51
|
Pursani V, Pethe P, Bashir M, Sampath P, Tanavde V, Bhartiya D. Genetic and Epigenetic Profiling Reveals EZH2-mediated Down Regulation of OCT-4 Involves NR2F2 during Cardiac Differentiation of Human Embryonic Stem Cells. Sci Rep 2017; 7:13051. [PMID: 29026152 PMCID: PMC5638931 DOI: 10.1038/s41598-017-13442-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Accepted: 09/25/2017] [Indexed: 02/07/2023] Open
Abstract
Human embryonic (hES) stem cells are widely used as an in vitro model to understand global genetic and epigenetic changes that occur during early embryonic development. In-house derived hES cells (KIND1) were subjected to directed differentiation into cardiovascular progenitors (D12) and beating cardiomyocytes (D20). Transcriptome profiling of undifferentiated (D0) and differentiated (D12 and 20) cells was undertaken by microarray analysis. ChIP and sequential ChIP were employed to study role of transcription factor NR2F2 during hES cells differentiation. Microarray profiling showed that an alteration of about 1400 and 1900 transcripts occurred on D12 and D20 respectively compared to D0 whereas only 19 genes were altered between D12 and D20. This was found associated with corresponding expression pattern of chromatin remodelers, histone modifiers, miRNAs and lncRNAs marking the formation of progenitors and cardiomyocytes on D12 and D20 respectively. ChIP sequencing and sequential ChIP revealed the binding of NR2F2 with polycomb group member EZH2 and pluripotent factor OCT4 indicating its crucial involvement in cardiac differentiation. The study provides a detailed insight into genetic and epigenetic changes associated with hES cells differentiation into cardiac cells and a role for NR2F2 is deciphered for the first time to down-regulate OCT-4 via EZH2 during cardiac differentiation.
Collapse
Affiliation(s)
- Varsha Pursani
- Stem Cell Biology Department, ICMR- National Institute for Research in Reproductive Health, Mumbai, 400012, India
| | - Prasad Pethe
- Stem Cell Biology Department, ICMR- National Institute for Research in Reproductive Health, Mumbai, 400012, India
- Department of Biological Sciences, Sunandan Divatia School of Science, NMIMS University, Mumbai, 400056, India
| | - Mohsin Bashir
- Institute of Medical Biology, Agency for Science Technology & Research (A*STAR), Singapore, 138648, Singapore
| | - Prabha Sampath
- Institute of Medical Biology, Agency for Science Technology & Research (A*STAR), Singapore, 138648, Singapore
| | - Vivek Tanavde
- Bioinformatics Institute, Agency for Science Technology & Research (A*STAR), Singapore, 138671, Singapore
- Division of Biological & Life Sciences, School of Arts & Sciences, Ahmedabad University, Ahmedabad, 380009, India
| | - Deepa Bhartiya
- Stem Cell Biology Department, ICMR- National Institute for Research in Reproductive Health, Mumbai, 400012, India.
| |
Collapse
|
52
|
Shan Y, Liang Z, Xing Q, Zhang T, Wang B, Tian S, Huang W, Zhang Y, Yao J, Zhu Y, Huang K, Liu Y, Wang X, Chen Q, Zhang J, Shang B, Li S, Shi X, Liao B, Zhang C, Lai K, Zhong X, Shu X, Wang J, Yao H, Chen J, Pei D, Pan G. PRC2 specifies ectoderm lineages and maintains pluripotency in primed but not naïve ESCs. Nat Commun 2017; 8:672. [PMID: 28939884 PMCID: PMC5610324 DOI: 10.1038/s41467-017-00668-4] [Citation(s) in RCA: 79] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Accepted: 07/17/2017] [Indexed: 12/22/2022] Open
Abstract
Polycomb repressive complex 2 and the epigenetic mark that it deposits, H3K27me3, are evolutionarily conserved and play critical roles in development and cancer. However, their roles in cell fate decisions in early embryonic development remain poorly understood. Here we report that knockout of polycomb repressive complex 2 genes in human embryonic stem cells causes pluripotency loss and spontaneous differentiation toward a meso-endoderm fate, owing to de-repression of BMP signalling. Moreover, human embryonic stem cells with deletion of EZH1 or EZH2 fail to differentiate into ectoderm lineages. We further show that polycomb repressive complex 2-deficient mouse embryonic stem cells also release Bmp4 but retain their pluripotency. However, when converted into a primed state, they undergo spontaneous differentiation similar to that of hESCs. In contrast, polycomb repressive complex 2 is dispensable for pluripotency when human embryonic stem cells are converted into the naive state. Our studies reveal both lineage- and pluripotent state-specific roles of polycomb repressive complex 2 in cell fate decisions. Polycomb repressive complex 2 (PRC2) plays an essential role in development by modifying chromatin but what this means at a cellular level is unclear. Here, the authors show that ablation of PRC2 genes in human embryonic stem cells and in mice results in changes in pluripotency and the primed state of cells.
Collapse
Affiliation(s)
- Yongli Shan
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou Medical University, Guangzhou, 511436, China.,University of Chinese Academy of Sciences, Beijing, 100049, China.,Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China
| | - Zechuan Liang
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou Medical University, Guangzhou, 511436, China.,University of Chinese Academy of Sciences, Beijing, 100049, China.,Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China
| | - Qi Xing
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou Medical University, Guangzhou, 511436, China.,Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China.,Institute of Health Sciences, Anhui University, Hefei, 230601, China
| | - Tian Zhang
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou Medical University, Guangzhou, 511436, China.,University of Chinese Academy of Sciences, Beijing, 100049, China.,Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China
| | - Bo Wang
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou Medical University, Guangzhou, 511436, China.,University of Chinese Academy of Sciences, Beijing, 100049, China.,Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China
| | - Shulan Tian
- Department of Health Sciences Research, Division of Biomedical Statistics and Informatics, Mayo Clinic, 200 1st Street SW, Rochester, MN, 55905, USA
| | - Wenhao Huang
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou Medical University, Guangzhou, 511436, China.,Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China
| | - Yanqi Zhang
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou Medical University, Guangzhou, 511436, China.,University of Chinese Academy of Sciences, Beijing, 100049, China.,Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China
| | - Jiao Yao
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou Medical University, Guangzhou, 511436, China.,University of Chinese Academy of Sciences, Beijing, 100049, China.,Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China
| | - Yanling Zhu
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou Medical University, Guangzhou, 511436, China.,University of Chinese Academy of Sciences, Beijing, 100049, China.,Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China
| | - Ke Huang
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou Medical University, Guangzhou, 511436, China.,Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China
| | - Yujian Liu
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou Medical University, Guangzhou, 511436, China.,Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China
| | - Xiaoshan Wang
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou Medical University, Guangzhou, 511436, China.,University of Chinese Academy of Sciences, Beijing, 100049, China.,Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China
| | - Qianyu Chen
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou Medical University, Guangzhou, 511436, China.,Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China
| | - Jian Zhang
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou Medical University, Guangzhou, 511436, China.,Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China
| | - Bizhi Shang
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou Medical University, Guangzhou, 511436, China.,Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China
| | - Shengbiao Li
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou Medical University, Guangzhou, 511436, China.,Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China
| | - Xi Shi
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou Medical University, Guangzhou, 511436, China.,Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China
| | - Baojian Liao
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou Medical University, Guangzhou, 511436, China.,Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China
| | - Cong Zhang
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou Medical University, Guangzhou, 511436, China.,University of Chinese Academy of Sciences, Beijing, 100049, China.,Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China
| | - Keyu Lai
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou Medical University, Guangzhou, 511436, China.,Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China
| | - Xiaofen Zhong
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou Medical University, Guangzhou, 511436, China.,Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China
| | - Xiaodong Shu
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou Medical University, Guangzhou, 511436, China.,Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China
| | - Jinyong Wang
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou Medical University, Guangzhou, 511436, China.,Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China
| | - Hongjie Yao
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou Medical University, Guangzhou, 511436, China.,Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China
| | - Jiekai Chen
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou Medical University, Guangzhou, 511436, China.,Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China
| | - Duanqing Pei
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou Medical University, Guangzhou, 511436, China.,Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China
| | - Guangjin Pan
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou Medical University, Guangzhou, 511436, China. .,Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China.
| |
Collapse
|
53
|
Dupret B, Völkel P, Vennin C, Toillon RA, Le Bourhis X, Angrand PO. The histone lysine methyltransferase Ezh2 is required for maintenance of the intestine integrity and for caudal fin regeneration in zebrafish. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2017; 1860:1079-1093. [PMID: 28887218 DOI: 10.1016/j.bbagrm.2017.08.011] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Revised: 08/16/2017] [Accepted: 08/27/2017] [Indexed: 10/18/2022]
Abstract
The histone lysine methyltransferase EZH2, as part of the Polycomb Repressive Complex 2 (PRC2), mediates H3K27me3 methylation which is involved in gene expression program repression. Through its action, EZH2 controls cell-fate decisions during the development and the differentiation processes. Here, we report the generation and the characterization of an ezh2-deficient zebrafish line. In contrast to its essential role in mouse early development, loss of ezh2 function does not affect zebrafish gastrulation. Ezh2 zebrafish mutants present a normal body plan but die at around 12 dpf with defects in the intestine wall, due to enhanced cell death. Thus, ezh2-deficient zebrafish can initiate differentiation toward the different developmental lineages but fail to maintain the intestinal homeostasis. Expression studies revealed that ezh2 mRNAs are maternally deposited. Then, ezh2 is ubiquitously expressed in the anterior part of the embryos at 24 hpf, but its expression becomes restricted to specific regions at later developmental stages. Pharmacological inhibition of Ezh2 showed that maternal Ezh2 products contribute to early development but are dispensable to body plan formation. In addition, ezh2-deficient mutants fail to properly regenerate their spinal cord after caudal fin transection suggesting that Ezh2 and H3K27me3 methylation might also be involved in the process of regeneration in zebrafish.
Collapse
Affiliation(s)
- Barbara Dupret
- Cell Plasticity & Cancer, Inserm U908/University of Lille, Lille, France
| | - Pamela Völkel
- Cell Plasticity & Cancer, Inserm U908/University of Lille, Lille, France; CNRS, Lille, France
| | - Constance Vennin
- Cell Plasticity & Cancer, Inserm U908/University of Lille, Lille, France; SIRIC ONCOLille, Lille, France
| | | | - Xuefen Le Bourhis
- Cell Plasticity & Cancer, Inserm U908/University of Lille, Lille, France
| | | |
Collapse
|
54
|
Welch JD, Hartemink AJ, Prins JF. MATCHER: manifold alignment reveals correspondence between single cell transcriptome and epigenome dynamics. Genome Biol 2017; 18:138. [PMID: 28738873 PMCID: PMC5525279 DOI: 10.1186/s13059-017-1269-0] [Citation(s) in RCA: 93] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Accepted: 07/05/2017] [Indexed: 12/30/2022] Open
Abstract
Single cell experimental techniques reveal transcriptomic and epigenetic heterogeneity among cells, but how these are related is unclear. We present MATCHER, an approach for integrating multiple types of single cell measurements. MATCHER uses manifold alignment to infer single cell multi-omic profiles from transcriptomic and epigenetic measurements performed on different cells of the same type. Using scM&T-seq and sc-GEM data, we confirm that MATCHER accurately predicts true single cell correlations between DNA methylation and gene expression without using known cell correspondences. MATCHER also reveals new insights into the dynamic interplay between the transcriptome and epigenome in single embryonic stem cells and induced pluripotent stem cells.
Collapse
Affiliation(s)
- Joshua D Welch
- Department of Computer Science, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.,Curriculum in Bioinformatics and Computational Biology, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | | | - Jan F Prins
- Department of Computer Science, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA. .,Curriculum in Bioinformatics and Computational Biology, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
| |
Collapse
|
55
|
Abstract
Methylation and acetylation of histone H3 at lysine 27 (H3K27) regulate chromatin structure and gene expression during early embryo development. While H3K27 acetylation (H3K27ac) is associated with active gene expression, H3K27 methylation (H3K27me) is linked to transcriptional repression. The aim of this study was to assess the profile of H3K27 acetylation and methylation (mono-, di- and trimethyl) during oocyte maturation and early development in vitro of porcine embryos. Oocytes/embryos were fixed at different developmental stages from germinal vesicle to day 8 blastocysts and submitted to an immunocytochemistry protocol to identify the presence and quantify the immunofluorescence intensity of H3K27ac, H3K27me1, H3K27me2 and H3K27me3. A strong fluorescent signal for H3K27ac was observed in all developmental stages. H3K27me1 and H3K27me2 were detected in oocytes, but the fluorescent signal decreased through the cleavage stages and rose again at the blastocyst stage. H3K27me3 was detected in oocytes, in only one pronucleus in zygotes, cleaved-stage embryos and blastocysts. The nuclear fluorescence signal for H3K27me3 increased from the 2-cell stage to 4-cell stage embryos, decreased at the 8-cell and morula stages and increased again in blastocysts. Different patterns of the H3K27me3 mark were observed at the blastocyst stage. Our results suggest that changes in the H3K27 methylation status regulate early porcine embryo development as previously shown in other species.
Collapse
|
56
|
Satthenapalli VR, Lamberts RR, Katare RG. Concise Review: Challenges in Regenerating the Diabetic Heart: A Comprehensive Review. Stem Cells 2017. [PMID: 28639375 DOI: 10.1002/stem.2661] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Stem cell therapy is one of the promising regenerative strategies developed to improve cardiac function in patients with ischemic heart diseases (IHD). However, this approach is limited in IHD patients with diabetes due to a progressive decline in the regenerative capacity of stem cells. This decline is mainly attributed to the metabolic memory incurred by diabetes on stem cell niche and their systemic cues. Understanding the molecular pathways involved in the diabetes-induced deterioration of stem cell function will be critical for developing new cardiac regeneration therapies. In this review, we first discuss the most common molecular alterations occurring in the diabetic stem cells/progenitor cells. Next, we highlight the key signaling pathways that can be dysregulated in a diabetic environment and impair the mobilization of stem/progenitor cells, which is essential for the transplanted/endogenous stem cells to reach the site of injury. We further discuss the possible methods of preconditioning the diabetic cardiac progenitor cell (CPC) with an aim to enrich the availability of efficient stem cells to regenerate the diseased diabetic heart. Finally, we propose new modalities for enriching the diabetic CPC through genetic or tissue engineering that would aid in developing autologous therapeutic strategies, improving the proliferative, angiogenic, and cardiogenic properties of diabetic stem/progenitor cells. Stem Cells 2017;35:2009-2026.
Collapse
Affiliation(s)
- Venkata R Satthenapalli
- Department of Physiology, School of Biomedical Sciences, HeartOtago, University of Otago, Dunedin, New Zealand
| | - Regis R Lamberts
- Department of Physiology, School of Biomedical Sciences, HeartOtago, University of Otago, Dunedin, New Zealand
| | - Rajesh G Katare
- Department of Physiology, School of Biomedical Sciences, HeartOtago, University of Otago, Dunedin, New Zealand
| |
Collapse
|
57
|
Eun SH, Feng L, Cedeno-Rosario L, Gan Q, Wei G, Cui K, Zhao K, Chen X. Polycomb Group Gene E(z) Is Required for Spermatogonial Dedifferentiation in Drosophila Adult Testis. J Mol Biol 2017; 429:2030-2041. [PMID: 28434938 PMCID: PMC5516936 DOI: 10.1016/j.jmb.2017.04.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Revised: 03/30/2017] [Accepted: 04/17/2017] [Indexed: 12/12/2022]
Abstract
Dedifferentiation is an important process to replenish lost stem cells during aging or regeneration after injury to maintain tissue homeostasis. Here, we report that Enhancer of Zeste [E(z)], a component of the Polycomb repression complex 2 (PRC2), is required to maintain a stable pool of germline stem cells (GSCs) within the niche microenvironment. During aging, germ cells with reduced E(z) activity cannot meet that requirement, but the defect arises from neither increased GSC death nor premature differentiation. Instead, we found evidence that the decrease of GSCs upon the inactivation of E(z) in the germline could be attributed to defective dedifferentiation. During recovery from genetically manipulated GSC depletion, E(z) knockdown germ cells also fail to replenish lost GSCs. Taken together, our data suggest that E(z) acts intrinsically in germ cells to activate dedifferentiation and thus replenish lost GSCs during both aging and tissue regeneration.
Collapse
Affiliation(s)
- Suk Ho Eun
- Department of Biology, The Johns Hopkins University, Baltimore, MD 21218, USA
| | - Lijuan Feng
- Department of Biology, The Johns Hopkins University, Baltimore, MD 21218, USA
| | - Luis Cedeno-Rosario
- Department of Biology, The Johns Hopkins University, Baltimore, MD 21218, USA
| | - Qiang Gan
- Department of Biology, The Johns Hopkins University, Baltimore, MD 21218, USA
| | - Gang Wei
- Laboratory of Molecular Immunology, National Heart, Lung and Blood Institute, NIH, Bethesda, MD 20892, USA
| | - Kairong Cui
- Laboratory of Molecular Immunology, National Heart, Lung and Blood Institute, NIH, Bethesda, MD 20892, USA
| | - Keji Zhao
- Laboratory of Molecular Immunology, National Heart, Lung and Blood Institute, NIH, Bethesda, MD 20892, USA
| | - Xin Chen
- Department of Biology, The Johns Hopkins University, Baltimore, MD 21218, USA.
| |
Collapse
|
58
|
Carcamo-Orive I, Hoffman GE, Cundiff P, Beckmann ND, D'Souza SL, Knowles JW, Patel A, Papatsenko D, Abbasi F, Reaven GM, Whalen S, Lee P, Shahbazi M, Henrion MYR, Zhu K, Wang S, Roussos P, Schadt EE, Pandey G, Chang R, Quertermous T, Lemischka I. Analysis of Transcriptional Variability in a Large Human iPSC Library Reveals Genetic and Non-genetic Determinants of Heterogeneity. Cell Stem Cell 2017; 20:518-532.e9. [PMID: 28017796 PMCID: PMC5384872 DOI: 10.1016/j.stem.2016.11.005] [Citation(s) in RCA: 186] [Impact Index Per Article: 26.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Revised: 09/23/2016] [Accepted: 11/02/2016] [Indexed: 12/17/2022]
Abstract
Variability in induced pluripotent stem cell (iPSC) lines remains a concern for disease modeling and regenerative medicine. We have used RNA-sequencing analysis and linear mixed models to examine the sources of gene expression variability in 317 human iPSC lines from 101 individuals. We found that ∼50% of genome-wide expression variability is explained by variation across individuals and identified a set of expression quantitative trait loci that contribute to this variation. These analyses coupled with allele-specific expression show that iPSCs retain a donor-specific gene expression pattern. Network, pathway, and key driver analyses showed that Polycomb targets contribute significantly to the non-genetic variability seen within and across individuals, highlighting this chromatin regulator as a likely source of reprogramming-based variability. Our findings therefore shed light on variation between iPSC lines and illustrate the potential for our dataset and other similar large-scale analyses to identify underlying drivers relevant to iPSC applications.
Collapse
Affiliation(s)
- Ivan Carcamo-Orive
- Department of Medicine and Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Gabriel E Hoffman
- Department of Genetics and Genomic Sciences, Institute of Genomics and Multiscale Biology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Paige Cundiff
- Department of Developmental and Regenerative Biology, Black Family Stem Cell Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Noam D Beckmann
- Department of Genetics and Genomic Sciences, Institute of Genomics and Multiscale Biology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Sunita L D'Souza
- Department of Developmental and Regenerative Biology, Experimental Therapeutics Institute, Black Family Stem Cell Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Joshua W Knowles
- Department of Medicine and Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Achchhe Patel
- Department of Developmental and Regenerative Biology, Black Family Stem Cell Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Dimitri Papatsenko
- Department of Developmental and Regenerative Biology, Black Family Stem Cell Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; Skolkovo Institute of Science and Technology, Nobel Street, Building 3, Moscow 143026, Russia
| | - Fahim Abbasi
- Department of Medicine and Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Gerald M Reaven
- Department of Medicine and Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Sean Whalen
- Gladstone Institutes, University of California, San Francisco, San Francisco, CA 94148, USA
| | - Philip Lee
- Department of Medicine and Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Mohammad Shahbazi
- Department of Medicine and Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Marc Y R Henrion
- Department of Genetics and Genomic Sciences, Institute of Genomics and Multiscale Biology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Kuixi Zhu
- Department of Genetics and Genomic Sciences, Institute of Genomics and Multiscale Biology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Sven Wang
- Department of Genetics and Genomic Sciences, Institute of Genomics and Multiscale Biology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Panos Roussos
- Department of Genetics and Genomic Sciences, Institute of Genomics and Multiscale Biology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; Mental Illness Research, Education, and Clinical Center (VISN 3), James J. Peters VA Medical Center, Bronx, NY 10468, USA
| | - Eric E Schadt
- Department of Genetics and Genomic Sciences, Institute of Genomics and Multiscale Biology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Gaurav Pandey
- Department of Genetics and Genomic Sciences, Institute of Genomics and Multiscale Biology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Rui Chang
- Department of Genetics and Genomic Sciences, Institute of Genomics and Multiscale Biology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA.
| | - Thomas Quertermous
- Department of Medicine and Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA 94305, USA.
| | - Ihor Lemischka
- Department of Developmental and Regenerative Biology, Black Family Stem Cell Institute, 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
| |
Collapse
|
59
|
Olivares AM, Jelcick AS, Reinecke J, Leehy B, Haider A, Morrison MA, Cheng L, Chen DF, DeAngelis MM, Haider NB. Multimodal Regulation Orchestrates Normal and Complex Disease States in the Retina. Sci Rep 2017; 7:690. [PMID: 28386079 PMCID: PMC5429617 DOI: 10.1038/s41598-017-00788-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Accepted: 03/13/2017] [Indexed: 12/20/2022] Open
Abstract
Regulation of biological processes occurs through complex, synergistic mechanisms. In this study, we discovered the synergistic orchestration of multiple mechanisms regulating the normal and diseased state (age related macular degeneration, AMD) in the retina. We uncovered gene networks with overlapping feedback loops that are modulated by nuclear hormone receptors (NHR), miRNAs, and epigenetic factors. We utilized a comprehensive filtering and pathway analysis strategy comparing miRNA and microarray data between three mouse models and human donor eyes (normal and AMD). The mouse models lack key NHRS (Nr2e3, RORA) or epigenetic (Ezh2) factors. Fifty-four total miRNAs were differentially expressed, potentially targeting over 150 genes in 18 major representative networks including angiogenesis, metabolism, and immunity. We identified sixty-eight genes and 5 miRNAS directly regulated by NR2E3 and/or RORA. After a comprehensive analysis, we discovered multimodal regulation by miRNA, NHRs, and epigenetic factors of three miRNAs (miR-466, miR1187, and miR-710) and two genes (Ell2 and Entpd1) that are also associated with AMD. These studies provide insight into the complex, dynamic modulation of gene networks as well as their impact on human disease, and provide novel data for the development of innovative and more effective therapeutics.
Collapse
Affiliation(s)
- A M Olivares
- Schepens Eye Research Institute, Massachusetts Eye and Ear Infirmary, Department of Ophthalmology, Harvard Medical School, Boston, MA, United States of America
| | - A S Jelcick
- Genetics, Cell Biology, and Anatomy, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
| | - J Reinecke
- Genetics, Cell Biology, and Anatomy, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
| | - B Leehy
- Genetics, Cell Biology, and Anatomy, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
| | - A Haider
- Schepens Eye Research Institute, Massachusetts Eye and Ear Infirmary, Department of Ophthalmology, Harvard Medical School, Boston, MA, United States of America
| | - M A Morrison
- Ophthalmology and Visual Sciences, John A. Moran Eye Center, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - L Cheng
- Schepens Eye Research Institute, Massachusetts Eye and Ear Infirmary, Department of Ophthalmology, Harvard Medical School, Boston, MA, United States of America
| | - D F Chen
- Schepens Eye Research Institute, Massachusetts Eye and Ear Infirmary, Department of Ophthalmology, Harvard Medical School, Boston, MA, United States of America
| | - M M DeAngelis
- Ophthalmology and Visual Sciences, John A. Moran Eye Center, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - N B Haider
- Schepens Eye Research Institute, Massachusetts Eye and Ear Infirmary, Department of Ophthalmology, Harvard Medical School, Boston, MA, United States of America.
| |
Collapse
|
60
|
Li J, Wang Z, Hu Y, Cao Y, Ma L. Polycomb Group Proteins RING1A and RING1B Regulate the Vegetative Phase Transition in Arabidopsis. FRONTIERS IN PLANT SCIENCE 2017; 8:867. [PMID: 28596781 PMCID: PMC5443144 DOI: 10.3389/fpls.2017.00867] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Accepted: 05/09/2017] [Indexed: 05/18/2023]
Abstract
Polycomb group (PcG) protein-mediated gene silencing is a major regulatory mechanism in higher eukaryotes that affects gene expression at the transcriptional level. Here, we report that two conserved homologous PcG proteins, RING1A and RING1B (RING1A/B), are required for global H2A monoubiquitination (H2Aub) in Arabidopsis. The mutation of RING1A/B increased the expression of members of the SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL) gene family and caused an early vegetative phase transition. The early vegetative phase transition observed in ring1a ring1b double mutant plants was dependent on an SPL family gene, and the H2Aub status of the chromatin at SPL locus was dependent on RING1A/B. Moreover, mutation in RING1A/B affected the miRNA156a-mediated vegetative phase transition, and RING1A/B and the AGO7-miR390-TAS3 pathway were found to additively regulate this transition in Arabidopsis. Together, our results demonstrate that RING1A/B regulates the vegetative phase transition in Arabidopsis through the repression of SPL family genes.
Collapse
|
61
|
Hosogane M, Funayama R, Shirota M, Nakayama K. Lack of Transcription Triggers H3K27me3 Accumulation in the Gene Body. Cell Rep 2016; 16:696-706. [PMID: 27396330 DOI: 10.1016/j.celrep.2016.06.034] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2015] [Revised: 05/07/2016] [Accepted: 06/05/2016] [Indexed: 10/21/2022] Open
Abstract
Trimethylated H3K27 (H3K27me3) is associated with transcriptional repression, and its abundance in chromatin is frequently altered in cancer. However, it has remained unclear how genomic regions modified by H3K27me3 are specified and formed. We previously showed that downregulation of transcription by oncogenic Ras signaling precedes upregulation of H3K27me3 level. Here, we show that lack of transcription as a result of deletion of the transcription start site of a gene is sufficient to increase H3K27me3 content in the gene body. We further found that histone deacetylation mediates Ras-induced gene silencing and subsequent H3K27me3 accumulation. The H3K27me3 level increased gradually after Ras activation, requiring at least 35 days to achieve saturation. Such maximal accumulation of H3K27me3 was reversed by forced induction of transcription with the dCas9-activator system. Thus, our results indicate that changes in H3K27me3 level, especially in the body of a subset of genes, are triggered by changes in transcriptional activity itself.
Collapse
Affiliation(s)
- Masaki Hosogane
- Department of Cell Proliferation, United Center for Advanced Research and Translational Medicine, Graduate School of Medicine, Tohoku University, 2-1 Seiryo-machi, Aoba-ku, Sendai 980-8575, Japan
| | - Ryo Funayama
- Department of Cell Proliferation, United Center for Advanced Research and Translational Medicine, Graduate School of Medicine, Tohoku University, 2-1 Seiryo-machi, Aoba-ku, Sendai 980-8575, Japan
| | - Matsuyuki Shirota
- Division of Interdisciplinary Medical Sciences, United Center for Advanced Research and Translational Medicine, Graduate School of Medicine, Tohoku University, 2-1 Seiryo-machi, Aoba-ku, Sendai 980-8575, Japan
| | - Keiko Nakayama
- Department of Cell Proliferation, United Center for Advanced Research and Translational Medicine, Graduate School of Medicine, Tohoku University, 2-1 Seiryo-machi, Aoba-ku, Sendai 980-8575, Japan.
| |
Collapse
|
62
|
Polycomb repressive complex 2 regulates skeletal growth by suppressing Wnt and TGF-β signalling. Nat Commun 2016; 7:12047. [PMID: 27329220 PMCID: PMC4917962 DOI: 10.1038/ncomms12047] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Accepted: 05/24/2016] [Indexed: 01/06/2023] Open
Abstract
Polycomb repressive complex 2 (PRC2) controls maintenance and lineage determination of stem cells by suppressing genes that regulate cellular differentiation and tissue development. However, the role of PRC2 in lineage-committed somatic cells is mostly unknown. Here we show that Eed deficiency in chondrocytes causes severe kyphosis and a growth defect with decreased chondrocyte proliferation, accelerated hypertrophic differentiation and cell death with reduced Hif1a expression. Eed deficiency also causes induction of multiple signalling pathways in chondrocytes. Wnt signalling overactivation is responsible for the accelerated hypertrophic differentiation and kyphosis, whereas the overactivation of TGF-β signalling is responsible for the reduced proliferation and growth defect. Thus, our study demonstrates that PRC2 has an important regulatory role in lineage-committed tissue cells by suppressing overactivation of multiple signalling pathways. Eed is a polycomb repressive complex 2 component involved in stem cell lineage determination, but little is known about its role in lineage committed cells. Here the authors show that chondrocyte-specific Eed KO mice have skeletal growth defects related to induction of Wnt and TGF-β signalling.
Collapse
|
63
|
Mahmoud F, Shields B, Makhoul I, Hutchins LF, Shalin SC, Tackett AJ. Role of EZH2 histone methyltrasferase in melanoma progression and metastasis. Cancer Biol Ther 2016; 17:579-91. [PMID: 27105109 PMCID: PMC4990393 DOI: 10.1080/15384047.2016.1167291] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Revised: 02/25/2016] [Accepted: 03/13/2016] [Indexed: 02/07/2023] Open
Abstract
There is accumulating evidence that the histone methyltransferase enhancer of zeste homolog 2 (EZH2), the main component of the polycomb-repressive complex 2 (PRC2), is involved in melanoma progression and metastasis. Novel drugs that target and reverse such epigenetic changes may find a way into the management of patients with advanced melanoma. We provide a comprehensive up-to-date review of the role and biology of EZH2 on gene transcription, senescence/apoptosis, melanoma microenvironment, melanocyte stem cells, the immune system, and micro RNA. Furthermore, we discuss EZH2 inhibitors as potential anti-cancer therapy.
Collapse
Affiliation(s)
- Fade Mahmoud
- Department of Internal Medicine, Division of Hematology/Oncology, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - Bradley Shields
- Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - Issam Makhoul
- Department of Internal Medicine, Division of Hematology/Oncology, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - Laura F. Hutchins
- Department of Internal Medicine, Division of Hematology/Oncology, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - Sara C. Shalin
- Departments of Pathology and Dermatology, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - Alan J. Tackett
- Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| |
Collapse
|
64
|
Aguilar R, Bustos FJ, Saez M, Rojas A, Allende ML, van Wijnen AJ, van Zundert B, Montecino M. Polycomb PRC2 complex mediates epigenetic silencing of a critical osteogenic master regulator in the hippocampus. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2016; 1859:1043-55. [PMID: 27216774 DOI: 10.1016/j.bbagrm.2016.05.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2015] [Revised: 05/18/2016] [Accepted: 05/19/2016] [Indexed: 12/12/2022]
Abstract
During hippocampal neuron differentiation, the expression of critical inducers of non-neuronal cell lineages must be efficiently silenced. Runx2 transcription factor is the master regulator of mesenchymal cells responsible for intramembranous osteoblast differentiation and formation of the craniofacial bone tissue that surrounds and protects the central nervous system (CNS) in mammalian embryos. The molecular mechanisms that mediate silencing of the Runx2 gene and its downstream target osteogenic-related genes in neuronal cells have not been explored. Here, we assess the epigenetic mechanisms that mediate silencing of osteoblast-specific genes in CNS neurons. In particular, we address the contribution of histone epigenetic marks and histone modifiers on the silencing of the Runx2/p57 bone-related isoform in rat hippocampal tissues at embryonic to adult stages. Our results indicate enrichment of repressive chromatin histone marks and of the Polycomb PRC2 complex at the Runx2/p57 promoter region. Knockdown of PRC2 H3K27-methyltransferases Ezh2 and Ezh1, or forced expression of the Trithorax/COMPASS subunit Wdr5 activates Runx2/p57 mRNA expression in both immature and mature hippocampal cells. Together these results indicate that complementary epigenetic mechanisms progressively and efficiently silence critical osteoblastic genes during hippocampal neuron differentiation.
Collapse
Affiliation(s)
- Rodrigo Aguilar
- Center for Biomedical Research, Universidad Andres Bello, Santiago 8370146, Chile; FONDAP Center for Genome Regulation, Faculty of Biological Sciences and Faculty of Medicine, Universidad Andres Bello, Santiago 8370146, Chile
| | - Fernando J Bustos
- Center for Biomedical Research, Universidad Andres Bello, Santiago 8370146, Chile; FONDAP Center for Genome Regulation, Faculty of Biological Sciences and Faculty of Medicine, Universidad Andres Bello, Santiago 8370146, Chile
| | - Mauricio Saez
- Center for Biomedical Research, Universidad Andres Bello, Santiago 8370146, Chile; FONDAP Center for Genome Regulation, Faculty of Biological Sciences and Faculty of Medicine, Universidad Andres Bello, Santiago 8370146, Chile
| | - Adriana Rojas
- Center for Biomedical Research, Universidad Andres Bello, Santiago 8370146, Chile; FONDAP Center for Genome Regulation, Faculty of Biological Sciences and Faculty of Medicine, Universidad Andres Bello, Santiago 8370146, Chile
| | - Miguel L Allende
- FONDAP Center for Genome Regulation, Faculty of Biological Sciences and Faculty of Medicine, Universidad Andres Bello, Santiago 8370146, Chile; Department of Biology, Faculty of Sciences, Universidad de Chile, Santiago 7800003, Chile
| | | | - Brigitte van Zundert
- Center for Biomedical Research, Universidad Andres Bello, Santiago 8370146, Chile
| | - Martin Montecino
- Center for Biomedical Research, Universidad Andres Bello, Santiago 8370146, Chile; FONDAP Center for Genome Regulation, Faculty of Biological Sciences and Faculty of Medicine, Universidad Andres Bello, Santiago 8370146, Chile.
| |
Collapse
|
65
|
Marchesi I, Bagella L. Targeting Enhancer of Zeste Homolog 2 as a promising strategy for cancer treatment. World J Clin Oncol 2016; 7:135-148. [PMID: 27081636 PMCID: PMC4826959 DOI: 10.5306/wjco.v7.i2.135] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2015] [Revised: 11/20/2015] [Accepted: 02/16/2016] [Indexed: 02/06/2023] Open
Abstract
Polycomb group proteins represent a global silencing system involved in development regulation. In specific, they regulate the transition from proliferation to differentiation, contributing to stem-cell maintenance and inhibiting an inappropriate activation of differentiation programs. Enhancer of Zeste Homolog 2 (EZH2) is the catalytic subunit of Polycomb repressive complex 2, which induces transcriptional inhibition through the tri-methylation of histone H3, an epigenetic change associated with gene silencing. EZH2 expression is high in precursor cells while its level decreases in differentiated cells. EZH2 is upregulated in various cancers with high levels associated with metastatic cancer and poor prognosis. Indeed, aberrant expression of EZH2 causes the inhibition of several tumor suppressors and differentiation genes, resulting in an uncontrolled proliferation and tumor formation. This editorial explores the role of Polycomb repressive complex 2 in cancer, focusing in particular on EZH2. The canonical function of EZH2 in gene silencing, the non-canonical activities as the methylation of other proteins and the role in gene transcriptional activation, were summarized. Moreover, mutations of EZH2, responsible for an increased methyltransferase activity in cancer, were recapitulated. Finally, various drugs able to inhibit EZH2 with different mechanism were described, specifically underscoring the effects in several cancers, in order to clarify the role of EZH2 and understand if EZH2 blockade could be a new strategy for developing specific therapies or a way to increase sensitivity of cancer cells to standard therapies.
Collapse
|
66
|
Dauber KL, Perdigoto CN, Valdes VJ, Santoriello FJ, Cohen I, Ezhkova E. Dissecting the Roles of Polycomb Repressive Complex 2 Subunits in the Control of Skin Development. J Invest Dermatol 2016; 136:1647-1655. [PMID: 26994968 DOI: 10.1016/j.jid.2016.02.809] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Revised: 02/23/2016] [Accepted: 02/29/2016] [Indexed: 12/28/2022]
Abstract
Polycomb repressive complex 2 (PRC2) is an essential regulator of cell physiology. Although there have been numerous studies on PRC2 function in somatic tissue development and stem cell control, these have focused on the loss of a single PRC2 subunit. Recent studies, however, have shown that PRC2 subunits may function independently of the PRC2 complex. To investigate the function of PRC2 in the control of skin development, we generated and analyzed three conditional knockout mouse lines, in which the essential PRC2 subunits embryonic ectoderm development (EED), suppressor of zeste 12 homolog (Suz12), and enhancer of zeste homologs 1 and 2 (Ezh1/2) are conditionally ablated in the embryonic epidermal progenitors that give rise to the epidermis, hair follicles, and Merkel cells. Our studies showed that the observed loss-of-function phenotypes are shared between the three knockouts, indicating that in the skin epithelium, EED, Suz12, and Ezh1/2 function largely as subunits of the PRC2 complex. Interestingly, the absence of PRC2 results in dramatically different phenotypes across the different skin lineages: premature acquisition of a functional epidermal barrier, formation of ectopic Merkel cells, and defective postnatal development of hair follicles. The strikingly different roles of PRC2 in the formation of three lineages exemplify the complex outcomes that the lack of PRC2 can have in a somatic stem cell system.
Collapse
Affiliation(s)
- Katherine L Dauber
- Black Family Stem Cell Institute, Department of Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Carolina N Perdigoto
- Black Family Stem Cell Institute, Department of Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Victor J Valdes
- Black Family Stem Cell Institute, Department of Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Francis J Santoriello
- Black Family Stem Cell Institute, Department of Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Idan Cohen
- Black Family Stem Cell Institute, Department of Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Elena Ezhkova
- Black Family Stem Cell Institute, Department of Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, New York, USA.
| |
Collapse
|
67
|
O'Leary VB, Ovsepian SV, Carrascosa LG, Buske FA, Radulovic V, Niyazi M, Moertl S, Trau M, Atkinson MJ, Anastasov N. PARTICLE, a Triplex-Forming Long ncRNA, Regulates Locus-Specific Methylation in Response to Low-Dose Irradiation. Cell Rep 2016; 11:474-85. [PMID: 25900080 DOI: 10.1016/j.celrep.2015.03.043] [Citation(s) in RCA: 162] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2014] [Revised: 01/31/2015] [Accepted: 03/16/2015] [Indexed: 12/13/2022] Open
Abstract
Exposure to low-dose irradiation causes transiently elevated expression of the long ncRNA PARTICLE (gene PARTICLE, promoter of MAT2A-antisense radiation-induced circulating lncRNA). PARTICLE affords both a cytosolic scaffold for the tumor suppressor methionine adenosyltransferase (MAT2A) and a nuclear genetic platform for transcriptional repression. In situ hybridization discloses that PARTICLE and MAT2A associate together following irradiation. Bromouridine tracing and presence in exosomes indicate intercellular transport, and this is supported by ex vivo data from radiotherapy-treated patients. Surface plasmon resonance indicates that PARTICLE forms a DNA-lncRNA triplex upstream of a MAT2A promoter CpG island. We show that PARTICLE represses MAT2A via methylation and demonstrate that the radiation-induced PARTICLE interacts with the transcription-repressive complex proteins G9a and SUZ12 (subunit of PRC2). The interplay of PARTICLE with MAT2A implicates this lncRNA in intercellular communication and as a recruitment platform for gene-silencing machineries through triplex formation in response to irradiation.
Collapse
|
68
|
H2A.Z.1 Monoubiquitylation Antagonizes BRD2 to Maintain Poised Chromatin in ESCs. Cell Rep 2016; 14:1142-1155. [PMID: 26804911 DOI: 10.1016/j.celrep.2015.12.100] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2015] [Revised: 10/16/2015] [Accepted: 12/22/2015] [Indexed: 12/13/2022] Open
Abstract
Histone variant H2A.Z occupies the promoters of active and poised, bivalent genes in embryonic stem cells (ESCs) to regulate developmental programs, yet how it contributes to these contrasting states is poorly understood. Here, we investigate the function of H2A.Z.1 monoubiquitylation (H2A.Z.1ub) by mutation of the PRC1 target residues (H2A.Z.1(K3R3)). We show that H2A.Z.1(K3R3) is properly incorporated at target promoters in murine ESCs (mESCs), but loss of monoubiquitylation leads to de-repression of bivalent genes, loss of Polycomb binding, and faulty lineage commitment. Using quantitative proteomics, we find that tandem bromodomain proteins, including the BET family member BRD2, are enriched in H2A.Z.1 chromatin. We further show that BRD2 is gained at de-repressed promoters in H2A.Z.1(K3R3) mESCs, whereas BRD2 inhibition restores gene silencing at these sites. Together, our study reveals an antagonistic relationship between H2A.Z.1ub and BRD2 to regulate the transcriptional balance at bivalent genes to enable proper execution of developmental programs.
Collapse
|
69
|
Gu Y, Jones AE, Yang W, Liu S, Dai Q, Liu Y, Swindle CS, Zhou D, Zhang Z, Ryan TM, Townes TM, Klug CA, Chen D, Wang H. The histone H2A deubiquitinase Usp16 regulates hematopoiesis and hematopoietic stem cell function. Proc Natl Acad Sci U S A 2016; 113. [DOI: www.pnas.org/cgi/doi/10.1073/pnas.1517041113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2023] Open
Abstract
Significance
Polycomb repressive complex 1 (PRC1) represents an important epigenetic regulator, which exerts its effect on gene expression via histone H2A ubiquitination (ubH2A). We developed a conditional
Usp16
knockout mouse model and demonstrated that
Usp16
is indispensable for hematopoiesis and hematopoietic stem cell (HSC) lineage commitment. We identified Usp16 to be a H2A deubiquitinase that counterbalances the PRC1 ubiquitin ligase to control ubH2A level in the hematopoietic system. Conditional
Usp16
deletion led to altered expression of many regulators of chromatin organization and hematopoiesis. In addition, Usp16 maintains normal HSC cell cycle status via repressing the expression of
Cdkn1a
, which encodes p21cip1, an inhibitor of cell cycle entry. This study provides novel insights into the epigenetic mechanism that regulates hematopoiesis and HSC function.
Collapse
Affiliation(s)
- Yue Gu
- Department of Biochemistry and Molecular Genetics, Stem Cell Institute, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Amanda E. Jones
- Department of Biochemistry and Molecular Genetics, Stem Cell Institute, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Wei Yang
- Department of Biochemistry and Molecular Genetics, Stem Cell Institute, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Shanrun Liu
- Department of Biochemistry and Molecular Genetics, Stem Cell Institute, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Qian Dai
- Department of Pathology, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Yudong Liu
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL 35294
| | - C. Scott Swindle
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Dewang Zhou
- Department of Biochemistry and Molecular Genetics, Stem Cell Institute, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Zhuo Zhang
- Department of Biochemistry and Molecular Genetics, Stem Cell Institute, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Thomas M. Ryan
- Department of Biochemistry and Molecular Genetics, Stem Cell Institute, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Tim M. Townes
- Department of Biochemistry and Molecular Genetics, Stem Cell Institute, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Christopher A. Klug
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Dongquan Chen
- Division of Preventive Medicine, Comprehensive Cancer Center, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Hengbin Wang
- Department of Biochemistry and Molecular Genetics, Stem Cell Institute, University of Alabama at Birmingham, Birmingham, AL 35294
| |
Collapse
|
70
|
Cohen I, Ezhkova E. Cbx4: A new guardian of p63's domain of epidermal control. J Cell Biol 2016; 212:9-11. [PMID: 26711501 PMCID: PMC4700485 DOI: 10.1083/jcb.201512032] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Accepted: 12/16/2015] [Indexed: 01/02/2023] Open
Abstract
Epigenetic regulators are essential for cell lineage choices during development. In this issue, Mardaryev et al. (2016. J. Cell Biol. http://dx.doi.org/10.1083/jcb.201506065) show that Polycomb subunit Cbx4 acts downstream of transcriptional regulator p63 to maintain epidermal progenitor identity and proliferation in the developing epidermis via Polycomb-dependent and -independent SUMO E3 ligase activities.
Collapse
Affiliation(s)
- Idan Cohen
- Department of Developmental and Regenerative Biology, Black Family Stem Cell Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Elena Ezhkova
- Department of Developmental and Regenerative Biology, Black Family Stem Cell Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| |
Collapse
|
71
|
The histone H2A deubiquitinase Usp16 regulates hematopoiesis and hematopoietic stem cell function. Proc Natl Acad Sci U S A 2015; 113:E51-60. [PMID: 26699484 DOI: 10.1073/pnas.1517041113] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Epigenetic mechanisms play important regulatory roles in hematopoiesis and hematopoietic stem cell (HSC) function. Subunits of polycomb repressive complex 1 (PRC1), the major histone H2A ubiquitin ligase, are critical for both normal and pathological hematopoiesis; however, it is unclear which of the several counteracting H2A deubiquitinases functions along with PRC1 to control H2A ubiquitination (ubH2A) level and regulates hematopoiesis in vivo. Here we investigated the function of Usp16 in mouse hematopoiesis. Conditional deletion of Usp16 in bone marrow resulted in a significant increase of global ubH2A level and lethality. Usp16 deletion did not change HSC number but was associated with a dramatic reduction of mature and progenitor cell populations, revealing a role in governing HSC lineage commitment. ChIP- and RNA-sequencing studies in HSC and progenitor cells revealed that Usp16 bound to many important hematopoietic regulators and that Usp16 deletion altered the expression of genes in transcription/chromosome organization, immune response, hematopoietic/lymphoid organ development, and myeloid/leukocyte differentiation. The altered gene expression was partly rescued by knockdown of PRC1 subunits, suggesting that Usp16 and PRC1 counterbalance each other to regulate cellular ubH2A level and gene expression in the hematopoietic system. We further discovered that knocking down Cdkn1a (p21cip1), a Usp16 target and regulated gene, rescued the altered cell cycle profile and differentiation defect of Usp16-deleted HSCs. Collectively, these studies identified Usp16 as one of the histone H2A deubiquitinases, which coordinates with the H2A ubiquitin ligase PRC1 to regulate hematopoiesis, and revealed cell cycle regulation by Usp16 as key for HSC differentiation.
Collapse
|
72
|
Chen HC, Huang HY, Chen YL, Lee KD, Chu YR, Lin PY, Hsu CC, Chu PY, Huang THM, Hsiao SH, Leu YW. Methylation of the Tumor Suppressor Genes HIC1 and RassF1A Clusters Independently From the Methylation of Polycomb Target Genes in Colon Cancer. Ann Surg Oncol 2015; 24:578-585. [PMID: 26671036 DOI: 10.1245/s10434-015-5024-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Indexed: 12/31/2022]
Abstract
BACKGROUND Methylation changes within tumor suppressor (TS) genes or polycomb group target (PcG) genes alter cell fates. Chromatin associated with PcG targets is bivalent in stem cells, while TS genes are not normally bivalent. PcG target methylation changes have been identified in tumor stem cells, and abnormal methylation is found in TS genes in cancers. If the epigenetic states of genes influence DNA methylation, then methylation of PcG targets and TS genes may evolve differently during cancer development. More importantly, methylation changes may be part of a sequence in tumorigenesis. METHODS Chromatin and methylation states of 4 PcG targets and 2 TS genes were determined in colon cancer cells. The methylation states were also detected in 100 pairs of colon cancer samples. Principle component analysis (PCA) was used to reveal whether TS methylation or PcG methylation was the main methylation change associated with colon cancers. RESULTS Chromatin and methylation states differ in colon cancer cell lines. The methylation states within PcG targets clustered independently from the methylation states in TS genes, a finding we previously reported in liver cancers. PCA in colon cancers revealed the strongest association with methylation changes in 2 TS genes, HIC1 and RassF1A. Loss of HIC1 methylation correlated with decreased tumor migration. CONCLUSIONS PcG and TS methylation states cluster independently from each other. The deduced principle component correlated better with TS methylation than PcG methylation in colon cancer. Abnormal methylation changes may represent a sequential biomarker profile to identify developing colon cancer.
Collapse
Affiliation(s)
- Hong-Chang Chen
- Division of Colorectal Surgery, Department of Surgery, Changhua Christian Hospital, Changhua, Taiwan
| | - Hsuan-Yuan Huang
- Division of Colorectal Surgery, Department of Surgery, Changhua Christian Hospital, Changhua, Taiwan
| | - Yao-Li Chen
- Transplant Medicine & Surgery Research Centre, Changhua Christian Hospital, Changhua, Taiwan.,School of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Kuan-Der Lee
- Department of Hematology and Oncology, Chang Gung Memorial Hospital, Chiayi, Chang Gung University College of Medicine, Taoyuan, Taiwan.,Chang Gung Institute of Technology, Taoyuan, Taiwan
| | - Yi-Ru Chu
- Department of Hematology and Oncology, Chang Gung Memorial Hospital, Chiayi, Chang Gung University College of Medicine, Taoyuan, Taiwan.,Chang Gung Institute of Technology, Taoyuan, Taiwan.,Department of Life Science, Human Epigenomics Center, Institute of Molecular Biology and Institute of Biomedical Science, National Chung Cheng University, Chia-Yi, Taiwan
| | - Ping-Yi Lin
- Transplant Medicine & Surgery Research Centre, Changhua Christian Hospital, Changhua, Taiwan
| | - Chia-Chen Hsu
- Department of Life Science, Human Epigenomics Center, Institute of Molecular Biology and Institute of Biomedical Science, National Chung Cheng University, Chia-Yi, Taiwan
| | - Pei-Yi Chu
- Department of Pathology, Show Chwan Memorial Hospital, Changhua, Taiwan
| | - Tim H-M Huang
- Department of Molecular Medicine and Institute of Biotechnology, School of Medicine, Cancer Therapy and Research Center, The University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Shu-Huei Hsiao
- Department of Life Science, Human Epigenomics Center, Institute of Molecular Biology and Institute of Biomedical Science, National Chung Cheng University, Chia-Yi, Taiwan
| | - Yu-Wei Leu
- Department of Life Science, Human Epigenomics Center, Institute of Molecular Biology and Institute of Biomedical Science, National Chung Cheng University, Chia-Yi, Taiwan.
| |
Collapse
|
73
|
Ezh2 regulates differentiation and function of natural killer cells through histone methyltransferase activity. Proc Natl Acad Sci U S A 2015; 112:15988-93. [PMID: 26668377 DOI: 10.1073/pnas.1521740112] [Citation(s) in RCA: 128] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Changes of histone modification status at critical lineage-specifying gene loci in multipotent precursors can influence cell fate commitment. The contribution of these epigenetic mechanisms to natural killer (NK) cell lineage determination from common lymphoid precursors is not understood. Here we investigate the impact of histone methylation repressive marks (H3 Lys27 trimethylation; H3K27(me3)) on early NK cell differentiation. We demonstrate that selective loss of the histone-lysine N-methyltransferase Ezh2 (enhancer of zeste homolog 2) or inhibition of its enzymatic activity with small molecules unexpectedly increased generation of the IL-15 receptor (IL-15R) CD122(+) NK precursors and mature NK progeny from both mouse and human hematopoietic stem and progenitor cells. Mechanistic studies revealed that enhanced NK cell expansion and cytotoxicity against tumor cells were associated with up-regulation of CD122 and the C-type lectin receptor NKG2D. Moreover, NKG2D deficiency diminished the positive effects of Ezh2 inhibitors on NK cell commitment. Identification of the contribution of Ezh2 to NK lineage specification and function reveals an epigenetic-based mechanism that regulates NK cell development and provides insight into the clinical application of Ezh2 inhibitors in NK-based cancer immunotherapies.
Collapse
|
74
|
Semrau S, van Oudenaarden A. Studying Lineage Decision-Making In Vitro: Emerging Concepts and Novel Tools. Annu Rev Cell Dev Biol 2015; 31:317-45. [DOI: 10.1146/annurev-cellbio-100814-125300] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
| | - Alexander van Oudenaarden
- Hubrecht Institute, 3584 CT Utrecht, The Netherlands;
- University Medical Center Utrecht, Cancer Genomics Netherlands, 3584 CG Utrecht, The Netherlands
| |
Collapse
|
75
|
Ezh2 is involved in radial neuronal migration through regulating Reelin expression in cerebral cortex. Sci Rep 2015; 5:15484. [PMID: 26499080 PMCID: PMC4620455 DOI: 10.1038/srep15484] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Accepted: 09/28/2015] [Indexed: 01/29/2023] Open
Abstract
Radial migration of pyramidal neurons is an important event during the development of cerebral cortex. Neurons experience series of morphological and directional transitions to get to their final laminar positions. Here we report that the histone methyltransferase enhancer of zest homolog 2 (Ezh2) is involved in the regulation of cortical radial migration. We show that Ezh2 knockdown leads to disturbed neuronal orientation, which results in the impairment of radial migration. Further results reveal that this migration deficiency may be due to the derepression of Reelin transcription in the migrating neurons. Our study provides evidence that epigenetic regulation of Reelin by Ezh2 maintains appropriate Reelin expression pattern to fulfill proper orientation of migrating neurons.
Collapse
|
76
|
Wang W, Qin JJ, Voruganti S, Nag S, Zhou J, Zhang R. Polycomb Group (PcG) Proteins and Human Cancers: Multifaceted Functions and Therapeutic Implications. Med Res Rev 2015; 35:1220-67. [PMID: 26227500 DOI: 10.1002/med.21358] [Citation(s) in RCA: 81] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Polycomb group (PcG) proteins are transcriptional repressors that regulate several crucial developmental and physiological processes in the cell. More recently, they have been found to play important roles in human carcinogenesis and cancer development and progression. The deregulation and dysfunction of PcG proteins often lead to blocking or inappropriate activation of developmental pathways, enhancing cellular proliferation, inhibiting apoptosis, and increasing the cancer stem cell population. Genetic and molecular investigations of PcG proteins have long been focused on their PcG functions. However, PcG proteins have recently been shown to exert non-classical-Pc-functions, contributing to the regulation of diverse cellular functions. We and others have demonstrated that PcG proteins regulate the expression and function of several oncogenes and tumor suppressor genes in a PcG-independent manner, and PcG proteins are associated with the survival of patients with cancer. In this review, we summarize the recent advances in the research on PcG proteins, including both the Pc-repressive and non-classical-Pc-functions. We specifically focus on the mechanisms by which PcG proteins play roles in cancer initiation, development, and progression. Finally, we discuss the potential value of PcG proteins as molecular biomarkers for the diagnosis and prognosis of cancer, and as molecular targets for cancer therapy.
Collapse
Affiliation(s)
- Wei Wang
- Department of Pharmaceutical Sciences, School of Pharmacy, Texas Tech University Health Sciences Center, Amarillo, TX, 79106.,Center for Cancer Biology and Therapy, School of Pharmacy, Texas Tech University Health Sciences Center, Amarillo, TX, 79106
| | - Jiang-Jiang Qin
- Department of Pharmaceutical Sciences, School of Pharmacy, Texas Tech University Health Sciences Center, Amarillo, TX, 79106
| | - Sukesh Voruganti
- Department of Pharmaceutical Sciences, School of Pharmacy, Texas Tech University Health Sciences Center, Amarillo, TX, 79106
| | - Subhasree Nag
- Department of Pharmaceutical Sciences, School of Pharmacy, Texas Tech University Health Sciences Center, Amarillo, TX, 79106
| | - Jianwei Zhou
- Department of Molecular Cell Biology and Toxicology, Cancer Center, School of Public Health, Nanjing Medical University, Nanjing, 210029, P. R. China
| | - Ruiwen Zhang
- Department of Pharmaceutical Sciences, School of Pharmacy, Texas Tech University Health Sciences Center, Amarillo, TX, 79106.,Center for Cancer Biology and Therapy, School of Pharmacy, Texas Tech University Health Sciences Center, Amarillo, TX, 79106
| |
Collapse
|
77
|
Pethe P, Pursani V, Bhartiya D. Lineage specific expression of Polycomb Group Proteins in human embryonic stem cells in vitro. Cell Biol Int 2015; 39:600-10. [PMID: 25572667 DOI: 10.1002/cbin.10431] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2014] [Accepted: 12/26/2014] [Indexed: 02/05/2023]
Abstract
Human embryonic (hES) stem cells are an excellent model to study lineage specification and differentiation into various cell types. Differentiation necessitates repression of specific genes not required for a particular lineage. Polycomb Group (PcG) proteins are key histone modifiers, whose primary function is gene repression. PcG proteins form complexes called Polycomb Repressive Complexes (PRCs), which catalyze histone modifications such as H2AK119ub1, H3K27me3, and H3K9me3. PcG proteins play a crucial role during differentiation of stem cells. The expression of PcG transcripts during differentiation of hES cells into endoderm, mesoderm, and ectoderm lineage is yet to be shown. In-house derived hES cell line KIND1 was differentiated into endoderm, mesoderm, and ectoderm lineages; followed by characterization using RT-PCR for HNF4A, CDX2, MEF2C, TBX5, SOX1, and MAP2. qRT-PCR and western blotting was performed to compare expression of PcG transcripts and proteins across all the three lineages. We observed that cells differentiated into endoderm showed upregulation of RING1B, BMI1, EZH2, and EED transcripts. Mesoderm differentiation was characterized by significant downregulation of all PcG transcripts during later stages. BMI1 and RING1B were upregulated while EZH2, SUZ12, and EED remained low during ectoderm differentiation. Western blotting also showed distinct expression of BMI1 and EZH2 during differentiation into three germ layers. Our study shows that hES cells differentiating into endoderm, mesoderm, and ectoderm lineages show distinct PcG expression profile at transcript and protein level.
Collapse
Affiliation(s)
- Prasad Pethe
- Stem Cell Biology Department, National Institute for Research in Reproductive Health (NIRRH), Jehangir Merwanji Street, Parel, Mumbai, 400012, India
| | | | | |
Collapse
|
78
|
Li J, Jiang D. The role of epigenomics in the neurodegeneration of ataxia-telangiectasia. Epigenomics 2015; 7:137-41. [DOI: 10.2217/epi.14.81] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Affiliation(s)
- Jiali Li
- Key Laboratory of Animal Models & Human Disease Mechanisms of the Chinese Academy of Sciences & Yunnan Province, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650223, China
| | - Dewei Jiang
- Key Laboratory of Animal Models & Human Disease Mechanisms of the Chinese Academy of Sciences & Yunnan Province, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650223, China
| |
Collapse
|
79
|
Alexander JM, Hota SK, He D, Thomas S, Ho L, Pennacchio LA, Bruneau BG. Brg1 modulates enhancer activation in mesoderm lineage commitment. Development 2015; 142:1418-30. [PMID: 25813539 PMCID: PMC4392595 DOI: 10.1242/dev.109496] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2014] [Accepted: 02/27/2015] [Indexed: 12/28/2022]
Abstract
The interplay between different levels of gene regulation in modulating developmental transcriptional programs, such as histone modifications and chromatin remodeling, is not well understood. Here, we show that the chromatin remodeling factor Brg1 is required for enhancer activation in mesoderm induction. In an embryonic stem cell-based directed differentiation assay, the absence of Brg1 results in a failure of cardiomyocyte differentiation and broad deregulation of lineage-specific gene expression during mesoderm induction. We find that Brg1 co-localizes with H3K27ac at distal enhancers and is required for robust H3K27 acetylation at distal enhancers that are activated during mesoderm induction. Brg1 is also required to maintain Polycomb-mediated repression of non-mesodermal developmental regulators, suggesting cooperativity between Brg1 and Polycomb complexes. Thus, Brg1 is essential for modulating active and repressive chromatin states during mesoderm lineage commitment, in particular the activation of developmentally important enhancers. These findings demonstrate interplay between chromatin remodeling complexes and histone modifications that, together, ensure robust and broad gene regulation during crucial lineage commitment decisions. SUMMARY: The chromatin remodeling factor Brg1 is essential for mesoderm induction and, by modulating active and repressive chromatin states, is involved in promoting the activation of dynamic enhancers.
Collapse
Affiliation(s)
- Jeffrey M Alexander
- 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
| | - 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
| | - Daniel He
- 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
| | - Sean Thomas
- 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
| | - Lena Ho
- Institute of Medical Biology, A*STAR, Singapore 138648
| | - Len A Pennacchio
- Genomics Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA United States Department of Energy, Joint Genome Institute, Walnut Creek, CA 94598, 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
| |
Collapse
|
80
|
HEB associates with PRC2 and SMAD2/3 to regulate developmental fates. Nat Commun 2015; 6:6546. [PMID: 25775035 DOI: 10.1038/ncomms7546] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Accepted: 02/05/2015] [Indexed: 11/09/2022] Open
Abstract
In embryonic stem cells, extracellular signals are required to derepress developmental promoters to drive lineage specification, but the proteins involved in connecting extrinsic cues to relaxation of chromatin remain unknown. We demonstrate that the helix-loop-helix (HLH) protein, HEB, directly associates with the Polycomb repressive complex 2 (PRC2) at a subset of developmental promoters, including at genes involved in mesoderm and endoderm specification and at the Hox and Fox gene families. While we show that depletion of HEB does not affect mouse ESCs, it does cause premature differentiation after exposure to Activin. Further, we find that HEB deposition at developmental promoters is dependent upon PRC2 and independent of Nodal, whereas HEB association with SMAD2/3 elements is dependent of Nodal, but independent of PRC2. We suggest that HEB is a fundamental link between Nodal signalling, the derepression of a specific class of poised promoters during differentiation, and lineage specification in mouse ESCs.
Collapse
|
81
|
di Masi A, Leboffe L, De Marinis E, Pagano F, Cicconi L, Rochette-Egly C, Lo-Coco F, Ascenzi P, Nervi C. Retinoic acid receptors: from molecular mechanisms to cancer therapy. Mol Aspects Med 2015; 41:1-115. [PMID: 25543955 DOI: 10.1016/j.mam.2014.12.003] [Citation(s) in RCA: 243] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Accepted: 12/15/2014] [Indexed: 02/07/2023]
Abstract
Retinoic acid (RA), the major bioactive metabolite of retinol or vitamin A, induces a spectrum of pleiotropic effects in cell growth and differentiation that are relevant for embryonic development and adult physiology. The RA activity is mediated primarily by members of the retinoic acid receptor (RAR) subfamily, namely RARα, RARβ and RARγ, which belong to the nuclear receptor (NR) superfamily of transcription factors. RARs form heterodimers with members of the retinoid X receptor (RXR) subfamily and act as ligand-regulated transcription factors through binding specific RA response elements (RAREs) located in target genes promoters. RARs also have non-genomic effects and activate kinase signaling pathways, which fine-tune the transcription of the RA target genes. The disruption of RA signaling pathways is thought to underlie the etiology of a number of hematological and non-hematological malignancies, including leukemias, skin cancer, head/neck cancer, lung cancer, breast cancer, ovarian cancer, prostate cancer, renal cell carcinoma, pancreatic cancer, liver cancer, glioblastoma and neuroblastoma. Of note, RA and its derivatives (retinoids) are employed as potential chemotherapeutic or chemopreventive agents because of their differentiation, anti-proliferative, pro-apoptotic, and anti-oxidant effects. In humans, retinoids reverse premalignant epithelial lesions, induce the differentiation of myeloid normal and leukemic cells, and prevent lung, liver, and breast cancer. Here, we provide an overview of the biochemical and molecular mechanisms that regulate the RA and retinoid signaling pathways. Moreover, mechanisms through which deregulation of RA signaling pathways ultimately impact on cancer are examined. Finally, the therapeutic effects of retinoids are reported.
Collapse
Affiliation(s)
- Alessandra di Masi
- Department of Science, Roma Tre University, Viale Guglielmo Marconi 446, Roma I-00146, Italy
| | - Loris Leboffe
- Department of Science, Roma Tre University, Viale Guglielmo Marconi 446, Roma I-00146, Italy
| | - Elisabetta De Marinis
- Department of Medical and Surgical Sciences and Biotechnologies, University of Roma "La Sapienza", Corso della Repubblica 79, Latina I-04100
| | - Francesca Pagano
- Department of Medical and Surgical Sciences and Biotechnologies, University of Roma "La Sapienza", Corso della Repubblica 79, Latina I-04100
| | - Laura Cicconi
- Department of Biomedicine and Prevention, University of Roma "Tor Vergata", Via Montpellier 1, Roma I-00133, Italy; Laboratory of Neuro-Oncohematology, Santa Lucia Foundation, Via Ardeatina, 306, Roma I-00142, Italy
| | - Cécile Rochette-Egly
- Department of Functional Genomics and Cancer, IGBMC, CNRS UMR 7104 - Inserm U 964, University of Strasbourg, 1 rue Laurent Fries, BP10142, Illkirch Cedex F-67404, France.
| | - Francesco Lo-Coco
- Department of Biomedicine and Prevention, University of Roma "Tor Vergata", Via Montpellier 1, Roma I-00133, Italy; Laboratory of Neuro-Oncohematology, Santa Lucia Foundation, Via Ardeatina, 306, Roma I-00142, Italy.
| | - Paolo Ascenzi
- Interdepartmental Laboratory for Electron Microscopy, Roma Tre University, Via della Vasca Navale 79, Roma I-00146, Italy.
| | - Clara Nervi
- Department of Medical and Surgical Sciences and Biotechnologies, University of Roma "La Sapienza", Corso della Repubblica 79, Latina I-04100.
| |
Collapse
|
82
|
Infante T, Mancini FP, Lanza A, Soricelli A, de Nigris F, Napoli C. Polycomb YY1 is a critical interface between epigenetic code and miRNA machinery after exposure to hypoxia in malignancy. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2015; 1853:975-86. [PMID: 25644713 DOI: 10.1016/j.bbamcr.2015.01.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Revised: 12/19/2014] [Accepted: 01/16/2015] [Indexed: 02/09/2023]
Abstract
Yin Yang 1 (YY1) is a member of polycomb protein family involved in epigenetic modifications and transcriptional controls. We have shown that YY1 acts as positive regulator of tumor growth and angiogenesis by interfering with the VEGFA network. Yet, the link between polycomb chromatin complex and hypoxia regulation of VEGFA is still poorly understood. Here, we establish that hypoxia impairs YY1 binding to VEGFA mRNA 3'UTR (p<0.001) in bone malignancy. Moreover, RNA immunoprecipitation reveals the formation of triplex nuclear complexes among YY1, VEGFA DNA, mRNA, and unreached about 200 fold primiRNA 200b and 200c via Dicer protein. In this complex, YY1 is necessary to maintain the steady-state level of VEGFA expression while its silencing increases VEGFA mRNA half-life at 4 h and impairs the maturation of miRNA 200b/c. Hypoxia promotes histone modification through ubiquitination both of YY1 and Dicer proteins. Hypoxia-mediated down-regulation of YY1 and Dicer changes post-transcriptional VEGFA regulation by resulting in the accumulation of primiRNA200b/c in comparison to mature miRNAs (p<0.001). Given the regulatory functions of VEGFA on cellular activities to promote neoangiogenesis, we conclude that YY1 acts as novel critical interface between epigenetic code and miRNAs machinery under chronic hypoxia in malignancy.
Collapse
Affiliation(s)
| | - Francesco P Mancini
- Department of Sciences and Technologies, University of Sannio, Benevento, Italy
| | - Alessandro Lanza
- Department Multidisciplinary of Specialistic Medical Surgery and Odontostomatologic of Second University of Naples, Naples Italy
| | | | - Filomena de Nigris
- Department of Biochemistry Biophysics and General Pathology, Second University of Naples, Naples Italy.
| | - Claudio Napoli
- IRCCS, SDN, Via E. Gianturco 113, 80143 Naples, Italy; Department of Biochemistry Biophysics and General Pathology, Second University of Naples, Naples Italy
| |
Collapse
|
83
|
Huang G, Ye S, Zhou X, Liu D, Ying QL. Molecular basis of embryonic stem cell self-renewal: from signaling pathways to pluripotency network. Cell Mol Life Sci 2015; 72:1741-57. [PMID: 25595304 DOI: 10.1007/s00018-015-1833-2] [Citation(s) in RCA: 109] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Revised: 12/17/2014] [Accepted: 01/08/2015] [Indexed: 12/18/2022]
Abstract
Embryonic stem cells (ESCs) can be maintained in culture indefinitely while retaining the capacity to generate any type of cell in the body, and therefore not only hold great promise for tissue repair and regeneration, but also provide a powerful tool for modeling human disease and understanding biological development. In order to fulfill the full potential of ESCs, it is critical to understand how ESC fate, whether to self-renew or to differentiate into specialized cells, is regulated. On the molecular level, ESC fate is controlled by the intracellular transcriptional regulatory networks that respond to various extrinsic signaling stimuli. In this review, we discuss and compare important signaling pathways in the self-renewal and differentiation of mouse, rat, and human ESCs with an emphasis on how these pathways integrate into ESC-specific transcription circuitries. This will be beneficial for understanding the common and conserved mechanisms that govern self-renewal, and for developing novel culture conditions that support ESC derivation and maintenance.
Collapse
Affiliation(s)
- Guanyi Huang
- Center for Stem Cell and Translational Medicine, School of Life Sciences, Anhui University, Hefei, 230601, PR China
| | | | | | | | | |
Collapse
|
84
|
Bianchi A, Lanzuolo C. Into the chromatin world: Role of nuclear architecture in epigenome regulation. AIMS BIOPHYSICS 2015. [DOI: 10.3934/biophy.2015.4.585] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
|
85
|
Epigenetic regulation of open chromatin in pluripotent stem cells. Transl Res 2015; 165:18-27. [PMID: 24695097 PMCID: PMC4163141 DOI: 10.1016/j.trsl.2014.03.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Revised: 03/03/2014] [Accepted: 03/06/2014] [Indexed: 01/10/2023]
Abstract
The recent progress in pluripotent stem cell research has opened new avenues of disease modeling, drug screening, and transplantation of patient-specific tissues unimaginable until a decade ago. The central mechanism underlying pluripotency is epigenetic gene regulation; the majority of cell signaling pathways, both extracellular and cytoplasmic, alter, eventually, the epigenetic status of their target genes during the process of activating or suppressing the genes to acquire or maintain pluripotency. It has long been thought that the chromatin of pluripotent stem cells is open globally to enable the timely activation of essentially all genes in the genome during differentiation into multiple lineages. The current article reviews descriptive observations and the epigenetic machinery relevant to what is supposed to be globally open chromatin in pluripotent stem cells, including microscopic appearance, permissive gene transcription, chromatin remodeling complexes, histone modifications, DNA methylation, noncoding RNAs, dynamic movement of chromatin proteins, nucleosome accessibility and positioning, and long-range chromosomal interactions. Detailed analyses of each element, however, have revealed that the globally open chromatin hypothesis is not necessarily supported by some of the critical experimental evidence, such as genomewide nucleosome accessibility and nucleosome positioning. Greater understanding of epigenetic gene regulation is expected to determine the true nature of the so-called globally open chromatin in pluripotent stem cells.
Collapse
|
86
|
Thornton SR, Butty VL, Levine SS, Boyer LA. Polycomb Repressive Complex 2 regulates lineage fidelity during embryonic stem cell differentiation. PLoS One 2014; 9:e110498. [PMID: 25333635 PMCID: PMC4204901 DOI: 10.1371/journal.pone.0110498] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2014] [Accepted: 09/20/2014] [Indexed: 11/18/2022] Open
Abstract
Polycomb Repressive Complex 2 (PRC2) catalyzes histone H3 lysine 27 tri-methylation (H3K27me3), an epigenetic modification associated with gene repression. H3K27me3 is enriched at the promoters of a large cohort of developmental genes in embryonic stem cells (ESCs). Loss of H3K27me3 leads to a failure of ESCs to properly differentiate, making it difficult to determine the precise roles of PRC2 during lineage commitment. Moreover, while studies suggest that PRC2 prevents DNA methylation, how these two epigenetic regulators coordinate to regulate lineage programs is poorly understood. Using several PRC2 mutant ESC lines that maintain varying levels of H3K27me3, we found that partial maintenance of H3K27me3 allowed for proper temporal activation of lineage genes during directed differentiation of ESCs to spinal motor neurons (SMNs). In contrast, genes that function to specify other lineages failed to be repressed in these cells, suggesting that PRC2 is also necessary for lineage fidelity. We also found that loss of H3K27me3 leads to a modest gain in DNA methylation at PRC2 target regions in both ESCs and in SMNs. Our study demonstrates a critical role for PRC2 in safeguarding lineage decisions and in protecting genes against inappropriate DNA methylation.
Collapse
Affiliation(s)
- Seraphim R. Thornton
- Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
| | - Vincent L. Butty
- BioMicro Center, Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
| | - Stuart S. Levine
- BioMicro Center, Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
| | - Laurie A. Boyer
- Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
- * E-mail:
| |
Collapse
|
87
|
Abstract
Over the last three decades, studies of the α- and β-globin genes clusters have led to elucidation of the general principles of mammalian gene regulation, such as RNA stability, termination of transcription, and, more importantly, the identification of remote regulatory elements. More recently, detailed studies of α-globin regulation, using both mouse and human loci, allowed the dissection of the sequential order in which transcription factors are recruited to the locus during lineage specification. These studies demonstrated the importance of the remote regulatory elements in the recruitment of RNA polymerase II (PolII) together with their role in the generation of intrachromosomal loops within the locus and the removal of polycomb complexes during differentiation. The multiple roles attributed to remote regulatory elements that have emerged from these studies will be discussed.
Collapse
Affiliation(s)
- Douglas Vernimmen
- The Roslin Institute, Developmental Biology Division, University of Edinburgh, Easter Bush, Midlothian, United Kingdom
- * E-mail:
| |
Collapse
|
88
|
Koike H, Ouchi R, Ueno Y, Nakata S, Obana Y, Sekine K, Zheng YW, Takebe T, Isono K, Koseki H, Taniguchi H. Polycomb group protein Ezh2 regulates hepatic progenitor cell proliferation and differentiation in murine embryonic liver. PLoS One 2014; 9:e104776. [PMID: 25153170 PMCID: PMC4143191 DOI: 10.1371/journal.pone.0104776] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Accepted: 07/14/2014] [Indexed: 01/03/2023] Open
Abstract
In embryonic liver, hepatic progenitor cells are actively proliferating and generate a fundamental cellular pool for establishing parenchymal components. However, the molecular basis for the expansion of the progenitors maintaining their immature state remains elusive. Polycomb group proteins regulate gene expression throughout the genome by modulating of chromatin structure and play crucial roles in development. Enhancer of zeste homolog 2 (Ezh2), a key component of polycomb group proteins, catalyzes tri-methylation of lysine 27 of histone H3 (H3K27me3), which trigger the gene suppression. In the present study, we investigated a role of Ezh2 in the regulation of the expanding hepatic progenitor population in vivo. We found that Ezh2 is highly expressed in the actively proliferating cells at the early developmental stage. Using a conditional knockout mouse model, we show that the deletion of the SET domain of Ezh2, which is responsible for catalytic induction of H3K27me3, results in significant reduction of the total liver size, absolute number of liver parenchymal cells, and hepatic progenitor cell population in size. A clonal colony assay in the hepatic progenitor cells directly isolated from in vivo fetal livers revealed that the bi-potent clonogenicity was significantly attenuated by the Ezh2 loss of function. Moreover, a marker expression based analysis and a global gene expression analysis showed that the knockout of Ezh2 inhibited differentiation to hepatocyte with reduced expression of a number of liver-function related genes. Taken together, our results indicate that Ezh2 is required for the hepatic progenitor expansion in vivo, which is essential for the functional maturation of embryonic liver, through its activity for catalyzing H3K27me3.
Collapse
Affiliation(s)
- Hiroyuki Koike
- Department of Regenerative Medicine, Yokohama City University Graduate School of Medicine, Kanazawa-ku, Yokohama, Kanagawa, Japan
| | - Rie Ouchi
- Department of Regenerative Medicine, Yokohama City University Graduate School of Medicine, Kanazawa-ku, Yokohama, Kanagawa, Japan
| | - Yasuharu Ueno
- Department of Regenerative Medicine, Yokohama City University Graduate School of Medicine, Kanazawa-ku, Yokohama, Kanagawa, Japan
| | - Susumu Nakata
- Division of Oncological Pathology, Aichi Cancer Center Research Institute, Chikusa-ku, Nagoya, Japan
| | - Yuta Obana
- Department of Regenerative Medicine, Yokohama City University Graduate School of Medicine, Kanazawa-ku, Yokohama, Kanagawa, Japan
| | - Keisuke Sekine
- Department of Regenerative Medicine, Yokohama City University Graduate School of Medicine, Kanazawa-ku, Yokohama, Kanagawa, Japan
| | - Yun-Wen Zheng
- Department of Regenerative Medicine, Yokohama City University Graduate School of Medicine, Kanazawa-ku, Yokohama, Kanagawa, Japan
| | - Takanori Takebe
- Department of Regenerative Medicine, Yokohama City University Graduate School of Medicine, Kanazawa-ku, Yokohama, Kanagawa, Japan
- Project Leader of Advanced Medical Research Center, Yokohama City University, Kanazawa-ku, Yokohama, Kanagawa, Japan
- PRESTO, Japan Science and Technology Agency, Saitama, Japan
| | - Kyoichi Isono
- Laboratory for Developmental Genetics, RIKEN Research Center for Allergy and Immunology, Tsurumi-ku, Yokohama, Kanagawa, Japan
| | - Haruhiko Koseki
- Laboratory for Developmental Genetics, RIKEN Research Center for Allergy and Immunology, Tsurumi-ku, Yokohama, Kanagawa, Japan
| | - Hideki Taniguchi
- Department of Regenerative Medicine, Yokohama City University Graduate School of Medicine, Kanazawa-ku, Yokohama, Kanagawa, Japan
- Project Leader of Advanced Medical Research Center, Yokohama City University, Kanazawa-ku, Yokohama, Kanagawa, Japan
- * E-mail:
| |
Collapse
|
89
|
Rinaldi L, Benitah SA. Epigenetic regulation of adult stem cell function. FEBS J 2014; 282:1589-604. [PMID: 25060320 DOI: 10.1111/febs.12946] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Revised: 07/17/2014] [Accepted: 07/22/2014] [Indexed: 01/09/2023]
Abstract
Understanding the cellular and molecular mechanisms that specify cell lineages throughout development, and that maintain tissue homeostasis during adulthood, is paramount towards our understanding of why we age or develop pathologies such as cancer. Epigenetic mechanisms ensure that genetically identical cells acquire different fates during embryonic development and are therefore essential for the proper progression of development. How they do so is still a matter of intense investigation, but there is sufficient evidence indicating that they act in a concerted manner with inductive signals and tissue-specific transcription factors to promote and stabilize fate changes along the three germ layers during development. In consequence, it is generally hypothesized that epigenetic mechanisms are also required for the continuous maintenance of cell fate during adulthood. However, in vivo models in which different epigenetic factors have been depleted in different tissues do not show overt changes in cell lineage, thus not strongly supporting this view. Instead, the function of some of these factors appears to be primarily associated with tissue functionality, and a strong causal relationship has been established between their misregulation and a diseased state. In this review, we summarize our current knowledge of the role of epigenetic factors in adult stem cell function and tissue homeostasis.
Collapse
Affiliation(s)
- Lorenzo Rinaldi
- Centre for Genomic Regulation, Barcelona, Spain; Universitat Pompeu Fabra, Barcelona, Spain; Institute for Research in Biomedicine, Barcelona, Spain
| | | |
Collapse
|
90
|
Xu CR, Li LC, Donahue G, Ying L, Zhang YW, Gadue P, Zaret KS. Dynamics of genomic H3K27me3 domains and role of EZH2 during pancreatic endocrine specification. EMBO J 2014; 33:2157-70. [PMID: 25107471 DOI: 10.15252/embj.201488671] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Endoderm cells undergo sequential fate choices to generate insulin-secreting beta cells. Ezh2 of the PRC2 complex, which generates H3K27me3, modulates the transition from endoderm to pancreas progenitors, but the role of Ezh2 and H3K27me3 in the next transition to endocrine progenitors is unknown. We isolated endoderm cells, pancreas progenitors, and endocrine progenitors from different staged mouse embryos and analyzed H3K27me3 genome-wide. Unlike the decline in H3K27me3 domains reported during embryonic stem cell differentiation in vitro, we find that H3K27me3 domains increase in number during endocrine progenitor development in vivo. Genes that lose the H3K27me3 mark typically encode transcriptional regulators, including those for pro-endocrine fates, whereas genes that acquire the mark typically are involved in cell biology and morphogenesis. Deletion of Ezh2 at the pancreas progenitor stage enhanced the production of endocrine progenitors and beta cells. Inhibition of EZH2 in embryonic pancreas explants and in human embryonic stem cell cultures increased endocrine progenitors in vitro. Our studies reveal distinct dynamics in H3K27me3 targets in vivo and a means to modulate beta cell development from stem cells.
Collapse
Affiliation(s)
- Cheng-Ran Xu
- Institute for Regenerative Medicine, Epigenetics Program, Department of Cell and Developmental Biology, Perelman School of Medicine University of Pennsylvania, Philadelphia, PA, USA Ministry of Education Key Laboratory of Cell Proliferation, College of Life Sciences Peking-Tsinghua Center for Life Sciences Peking University, Beijing, China
| | - Lin-Chen Li
- Ministry of Education Key Laboratory of Cell Proliferation, College of Life Sciences Peking-Tsinghua Center for Life Sciences Peking University, Beijing, China
| | - Greg Donahue
- Institute for Regenerative Medicine, Epigenetics Program, Department of Cell and Developmental Biology, Perelman School of Medicine University of Pennsylvania, Philadelphia, PA, USA
| | - Lei Ying
- Department of Pathology and Laboratory Medicine, Center for Cellular and Molecular Therapeutics, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Yu-Wei Zhang
- Ministry of Education Key Laboratory of Cell Proliferation, College of Life Sciences Peking-Tsinghua Center for Life Sciences Peking University, Beijing, China
| | - Paul Gadue
- Department of Pathology and Laboratory Medicine, Center for Cellular and Molecular Therapeutics, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Kenneth S Zaret
- Institute for Regenerative Medicine, Epigenetics Program, Department of Cell and Developmental Biology, Perelman School of Medicine University of Pennsylvania, Philadelphia, PA, USA
| |
Collapse
|
91
|
Krapivinsky G, Krapivinsky L, Manasian Y, Clapham DE. The TRPM7 chanzyme is cleaved to release a chromatin-modifying kinase. Cell 2014; 157:1061-72. [PMID: 24855944 DOI: 10.1016/j.cell.2014.03.046] [Citation(s) in RCA: 127] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2013] [Revised: 01/13/2014] [Accepted: 03/12/2014] [Indexed: 02/05/2023]
Abstract
TRPM7 is a ubiquitous ion channel and kinase, a unique "chanzyme," required for proper early embryonic development. It conducts Zn(2+), Mg(2+), and Ca(2+) as well as monovalent cations and contains a functional serine/threonine kinase at its carboxyl terminus. Here, we show that in normal tissues and cell lines, the kinase is proteolytically cleaved from the channel domain in a cell-type-specific manner. These TRPM7 cleaved kinase fragments (M7CKs) translocate to the nucleus and bind multiple components of chromatin-remodeling complexes, including Polycomb group proteins. In the nucleus, the kinase phosphorylates specific serines/threonines of histones. M7CK-dependent phosphorylation of H3Ser10 at promoters of TRPM7-dependent genes correlates with their activity. We also demonstrate that cytosolic free [Zn(2+)] is TRPM7 dependent and regulates M7CK binding to transcription factors containing zinc-finger domains. These findings suggest that TRPM7-mediated modulation of intracellular Zn(2+) concentration couples ion-channel signaling to epigenetic chromatin covalent modifications that affect gene expression patterns. PAPERCLIP:
Collapse
Affiliation(s)
- Grigory Krapivinsky
- Howard Hughes Medical Institute, Department of Cardiology, Boston Children's Hospital, Enders Building 1309, 320 Longwood Avenue, Boston, MA 02115, USA
| | - Luba Krapivinsky
- Howard Hughes Medical Institute, Department of Cardiology, Boston Children's Hospital, Enders Building 1309, 320 Longwood Avenue, Boston, MA 02115, USA
| | - Yunona Manasian
- Howard Hughes Medical Institute, Department of Cardiology, Boston Children's Hospital, Enders Building 1309, 320 Longwood Avenue, Boston, MA 02115, USA
| | - David E Clapham
- Howard Hughes Medical Institute, Department of Cardiology, Boston Children's Hospital, Enders Building 1309, 320 Longwood Avenue, Boston, MA 02115, USA; Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA.
| |
Collapse
|
92
|
Maclary E, Hinten M, Harris C, Kalantry S. Long nonoding RNAs in the X-inactivation center. Chromosome Res 2014; 21:601-614. [PMID: 24297756 DOI: 10.1007/s10577-013-9396-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The X-inactivation center is a hotbed of functional long noncoding RNAs in eutherian mammals. These RNAs are thought to help orchestrate the epigenetic transcriptional states of the two X-chromosomes in females as well as of the single X-chromosome in males. To balance X-linked gene expression between the sexes, females undergo transcriptional silencing of most genes on one of the two X-chromosomes in a process termed X-chromosome inactivation. While one X-chromosome is inactivated, the other X-chromosome remains active. Moreover, with a few notable exceptions, the originally established epigenetic transcriptional profiles of the two X-chromosomes is maintained as such through many rounds of cell division, essentially for the life of the organism. The stable and divergent transcriptional fates of the two X-chromosomes, despite residing in a shared nucleoplasm, make X-inactivation a paradigm of epigenetic transcriptional regulation. Originally proposed in 1961 by Mary Lyon, the X-inactivation hypothesis has been validated through much experimentation. In the last 25 years, the discovery and functional characterization has firmly established X-linked long noncoding RNAs as key players in choreographing X-chromosome inactivation.
Collapse
Affiliation(s)
- Emily Maclary
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor, MI 48105
| | - Michael Hinten
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor, MI 48105
| | - Clair Harris
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor, MI 48105
| | - Sundeep Kalantry
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor, MI 48105
| |
Collapse
|
93
|
Darr OA, Colacino JA, Tang AL, McHugh JB, Bellile EL, Bradford CR, Prince MP, Chepeha DB, Rozek LS, Moyer JS. Epigenetic alterations in metastatic cutaneous carcinoma. Head Neck 2014; 37:994-1001. [PMID: 24700717 DOI: 10.1002/hed.23701] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2013] [Revised: 03/11/2014] [Accepted: 03/28/2014] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Squamous cell carcinoma (SCC) and basal cell carcinoma (BCC) are the 2 most common cutaneous carcinomas. Molecular profiles predicting metastasis of these cancers have not been identified. METHODS Epigenetic profiles of 37 primary cases of cutaneous SCC and BCC were quantified via the Illumina Goldengate Cancer Panel. Differential protein expression by metastatic potential was analyzed in 110 total cases by immunohistochemical (IHC) staining. RESULTS Unsupervised hierarchical clustering analysis revealed that metastatic BCCs had a methylation profile resembling cutaneous SCCs. Metastatic cutaneous SCCs were found to be hypermethylated at FRZB (median methylation: 46.7% vs 4.7%; p = 4 × 10(-5) ). Metastatic BCCs were found to be hypomethylated at MYCL2 (median methylation: 3.8% vs 83.4%; p = 1.9 × 10(-6) ). Immunohistochemical staining revealed few differences between metastatic and nonmetastatic cancers. CONCLUSION Metastatic primary BCCs and cutaneous SCCs had distinct epigenetic profiles when compared to their nonmetastatic counterparts. Epigenetic profiling may prove useful in future diagnosis and prevention of advanced nonmelanoma skin cancers.
Collapse
Affiliation(s)
- Owen A Darr
- Department of Otolaryngology, University of Michigan Medical School, Ann Arbor, Michigan
| | - Justin A Colacino
- Department of Environmental Health Sciences, University of Michigan School of Public Health, Ann Arbor, Michigan
| | - Alice L Tang
- Department of Otolaryngology, University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Jonathan B McHugh
- Department of Pathology, University of Michigan Medical School, Ann Arbor, Michigan
| | - Emily L Bellile
- Comprehensive Cancer Center, University of Michigan, Ann Arbor, Michigan
| | - Carol R Bradford
- Department of Otolaryngology, University of Michigan Medical School, Ann Arbor, Michigan
| | - Mark P Prince
- Department of Otolaryngology, University of Michigan Medical School, Ann Arbor, Michigan
| | - Douglas B Chepeha
- Department of Otolaryngology, University of Michigan Medical School, Ann Arbor, Michigan
| | - Laura S Rozek
- Department of Otolaryngology, University of Michigan Medical School, Ann Arbor, Michigan.,Department of Environmental Health Sciences, University of Michigan School of Public Health, Ann Arbor, Michigan
| | - Jeffrey S Moyer
- Department of Otolaryngology, University of Michigan Medical School, Ann Arbor, Michigan
| |
Collapse
|
94
|
Pethe P, Nagvenkar P, Bhartiya D. Polycomb group protein expression during differentiation of human embryonic stem cells into pancreatic lineage in vitro. BMC Cell Biol 2014; 15:18. [PMID: 24885493 PMCID: PMC4038052 DOI: 10.1186/1471-2121-15-18] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2013] [Accepted: 05/20/2014] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Polycomb Group (PcG) proteins are chromatin modifiers involved in early embryonic development as well as in proliferation of adult stem cells and cancer cells. PcG proteins form large repressive complexes termed Polycomb Repressive Complexes (PRCs) of which PRC1 and PRC2 are well studied. Differentiation of human Embryonic Stem (hES) cells into insulin producing cells has been achieved to limited extent, but several aspects of differentiation remain unexplored. The PcG protein dynamics in human embryonic stem (hES) cells during differentiation into pancreatic lineage has not yet been reported. In the present study, the expression of RING1A, RING1B, BMI1, CBX2, SUZ12, EZH2, EED and JARID2 during differentiation of hES cells towards pancreatic lineage was examined. RESULTS In-house derived hES cell line KIND1 was used to study expression of PcG protein upon spontaneous and directed differentiation towards pancreatic lineage. qRT-PCR analysis showed expression of gene transcripts for various lineages in spontaneously differentiated KIND1 cells, but no differentiation into pancreatic lineage was observed. Directed differentiation induced KIND1 cells grown under feeder-free conditions to transition from definitive endoderm (Day 4), primitive gut tube stage (Day 8) and pancreatic progenitors (Day 12-Day 16) as evident from expression of SOX17, PDX1 and SOX9 by qRT-PCR and Western blotting. In spontaneously differentiating KIND1 cells, RING1A and SUZ12 were upregulated at day 15, while other PcG transcripts were downregulated. qRT-PCR analysis showed transcripts of RING1B, BMI1, SUZ12, EZH2 and EED were upregulated, while RING1A and CBX2 expression remained low and JARID2 was downregulated during directed differentiation of KIND1 cells. Upregulation of BMI1, EZH2 and SUZ12 during differentiation into pancreatic lineage was also confirmed by Western blotting. Histone modifications such as H3K27 trimethylation and monoubiquitinylation of H2AK119 increased during differentiation into pancreatic lineage as seen by Western blotting. CONCLUSION Our study shows expression of PcG proteins was distinct during spontaneous and directed differentiation. Differentiation into pancreatic lineage was achieved by directed differentiation approach and was associated with increased expression of PcG proteins RING1B, BMI1, EZH2 and SUZ12 accompanied by increase in monoubiquitinylation of H2AK119 and trimethylation of H3K27.
Collapse
Affiliation(s)
- Prasad Pethe
- Stem Cell Biology Department, National Institute for Research in Reproductive Health, J.M. Street, Parel-12, Mumbai, India
| | - Punam Nagvenkar
- Stem Cell Biology Department, National Institute for Research in Reproductive Health, J.M. Street, Parel-12, Mumbai, India
| | - Deepa Bhartiya
- Stem Cell Biology Department, National Institute for Research in Reproductive Health, J.M. Street, Parel-12, Mumbai, India
| |
Collapse
|
95
|
The histone H2A deubiquitinase Usp16 regulates embryonic stem cell gene expression and lineage commitment. Nat Commun 2014; 5:3818. [PMID: 24784029 PMCID: PMC4060806 DOI: 10.1038/ncomms4818] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2014] [Accepted: 04/07/2014] [Indexed: 11/09/2022] Open
Abstract
Polycomb Repressive Complex 1 and histone H2A ubiquitination (ubH2A) contribute to embryonic stem cell (ESC) pluripotency by repressing lineage-specific gene expression. However, whether active deubiquitination co-regulates ubH2A levels in ESCs and during differentiation is not known. Here we report that Usp16, a histone H2A deubiquitinase, regulates H2A deubiquitination and gene expression in ESCs, and importantly, is required for ESC differentiation. Usp16 knockout is embryonic lethal in mice, but does not affect ESC viability or identity. Usp16 binds to the promoter regions of a large number of genes in ESCs, and Usp16 binding is inversely correlated with ubH2A levels, and positively correlates with gene expression levels. Intriguingly, Usp16−/− ESCs fail to differentiate due to ubH2A-mediated repression of lineage-specific genes. Finally, Usp16, but not a catalytically inactive mutant, rescues the differentiation defects of Usp16−/− ESCs. Therefore, this study identifies Usp16 and H2A deubiquitination as critical regulators of ESC gene expression and differentiation.
Collapse
|
96
|
Basu A, Dasari V, Mishra RK, Khosla S. The CpG island encompassing the promoter and first exon of human DNMT3L gene is a PcG/TrX response element (PRE). PLoS One 2014; 9:e93561. [PMID: 24743422 PMCID: PMC3990577 DOI: 10.1371/journal.pone.0093561] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2013] [Accepted: 03/07/2014] [Indexed: 01/27/2023] Open
Abstract
DNMT3L, a member of DNA methyltransferases family, is present only in mammals. As it provides specificity to the action of de novo methyltransferases, DNMT3A and DNMT3B and interacts with histone H3, DNMT3L has been invoked as the molecule that can read the histone code and translate it into DNA methylation. It plays an important role in the initiation of genomic imprints during gametogenesis and in nuclear reprogramming. With important functions attributed to it, it is imperative that the DNMT3L expression is tightly controlled. Previously, we had identified a CpG island within the human DNMT3L promoter and first exon that showed loss of DNA methylation in cancer samples. Here we show that this Differentially Methylated CpG island within DNMT3L (DNMT3L DMC) acts to repress transcription, is a Polycomb/Trithorax Response Element (PRE) and interacts with both PRC1 and PRC2 Polycomb repressive complexes. In addition, it adopts inactive chromatin conformation and is associated with other inactive chromatin-specific proteins like SUV39H1 and HP1. The presence of DNMT3L DMC also influences the adjacent promoter to adopt repressive histone post-translational modifications. Due to its association with multiple layers of repressive epigenetic modifications, we believe that PRE within the DNMT3L DMC is responsible for the tight regulation of DNMT3L expression and the aberrant epigenetic modifications of this region leading to DNMT3L overexpression could be the reason of nuclear programming during carcinogenesis.
Collapse
Affiliation(s)
- Amitava Basu
- Centre for DNA Fingerprinting and Diagnostics (CDFD), Nampally, Hyderabad, India
| | - Vasanthi Dasari
- Centre for Cellular and Molecular Biology (CCMB), Council of Scientific and Industrial Research (CSIR), Hyderabad, India
| | - Rakesh K. Mishra
- Centre for Cellular and Molecular Biology (CCMB), Council of Scientific and Industrial Research (CSIR), Hyderabad, India
| | - Sanjeev Khosla
- Centre for DNA Fingerprinting and Diagnostics (CDFD), Nampally, Hyderabad, India
| |
Collapse
|
97
|
Belle JI, Nijnik A. H2A-DUBbing the mammalian epigenome: expanding frontiers for histone H2A deubiquitinating enzymes in cell biology and physiology. Int J Biochem Cell Biol 2014; 50:161-74. [PMID: 24647359 DOI: 10.1016/j.biocel.2014.03.004] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Revised: 03/05/2014] [Accepted: 03/07/2014] [Indexed: 12/16/2022]
Abstract
Posttranslational modifications of histone H2A through the attachment of ubiquitin or poly-ubiquitin conjugates are common in mammalian genomes and play an important role in the regulation of chromatin structure, gene expression, and DNA repair. Histone H2A deubiquitinases (H2A-DUBs) are a group of structurally diverse enzymes that catalyze the removal ubiquitin from histone H2A. In this review we provide a concise summary of the mechanisms that mediate histone H2A ubiquitination in mammalian cells, and review our current knowledge of mammalian H2A-DUBs, their biochemical activities, and recent developments in our understanding of their functions in mammalian physiology.
Collapse
Affiliation(s)
- Jad I Belle
- Department of Physiology, McGill University, Canada; Complex Traits Group, McGill University, Canada
| | - Anastasia Nijnik
- Department of Physiology, McGill University, Canada; Complex Traits Group, McGill University, Canada.
| |
Collapse
|
98
|
Schoorlemmer J, Pérez-Palacios R, Climent M, Guallar D, Muniesa P. Regulation of Mouse Retroelement MuERV-L/MERVL Expression by REX1 and Epigenetic Control of Stem Cell Potency. Front Oncol 2014; 4:14. [PMID: 24567914 PMCID: PMC3915180 DOI: 10.3389/fonc.2014.00014] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Accepted: 01/21/2014] [Indexed: 11/17/2022] Open
Abstract
About half of the mammalian genome is occupied by DNA sequences that originate from transposable elements. Retrotransposons can modulate gene expression in different ways and, particularly retrotransposon-derived long terminal repeats, profoundly shape expression of both surrounding and distant genomic loci. This is especially important in pre-implantation development, during which extensive reprograming of the genome takes place and cells pass through totipotent and pluripotent states. At this stage, the main mechanism responsible for retrotransposon silencing, i.e., DNA methylation, is inoperative. A particular retrotransposon called muERV-L/MERVL is expressed during pre-implantation stages and contributes to the plasticity of mouse embryonic stem cells. This review will focus on the role of MERVL-derived sequences as controlling elements of gene expression specific for pre-implantation development, two-cell stage-specific gene expression, and stem cell pluripotency, the epigenetic mechanisms that control their expression, and the contributions of the pluripotency marker REX1 and the related Yin Yang 1 family of transcription factors to this regulation process.
Collapse
Affiliation(s)
- Jon Schoorlemmer
- Regenerative Medicine Program, Instituto Aragonés de Ciencias de la Salud , Zaragoza , Spain ; ARAID Foundation , Zaragoza , Spain
| | - Raquel Pérez-Palacios
- Regenerative Medicine Program, Instituto Aragonés de Ciencias de la Salud , Zaragoza , Spain
| | - María Climent
- Departamento de Anatomía, Embriología y Genética Animal, Facultad de Veterinaria, Universidad de Zaragoza , Zaragoza , Spain
| | - Diana Guallar
- Regenerative Medicine Program, Instituto Aragonés de Ciencias de la Salud , Zaragoza , Spain
| | - Pedro Muniesa
- Departamento de Anatomía, Embriología y Genética Animal, Facultad de Veterinaria, Universidad de Zaragoza , Zaragoza , Spain
| |
Collapse
|
99
|
Oncogenic Y641 mutations in EZH2 prevent Jak2/β-TrCP-mediated degradation. Oncogene 2014; 34:445-54. [PMID: 24469040 DOI: 10.1038/onc.2013.571] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2013] [Revised: 11/14/2013] [Accepted: 12/03/2013] [Indexed: 12/16/2022]
Abstract
EZH2 (enhancer of zeste homolog 2) is a critical enzymatic subunit of the polycomb repressive complex 2 (PRC2), which trimethylates histone H3 (H3K27) to mediate gene repression. Somatic mutations, overexpression and hyperactivation of EZH2 have been implicated in the pathogenesis of several forms of cancer. In particular, recurrent gain-of-function mutations targeting EZH2 Y641 occur most frequently in follicular lymphoma and aggressive diffuse large B-cell lymphoma and are associated with H3K27me3 hyperactivation, which contributes to lymphoma pathogenesis. However, the post-translational mechanisms of EZH2 regulation are not completely understood. Here we show that EZH2 is a novel interactor and substrate of the SCF E3 ubiquitin ligase β-TrCP (FBXW1). β-TrCP ubiquitinates EZH2 and Jak2-mediated phosphorylation on Y641 directs β-TrCP-mediated EZH2 degradation. RNA interference-mediated silencing of β-TrCP or inhibition of Jak2 results in EZH2 stabilization with attendant increase in H3K27 trimethylation activity. Importantly, the EZH2(Y641) mutants recurrently implicated in lymphoma pathogenesis are unable to bind β-TrCP. Further, endogenous EZH2(Y641) mutants in lymphoma cells exhibit increased EZH2 stability and H3K27me3 hyperactivity. Our studies demonstrate that β-TrCP has an important role in controlling H3K27 trimethylation activity and lymphoma pathogenesis by targeting EZH2 for degradation.
Collapse
|
100
|
Marchesi I, Giordano A, Bagella L. Roles of enhancer of zeste homolog 2: from skeletal muscle differentiation to rhabdomyosarcoma carcinogenesis. Cell Cycle 2014; 13:516-27. [PMID: 24496329 DOI: 10.4161/cc.27921] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Polycomb group proteins represent a global silencing system involved in embryonic development and stem-cell maintenance that regulates the transition from proliferation to differentiation during organogenesis. Two main complexes have been discovered: the polycomb repressive complex (PRC) 1 and 2, able to induce gene silencing by a synergistic mechanism or independently by each other. Enhancer of zeste homolog 2 (EZH2), the catalytic subunit of PRC2, represses gene transcription through the tri-methylation of histone H3 lysine 27. EZH2 deregulation is frequently associated with tumorigenesis, metastatic character, and poor prognosis in various cancer types. This review explores the role of EZH2 in normal development and in carcinogenesis. We reviewed the polycomb-mediated silencing mechanisms, the regulation of EZH2 activity and its recruitment to target genes. We also analyzed the role of EZH2 in normal muscle differentiation and in rhabdomyosarcoma, considering EZH2 blockade as a new strategy for developing specific therapies.
Collapse
Affiliation(s)
- Irene Marchesi
- Department of Biomedical Sciences; Division of Biochemistry and National Institute of Biostructures and Biosystems; University of Sassari; Sassari, Italy
| | - Antonio Giordano
- Sbarro Institute for Cancer Research and Molecular Medicine; Center for Biotechnology; College of Science and Technology; Temple University; Philadelphia, PA USA; Human Pathology and Oncology Department; University of Siena; Siena, Italy
| | - Luigi Bagella
- Department of Biomedical Sciences; Division of Biochemistry and National Institute of Biostructures and Biosystems; University of Sassari; Sassari, Italy; Sbarro Institute for Cancer Research and Molecular Medicine; Center for Biotechnology; College of Science and Technology; Temple University; Philadelphia, PA USA
| |
Collapse
|