1-cell stage embryos. These results indicated that the mobility of eGFP-H2B is negatively correlated with the degree of differentiation of preimplantation embryos. Therefore, we suggest that highly loosened chromatin is involved in totipotency of 1-cell embryos and the loss of looseness is associated with differentiation during preimplantation development.
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Affiliation(s)
- Masatoshi Ooga
- a Department of Integrated Biosciences , Graduate School of Frontier Sciences, The University of Tokyo , Kashiwa, Chiba , Japan
| | - Helena Fulka
- a Department of Integrated Biosciences , Graduate School of Frontier Sciences, The University of Tokyo , Kashiwa, Chiba , Japan.,b Department of Biology of Reproduction , Institute of Animal Science , Prague , Czech Republic
| | - Satoshi Hashimoto
- a Department of Integrated Biosciences , Graduate School of Frontier Sciences, The University of Tokyo , Kashiwa, Chiba , Japan
| | - Masataka G Suzuki
- a Department of Integrated Biosciences , Graduate School of Frontier Sciences, The University of Tokyo , Kashiwa, Chiba , Japan
| | - Fugaku Aoki
- a Department of Integrated Biosciences , Graduate School of Frontier Sciences, The University of Tokyo , Kashiwa, Chiba , Japan.,b Department of Biology of Reproduction , Institute of Animal Science , Prague , Czech Republic
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41
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Chatterjee SS, Saj A, Gocha T, Murphy M, Gonsalves FC, Zhang X, Hayward P, Akgöl Oksuz B, Shen SS, Madar A, Martinez Arias A, DasGupta R. Inhibition of β-catenin-TCF1 interaction delays differentiation of mouse embryonic stem cells. J Cell Biol 2016; 211:39-51. [PMID: 26459597 PMCID: PMC4602028 DOI: 10.1083/jcb.201503017] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Blocking β-catenin/TCF1–mediated transcriptional activation with a specific small molecule or by TCF1 knockdown delays the mouse embryonic stem cell differentiation program and enhances pluripotency. The ability of mouse embryonic stem cells (mESCs) to self-renew or differentiate into various cell lineages is regulated by signaling pathways and a core pluripotency transcriptional network (PTN) comprising Nanog, Oct4, and Sox2. The Wnt/β-catenin pathway promotes pluripotency by alleviating T cell factor TCF3-mediated repression of the PTN. However, it has remained unclear how β-catenin’s function as a transcriptional activator with TCF1 influences mESC fate. Here, we show that TCF1-mediated transcription is up-regulated in differentiating mESCs and that chemical inhibition of β-catenin/TCF1 interaction improves long-term self-renewal and enhances functional pluripotency. Genetic loss of TCF1 inhibited differentiation by delaying exit from pluripotency and conferred a transcriptional profile strikingly reminiscent of self-renewing mESCs with high Nanog expression. Together, our data suggest that β-catenin’s function in regulating mESCs is highly context specific and that its interaction with TCF1 promotes differentiation, further highlighting the need for understanding how its individual protein–protein interactions drive stem cell fate.
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Affiliation(s)
- Sujash S Chatterjee
- Department of Biochemistry and Molecular Pharmacology, New York University Cancer Institute, New York University Langone Medical Center, New York, NY 10016
| | - Abil Saj
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, Singapore 138672
| | - Tenzin Gocha
- Department of Biochemistry and Molecular Pharmacology, New York University Cancer Institute, New York University Langone Medical Center, New York, NY 10016
| | - Matthew Murphy
- Department of Biochemistry and Molecular Pharmacology, New York University Cancer Institute, New York University Langone Medical Center, New York, NY 10016
| | - Foster C Gonsalves
- Department of Biochemistry and Molecular Pharmacology, New York University Cancer Institute, New York University Langone Medical Center, New York, NY 10016
| | - Xiaoqian Zhang
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, Singapore 138672
| | - Penelope Hayward
- Department of Genetics, University of Cambridge, Cambridge CB2 3EH, England, UK
| | - Betül Akgöl Oksuz
- Bioinformatics Core, New York University Langone Medical Center, New York, NY 10016
| | - Steven S Shen
- Bioinformatics Core, New York University Langone Medical Center, New York, NY 10016
| | - Aviv Madar
- Department of Biological Statistics and Computational Biology, Cornell University, Ithaca, NY 14853
| | | | - Ramanuj DasGupta
- Department of Biochemistry and Molecular Pharmacology, New York University Cancer Institute, New York University Langone Medical Center, New York, NY 10016 Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, Singapore 138672
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Gonzales KAU, Ng HH. Biological Networks Governing the Acquisition, Maintenance, and Dissolution of Pluripotency: Insights from Functional Genomics Approaches. COLD SPRING HARBOR SYMPOSIA ON QUANTITATIVE BIOLOGY 2015; 80:189-98. [PMID: 26582790 DOI: 10.1101/sqb.2015.80.027326] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The repertoire of transcripts encoded by the genome contributes to the diversity of cellular states. Functional genomics aims to comprehensively uncover the roles of these transcripts to reconstruct biological networks and transform this information into useful knowledge. High-throughput functional screening has served as a powerful genetic discovery tool by enabling massively parallel implementation of biological assays. In recent years, high-throughput screening has unearthed crucial players in the regulation of different aspects of pluripotency, which is a unique property that enables a cell to differentiate into multiple cell types of the three major lineages. Pluripotency thus represents an interesting biological paradigm for studying the acquisition, maintenance, and dissolution of cellular states. In this review, we highlight the major findings of high-throughput studies to dissect these three aspects of pluripotency for the mouse and human systems. Collectively, they provide new insights into cell fate maintenance and transition. In addition, we also discuss the opportunities and challenges awaiting high-throughput screening in the future.
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Affiliation(s)
| | - Huck-Hui Ng
- Stem Cell and Regenerative Biology, Genome Institute of Singapore, Singapore 138672, Singapore Department of Biochemistry, National University of Singapore, Singapore 117597, Singapore Department of Biological Sciences, National University of Singapore, Singapore 117597, Singapore School of Biological Sciences, Nanyang Technological University, Singapore 639798, Singapore
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Regulation of Nucleosome Architecture and Factor Binding Revealed by Nuclease Footprinting of the ESC Genome. Cell Rep 2015; 13:61-69. [PMID: 26411677 DOI: 10.1016/j.celrep.2015.08.071] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Revised: 08/01/2015] [Accepted: 08/25/2015] [Indexed: 12/15/2022] Open
Abstract
Functional interactions between gene regulatory factors and chromatin architecture have been difficult to directly assess. Here, we use micrococcal nuclease (MNase) footprinting to probe the functions of two chromatin-remodeling complexes. By simultaneously quantifying alterations in small MNase footprints over the binding sites of 30 regulatory factors in mouse embryonic stem cells (ESCs), we provide evidence that esBAF and Mbd3/NuRD modulate the binding of several regulatory proteins. In addition, we find that nucleosome occupancy is reduced at specific loci in favor of subnucleosomes upon depletion of esBAF, including sites of histone H2A.Z localization. Consistent with these data, we demonstrate that esBAF is required for normal H2A.Z localization in ESCs, suggesting esBAF either stabilizes H2A.Z-containing nucleosomes or promotes subnucleosome to nucleosome conversion by facilitating H2A.Z deposition. Therefore, integrative examination of MNase footprints reveals insights into nucleosome dynamics and functional interactions between chromatin structure and key gene-regulatory factors.
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Gingold JA, Coakley ES, Su J, Lee DF, Lau Z, Zhou H, Felsenfeld DP, Schaniel C, Lemischka IR. Distribution Analyzer, a methodology for identifying and clustering outlier conditions from single-cell distributions, and its application to a Nanog reporter RNAi screen. BMC Bioinformatics 2015. [PMID: 26198214 PMCID: PMC4511455 DOI: 10.1186/s12859-015-0636-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Background Chemical or small interfering (si) RNA screens measure the effects of many independent experimental conditions, each applied to a population of cells (e.g., all of the cells in a well). High-content screens permit a readout (e.g., fluorescence, luminescence, cell morphology) from each cell in the population. Most analysis approaches compare the average effect on each population, precluding identification of outliers that affect the distribution of the reporter in the population but not its average. Other approaches only measure changes to the distribution with a single parameter, precluding accurate distinction and clustering of interesting outlier distributions. Results We describe a methodology to identify outlier conditions by considering the cell-level measurements from each condition as a sample of an underlying distribution. With appropriate selection of a distance metric, all effects can be embedded in a fixed-dimensionality Euclidean basis, facilitating identification and clustering of biologically interesting outliers. We demonstrate that measurement of distances with the Hellinger distance metric offers substantial computational efficiencies over alternative metrics. We validate this methodology using an RNA interference (RNAi) screen in mouse embryonic stem cells (ESC) with a Nanog reporter. The methodology clusters effects of multiple control siRNAs into their true identities better than conventional approaches describing the median cell fluorescence or the commonly used Kolmogorov-Smirnov distance between the observed fluorescence distribution and the null distribution. It identifies outlier genes with effects on the reporter distribution that would have been missed by other methods. Among them, siRNA targeting Chek1 leads to a wider Nanog reporter fluorescence distribution. Similarly, siRNA targeting Med14 or Med27 leads to a narrower Nanog reporter fluorescence distribution. We confirm the roles of these three genes in regulating pluripotency by mRNA expression and alkaline phosphatase staining using independent short hairpin (sh) RNAs. Conclusions Using our methodology, we describe each experimental condition by a probability distribution. Measuring distances between probability distributions permits a multivariate rather than univariate readout. Clustering points derived from these distances allows us to obtain greater biological insight than methods based solely on single parameters. We find several outliers from a mouse ESC RNAi screen that we confirm to be pluripotency regulators. Many of these outliers would have been missed by other analysis methods. Electronic supplementary material The online version of this article (doi:10.1186/s12859-015-0636-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Julian A Gingold
- The Black Family Stem Cell Institute, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA. .,Department of Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA.
| | - Ed S Coakley
- Program in Applied Mathematics, Yale University, New Haven, CT, 06511, USA.
| | - Jie Su
- The Black Family Stem Cell Institute, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA. .,Department of Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA. .,Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA.
| | - Dung-Fang Lee
- The Black Family Stem Cell Institute, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA. .,Department of Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA.
| | - Zerlina Lau
- Integrated Screening Core, Experimental Therapeutics Institute, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA.
| | - Hongwei Zhou
- The Black Family Stem Cell Institute, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA. .,Department of Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA.
| | - Dan P Felsenfeld
- The Black Family Stem Cell Institute, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA. .,Department of Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA. .,Integrated Screening Core, Experimental Therapeutics Institute, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA.
| | - Christoph Schaniel
- The Black Family Stem Cell Institute, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA. .,Department of Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA. .,Department of Pharmacology and Systems Therapeutics, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA.
| | - Ihor R Lemischka
- The Black Family Stem Cell Institute, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA. .,Department of Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA. .,Department of Pharmacology and Systems Therapeutics, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA.
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Wade SL, Langer LF, Ward JM, Archer TK. MiRNA-Mediated Regulation of the SWI/SNF Chromatin Remodeling Complex Controls Pluripotency and Endodermal Differentiation in Human ESCs. Stem Cells 2015; 33:2925-35. [PMID: 26119756 DOI: 10.1002/stem.2084] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2014] [Accepted: 06/15/2015] [Indexed: 01/07/2023]
Abstract
MicroRNAs and chromatin remodeling complexes represent powerful epigenetic mechanisms that regulate the pluripotent state. miR-302 is a strong inducer of pluripotency, which is characterized by a distinct chromatin architecture. This suggests that miR-302 regulates global chromatin structure; however, a direct relationship between miR-302 and chromatin remodelers has not been established. Here, we provide data to show that miR-302 regulates Brg1 chromatin remodeling complex composition in human embryonic stem cells (hESCs) through direct repression of the BAF53a and BAF170 subunits. With the subsequent overexpression of BAF170 in hESCs, we show that miR-302's inhibition of BAF170 protein levels can affect the expression of genes involved in cell proliferation. Furthermore, miR-302-mediated repression of BAF170 regulates pluripotency by positively influencing mesendodermal differentiation. Overexpression of BAF170 in hESCs led to biased differentiation toward the ectoderm lineage during EB formation and severely hindered directed definitive endoderm differentiation. Taken together, these data uncover a direct regulatory relationship between miR-302 and the Brg1 chromatin remodeling complex that controls gene expression and cell fate decisions in hESCs and suggests that similar mechanisms are at play during early human development.
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Affiliation(s)
- Staton L Wade
- Chromatin and Gene Expression Group, Epigenetics and Stem Cell Biology Laboratory, Department of Health and Human Services
| | - Lee F Langer
- Chromatin and Gene Expression Group, Epigenetics and Stem Cell Biology Laboratory, Department of Health and Human Services
| | - James M Ward
- Integrative Bioinformatics Resource, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, North Carolina, USA
| | - Trevor K Archer
- Chromatin and Gene Expression Group, Epigenetics and Stem Cell Biology Laboratory, Department of Health and Human Services
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46
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Jiang Z, Tang Y, Zhao X, Zhang M, Donovan DM, Tian XC. Knockdown of Brm and Baf170, Components of Chromatin Remodeling Complex, Facilitates Reprogramming of Somatic Cells. Stem Cells Dev 2015; 24:2328-36. [PMID: 26121422 DOI: 10.1089/scd.2015.0069] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The SWI/SNF (SWItch/Sucrose NonFermentable or BAF, Brg/Brahma-associated factors) complexes are epigenetic modifiers of chromatin structure and undergo progressive changes in subunit composition during cellular differentiation. For example, in embryonic stem cells, esBAF contains Brg1 and Baf155, while their homologs, Brm and Baf170, are present in BAF of somatic cells. In this study, we sought to determine whether Brm and Baf170 play any roles in induced pluripotent stem cell (iPSC) reprogramming by using shRNA-mediated knockdown studies in the mouse model. We found that knocking down Brm during early, mid, and late stages (days 3, 6, and 9 after initial iPSC induction) and knocking down Baf170 during late-stage (day 9) reprogramming improve the numbers of iPSC colonies formed. We further showed that inhibition of these somatic BAF components also promotes complete reprogramming of partially reprogrammed somatic cells (pre-iPSCs). Finally, we found that the expression of Brm and Baf170 during reprogramming was regulated by Jak/Stat3 activity. Taken together, these data suggest that inhibiting somatic BAF improves complete reprogramming by facilitating the activation of the pluripotency circuitry.
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Affiliation(s)
- Zongliang Jiang
- 1 Department of Animal Science, Center for Regenerative Biology, University of Connecticut , Storrs, Connecticut
| | - Yong Tang
- 1 Department of Animal Science, Center for Regenerative Biology, University of Connecticut , Storrs, Connecticut
| | - Xueming Zhao
- 1 Department of Animal Science, Center for Regenerative Biology, University of Connecticut , Storrs, Connecticut
| | - Mingyuan Zhang
- 1 Department of Animal Science, Center for Regenerative Biology, University of Connecticut , Storrs, Connecticut
| | - David M Donovan
- 2 Animal Biosciences and Biotechnology Laboratory, Agricultural Research Services , United States Department of Agriculture, Beltsville, Maryland
| | - Xiuchun Cindy Tian
- 1 Department of Animal Science, Center for Regenerative Biology, University of Connecticut , Storrs, Connecticut
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47
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Dang-Nguyen TQ, Torres-Padilla ME. How cells build totipotency and pluripotency: nuclear, chromatin and transcriptional architecture. Curr Opin Cell Biol 2015; 34:9-15. [PMID: 25935759 DOI: 10.1016/j.ceb.2015.04.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Revised: 03/25/2015] [Accepted: 04/14/2015] [Indexed: 01/15/2023]
Abstract
Totipotent and pluripotent cells display different degrees of cellular plasticity. After fertilization, embryonic cells transit naturally from a totipotent to a pluripotent state. Major changes in nuclear architecture, chromatin mobility and gene expression occur during this transition. In particular, nuclear architecture has recently emerged as a potential regulator of heterochromatin formation in the early embryo. Future research should address whether a causal, functional link between nuclear organization and gene regulation is a general theme during reprogramming and the formation of pluripotent cells.
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Affiliation(s)
- Thanh Quang Dang-Nguyen
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, CNRS/INSERM U964, Université de Strasbourg, F-67404 Illkirch, France
| | - Maria-Elena Torres-Padilla
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, CNRS/INSERM U964, Université de Strasbourg, F-67404 Illkirch, France.
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Piazzi M, Williamson A, Lee CF, Pearson S, Lacaud G, Kouskoff V, McCubrey JA, Cocco L, Whetton AD. Quantitative phosphoproteome analysis of embryonic stem cell differentiation toward blood. Oncotarget 2015; 6:10924-39. [PMID: 25890499 PMCID: PMC4484429 DOI: 10.18632/oncotarget.3454] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Accepted: 02/24/2015] [Indexed: 11/25/2022] Open
Abstract
Murine embryonic stem (ES) cells can differentiate in vitro into three germ layers (endodermic, mesodermic, ectodermic). Studies on the differentiation of these cells to specific early differentiation stages has been aided by an ES cell line carrying the Green Fluorescent Protein (GFP) targeted to the Brachyury (Bry) locus which marks mesoderm commitment. Furthermore, expression of the Vascular Endothelial Growth Factor receptor 2 (Flk1) along with Bry defines hemangioblast commitment. Isobaric-tag for relative and absolute quantification (iTRAQ(TM)) and phosphopeptide enrichment coupled to liquid chromatography separation and mass spectrometry allow the study of phosphorylation changes occurring at different stages of ES cell development using Bry and Flk1 expression respectively. We identified and relatively quantified 37 phosphoentities which are modulated during mesoderm-induced ES cells differentiation, comparing epiblast-like, early mesoderm and hemangioblast-enriched cells. Among the proteins differentially phosphorylated toward mesoderm differentiation were: the epigenetic regulator Dnmt3b, the protein kinase GSK3b, the chromatin remodeling factor Smarcc1, the transcription factor Utf1; as well as protein specifically related to stem cell differentiation, as Eomes, Hmga2, Ints1 and Rif1. As most key factors regulating early hematopoietic development have also been implicated in various types of leukemia, understanding the post-translational modifications driving their regulation during normal development could result in a better comprehension of their roles during abnormal hematopoiesis in leukemia.
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Affiliation(s)
- Manuela Piazzi
- Cell Signaling Laboratory, Department of Biomedical Science (DIBINEM), University of Bologna, Italy
| | - Andrew Williamson
- Stem Cell and Leukaemia Proteomics Laboratory, Manchester Academic Health Science Centre, The University of Manchester, Manchester, UK
| | - Chia-Fang Lee
- Stem Cell and Leukaemia Proteomics Laboratory, Manchester Academic Health Science Centre, The University of Manchester, Manchester, UK
| | - Stella Pearson
- Stem Cell Research Group, Manchester Academic Health Science Centre, University of Manchester, Manchester, UK
| | - Georges Lacaud
- Stem Cell Biology Group Paterson Institute for Cancer Research, Manchester Academic Health Science Centre, University of Manchester, Manchester, UK
| | - Valerie Kouskoff
- Stem Cell Research Group, Manchester Academic Health Science Centre, University of Manchester, Manchester, UK
| | - James A. McCubrey
- Department of Microbiology and Immunology, Brody School of Medicine at East Carolina University, Greenville, NC, USA
| | - Lucio Cocco
- Cell Signaling Laboratory, Department of Biomedical Science (DIBINEM), University of Bologna, Italy
| | - Anthony D. Whetton
- Stem Cell and Leukaemia Proteomics Laboratory, Manchester Academic Health Science Centre, The University of Manchester, Manchester, UK
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49
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Alajem A, Biran A, Harikumar A, Sailaja BS, Aaronson Y, Livyatan I, Nissim-Rafinia M, Sommer AG, Mostoslavsky G, Gerbasi VR, Golden DE, Datta A, Sze SK, Meshorer E. Differential association of chromatin proteins identifies BAF60a/SMARCD1 as a regulator of embryonic stem cell differentiation. Cell Rep 2015; 10:2019-31. [PMID: 25818293 DOI: 10.1016/j.celrep.2015.02.064] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Revised: 01/09/2015] [Accepted: 02/25/2015] [Indexed: 11/19/2022] Open
Abstract
Embryonic stem cells (ESCs) possess a distinct chromatin conformation maintained by specialized chromatin proteins. To identify chromatin regulators in ESCs, we developed a simple biochemical assay named D-CAP (differential chromatin-associated proteins), using brief micrococcal nuclease digestion of chromatin, followed by liquid chromatography tandem mass spectrometry (LC-MS/MS). Using D-CAP, we identified several differentially chromatin-associated proteins between undifferentiated and differentiated ESCs, including the chromatin remodeling protein SMARCD1. SMARCD1 depletion in ESCs led to altered chromatin and enhanced endodermal differentiation. Gene expression and chromatin immunoprecipitation sequencing (ChIP-seq) analyses suggested that SMARCD1 is both an activator and a repressor and is enriched at developmental regulators and that its chromatin binding coincides with H3K27me3. SMARCD1 knockdown caused H3K27me3 redistribution and increased H3K4me3 around the transcription start site (TSS). One of the identified SMARCD1 targets was Klf4. In SMARCD1-knockdown clones, KLF4, as well as H3K4me3 at the Klf4 locus, remained high and H3K27me3 was abolished. These results propose a role for SMARCD1 in restricting pluripotency and activating lineage pathways by regulating H3K27 methylation.
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Affiliation(s)
- Adi Alajem
- Department of Genetics, Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Alva Biran
- Department of Genetics, Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Arigela Harikumar
- Department of Genetics, Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Badi Sri Sailaja
- Department of Genetics, Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Yair Aaronson
- Department of Genetics, Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Ilana Livyatan
- Department of Genetics, Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Malka Nissim-Rafinia
- Department of Genetics, Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Andreia Gianotti Sommer
- Section of Gastroenterology, Department of Medicine, Center for Regenerative Medicine (CReM), Boston University School of Medicine, 670 Albany Street, Suite 209, Boston, MA 02118, USA
| | - Gustavo Mostoslavsky
- Section of Gastroenterology, Department of Medicine, Center for Regenerative Medicine (CReM), Boston University School of Medicine, 670 Albany Street, Suite 209, Boston, MA 02118, USA
| | - Vincent R Gerbasi
- Department of Molecular Biosciences, Northwestern University, 2205 Tech Drive, Evanston, IL 60208, USA; Naval Medical Research Center, Silver Spring, MD 20910, USA
| | | | - Arnab Datta
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Singapore
| | - Siu Kwan Sze
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Singapore
| | - Eran Meshorer
- Department of Genetics, Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel; The Edmond and Lily Safra Center for Brain Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
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50
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Sim JCH, White SM, Lockhart PJ. ARID1B-mediated disorders: Mutations and possible mechanisms. Intractable Rare Dis Res 2015; 4:17-23. [PMID: 25674384 PMCID: PMC4322591 DOI: 10.5582/irdr.2014.01021] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2014] [Revised: 12/02/2014] [Accepted: 12/03/2014] [Indexed: 12/22/2022] Open
Abstract
Mutations in the gene encoding AT-rich interactive domain-containing protein 1B (ARID1B) were recently associated with multiple syndromes characterized by developmental delay and intellectual disability, in addition to nonsyndromic intellectual disability. While the majority of ARID1B mutations identified to date are predicted to result in haploinsufficiency, the underlying pathogenic mechanisms have yet to be fully understood. ARID1B is a DNA-binding subunit of the Brahma-associated factor chromatin remodelling complexes, which play a key role in the regulation of gene activity. The function of remodelling complexes can be regulated by their subunit composition, and there is some evidence that ARID1B is a component of the neuron-specific chromatin remodelling complex. This complex is involved in the regulation of stem/progenitor cells exiting the cell cycle and differentiating into postmitotic neurons. Recent research has indicated that alterations in the cell cycle contribute to the underlying pathogenesis of syndromes associated with ARID1B haploinsufficiency in fibroblasts derived from affected individuals. This review describes studies linking ARID1B to neurodevelopmental disorders and it summarizes the function of ARID1B to provide insights into the pathogenic mechanisms underlying ARID1B-mediated disorders. In conclusion, ARID1B is likely to play a key role in neurodevelopment and reduced levels of wild-type protein compromise normal brain development. Additional studies are required to determine the mechanisms by which impaired neural development contributes to the intellectual disability and speech impairment that are consistently observed in individuals with ARID1B haploinsufficiency.
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Affiliation(s)
- Joe C. H. Sim
- Bruce Lefroy Centre for Genetic Health Research, Murdoch Childrens Research Institute, Melbourne, Victoria, Australia
| | - Susan M White
- Bruce Lefroy Centre for Genetic Health Research, Murdoch Childrens Research Institute, Melbourne, Victoria, Australia
- Department of Paediatrics, The University of Melbourne, Melbourne, Victoria, Australia
| | - Paul J. Lockhart
- Bruce Lefroy Centre for Genetic Health Research, Murdoch Childrens Research Institute, Melbourne, Victoria, Australia
- Department of Paediatrics, The University of Melbourne, Melbourne, Victoria, Australia
- Address correspondence to: Dr. Paul J. Lockhart, Murdoch Childrens Research Institute, The Royal Children's Hospital, Flemington Road Parkville, Victoria 3052, Australia. E-mail:
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