1
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Chen X, Ye Y, Gu L, Sun J, Du Y, Liu WJ, Li W, Zhang X, Jiang C. H3K27me3 Signal in the Cis Regulatory Elements Reveals the Differentiation Potential of Progenitors During Drosophila Neuroglial Development. GENOMICS PROTEOMICS & BIOINFORMATICS 2019; 17:297-304. [PMID: 31195140 PMCID: PMC6818177 DOI: 10.1016/j.gpb.2018.12.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Revised: 10/14/2018] [Accepted: 12/14/2018] [Indexed: 01/24/2023]
Abstract
Drosophila neural development undergoes extensive chromatin remodeling and precise epigenetic regulation. However, the roles of chromatin remodeling in establishment and maintenance of cell identity during cell fate transition remain enigmatic. Here, we compared the changes in gene expression, as well as the dynamics of nucleosome positioning and key histone modifications between the four major neural cell types during Drosophila neural development. We find that the neural progenitors can be separated from the terminally differentiated cells based on their gene expression profiles, whereas nucleosome distribution in the flanking regions of transcription start sites fails to identify the relationships between the progenitors and the differentiated cells. H3K27me3 signal in promoters and enhancers can not only distinguish the progenitors from the differentiated cells but also identify the differentiation path of the neural stem cells (NSCs) to the intermediate progenitor cells to the glial cells. In contrast, H3K9ac signal fails to identify the differentiation path, although it activates distinct sets of genes with neuron-specific and glia-related functions during the differentiation of the NSCs into neurons and glia, respectively. Together, our study provides novel insights into the crucial roles of chromatin remodeling in determining cell type during Drosophila neural development.
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Affiliation(s)
- Xiaolong Chen
- Institute of Translational Research, Tongji Hospital, School of Life Sciences and Technology, Shanghai Key Laboratory of Signaling and Disease Research, Tongji University, Shanghai 200092, China
| | - Youqiong Ye
- Institute of Translational Research, Tongji Hospital, School of Life Sciences and Technology, Shanghai Key Laboratory of Signaling and Disease Research, Tongji University, Shanghai 200092, China
| | - Liang Gu
- Institute of Translational Research, Tongji Hospital, School of Life Sciences and Technology, Shanghai Key Laboratory of Signaling and Disease Research, Tongji University, Shanghai 200092, China
| | - Jin Sun
- Institute of Translational Research, Tongji Hospital, School of Life Sciences and Technology, Shanghai Key Laboratory of Signaling and Disease Research, Tongji University, Shanghai 200092, China
| | - Yanhua Du
- Institute of Translational Research, Tongji Hospital, School of Life Sciences and Technology, Shanghai Key Laboratory of Signaling and Disease Research, Tongji University, Shanghai 200092, China
| | - Wen-Ju Liu
- Institute of Translational Research, Tongji Hospital, School of Life Sciences and Technology, Shanghai Key Laboratory of Signaling and Disease Research, Tongji University, Shanghai 200092, China
| | - Wei Li
- Tongji University Library, Tongji University, Shanghai 200092, China
| | - Xiaobai Zhang
- Institute of Translational Research, Tongji Hospital, School of Life Sciences and Technology, Shanghai Key Laboratory of Signaling and Disease Research, Tongji University, Shanghai 200092, China
| | - Cizhong Jiang
- Institute of Translational Research, Tongji Hospital, School of Life Sciences and Technology, Shanghai Key Laboratory of Signaling and Disease Research, Tongji University, Shanghai 200092, China; Research Center of Stem Cells and Ageing, Tsingtao Advanced Research Institute, Tongji University, Tsingtao 266071, China.
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2
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Nucleosome eviction along with H3K9ac deposition enhances Sox2 binding during human neuroectodermal commitment. Cell Death Differ 2017; 24:1121-1131. [PMID: 28475175 PMCID: PMC5442478 DOI: 10.1038/cdd.2017.62] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Revised: 03/28/2017] [Accepted: 03/31/2017] [Indexed: 02/06/2023] Open
Abstract
Neuroectoderm is an important neural precursor. However, chromatin remodeling and its epigenetic regulatory roles during the differentiation of human neuroectodermal cells (hNECs) from human embryonic stem cells (hESCs) remain largely unexplored. Here, we obtained hNECs through directed differentiation from hESCs, and determined chromatin states in the two cell types. Upon differentiation, H2A.Z-mediated nucleosome depletion leads to an open chromatin structure in promoters and upregulates expression of neuroectodermal genes. Increase in H3K9ac signals and decrease in H3K27me3 signals in promoters result in an active chromatin state and activate neuroectodermal genes. Conversely, decrease in H3K9ac signals and increase in H3K27me3 signals in promoters repress pluripotency genes. Moreover, H3K9ac signals facilitate the pluripotency factor Sox2 binding to target sites unique to hNECs. Knockdown of the acetyltransferase Kat2b erases H3K9ac signals, disrupts Sox2 binding, and fails the differentiation. Our results demonstrate a hierarchy of epigenetic regulation of gene expression during the differentiation of hNECs from hESCs through chromatin remodeling.
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3
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Xi X, Lu L, Zhuge CC, Chen X, Zhai Y, Cheng J, Mao H, Yang CC, Tan BCM, Lee YN, Chien CT, Ho MS. The hypoparathyroidism-associated mutation in Drosophila Gcm compromises protein stability and glial cell formation. Sci Rep 2017; 7:39856. [PMID: 28051179 PMCID: PMC5209662 DOI: 10.1038/srep39856] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Accepted: 11/29/2016] [Indexed: 01/05/2023] Open
Abstract
Differentiated neurons and glia are acquired from immature precursors via transcriptional controls exerted by factors such as proteins in the family of Glial Cells Missing (Gcm). Mammalian Gcm proteins mediate neural stem cell induction, placenta and parathyroid development, whereas Drosophila Gcm proteins act as a key switch to determine neuronal and glial cell fates and regulate hemocyte development. The present study reports a hypoparathyroidism-associated mutation R59L that alters Drosophila Gcm (Gcm) protein stability, rendering it unstable, and hyperubiquitinated via the ubiquitin-proteasome system (UPS). GcmR59L interacts with the Slimb-based SCF complex and Protein Kinase C (PKC), which possibly plays a role in its phosphorylation, hence altering ubiquitination. Additionally, R59L causes reduced Gcm protein levels in a manner independent of the PEST domain signaling protein turnover. GcmR59L proteins bind DNA, functionally activate transcription, and induce glial cells, yet at a less efficient level. Finally, overexpression of either wild-type human Gcmb (hGcmb) or hGcmb carrying the conserved hypoparathyroidism mutation only slightly affects gliogenesis, indicating differential regulatory mechanisms in human and flies. Taken together, these findings demonstrate the significance of this disease-associated mutation in controlling Gcm protein stability via UPS, hence advance our understanding on how glial formation is regulated.
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Affiliation(s)
- Xiao Xi
- Research Center for Translational Medicine, Shanghai East Hospital, Tongji University School of Medicine, No. 150 Jimo Road, Shanghai 200120, China.,Key Laboratory of Arrhythmias of the Ministry of Education of China, Shanghai East Hospital, Tongji University School of Medicine, No. 150 Jimo Road, Shanghai 200120, China.,Department of Anatomy and Neurobiology, 1239 Siping Road, Tongji University School of Medicine, Shanghai, 200092, China
| | - Lu Lu
- Research Center for Translational Medicine, Shanghai East Hospital, Tongji University School of Medicine, No. 150 Jimo Road, Shanghai 200120, China.,Key Laboratory of Arrhythmias of the Ministry of Education of China, Shanghai East Hospital, Tongji University School of Medicine, No. 150 Jimo Road, Shanghai 200120, China.,Department of Anatomy and Neurobiology, 1239 Siping Road, Tongji University School of Medicine, Shanghai, 200092, China
| | - Chun-Chun Zhuge
- Research Center for Translational Medicine, Shanghai East Hospital, Tongji University School of Medicine, No. 150 Jimo Road, Shanghai 200120, China.,Key Laboratory of Arrhythmias of the Ministry of Education of China, Shanghai East Hospital, Tongji University School of Medicine, No. 150 Jimo Road, Shanghai 200120, China.,Department of Anatomy and Neurobiology, 1239 Siping Road, Tongji University School of Medicine, Shanghai, 200092, China
| | - Xuebing Chen
- Research Center for Translational Medicine, Shanghai East Hospital, Tongji University School of Medicine, No. 150 Jimo Road, Shanghai 200120, China.,Key Laboratory of Arrhythmias of the Ministry of Education of China, Shanghai East Hospital, Tongji University School of Medicine, No. 150 Jimo Road, Shanghai 200120, China.,Department of Anatomy and Neurobiology, 1239 Siping Road, Tongji University School of Medicine, Shanghai, 200092, China
| | - Yuanfen Zhai
- Research Center for Translational Medicine, Shanghai East Hospital, Tongji University School of Medicine, No. 150 Jimo Road, Shanghai 200120, China.,Key Laboratory of Arrhythmias of the Ministry of Education of China, Shanghai East Hospital, Tongji University School of Medicine, No. 150 Jimo Road, Shanghai 200120, China.,Department of Anatomy and Neurobiology, 1239 Siping Road, Tongji University School of Medicine, Shanghai, 200092, China
| | - Jingjing Cheng
- Research Center for Translational Medicine, Shanghai East Hospital, Tongji University School of Medicine, No. 150 Jimo Road, Shanghai 200120, China.,Key Laboratory of Arrhythmias of the Ministry of Education of China, Shanghai East Hospital, Tongji University School of Medicine, No. 150 Jimo Road, Shanghai 200120, China.,Department of Anatomy and Neurobiology, 1239 Siping Road, Tongji University School of Medicine, Shanghai, 200092, China
| | - Haian Mao
- Research Center for Translational Medicine, Shanghai East Hospital, Tongji University School of Medicine, No. 150 Jimo Road, Shanghai 200120, China.,Key Laboratory of Arrhythmias of the Ministry of Education of China, Shanghai East Hospital, Tongji University School of Medicine, No. 150 Jimo Road, Shanghai 200120, China.,Department of Anatomy and Neurobiology, 1239 Siping Road, Tongji University School of Medicine, Shanghai, 200092, China
| | - Chang-Ching Yang
- Department of Biomedical Sciences and Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Kwei-San, Tao-Yuan, Taiwan
| | - Bertrand Chin-Ming Tan
- Department of Biomedical Sciences and Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Kwei-San, Tao-Yuan, Taiwan
| | - Yi-Nan Lee
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | | | - Margaret S Ho
- Research Center for Translational Medicine, Shanghai East Hospital, Tongji University School of Medicine, No. 150 Jimo Road, Shanghai 200120, China.,Key Laboratory of Arrhythmias of the Ministry of Education of China, Shanghai East Hospital, Tongji University School of Medicine, No. 150 Jimo Road, Shanghai 200120, China.,Department of Anatomy and Neurobiology, 1239 Siping Road, Tongji University School of Medicine, Shanghai, 200092, China
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4
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Ye Y, Li M, Gu L, Chen X, Shi J, Zhang X, Jiang C. Chromatin remodeling during in vivo neural stem cells differentiating to neurons in early Drosophila embryos. Cell Death Differ 2016; 24:409-420. [PMID: 27858939 PMCID: PMC5344203 DOI: 10.1038/cdd.2016.135] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2016] [Revised: 10/06/2016] [Accepted: 10/18/2016] [Indexed: 12/25/2022] Open
Abstract
Neurons are a key component of the nervous system and differentiate from multipotent neural stem cells (NSCs). Chromatin remodeling has a critical role in the differentiation process. However, its in vivo epigenetic regulatory role remains unknown. We show here that nucleosome depletion regions (NDRs) form in both proximal promoters and distal enhancers during NSCs differentiating into neurons in the early Drosophila embryonic development. NDR formation in the regulatory regions involves nucleosome shift and eviction. Nucleosome occupancy in promoter NDRs is inversely proportional to the gene activity. Genes with promoter NDR formation during differentiation are enriched for functions related to neuron development and maturation. Active histone-modification signals (H3K4me3 and H3K9ac) in promoters are gained in neurons in two modes: de novo establishment to high levels or increase from the existing levels in NSCs. The gene sets corresponding to the two modes have different neuron-related functions. Dynamic changes of H3K27ac and H3K9ac signals in enhancers and promoters synergistically repress genes associated with neural stem or progenitor cell-related pluripotency and upregulate genes associated with neuron projection morphogenesis, neuron differentiation, and so on. Our results offer new insights into chromatin remodeling during in vivo neuron development and lay a foundation for its epigenetic regulatory mechanism study of other lineage specification.
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Affiliation(s)
- Youqiong Ye
- Department of Clinical Laboratory Medicine, Shanghai Tenth People's Hospital of Tongji University, Shanghai Key Laboratory of Signaling and Disease Research, The School of Life Sciences and Technology, The Collaborative Innovation Center for Brain Science, Tongji University, Shanghai 200092, China
| | - Min Li
- Department of Clinical Laboratory Medicine, Shanghai Tenth People's Hospital of Tongji University, Shanghai Key Laboratory of Signaling and Disease Research, The School of Life Sciences and Technology, The Collaborative Innovation Center for Brain Science, Tongji University, Shanghai 200092, China
| | - Liang Gu
- Department of Clinical Laboratory Medicine, Shanghai Tenth People's Hospital of Tongji University, Shanghai Key Laboratory of Signaling and Disease Research, The School of Life Sciences and Technology, The Collaborative Innovation Center for Brain Science, Tongji University, Shanghai 200092, China
| | - Xiaolong Chen
- Department of Clinical Laboratory Medicine, Shanghai Tenth People's Hospital of Tongji University, Shanghai Key Laboratory of Signaling and Disease Research, The School of Life Sciences and Technology, The Collaborative Innovation Center for Brain Science, Tongji University, Shanghai 200092, China
| | - Jiejun Shi
- Department of Clinical Laboratory Medicine, Shanghai Tenth People's Hospital of Tongji University, Shanghai Key Laboratory of Signaling and Disease Research, The School of Life Sciences and Technology, The Collaborative Innovation Center for Brain Science, Tongji University, Shanghai 200092, China
| | - Xiaobai Zhang
- Department of Clinical Laboratory Medicine, Shanghai Tenth People's Hospital of Tongji University, Shanghai Key Laboratory of Signaling and Disease Research, The School of Life Sciences and Technology, The Collaborative Innovation Center for Brain Science, Tongji University, Shanghai 200092, China
| | - Cizhong Jiang
- Department of Clinical Laboratory Medicine, Shanghai Tenth People's Hospital of Tongji University, Shanghai Key Laboratory of Signaling and Disease Research, The School of Life Sciences and Technology, The Collaborative Innovation Center for Brain Science, Tongji University, Shanghai 200092, China
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5
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Chromatin remodeling during the in vivo glial differentiation in early Drosophila embryos. Sci Rep 2016; 6:33422. [PMID: 27634414 PMCID: PMC5025732 DOI: 10.1038/srep33422] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Accepted: 08/26/2016] [Indexed: 12/31/2022] Open
Abstract
Chromatin remodeling plays a critical role in gene regulation and impacts many biological processes. However, little is known about the relationship between chromatin remodeling dynamics and in vivo cell lineage commitment. Here, we reveal the patterns of histone modification change and nucleosome positioning dynamics and their epigenetic regulatory roles during the in vivo glial differentiation in early Drosophila embryos. The genome-wide average H3K9ac signals in promoter regions are decreased in the glial cells compared to the neural progenitor cells. However, H3K9ac signals are increased in a group of genes that are up-regulated in glial cells and involved in gliogenesis. There occurs extensive nucleosome remodeling including shift, loss, and gain. Nucleosome depletion regions (NDRs) form in both promoters and enhancers. As a result, the associated genes are up-regulated. Intriguingly, NDRs form in two fashions: nucleosome shift and eviction. Moreover, the mode of NDR formation is independent of the original chromatin state of enhancers in the neural progenitor cells.
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6
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Cattenoz PB, Giangrande A. Revisiting the role of the Gcm transcription factor, from master regulator to Swiss army knife. Fly (Austin) 2016; 10:210-8. [PMID: 27434165 DOI: 10.1080/19336934.2016.1212793] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Master genes are known to induce the differentiation of a multipotent cell into a specific cell type. These molecules are often transcription factors that switch on the regulatory cascade that triggers cell specification. Gcm was first described as the master gene of the glial fate in Drosophila as it induces the differentiation of neuroblasts into glia in the developing nervous system. Later on, Gcm was also shown to regulate the differentiation of blood, tendon and peritracheal cells as well as that of neuronal subsets. Thus, the glial master gene is used in at least 4 additional systems to promote differentiation. To understand the numerous roles of Gcm, we recently reported a genome-wide screen of Gcm direct targets in the Drosophila embryo. This screen provided new insight into the role and mode of action of this powerful transcription factor, notably on the interactions between Gcm and major differentiation pathways such as the Hedgehog, Notch and JAK/STAT. Here, we discuss the mode of action of Gcm in the different systems, we present new tissues that require Gcm and we revise the concept of 'master gene'.
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Affiliation(s)
- Pierre B Cattenoz
- a Department of Functional Genomics and Cancer , Institut de Génétique et de Biologie Moléculaire et Cellulaire , Illkirch , France
| | - Angela Giangrande
- a Department of Functional Genomics and Cancer , Institut de Génétique et de Biologie Moléculaire et Cellulaire , Illkirch , France
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7
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Altenhein B, Cattenoz PB, Giangrande A. The early life of a fly glial cell. WILEY INTERDISCIPLINARY REVIEWS-DEVELOPMENTAL BIOLOGY 2015. [DOI: 10.1002/wdev.200] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
| | | | - Angela Giangrande
- Department of Functional Genomics and Cancer; IGBMC; Illkirch France
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8
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Glial cells in neuronal development: recent advances and insights from Drosophila melanogaster. Neurosci Bull 2015; 30:584-94. [PMID: 25015062 DOI: 10.1007/s12264-014-1448-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2014] [Accepted: 05/22/2014] [Indexed: 12/30/2022] Open
Abstract
Glia outnumber neurons and are the most abundant cell type in the nervous system. Whereas neurons are the major carriers, transducers, and processors of information, glial cells, once considered mainly to play a passive supporting role, are now recognized for their active contributions to almost every aspect of nervous system development. Recently, insights from the invertebrate organism Drosophila melanogaster have advanced our knowledge of glial cell biology. In particular, findings on neuron-glia interactions via intrinsic and extrinsic mechanisms have shed light on the importance of glia during different stages of neuronal development. Here, we summarize recent advances in understanding the functions of Drosophila glia, which resemble their mammalian counterparts in morphology and function, neural stem-cell conversion, synapse formation, and developmental axon pruning. These discoveries reinforce the idea that glia are substantial players in the developing nervous system and further advance the understanding of mechanisms leading to neurodegeneration.
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9
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Sorokin EP, Gasch AP, Kimble J. Competence for chemical reprogramming of sexual fate correlates with an intersexual molecular signature in Caenorhabditis elegans. Genetics 2014; 198:561-75. [PMID: 25146970 PMCID: PMC4196613 DOI: 10.1534/genetics.114.169409] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2014] [Accepted: 08/10/2014] [Indexed: 01/24/2023] Open
Abstract
In multicellular organisms, genetic programs guide cells to adopt cell fates as tissues are formed during development, maintained in adults, and repaired after injury. Here we explore how a small molecule in the environment can switch a genetic program from one fate to another. Wild-type Caenorhabditis elegans XX adult hermaphrodites make oocytes continuously, but certain mutant XX adults make sperm instead in an otherwise hermaphrodite soma. Thus, puf-8; lip-1 XX adults make only sperm, but they can be switched from sperm to oocyte production by treatment with a small-molecule MEK inhibitor. To ask whether this chemical reprogramming is common, we tested six XX sperm-only mutants, but found only one other capable of cell fate switching, fbf-1; lip-1. Therefore, reprogramming competence relies on genotype, with only certain mutants capable of responding to the MEK inhibitor with a cell fate change. To gain insight into the molecular basis of competence for chemical reprogramming, we compared polyadenylated transcriptomes of competent and noncompetent XX sperm-only mutants in the absence of the MEK inhibitor and hence in the absence of cell fate reprogramming. Despite their cellular production of sperm, competent mutants were enriched for oogenic messenger RNAs relative to mutants lacking competence for chemical reprogramming. In addition, competent mutants expressed the oocyte-specific protein RME-2, whereas those lacking competence did not. Therefore, mutants competent for reprogramming possess an intersexual molecular profile at both RNA and protein levels. We suggest that this intersexual molecular signature is diagnostic of an intermediate network state that poises the germline tissue for changing its cellular fate in response to environmental cues.
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Affiliation(s)
- Elena P Sorokin
- Graduate Program in Cellular and Molecular Biology, University of Wisconsin, Madison, Wisconsin 53706
| | - Audrey P Gasch
- Laboratory of Genetics, University of Wisconsin, Madison, Wisconsin 53706
| | - Judith Kimble
- Laboratory of Genetics, University of Wisconsin, Madison, Wisconsin 53706 Department of Biochemistry, University of Wisconsin, Madison, Wisconsin 53706 Howard Hughes Medical Institute, University of Wisconsin, Madison, Wisconsin 53706
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10
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Interlocked loops trigger lineage specification and stable fates in the Drosophila nervous system. Nat Commun 2014; 5:4484. [DOI: 10.1038/ncomms5484] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2014] [Accepted: 06/23/2014] [Indexed: 11/09/2022] Open
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11
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Alkhori L, Öst A, Alenius M. The corepressor Atrophin specifies odorant receptor expression in Drosophila. FASEB J 2013; 28:1355-64. [PMID: 24334704 DOI: 10.1096/fj.13-240325] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
In both insects and vertebrates, each olfactory sensory neuron (OSN) expresses one odorant receptor (OR) from a large genomic repertoire. How a receptor is specified is a tantalizing question addressing fundamental aspects of cell differentiation. Here, we demonstrate that the corepressor Atrophin (Atro) segregates OR gene expression between OSN classes in Drosophila. We show that the knockdown of Atro result in either loss or gain of a broad set of ORs. Each OR phenotypic group correlated with one of two opposing Notch fates, Notch responding, Nba (N(on)), and nonresponding, Nab (N(off)) OSNs. Our data show that Atro segregates ORs expressed in the Nba OSN classes and helps establish the Nab fate during OSN development. Consistent with a role in recruiting histone deacetylates, immunohistochemistry revealed that Atro regulates global histone 3 acetylation (H3ac) in OSNs and requires Hdac3 to segregate OR gene expression. We further found that Nba OSN classes exhibit variable but higher H3ac levels than the Nab OSNs. Together, these data suggest that Atro determines the level of H3ac, which ensures correct OR gene expression within the Nba OSNs. We propose a mechanism by which a single corepressor can specify a large number of neuron classes.
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Affiliation(s)
- Liza Alkhori
- 1Department of Clinical and Experimental Medicine, Linköping University, S-581 83 Linköping, Sweden.
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12
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Cattenoz PB, Giangrande A. Lineage specification in the fly nervous system and evolutionary implications. Cell Cycle 2013; 12:2753-9. [PMID: 23966161 DOI: 10.4161/cc.25918] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Over the last decades, it has become clear that glia are multifunctional and plastic cells endowed with key regulatory roles. They control the response to developmental and/or pathological signals, thereby affecting neural proliferation, remodeling, survival, and regeneration. It is, therefore, important to understand the biology of these cells and the molecular mechanisms controlling their development/activity. The fly community has made major breakthroughs by characterizing the bases of gliogenesis and function. Here we describe the regulation and the role of the fly glial determinant. Then, we discuss the impact of the determinant in cell plasticity and differentiation. Finally, we address the conservation of this pathway across evolution.
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Affiliation(s)
- Pierre B Cattenoz
- Institut de Génétique et de Biologie Moléculaire et Cellulaire; IGBMC/CNRS/INSERM/UDS; Strasbourg, France
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13
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Coutinho-Budd J, Freeman MR. Probing the enigma: unraveling glial cell biology in invertebrates. Curr Opin Neurobiol 2013; 23:1073-9. [PMID: 23896311 DOI: 10.1016/j.conb.2013.07.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2013] [Revised: 07/02/2013] [Accepted: 07/02/2013] [Indexed: 12/11/2022]
Abstract
Despite their predominance in the nervous system, the precise ways in which glial cells develop and contribute to overall neural function remain poorly defined in any organism. Investigations in simple model organisms have identified remarkable morphological, molecular, and functional similarities between invertebrate and vertebrate glial subtypes. Invertebrates like Drosophila and Caenorhabditis elegans offer an abundance of tools for in vivo genetic manipulation of single cells or whole populations of glia, ease of access to neural tissues throughout development, and the opportunity for forward genetic analysis of fundamental aspects of glial cell biology. These features suggest that invertebrate model systems have high potential for vastly improving the understanding of glial biology. This review highlights recent work in Drosophila and other invertebrates that reveal new insights into basic mechanisms involved in glial development.
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Affiliation(s)
- Jaeda Coutinho-Budd
- Neurobiology Department, University of Massachusetts Medical School, Worcester, MA 01605, United States
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14
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Laneve P, Delaporte C, Trebuchet G, Komonyi O, Flici H, Popkova A, D'Agostino G, Taglini F, Kerekes I, Giangrande A. The Gcm/Glide molecular and cellular pathway: new actors and new lineages. Dev Biol 2012; 375:65-78. [PMID: 23276603 DOI: 10.1016/j.ydbio.2012.12.014] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2012] [Revised: 11/18/2012] [Accepted: 12/14/2012] [Indexed: 12/21/2022]
Abstract
In Drosophila, the transcription factor Gcm/Glide plays a key role in cell fate determination and cellular differentiation. In light of its crucial biological impact, major efforts have been put for analyzing its properties as master regulator, from both structural and functional points of view. However, the lack of efficient antibodies specific to the Gcm/Glide protein precluded thorough analyses of its regulation and activity in vivo. In order to relieve such restraints, we designed an epitope-tagging approach to "FLAG"-recognize and analyze the functional protein both in vitro (exogenous Gcm/Glide) and in vivo (endogenous protein). We here (i) reveal a tight interconnection between the small RNA and the Gcm/Glide pathways. AGO1 and miR-1 are Gcm/Glide targets whereas miR-279 negatively controls Gcm/Glide expression (ii) identify a novel cell population, peritracheal cells, expressing and requiring Gcm/Glide. Peritracheal cells are non-neuronal neurosecretory cells that are essential in ecdysis. In addition to emphasizing the importance of following the distribution and the activity of endogenous proteins in vivo, this study provides new insights and a novel frame to understand the Gcm/Glide biology.
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Affiliation(s)
- Pietro Laneve
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch 67404, France
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15
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Popkova A, Bernardoni R, Diebold C, Van de Bor V, Schuettengruber B, González I, Busturia A, Cavalli G, Giangrande A. Polycomb controls gliogenesis by regulating the transient expression of the Gcm/Glide fate determinant. PLoS Genet 2012; 8:e1003159. [PMID: 23300465 PMCID: PMC3531469 DOI: 10.1371/journal.pgen.1003159] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2012] [Accepted: 10/26/2012] [Indexed: 11/19/2022] Open
Abstract
The Gcm/Glide transcription factor is transiently expressed and required in the Drosophila nervous system. Threshold Gcm/Glide levels control the glial versus neuronal fate choice, and its perdurance triggers excessive gliogenesis, showing that its tight and dynamic regulation ensures the proper balance between neurons and glia. Here, we present a genetic screen for potential gcm/glide interactors and identify genes encoding chromatin factors of the Trithorax and of the Polycomb groups. These proteins maintain the heritable epigenetic state, among others, of HOX genes throughout development, but their regulatory role on transiently expressed genes remains elusive. Here we show that Polycomb negatively affects Gcm/Glide autoregulation, a positive feedback loop that allows timely accumulation of Gcm/Glide threshold levels. Such temporal fine-tuning of gene expression tightly controls gliogenesis. This work performed at the levels of individual cells reveals an undescribed mode of Polycomb action in the modulation of transiently expressed fate determinants and hence in the acquisition of specific cell identity in the nervous system.
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Affiliation(s)
- Anna Popkova
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, CNRS/INSERM/UDS, Illkirch, France
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16
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Mao H, Lv Z, Ho MS. Gcm proteins function in the developing nervous system. Dev Biol 2012; 370:63-70. [PMID: 22842100 DOI: 10.1016/j.ydbio.2012.07.018] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2012] [Revised: 07/02/2012] [Accepted: 07/10/2012] [Indexed: 11/17/2022]
Abstract
A fundamental issue during nervous system development is how individual cells are formed from the undefined precursors. Differentiated neurons and glia, two major cell types mediating neuronal function, are acquired from immature precursors via a series of explicit controls exerted by transcription factors such as proteins in the family of Glial cells missing (Gcm). In mammals, Gcm proteins are involved in placenta and parathyroid gland development, whereas in the invertebrate organism Drosophila, Gcm proteins act as fate determinants for glial cell fate, regulate neural stem cell (NSC) induction and conversion, and promote glial proliferation. In particular, Gcm protein levels are carefully tuned for Drosophila gliogenesis and their stability is under precise control via the ubiquitin-proteasome system (UPS). Here we summarize recent advances on Gcm proteins function. In addition to describe various features of Gcm protein family, the significance of their functions in the developing nervous system is also discussed.
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Affiliation(s)
- Haian Mao
- Department of Nuclear Medicine, Shanghai Tenth Hospital, Tongji University, Shanghai 200072, China
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17
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Flici H, Giangrande A. Stem cell aging and plasticity in the Drosophila nervous system. Fly (Austin) 2012; 6:108-12. [PMID: 22634501 DOI: 10.4161/fly.19797] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The majority of neural stem cells (NSCs) are considered as very plastic precursors that, in vitro, can divide indefinitely or differentiate into neurons or glia under specific conditions. However, in vivo, these cells actively proliferate during development, and later enter quiescence or apoptosis. This raises the issue as to whether stem cells keep their plastic behavior throughout their life, which may impact their therapeutic potential in regenerative medicine. Using the Gcm/Glide (for Glial cell missing/Glial cell deficient) transcription factor, which is able to trigger a complete and stable fate conversion into glia when ectopically expressed, we recently reported that the plasticity of Drosophila NSCs, commonly called neuroblasts (NBs), is age-dependent. When challenged with Gcm/Glide, newborn NBs are more easily converted into glia than old ones. Furthermore, the few old NBs that can be converted frequently generate cells with a stable (NB/glia) intermediate identity, a phenotype characteristic of cancer cells. We here discuss the concept of aging in NSC fate conversion and speculate on how our findings impact the ongoing debate concerning NSC plasticity.
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Affiliation(s)
- Hakima Flici
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, CNRS/INSERM/UDS, Illkirch, France
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18
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Histone deacetylase inhibitors in cell pluripotency, differentiation, and reprogramming. Stem Cells Int 2012; 2012:184154. [PMID: 22550500 PMCID: PMC3328162 DOI: 10.1155/2012/184154] [Citation(s) in RCA: 88] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2011] [Accepted: 12/19/2011] [Indexed: 12/17/2022] Open
Abstract
Histone deacetylase inhibitors (HDACi) are small molecules that have important and pleiotropic effects on cell homeostasis. Under distinct developmental conditions, they can promote either self-renewal or differentiation of embryonic stem cells. In addition, they can promote directed differentiation of embryonic and tissue-specific stem cells along the neuronal, cardiomyocytic, and hepatic lineages. They have been used to facilitate embryo development following somatic cell nuclear transfer and induced pluripotent stem cell derivation by ectopic expression of pluripotency factors. In the latter method, these molecules not only increase effectiveness, but can also render the induction independent of the oncogenes c-Myc and Klf4. Here we review the molecular pathways that are involved in the functions of HDAC inhibitors on stem cell differentiation and reprogramming of somatic cells into pluripotency. Deciphering the mechanisms of HDAC inhibitor actions is very important to enable their exploitation for efficient and simple tissue regeneration therapies.
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19
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Jadasz JJ, Aigner L, Rivera FJ, Küry P. The remyelination Philosopher's Stone: stem and progenitor cell therapies for multiple sclerosis. Cell Tissue Res 2012; 349:331-47. [PMID: 22322424 DOI: 10.1007/s00441-012-1331-x] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2011] [Accepted: 01/16/2012] [Indexed: 12/12/2022]
Abstract
Multiple sclerosis (MS) is an autoimmune disease that leads to oligodendrocyte loss and subsequent demyelination of the adult central nervous system (CNS). The pathology is characterized by transient phases of recovery during which remyelination can occur as a result of resident oligodendroglial precursor and stem/progenitor cell activation. However, myelin repair efficiency remains low urging the development of new therapeutical approaches that promote remyelination activities. Current MS treatments target primarily the immune system in order to reduce the relapse rate and the formation of inflammatory lesions, whereas no therapies exist in order to regenerate damaged myelin sheaths. During the last few years, several transplantation studies have been conducted with adult neural stem/progenitor cells and glial precursor cells to evaluate their potential to generate mature oligodendrocytes that can remyelinate axons. In parallel, modulation of the endogenous progenitor niche by neural and mesenchymal stem cell transplantation with the aim of promoting CNS progenitor differentiation and myelination has been studied. Here, we summarize these findings and discuss the properties and consequences of the various molecular and cell-mediated remyelination approaches. Moreover, we address age-associated intrinsic cellular changes that might influence the regenerative outcome. We also evaluate the extent to which these experimental treatments might increase the regeneration capacity of the demyelinated human CNS and hence be turned into future therapies.
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Affiliation(s)
- Janusz J Jadasz
- Department of Neurology, Medical Faculty, Heinrich Heine University, Düsseldorf, Germany
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