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Abstract
Numerous examples of different phenotypic outcomes in response to varying environmental conditions have been described across phyla, from plants to mammals. Here, we examine the impact of the environment on different developmental traits, focusing in particular on one key environmental variable, nutrient availability. We present advances in our understanding of developmental plasticity in response to food variation using the nematode Caenorhabditis elegans, which provides a near-isogenic context while permitting lab-controlled environments and analysis of wild isolates. We discuss how this model has allowed investigators not only to describe developmental plasticity events at the organismal level but also to zoom in on the tissues involved in translating changes in the environment into a plastic response, as well as the underlying molecular pathways, and sometimes associated changes in behaviour. Lastly, we also discuss how early life starvation experiences can be logged to later impact adult physiological traits, and how such memory could be wired.
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Affiliation(s)
- Sophie Jarriault
- Université de Strasbourg, CNRS, Inserm, IGBMC, Development and Stem Cells Department, UMR 7104 - UMR-S 1258, F-67400 Illkirch, France
| | - Christelle Gally
- Université de Strasbourg, CNRS, Inserm, IGBMC, Development and Stem Cells Department, UMR 7104 - UMR-S 1258, F-67400 Illkirch, France
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2
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Medwig-Kinney TN, Kinney BA, Martinez MAQ, Yee C, Sirota SS, Mullarkey AA, Somineni N, Hippler J, Zhang W, Shen K, Hammell C, Pani AM, Matus DQ. Dynamic compartmentalization of the pro-invasive transcription factor NHR-67 reveals a role for Groucho in regulating a proliferative-invasive cellular switch in C. elegans. eLife 2023; 12:RP84355. [PMID: 38038410 PMCID: PMC10691804 DOI: 10.7554/elife.84355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2023] Open
Abstract
A growing body of evidence suggests that cell division and basement membrane invasion are mutually exclusive cellular behaviors. How cells switch between proliferative and invasive states is not well understood. Here, we investigated this dichotomy in vivo by examining two cell types in the developing Caenorhabditis elegans somatic gonad that derive from equipotent progenitors, but exhibit distinct cell behaviors: the post-mitotic, invasive anchor cell and the neighboring proliferative, non-invasive ventral uterine (VU) cells. We show that the fates of these cells post-specification are more plastic than previously appreciated and that levels of NHR-67 are important for discriminating between invasive and proliferative behavior. Transcription of NHR-67 is downregulated following post-translational degradation of its direct upstream regulator, HLH-2 (E/Daughterless) in VU cells. In the nuclei of VU cells, residual NHR-67 protein is compartmentalized into discrete punctae that are dynamic over the cell cycle and exhibit liquid-like properties. By screening for proteins that colocalize with NHR-67 punctae, we identified new regulators of uterine cell fate maintenance: homologs of the transcriptional co-repressor Groucho (UNC-37 and LSY-22), as well as the TCF/LEF homolog POP-1. We propose a model in which the association of NHR-67 with the Groucho/TCF complex suppresses the default invasive state in non-invasive cells, which complements transcriptional regulation to add robustness to the proliferative-invasive cellular switch in vivo.
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Affiliation(s)
- Taylor N Medwig-Kinney
- Department of Biochemistry and Cell Biology, Stony Brook UniversityStony BrookUnited States
| | - Brian A Kinney
- Cold Spring Harbor LaboratoryCold Spring HarborUnited States
| | - Michael AQ Martinez
- Department of Biochemistry and Cell Biology, Stony Brook UniversityStony BrookUnited States
| | - Callista Yee
- Howard Hughes Medical Institute, Department of Biology, Stanford UniversityStanfordUnited States
| | - Sydney S Sirota
- Department of Biochemistry and Cell Biology, Stony Brook UniversityStony BrookUnited States
| | - Angelina A Mullarkey
- Department of Biochemistry and Cell Biology, Stony Brook UniversityStony BrookUnited States
| | - Neha Somineni
- Department of Biochemistry and Cell Biology, Stony Brook UniversityStony BrookUnited States
| | - Justin Hippler
- Department of Biochemistry and Cell Biology, Stony Brook UniversityStony BrookUnited States
- Science and Technology Research Program, Smithtown High School EastSt. JamesUnited States
| | - Wan Zhang
- Department of Biochemistry and Cell Biology, Stony Brook UniversityStony BrookUnited States
| | - Kang Shen
- Howard Hughes Medical Institute, Department of Biology, Stanford UniversityStanfordUnited States
| | | | - Ariel M Pani
- Departments of Biology and Cell Biology, University of VirginiaCharlottesvilleUnited States
| | - David Q Matus
- Department of Biochemistry and Cell Biology, Stony Brook UniversityStony BrookUnited States
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3
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Özcan I, Tursun B. Identifying Molecular Roadblocks for Transcription Factor-Induced Cellular Reprogramming In Vivo by Using C. elegans as a Model Organism. J Dev Biol 2023; 11:37. [PMID: 37754839 PMCID: PMC10531806 DOI: 10.3390/jdb11030037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Revised: 08/18/2023] [Accepted: 08/29/2023] [Indexed: 09/28/2023] Open
Abstract
Generating specialized cell types via cellular transcription factor (TF)-mediated reprogramming has gained high interest in regenerative medicine due to its therapeutic potential to repair tissues and organs damaged by diseases or trauma. Organ dysfunction or improper tissue functioning might be restored by producing functional cells via direct reprogramming, also known as transdifferentiation. Regeneration by converting the identity of available cells in vivo to the desired cell fate could be a strategy for future cell replacement therapies. However, the generation of specific cell types via reprogramming is often restricted due to cell fate-safeguarding mechanisms that limit or even block the reprogramming of the starting cell type. Nevertheless, efficient reprogramming to generate homogeneous cell populations with the required cell type's proper molecular and functional identity is critical. Incomplete reprogramming will lack therapeutic potential and can be detrimental as partially reprogrammed cells may acquire undesired properties and develop into tumors. Identifying and evaluating molecular barriers will improve reprogramming efficiency to reliably establish the target cell identity. In this review, we summarize how using the nematode C. elegans as an in vivo model organism identified molecular barriers of TF-mediated reprogramming. Notably, many identified molecular factors have a high degree of conservation and were subsequently shown to block TF-induced reprogramming of mammalian cells.
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Affiliation(s)
- Ismail Özcan
- Department of Biology, Institute of Cell and Systems Biology of Animals, University of Hamburg, 20146 Hamburg, Germany
| | - Baris Tursun
- Department of Biology, Institute of Cell and Systems Biology of Animals, University of Hamburg, 20146 Hamburg, Germany
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4
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Dai CY, Ng CC, Hung GCC, Kirmes I, Hughes LA, Du Y, Brosnan CA, Ahier A, Hahn A, Haynes CM, Rackham O, Filipovska A, Zuryn S. ATFS-1 counteracts mitochondrial DNA damage by promoting repair over transcription. Nat Cell Biol 2023; 25:1111-1120. [PMID: 37460695 DOI: 10.1038/s41556-023-01192-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Accepted: 06/19/2023] [Indexed: 08/12/2023]
Abstract
The ability to balance conflicting functional demands is critical for ensuring organismal survival. The transcription and repair of the mitochondrial genome (mtDNA) requires separate enzymatic activities that can sterically compete1, suggesting a life-long trade-off between these two processes. Here in Caenorhabditis elegans, we find that the bZIP transcription factor ATFS-1/Atf5 (refs. 2,3) regulates this balance in favour of mtDNA repair by localizing to mitochondria and interfering with the assembly of the mitochondrial pre-initiation transcription complex between HMG-5/TFAM and RPOM-1/mtRNAP. ATFS-1-mediated transcriptional inhibition decreases age-dependent mtDNA molecular damage through the DNA glycosylase NTH-1/NTH1, as well as the helicase TWNK-1/TWNK, resulting in an enhancement in the functional longevity of cells and protection against decline in animal behaviour caused by targeted and severe mtDNA damage. Together, our findings reveal that ATFS-1 acts as a molecular focal point for the control of balance between genome expression and maintenance in the mitochondria.
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Affiliation(s)
- Chuan-Yang Dai
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, Queensland, Australia
| | - Chai Chee Ng
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, Queensland, Australia
| | - Grace Ching Ching Hung
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, Queensland, Australia
| | - Ina Kirmes
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, Queensland, Australia
| | - Laetitia A Hughes
- Harry Perkins Institute of Medical Research, QEII Medical Centre, The University of Western Australia, Nedlands, Western Australia, Australia
- ARC Centre of Excellence in Synthetic Biology, QEII Medical Centre, The University of Western Australia, Nedlands, Western Australia, Australia
- Telethon Kids Institute, Northern Entrance, Perth Children's Hospital, Nedlands, Western Australia, Australia
| | - Yunguang Du
- Department of Molecular, Cell and Cancer Biology, UMass Chan Medical School, Worchester, MA, USA
| | - Christopher A Brosnan
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, Queensland, Australia
| | - Arnaud Ahier
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, Queensland, Australia
| | - Anne Hahn
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, Queensland, Australia
| | - Cole M Haynes
- Department of Molecular, Cell and Cancer Biology, UMass Chan Medical School, Worchester, MA, USA
| | - Oliver Rackham
- Harry Perkins Institute of Medical Research, QEII Medical Centre, The University of Western Australia, Nedlands, Western Australia, Australia
- ARC Centre of Excellence in Synthetic Biology, QEII Medical Centre, The University of Western Australia, Nedlands, Western Australia, Australia
- Telethon Kids Institute, Northern Entrance, Perth Children's Hospital, Nedlands, Western Australia, Australia
- Curtin Medical School and Curtin Health Innovation Research Institute, Curtin University, Bentley, Western Australia, Australia
| | - Aleksandra Filipovska
- Harry Perkins Institute of Medical Research, QEII Medical Centre, The University of Western Australia, Nedlands, Western Australia, Australia
- ARC Centre of Excellence in Synthetic Biology, QEII Medical Centre, The University of Western Australia, Nedlands, Western Australia, Australia
- Telethon Kids Institute, Northern Entrance, Perth Children's Hospital, Nedlands, Western Australia, Australia
| | - Steven Zuryn
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, Queensland, Australia.
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Lup SD, Navarro-Quiles C, Micol JL. Versatile mapping-by-sequencing with Easymap v.2. FRONTIERS IN PLANT SCIENCE 2023; 14:1042913. [PMID: 36778692 PMCID: PMC9909543 DOI: 10.3389/fpls.2023.1042913] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Accepted: 01/04/2023] [Indexed: 06/18/2023]
Abstract
Mapping-by-sequencing combines Next Generation Sequencing (NGS) with classical genetic mapping by linkage analysis to establish gene-to-phenotype relationships. Although numerous tools have been developed to analyze NGS datasets, only a few are available for mapping-by-sequencing. One such tool is Easymap, a versatile, easy-to-use package that performs automated mapping of point mutations and large DNA insertions. Here, we describe Easymap v.2, which also maps small insertion/deletions (InDels), and includes workflows to perform QTL-seq and variant density mapping analyses. Each mapping workflow can accommodate different experimental designs, including outcrossing and backcrossing, F2, M2, and M3 mapping populations, chemically induced mutation and natural variant mapping, input files containing single-end or paired-end reads of genomic or complementary DNA sequences, and alternative control sample files in FASTQ and VCF formats. Easymap v.2 can also be used as a variant analyzer in the absence of a mapping algorithm and includes a multi-threading option.
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Rashid A, Tevlin M, Lu Y, Shaham S. A developmental pathway for epithelial-to-motoneuron transformation in C. elegans. Cell Rep 2022; 40:111414. [PMID: 36170838 PMCID: PMC9579992 DOI: 10.1016/j.celrep.2022.111414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 07/18/2022] [Accepted: 09/01/2022] [Indexed: 11/24/2022] Open
Abstract
Motoneurons and motoneuron-like pancreatic β cells arise from radial glia and ductal cells, respectively, both tube-lining progenitors that share molecular regulators. To uncover programs underlying motoneuron formation, we studied a similar, cell-division-independent transformation of the C. elegans tube-lining Y cell into the PDA motoneuron. We find that lin-12/Notch acts through ngn-1/Ngn and its regulator hlh-16/Olig to control transformation timing. lin-12 loss blocks transformation, while lin-12(gf) promotes precocious PDA formation. Early basal expression of ngn-1/Ngn and hlh-16/Olig depends on sem-4/Sall and egl-5/Hox. Later, coincident with Y cell morphological changes, ngn-1/Ngn expression is upregulated in a sem-4/Sall and egl-5/Hox-dependent but hlh-16/Olig-independent manner. Subsequently, Y cell retrograde extension forms an anchored process priming PDA axon extension. Extension requires ngn-1-dependent expression of the cytoskeleton organizers UNC-119, UNC-44/ANK, and UNC-33/CRMP, which also activate PDA terminal-gene expression. Our findings uncover cell-division-independent regulatory events leading to motoneuron generation, suggesting a conserved pathway for epithelial-to-motoneuron/motoneuron-like cell differentiation. Rashid et al. report on a conserved epithelial-to-motoneuron transformation pathway in C. elegans requiring ngn-1/Ngn and hlh-16/Olig. lin-12/Notch regulates transformation timing through these genes, while ngn-1/Ngn and hlh-16/Olig expression levels are regulated by sem-4/Sall and egl-5/Hox. Unexpectedly, the cytoskeleton organizers UNC-119, UNC-44, and UNC-33, which are ngn-1/Ngn targets, promote motoneuron terminal identity.
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Affiliation(s)
- Alina Rashid
- Laboratory of Developmental Genetics, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA
| | - Maya Tevlin
- Laboratory of Developmental Genetics, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA
| | - Yun Lu
- Laboratory of Developmental Genetics, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA
| | - Shai Shaham
- Laboratory of Developmental Genetics, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA.
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Riva C, Hajduskova M, Gally C, Suman SK, Ahier A, Jarriault S. A natural transdifferentiation event involving mitosis is empowered by integrating signaling inputs with conserved plasticity factors. Cell Rep 2022; 40:111365. [PMID: 36130499 PMCID: PMC9513805 DOI: 10.1016/j.celrep.2022.111365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 04/09/2022] [Accepted: 08/25/2022] [Indexed: 11/03/2022] Open
Abstract
Transdifferentiation, or direct cell reprogramming, is the conversion of one fully differentiated cell type into another. Whether core mechanisms are shared between natural transdifferentiation events when occurring with or without cell division is unclear. We have previously characterized the Y-to-PDA natural transdifferentiation in Caenorhabditis elegans, which occurs without cell division and requires orthologs of vertebrate reprogramming factors. Here, we identify a rectal-to-GABAergic transdifferentiation and show that cell division is required but not sufficient for conversion. We find shared mechanisms, including erasure of the initial identity, which requires the conserved reprogramming factors SEM-4/SALL, SOX-2, CEH-6/OCT, and EGL-5/HOX. We also find three additional and parallel roles of the Wnt signaling pathway: selection of a specific daughter, removal of the initial identity, and imposition of the precise final subtype identity. Our results support a model in which levels and antagonistic activities of SOX-2 and Wnt signaling provide a timer for the acquisition of final identity.
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Affiliation(s)
- Claudia Riva
- Development and Stem Cells Department, IGBMC, CNRS UMR 7104, Inserm U 1258, Université de Strasbourg, 67400 Illkirch, France
| | - Martina Hajduskova
- Development and Stem Cells Department, IGBMC, CNRS UMR 7104, Inserm U 1258, Université de Strasbourg, 67400 Illkirch, France
| | - Christelle Gally
- Development and Stem Cells Department, IGBMC, CNRS UMR 7104, Inserm U 1258, Université de Strasbourg, 67400 Illkirch, France.
| | - Shashi Kumar Suman
- Development and Stem Cells Department, IGBMC, CNRS UMR 7104, Inserm U 1258, Université de Strasbourg, 67400 Illkirch, France
| | - Arnaud Ahier
- Development and Stem Cells Department, IGBMC, CNRS UMR 7104, Inserm U 1258, Université de Strasbourg, 67400 Illkirch, France
| | - Sophie Jarriault
- Development and Stem Cells Department, IGBMC, CNRS UMR 7104, Inserm U 1258, Université de Strasbourg, 67400 Illkirch, France.
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8
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Neural Pericytes: A genomic archival state programmed by CHromatin topology. Eur J Cell Biol 2022; 101:151211. [DOI: 10.1016/j.ejcb.2022.151211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 02/04/2022] [Accepted: 02/25/2022] [Indexed: 11/22/2022] Open
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9
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Brahma safeguards canalization of cardiac mesoderm differentiation. Nature 2022; 602:129-134. [PMID: 35082446 DOI: 10.1038/s41586-021-04336-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Accepted: 12/08/2021] [Indexed: 12/26/2022]
Abstract
Differentiation proceeds along a continuum of increasingly fate-restricted intermediates, referred to as canalization1,2. Canalization is essential for stabilizing cell fate, but the mechanisms that underlie robust canalization are unclear. Here we show that the BRG1/BRM-associated factor (BAF) chromatin-remodelling complex ATPase gene Brm safeguards cell identity during directed cardiogenesis of mouse embryonic stem cells. Despite the establishment of a well-differentiated precardiac mesoderm, Brm-/- cells predominantly became neural precursors, violating germ layer assignment. Trajectory inference showed a sudden acquisition of a non-mesodermal identity in Brm-/- cells. Mechanistically, the loss of Brm prevented de novo accessibility of primed cardiac enhancers while increasing the expression of neurogenic factor POU3F1, preventing the binding of the neural suppressor REST and shifting the composition of BRG1 complexes. The identity switch caused by the Brm mutation was overcome by increasing BMP4 levels during mesoderm induction. Mathematical modelling supports these observations and demonstrates that Brm deletion affects cell fate trajectory by modifying saddle-node bifurcations2. In the mouse embryo, Brm deletion exacerbated mesoderm-deleted Brg1-mutant phenotypes, severely compromising cardiogenesis, and reveals an in vivo role for Brm. Our results show that Brm is a compensable safeguard of the fidelity of mesoderm chromatin states, and support a model in which developmental canalization is not a rigid irreversible path, but a highly plastic trajectory.
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Rezaei-Lotfi S, Vujovic F, Simonian M, Hunter N, Farahani RM. Programmed genomic instability regulates neural transdifferentiation of human brain microvascular pericytes. Genome Biol 2021; 22:334. [PMID: 34886891 PMCID: PMC8656028 DOI: 10.1186/s13059-021-02555-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Accepted: 11/22/2021] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND Transdifferentiation describes transformation in vivo of specialized cells from one lineage into another. While there is extensive literature on forced induction of lineage reprogramming in vitro, endogenous mechanisms that govern transdifferentiation remain largely unknown. The observation that human microvascular pericytes transdifferentiate into neurons provided an opportunity to explore the endogenous molecular basis for lineage reprogramming. RESULTS We show that abrupt destabilization of the higher-order chromatin topology that chaperones lineage memory of pericytes is driven by transient global transcriptional arrest. This leads within minutes to localized decompression of the repressed competing higher-order chromatin topology and expression of pro-neural genes. Transition to neural lineage is completed by probabilistic induction of R-loops in key myogenic loci upon re-initiation of RNA polymerase activity, leading to depletion of the myogenic transcriptome and emergence of the neurogenic transcriptome. CONCLUSIONS These findings suggest that the global transcriptional landscape not only shapes the functional cellular identity of pericytes, but also stabilizes lineage memory by silencing the competing neural program within a repressed chromatin state.
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Affiliation(s)
- Saba Rezaei-Lotfi
- IDR/Westmead Institute for Medical Research, Westmead, NSW 2145 Australia
- School of Medical Sciences, Faculty of Medicine and Health, University of Sydney, Sydney, NSW 2006 Australia
| | - Filip Vujovic
- IDR/Westmead Institute for Medical Research, Westmead, NSW 2145 Australia
- School of Medical Sciences, Faculty of Medicine and Health, University of Sydney, Sydney, NSW 2006 Australia
| | - Mary Simonian
- IDR/Westmead Institute for Medical Research, Westmead, NSW 2145 Australia
| | - Neil Hunter
- IDR/Westmead Institute for Medical Research, Westmead, NSW 2145 Australia
| | - Ramin M. Farahani
- IDR/Westmead Institute for Medical Research, Westmead, NSW 2145 Australia
- School of Medical Sciences, Faculty of Medicine and Health, University of Sydney, Sydney, NSW 2006 Australia
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11
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Rapti G. A perspective on C. elegans neurodevelopment: from early visionaries to a booming neuroscience research. J Neurogenet 2021; 34:259-272. [PMID: 33446023 DOI: 10.1080/01677063.2020.1837799] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The formation of the nervous system and its striking complexity is a remarkable feat of development. C. elegans served as a unique model to dissect the molecular events in neurodevelopment, from its early visionaries to the current booming neuroscience community. Soon after being introduced as a model, C. elegans was mapped at the level of genes, cells, and synapses, providing the first metazoan with a complete cell lineage, sequenced genome, and connectome. Here, I summarize mechanisms underlying C. elegans neurodevelopment, from the generation and diversification of neural components to their navigation and connectivity. I point out recent noteworthy findings in the fields of glia biology, sex dimorphism and plasticity in neurodevelopment, highlighting how current research connects back to the pioneering studies by Brenner, Sulston and colleagues. Multifaceted investigations in model organisms, connecting genes to cell function and behavior, expand our mechanistic understanding of neurodevelopment while allowing us to formulate emerging questions for future discoveries.
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Affiliation(s)
- Georgia Rapti
- European Molecular Biology Laboratory, Unit of Developmental Biology, Heidelberg, Germany
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12
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Rawsthorne H, Calahorro F, Holden-Dye L, O’ Connor V, Dillon J. Investigating autism associated genes in C. elegans reveals candidates with a role in social behaviour. PLoS One 2021; 16:e0243121. [PMID: 34043629 PMCID: PMC8158995 DOI: 10.1371/journal.pone.0243121] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Accepted: 03/29/2021] [Indexed: 11/18/2022] Open
Abstract
Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterised by a triad of behavioural impairments and includes disruption in social behaviour. ASD has a clear genetic underpinning and hundreds of genes are implicated in its aetiology. However, how single penetrant genes disrupt activity of neural circuits which lead to affected behaviours is only beginning to be understood and less is known about how low penetrant genes interact to disrupt emergent behaviours. Investigations are well served by experimental approaches that allow tractable investigation of the underpinning genetic basis of circuits that control behaviours that operate in the biological domains that are neuro-atypical in autism. The model organism C. elegans provides an experimental platform to investigate the effect of genetic mutations on behavioural outputs including those that impact social biology. Here we use progeny-derived social cues that modulate C. elegans food leaving to assay genetic determinants of social behaviour. We used the SAFRI Gene database to identify C. elegans orthologues of human ASD associated genes. We identified a number of mutants that displayed selective deficits in response to progeny. The genetic determinants of this complex social behaviour highlight the important contribution of synaptopathy and implicates genes within cell signalling, epigenetics and phospholipid metabolism functional domains. The approach overlaps with a growing number of studies that investigate potential molecular determinants of autism in C. elegans. However, our use of a complex, sensory integrative, emergent behaviour provides routes to enrich new or underexplored biology with the identification of novel candidate genes with a definable role in social behaviour.
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Affiliation(s)
- Helena Rawsthorne
- School of Biological Sciences, Highfield Campus, University of Southampton, Southampton, United Kingdom
| | - Fernando Calahorro
- School of Biological Sciences, Highfield Campus, University of Southampton, Southampton, United Kingdom
| | - Lindy Holden-Dye
- School of Biological Sciences, Highfield Campus, University of Southampton, Southampton, United Kingdom
| | - Vincent O’ Connor
- School of Biological Sciences, Highfield Campus, University of Southampton, Southampton, United Kingdom
| | - James Dillon
- School of Biological Sciences, Highfield Campus, University of Southampton, Southampton, United Kingdom
- * E-mail:
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13
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Lambert J, Lloret-Fernández C, Laplane L, Poole RJ, Jarriault S. On the origins and conceptual frameworks of natural plasticity-Lessons from single-cell models in C. elegans. Curr Top Dev Biol 2021; 144:111-159. [PMID: 33992151 DOI: 10.1016/bs.ctdb.2021.03.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
How flexible are cell identities? This problem has fascinated developmental biologists for several centuries and can be traced back to Abraham Trembley's pioneering manipulations of Hydra to test its regeneration abilities in the 1700s. Since the cell theory in the mid-19th century, developmental biology has been dominated by a single framework in which embryonic cells are committed to specific cell fates, progressively and irreversibly acquiring their differentiated identities. This hierarchical, unidirectional and irreversible view of cell identity has been challenged in the past decades through accumulative evidence that many cell types are more plastic than previously thought, even in intact organisms. The paradigm shift introduced by such plasticity calls into question several other key traditional concepts, such as how to define a differentiated cell or more generally cellular identity, and has brought new concepts, such as distinct cellular states. In this review, we want to contribute to this representation by attempting to clarify the conceptual and theoretical frameworks of cell plasticity and identity. In the context of these new frameworks we describe here an atlas of natural plasticity of cell identity in C. elegans, including our current understanding of the cellular and molecular mechanisms at play. The worm further provides interesting cases at the borderlines of cellular plasticity that highlight the conceptual challenges still ahead. We then discuss a set of future questions and perspectives arising from the studies of natural plasticity in the worm that are shared with other reprogramming and plasticity events across phyla.
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Affiliation(s)
- Julien Lambert
- IGBMC, Development and Stem Cells Department, CNRS UMR7104, INSERM U1258, Université de Strasbourg, Strasbourg, France
| | - Carla Lloret-Fernández
- Department of Cell and Developmental Biology, University College London, London, United Kingdom
| | - Lucie Laplane
- CNRS UMR 8590, University Paris I Panthéon-Sorbonne, IHPST, Paris, France
| | - Richard J Poole
- Department of Cell and Developmental Biology, University College London, London, United Kingdom.
| | - Sophie Jarriault
- IGBMC, Development and Stem Cells Department, CNRS UMR7104, INSERM U1258, Université de Strasbourg, Strasbourg, France.
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14
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Ahier A, Suman SK, Jarriault S. Gene bashing of ceh-6 locus identifies genomic regions important for ceh-6 rectal cell expression and rescue of its mutant lethality. MICROPUBLICATION BIOLOGY 2020; 2020. [PMID: 33364555 PMCID: PMC7753896 DOI: 10.17912/micropub.biology.000339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Strong loss-of-function or null mutants can sometimes lead to a penetrant early lethality, impairing the study of these genes’ function. This is the case for the ceh-6 null mutant, which exhibits 100% penetrant lethality. Here, we describe how we used gene bashing to identify distinct regulatory regions in the ceh-6 locus. This allowed us to generate a ceh-6 null strain that is viable and still displays ceh-6 mutant Y-to-PDA transdifferentiation phenotype. Such strategy can be applied to many other mutants impacting viability.
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Affiliation(s)
- Arnaud Ahier
- IGBMC, Development and Stem Cells Department, CNRS UMR7104, INSERM U1258, Université de Strasbourg, Illkirch CU Strasbourg, 67404 France.,current address: Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, Australia
| | - Shashi Kumar Suman
- IGBMC, Development and Stem Cells Department, CNRS UMR7104, INSERM U1258, Université de Strasbourg, Illkirch CU Strasbourg, 67404 France
| | - Sophie Jarriault
- IGBMC, Development and Stem Cells Department, CNRS UMR7104, INSERM U1258, Université de Strasbourg, Illkirch CU Strasbourg, 67404 France
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15
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Molina-García L, Lloret-Fernández C, Cook SJ, Kim B, Bonnington RC, Sammut M, O'Shea JM, Gilbert SPR, Elliott DJ, Hall DH, Emmons SW, Barrios A, Poole RJ. Direct glia-to-neuron transdifferentiation gives rise to a pair of male-specific neurons that ensure nimble male mating. eLife 2020; 9:e48361. [PMID: 33138916 PMCID: PMC7609048 DOI: 10.7554/elife.48361] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Accepted: 10/02/2020] [Indexed: 12/20/2022] Open
Abstract
Sexually dimorphic behaviours require underlying differences in the nervous system between males and females. The extent to which nervous systems are sexually dimorphic and the cellular and molecular mechanisms that regulate these differences are only beginning to be understood. We reveal here a novel mechanism by which male-specific neurons are generated in Caenorhabditis elegans through the direct transdifferentiation of sex-shared glial cells. This glia-to-neuron cell fate switch occurs during male sexual maturation under the cell-autonomous control of the sex-determination pathway. We show that the neurons generated are cholinergic, peptidergic, and ciliated putative proprioceptors which integrate into male-specific circuits for copulation. These neurons ensure coordinated backward movement along the mate's body during mating. One step of the mating sequence regulated by these neurons is an alternative readjustment movement performed when intromission becomes difficult to achieve. Our findings reveal programmed transdifferentiation as a developmental mechanism underlying flexibility in innate behaviour.
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Affiliation(s)
- Laura Molina-García
- Department of Cell and Developmental Biology, University College LondonLondonUnited Kingdom
| | - Carla Lloret-Fernández
- Department of Cell and Developmental Biology, University College LondonLondonUnited Kingdom
| | - Steven J Cook
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of MedicineNew YorkUnited States
| | - Byunghyuk Kim
- Department of Genetics, Albert Einstein College of MedicineNew YorkUnited States
| | - Rachel C Bonnington
- Department of Cell and Developmental Biology, University College LondonLondonUnited Kingdom
| | - Michele Sammut
- Department of Cell and Developmental Biology, University College LondonLondonUnited Kingdom
| | - Jack M O'Shea
- Department of Cell and Developmental Biology, University College LondonLondonUnited Kingdom
| | - Sophie PR Gilbert
- Department of Cell and Developmental Biology, University College LondonLondonUnited Kingdom
| | - David J Elliott
- Department of Cell and Developmental Biology, University College LondonLondonUnited Kingdom
| | - David H Hall
- Department of Genetics, Albert Einstein College of MedicineNew YorkUnited States
| | - Scott W Emmons
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of MedicineNew YorkUnited States
- Department of Genetics, Albert Einstein College of MedicineNew YorkUnited States
| | - Arantza Barrios
- Department of Cell and Developmental Biology, University College LondonLondonUnited Kingdom
| | - Richard J Poole
- Department of Cell and Developmental Biology, University College LondonLondonUnited Kingdom
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16
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Harnessing the power of genetics: fast forward genetics in Caenorhabditis elegans. Mol Genet Genomics 2020; 296:1-20. [PMID: 32888055 DOI: 10.1007/s00438-020-01721-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2020] [Accepted: 08/27/2020] [Indexed: 12/23/2022]
Abstract
Forward genetics is a powerful tool to unravel molecular mechanisms of diverse biological processes. The success of genetic screens primarily relies on the ease of genetic manipulation of an organism and the availability of a plethora of genetic tools. The roundworm Caenorhabditis elegans has been one of the favorite models for genetic studies due to its hermaphroditic lifestyle, ease of maintenance, and availability of various genetic manipulation tools. The strength of C. elegans genetics is highlighted by the leading role of this organism in the discovery of several conserved biological processes. In this review, the principles and strategies for forward genetics in C. elegans are discussed. Further, the recent advancements that have drastically accelerated the otherwise time-consuming process of mutation identification, making forward genetic screens a method of choice for understanding biological functions, are discussed. The emphasis of the review has been on providing practical and conceptual pointers for designing genetic screens that will identify mutations, specifically disrupting the biological processes of interest.
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17
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Sweat gland regeneration: Current strategies and future opportunities. Biomaterials 2020; 255:120201. [PMID: 32592872 DOI: 10.1016/j.biomaterials.2020.120201] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Revised: 04/21/2020] [Accepted: 06/09/2020] [Indexed: 12/13/2022]
Abstract
For patients with extensive skin defects, loss of sweat glands (SwGs) greatly decreases their quality of life. Indeed, difficulties in thermoregulation, ion reabsorption, and maintaining fluid balance might render them susceptible to hyperthermia, heatstroke, or even death. Despite extensive studies on the stem cell biology of the skin in recent years, in-situ regeneration of SwGs with both structural and functional fidelity is still challenging because of the limited regenerative capacity and cell fate control of resident progenitors. To overcome these challenges, one must consider both the intrinsic factors relevant to genetic and epigenetic regulation and cues from the cellular microenvironment. Here, we describe recent progress in molecular biology, developmental pathways, and cellular evolution associated with SwGdevelopment and maturation. This is followed by a summary of the current strategies used for cell-fate modulation, transmembrane drug delivery, and scaffold design associated with SwGregeneration. Finally, we offer perspectives for creating more sophisticated systems to accelerate patients' innate healing capacity and developing engineered skin constructs to treat or replace damaged tissues structurally and functionally.
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18
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Ofenbauer A, Tursun B. Strategies for in vivo reprogramming. Curr Opin Cell Biol 2019; 61:9-15. [DOI: 10.1016/j.ceb.2019.06.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 05/29/2019] [Accepted: 06/14/2019] [Indexed: 02/08/2023]
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19
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Rothman J, Jarriault S. Developmental Plasticity and Cellular Reprogramming in Caenorhabditis elegans. Genetics 2019; 213:723-757. [PMID: 31685551 PMCID: PMC6827377 DOI: 10.1534/genetics.119.302333] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Accepted: 07/25/2019] [Indexed: 12/28/2022] Open
Abstract
While Caenorhabditis elegans was originally regarded as a model for investigating determinate developmental programs, landmark studies have subsequently shown that the largely invariant pattern of development in the animal does not reflect irreversibility in rigidly fixed cell fates. Rather, cells at all stages of development, in both the soma and germline, have been shown to be capable of changing their fates through mutation or forced expression of fate-determining factors, as well as during the normal course of development. In this chapter, we review the basis for natural and induced cellular plasticity in C. elegans We describe the events that progressively restrict cellular differentiation during embryogenesis, starting with the multipotency-to-commitment transition (MCT) and subsequently through postembryonic development of the animal, and consider the range of molecular processes, including transcriptional and translational control systems, that contribute to cellular plasticity. These findings in the worm are discussed in the context of both classical and recent studies of cellular plasticity in vertebrate systems.
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Affiliation(s)
- Joel Rothman
- Department of MCD Biology and Neuroscience Research Institute, University of California, Santa Barbara, California 93111, and
| | - Sophie Jarriault
- IGBMC (Institut de Génétique et de Biologie Moléculaire et Cellulaire), Department of Development and Stem Cells, CNRS UMR7104, Inserm U1258, Université de Strasbourg, 67404 Illkirch CU Strasbourg, France
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20
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Abstract
Single cell biology is currently revolutionizing developmental and evolutionary biology, revealing new cell types and states in an impressive range of biological systems. With the accumulation of data, however, the field is grappling with a central unanswered question: what exactly is a cell type? This question is further complicated by the inherently dynamic nature of developmental processes. In this Hypothesis article, we propose that a 'periodic table of cell types' can be used as a framework for distinguishing cell types from cell states, in which the periods and groups correspond to developmental trajectories and stages along differentiation, respectively. The different states of the same cell type are further analogous to 'isotopes'. We also highlight how the concept of a periodic table of cell types could be useful for predicting new cell types and states, and for recognizing relationships between cell types throughout development and evolution.
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Affiliation(s)
- Bo Xia
- Institute for Computational Medicine, NYU Langone Health, New York, NY 10016, USA
| | - Itai Yanai
- Institute for Computational Medicine, NYU Langone Health, New York, NY 10016, USA
- Department of Biochemistry and Molecular Pharmacology, NYU Langone Health, New York, NY 10016, USA
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21
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Coraggio F, Püschel R, Marti A, Meister P. Polycomb and Notch signaling regulate cell proliferation potential during Caenorhabditis elegans life cycle. Life Sci Alliance 2019; 2:e201800170. [PMID: 30599047 PMCID: PMC6306570 DOI: 10.26508/lsa.201800170] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Revised: 12/17/2018] [Accepted: 12/18/2018] [Indexed: 12/27/2022] Open
Abstract
Stable cell fate is an essential feature for multicellular organisms in which individual cells achieve specialized functions. Caenorhabditis elegans is a great model to analyze the determinants of cell fate stability because of its invariant lineage. We present a tractable cell fate challenge system that uses the induction of fate-specifying transcription factors. We show that wild-type differentiated animals are highly resistant to fate challenge. Removal of heterochromatin marks showed marked differences: the absence of histone 3 lysine 9 methylation (H3K9) has no effect on fate stability, whereas Polycomb homolog mes-2 mutants lacking H3K27 methylation terminally arrest larval development upon fate challenge. Unexpectedly, the arrest correlated with widespread cell proliferation rather than transdifferentiation. Using a candidate RNAi larval arrest-rescue screen, we show that the LIN-12Notch pathway is essential for hyperplasia induction. Moreover, Notch signaling appears downstream of food-sensing pathways, as dauers and first larval stage diapause animals are resistant to fate challenge. Our results demonstrate an equilibrium between proliferation and differentiation regulated by Polycomb and Notch signaling in the soma during the nematode life cycle.
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Affiliation(s)
- Francesca Coraggio
- Cell Fate and Nuclear Organization, Institute of Cell Biology, University of Bern, Bern, Switzerland
- Graduate School for Cellular and Biomedical Sciences, University of Bern, Bern, Switzerland
| | - Ringo Püschel
- Cell Fate and Nuclear Organization, Institute of Cell Biology, University of Bern, Bern, Switzerland
- Graduate School for Cellular and Biomedical Sciences, University of Bern, Bern, Switzerland
| | - Alisha Marti
- Cell Fate and Nuclear Organization, Institute of Cell Biology, University of Bern, Bern, Switzerland
| | - Peter Meister
- Cell Fate and Nuclear Organization, Institute of Cell Biology, University of Bern, Bern, Switzerland
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22
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Reid A, Tursun B. Transdifferentiation: do transition states lie on the path of development? CURRENT OPINION IN SYSTEMS BIOLOGY 2018; 11:18-23. [PMID: 30386832 PMCID: PMC6202785 DOI: 10.1016/j.coisb.2018.07.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The direct conversion of one differentiated cell fate into another identity is a process known as Transdifferentiation. During Transdifferentiation, cells pass through intermediate states that are not well understood. Given the potential application of transdifferentiation in regenerative medicine and disease modeling, a better understanding of intermediate states is crucial to avoid uncontrolled conversion or proliferation, which pose a risk for patients. Researchers have begun to analyze the transcriptomes of donor, converting and target cells of Transdifferentiation with single cell resolution to compare transitional states to those found along the path of development. Here, we review examples of Transdifferentiation in a range of model systems and organisms. We propose that cells pass either through a mixed, unspecific intermediate or progenitor-like state during Transdifferentiation, which, to varying degrees, resemble states seen during development.
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Affiliation(s)
- Anna Reid
- Berlin Institute for Medical Systems Biology, 13125 Berlin, Germany
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association, 13125 Berlin, Germany
| | - Baris Tursun
- Berlin Institute for Medical Systems Biology, 13125 Berlin, Germany
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association, 13125 Berlin, Germany
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23
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Ahringer J, Gasser SM. Repressive Chromatin in Caenorhabditis elegans: Establishment, Composition, and Function. Genetics 2018; 208:491-511. [PMID: 29378810 PMCID: PMC5788517 DOI: 10.1534/genetics.117.300386] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Accepted: 11/18/2017] [Indexed: 01/08/2023] Open
Abstract
Chromatin is organized and compacted in the nucleus through the association of histones and other proteins, which together control genomic activity. Two broad types of chromatin can be distinguished: euchromatin, which is generally transcriptionally active, and heterochromatin, which is repressed. Here we examine the current state of our understanding of repressed chromatin in Caenorhabditis elegans, focusing on roles of histone modifications associated with repression, such as methylation of histone H3 lysine 9 (H3K9me2/3) or the Polycomb Repressive Complex 2 (MES-2/3/6)-deposited modification H3K27me3, and on proteins that recognize these modifications. Proteins involved in chromatin repression are important for development, and have demonstrated roles in nuclear organization, repetitive element silencing, genome integrity, and the regulation of euchromatin. Additionally, chromatin factors participate in repression with small RNA pathways. Recent findings shed light on heterochromatin function and regulation in C. elegans, and should inform our understanding of repressed chromatin in other animals.
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Affiliation(s)
- Julie Ahringer
- The Gurdon Institute, University of Cambridge CB2 1QN, United Kingdom
- Department of Genetics, University of Cambridge CB2 1QN, United Kingdom
| | - Susan M Gasser
- Friedrich Miescher Institute for Biomedical Research (FMI), 4058 Basel, Switzerland, and
- Faculty of Natural Sciences, University of Basel, 4056, Switzerland
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24
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Spickard EA, Joshi PM, Rothman JH. The multipotency-to-commitment transition in Caenorhabditis elegans-implications for reprogramming from cells to organs. FEBS Lett 2018; 592:838-851. [PMID: 29334121 DOI: 10.1002/1873-3468.12977] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Revised: 12/22/2017] [Accepted: 01/11/2018] [Indexed: 12/13/2022]
Abstract
In animal embryos, cells transition from a multipotential state, with the capacity to adopt multiple fates, into an irreversible, committed state of differentiation. This multipotency-to-commitment transition (MCT) is evident from experiments in which cell fate is reprogrammed by transcription factors for cell type-specific differentiation, as has been observed extensively in Caenorhabditis elegans. Although factors that direct differentiation into each of the three germ layer types cannot generally reprogram cells after the MCT in this animal, transcription factors for endoderm development are able to do so in multiple differentiated cell types. In one case, these factors can redirect the development of an entire organ in the process of "transorganogenesis". Natural transdifferentiation also occurs in a small number of differentiated cells during normal C. elegans development. We review these reprogramming and transdifferentiation events, highlighting the cellular and developmental contexts in which they occur, and discuss common themes underlying direct cell lineage reprogramming. Although certain aspects may be unique to the model system, growing evidence suggests that some mechanisms are evolutionarily conserved and may shed light on cellular plasticity and disease in humans.
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Affiliation(s)
- Erik A Spickard
- Department of MCD Biology and Neuroscience Research Institute, University of California Santa Barbara, CA, USA
| | - Pradeep M Joshi
- Department of MCD Biology and Neuroscience Research Institute, University of California Santa Barbara, CA, USA
| | - Joel H Rothman
- Department of MCD Biology and Neuroscience Research Institute, University of California Santa Barbara, CA, USA
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25
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Vibert L, Daulny A, Jarriault S. Wound healing, cellular regeneration and plasticity: the elegans way. THE INTERNATIONAL JOURNAL OF DEVELOPMENTAL BIOLOGY 2018; 62:491-505. [PMID: 29938761 PMCID: PMC6161810 DOI: 10.1387/ijdb.180123sj] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Regeneration and wound healing are complex processes that allow organs and tissues to regain their integrity and functionality after injury. Wound healing, a key property of epithelia, involves tissue closure that in some cases leads to scar formation. Regeneration, a process rather limited in mammals, is the capacity to regrow (parts of) an organ or a tissue, after damage or amputation. What are the properties of organs and the features of tissue permitting functional regrowth and repair? What are the cellular and molecular mechanisms underlying these processes? These questions are crucial both in fundamental and applied contexts, with important medical implications. The mechanisms and cells underlying tissue repair have thus been the focus of intense investigation. The last decades have seen rapid progress in the domain and new models emerging. Here, we review the fundamental advances and the perspectives that the use of C. elegans as a model have brought to the mechanisms of wound healing and cellular plasticity, axon regeneration and transdifferentiation in vivo.
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Affiliation(s)
- Laura Vibert
- Department of Development and Stem Cells, IGBMC (Institut de Génétique et de Biologie Moléculaire et Cellulaire), CNRS UMR 7104/INSERM U1258, Université de Strasbourg, Strasbourg, France
| | - Anne Daulny
- Department of Development and Stem Cells, IGBMC (Institut de Génétique et de Biologie Moléculaire et Cellulaire), CNRS UMR 7104/INSERM U1258, Université de Strasbourg, Strasbourg, France
| | - Sophie Jarriault
- Department of Development and Stem Cells, IGBMC (Institut de Génétique et de Biologie Moléculaire et Cellulaire), CNRS UMR 7104/INSERM U1258, Université de Strasbourg, Strasbourg, France
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26
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Abstract
Over 100 years of sponge biology research has demonstrated spectacular diversity of cell behaviors during embryonic development, metamorphosis and regeneration. The past two decades have allowed the first glimpses into molecular and cellular mechanisms of these processes. We have learned that while embryonic development of sponges utilizes a conserved set of developmental regulatory genes known from other animals, sponge cell differentiation appears unusually labile. During normal development, and especially as a response to injury, sponge cells appear to have an uncanny ability to transdifferentiate. Here, I argue that sponge cell differentiation plasticity does not preclude homology of cell types and processes between sponges and other animals. Instead, it does provide a wonderful opportunity to better understand transdifferentiation processes in all animals.
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Affiliation(s)
- Maja Adamska
- Division of Biomedical Science and Biochemistry, Research School of Biology, The Australian National University, Canberra, Australia.
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27
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Jin Y, Qi YB. Building stereotypic connectivity: mechanistic insights into structural plasticity from C. elegans. Curr Opin Neurobiol 2017; 48:97-105. [PMID: 29182952 DOI: 10.1016/j.conb.2017.11.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Revised: 11/07/2017] [Accepted: 11/14/2017] [Indexed: 01/10/2023]
Abstract
The ability of neurons to modify or remodel their synaptic connectivity is critical for the function of neural circuitry throughout the life of an animal. Understanding the mechanisms underlying neuronal structural changes is central to our knowledge of how the nervous system is shaped for complex behaviors and how it further adapts to developmental and environmental demands. Caenorhabditis elegans provides a powerful model for examining developmental processes and for discovering mechanisms controlling neural plasticity. Recent findings have identified conserved themes underlying neural plasticity in development and under environmental stress.
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Affiliation(s)
- Yishi Jin
- Section of Neurobiology, Division of Biological Sciences, University of California, San Diego, La Jolla, CA 92093, USA.
| | - Yingchuan B Qi
- Zhejiang Key Laboratory of Organ Development and Regeneration, College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 310036, China.
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28
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Abstract
Somatic cells can be reprogrammed to pluripotent stem cells or transdifferentiate to another lineage cell type. Much efforts have been made to unravel the epigenetic mechanisms underlying the cell fate conversion. Histone modifications as the major epigenetic regulator are implicated in various aspects of reprogramming and transdifferentiation. Here, we discuss the roles of histone modifications on reprogramming and transdifferentiation and hopefully provide new insights into induction and promotion of the cell fate conversion by modulating histone modifications.
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29
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Smith DK, He M, Zhang CL, Zheng JC. The therapeutic potential of cell identity reprogramming for the treatment of aging-related neurodegenerative disorders. Prog Neurobiol 2017; 157:212-229. [PMID: 26844759 PMCID: PMC5848468 DOI: 10.1016/j.pneurobio.2016.01.006] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Revised: 11/25/2015] [Accepted: 01/04/2016] [Indexed: 12/12/2022]
Abstract
Neural cell identity reprogramming strategies aim to treat age-related neurodegenerative disorders with newly induced neurons that regenerate neural architecture and functional circuits in vivo. The isolation and neural differentiation of pluripotent embryonic stem cells provided the first in vitro models of human neurodegenerative disease. Investigation into the molecular mechanisms underlying stem cell pluripotency revealed that somatic cells could be reprogrammed to induced pluripotent stem cells (iPSCs) and these cells could be used to model Alzheimer disease, amyotrophic lateral sclerosis, Huntington disease, and Parkinson disease. Additional neural precursor and direct transdifferentiation strategies further enabled the induction of diverse neural linages and neuron subtypes both in vitro and in vivo. In this review, we highlight neural induction strategies that utilize stem cells, iPSCs, and lineage reprogramming to model or treat age-related neurodegenerative diseases, as well as, the clinical challenges related to neural transplantation and in vivo reprogramming strategies.
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Affiliation(s)
- Derek K Smith
- Department of Molecular Biology, The University of Texas Southwestern Medical Center, 6000 Harry Hines Boulevard, Dallas, TX 75390, USA; Hamon Center for Regenerative Science and Medicine, The University of Texas Southwestern Medical Center, 6000 Harry Hines Boulevard, Dallas, TX 75390, USA
| | - Miao He
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, NE 68198, USA; Department of Physical Therapy, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Chun-Li Zhang
- Department of Molecular Biology, The University of Texas Southwestern Medical Center, 6000 Harry Hines Boulevard, Dallas, TX 75390, USA; Hamon Center for Regenerative Science and Medicine, The University of Texas Southwestern Medical Center, 6000 Harry Hines Boulevard, Dallas, TX 75390, USA.
| | - Jialin C Zheng
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, NE 68198, USA; Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE 68198, USA; Department of Family Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA; Center for Translational Neurodegeneration and Regenerative Therapy, the Collaborative Innovation Center for Brain Science, Shanghai Tenth People's Hospital affiliated to Tongji University School of Medicine, Shanghai 200072, China.
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30
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Galliot B, Crescenzi M, Jacinto A, Tajbakhsh S. Trends in tissue repair and regeneration. Development 2017; 144:357-364. [PMID: 28143842 DOI: 10.1242/dev.144279] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The 6th EMBO conference on the Molecular and Cellular Basis of Regeneration and Tissue Repair took place in Paestum (Italy) on the 17th-21st September, 2016. The 160 scientists who attended discussed the importance of cellular and tissue plasticity, biophysical aspects of regeneration, the diverse roles of injury-induced immune responses, strategies to reactivate regeneration in mammals, links between regeneration and ageing, and the impact of non-mammalian models on regenerative medicine.
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Affiliation(s)
- Brigitte Galliot
- Department of Genetics and Evolution, Institute of Genetics and Genomics in Geneva (iGE3), University of Geneva, CH-1211 Geneva 04, Switzerland
| | - Marco Crescenzi
- Department of Cell Biology and Neurosciences, National Institute of Health, I-00161 Roma, Italy
| | - Antonio Jacinto
- CEDOC, NOVA Medical School, NOVA University of Lisbon, Lisboa 1169-056, Portugal
| | - Shahragim Tajbakhsh
- Department of Developmental & Stem Cell Biology, Stem Cells & Development Unit, CNRS UMR 3738, Institut Pasteur, 75015 Paris, France
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31
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Luo S, Horvitz HR. The CDK8 Complex and Proneural Proteins Together Drive Neurogenesis from a Mesodermal Lineage. Curr Biol 2017; 27:661-672. [PMID: 28238659 DOI: 10.1016/j.cub.2017.01.056] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Revised: 12/08/2016] [Accepted: 01/26/2017] [Indexed: 11/25/2022]
Abstract
At least some animal species can generate neurons from mesoderm or endoderm, but the underlying mechanisms remain unknown. We screened for C. elegans mutants in which the presumptive mesoderm-derived I4 neuron adopts a muscle-like cell fate. From this screen, we identified HLH-3, the C. elegans homolog of a mammalian proneural protein (Ascl1) used for in vitro neuronal reprogramming, as required for efficient I4 neurogenesis. We discovered that the CDK-8 Mediator kinase module acts together with a second proneural protein, HLH-2, and in parallel to HLH-3 to promote I4 neurogenesis. Genetic analysis revealed that CDK-8 most likely promotes I4 neurogenesis by inhibiting the CDK-7/CYH-1 (CDK7/cyclin H) kinase module of the transcription initiation factor TFIIH. Ectopic expression of HLH-2 and HLH-3 together promoted expression of neuronal features in non-neuronal cells. These findings reveal that the Mediator CDK8 kinase module can promote non-ectodermal neurogenesis and suggest that inhibiting CDK7/cyclin H might similarly promote neurogenesis.
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Affiliation(s)
- Shuo Luo
- Howard Hughes Medical Institute and Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - H Robert Horvitz
- Howard Hughes Medical Institute and Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
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An N, Xu H, Gao WQ, Yang H. Direct Conversion of Somatic Cells into Induced Neurons. Mol Neurobiol 2016; 55:642-651. [PMID: 27981499 DOI: 10.1007/s12035-016-0350-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2016] [Accepted: 12/07/2016] [Indexed: 01/29/2023]
Abstract
The progressive loss and degeneration of neurons in the central nervous system (CNS), as a result of traumas or diseases including Alzheimer's, Parkinson's, Huntington's disease, stroke, and traumatic injury to the brain and spinal cord, can usually have devastating effects on quality of life. The current strategies available for treatments are described including drug delivery, surgery, electrical stimulation, and cell-based tissue engineering approaches. However, apart from cell-based therapy, other attempts are limited in improving clinical outcomes. Recently, stem cell and neural stem cell (NSC) in particular therapy has been proposed as an attractive and promising strategy for regenerative medicine due to their unique biological attributes, such as giving rise to neuronal lineage commitment in accordance with the neural development. Nevertheless, stem cell strategy still faces numerous challenges, including ethical issue, tumor formation, and graft rejection. Thus, seeking a more appropriate approach like direct reprogramming or lineage reprogramming is critical. Compared to induced pluripotent stem cells (iPSCs) and embryonic stem cells (ESCs), direct lineage reprogramming of somatic cells to generate induced neurons (iNs) without undergoing a state of pluripotent still has several advantages such as short induction cycle, high transdifferentiation efficiency, no ethical concerns, and risk of neoplasia. On the basis of these advantages, cell reprogramming will hold great promise for therapeutic cell replacement, disease modeling establishment, drug screening, and personalized medicine. Here, we systematically review recent advances in somatic lineage reprogramming into iNs, including the identification of novel reprogramming factors, the underlying molecular mechanisms and the concerns exist, as well as the major challenges in the future.
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Affiliation(s)
- Na An
- State Key Laboratory of Oncogenes and Related Genes, Renji-Med X Clinical Stem Cell Research Center, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, 200127, China
| | - Huiming Xu
- State Key Laboratory of Oncogenes and Related Genes, Renji-Med X Clinical Stem Cell Research Center, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, 200127, China
| | - Wei-Qiang Gao
- State Key Laboratory of Oncogenes and Related Genes, Renji-Med X Clinical Stem Cell Research Center, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, 200127, China.
| | - Hao Yang
- State Key Laboratory of Oncogenes and Related Genes, Renji-Med X Clinical Stem Cell Research Center, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, 200127, China.
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33
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Evolutionary origin of endochondral ossification: the transdifferentiation hypothesis. Dev Genes Evol 2016; 227:121-127. [DOI: 10.1007/s00427-016-0567-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Accepted: 11/23/2016] [Indexed: 02/06/2023]
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34
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Doitsidou M, Jarriault S, Poole RJ. Next-Generation Sequencing-Based Approaches for Mutation Mapping and Identification in Caenorhabditis elegans. Genetics 2016; 204:451-474. [PMID: 27729495 PMCID: PMC5068839 DOI: 10.1534/genetics.115.186197] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Accepted: 08/05/2016] [Indexed: 02/07/2023] Open
Abstract
The use of next-generation sequencing (NGS) has revolutionized the way phenotypic traits are assigned to genes. In this review, we describe NGS-based methods for mapping a mutation and identifying its molecular identity, with an emphasis on applications in Caenorhabditis elegans In addition to an overview of the general principles and concepts, we discuss the main methods, provide practical and conceptual pointers, and guide the reader in the types of bioinformatics analyses that are required. Owing to the speed and the plummeting costs of NGS-based methods, mapping and cloning a mutation of interest has become straightforward, quick, and relatively easy. Removing this bottleneck previously associated with forward genetic screens has significantly advanced the use of genetics to probe fundamental biological processes in an unbiased manner.
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Affiliation(s)
- Maria Doitsidou
- Centre for Integrative Physiology, University of Edinburgh, EH8 9XD, Scotland
| | - Sophie Jarriault
- L'Institut de Génétique et de Biologie Moléculaire et Cellulaire, Centre National de la Recherche Scientifique UMR 7104/Institut National de la Santé et de la Recherche Médicale U964, Université de Strasbourg, 67404, France
| | - Richard J Poole
- Department of Cell and Developmental Biology, University College London, WC1E 6BT, United Kingdom
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35
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Becker SF, Jarriault S. Natural and induced direct reprogramming: mechanisms, concepts and general principles-from the worm to vertebrates. Curr Opin Genet Dev 2016; 40:154-163. [PMID: 27690213 DOI: 10.1016/j.gde.2016.06.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2016] [Revised: 05/31/2016] [Accepted: 06/23/2016] [Indexed: 12/19/2022]
Abstract
Elucidating the mechanisms underlying cell fate determination, cell identity maintenance and cell reprogramming in vivo is one of the main challenges in today's science. Such knowledge of fundamental importance will further provide new leads for early diagnostics and targeted therapy approaches both in regenerative medicine and cancer research. This review focuses on recent mechanistic findings and factors that influence the differentiated state of cells in direct reprogramming events, aka transdifferentiation. In particular, we will look at the mechanistic and conceptual advances brought by the use of the nematode Caenorhabditis elegans and highlight common themes across phyla.
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Affiliation(s)
- Sarah F Becker
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), CNRS UMR7104, INSERM U964, Université de Strasbourg, 1 rue Laurent Fries, 67404 Illkirch Cu Strasbourg, France
| | - Sophie Jarriault
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), CNRS UMR7104, INSERM U964, Université de Strasbourg, 1 rue Laurent Fries, 67404 Illkirch Cu Strasbourg, France.
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36
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Seelk S, Adrian-Kalchhauser I, Hargitai B, Hajduskova M, Gutnik S, Tursun B, Ciosk R. Increasing Notch signaling antagonizes PRC2-mediated silencing to promote reprograming of germ cells into neurons. eLife 2016; 5. [PMID: 27602485 PMCID: PMC5045294 DOI: 10.7554/elife.15477] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Accepted: 09/06/2016] [Indexed: 12/12/2022] Open
Abstract
Cell-fate reprograming is at the heart of development, yet very little is known about the molecular mechanisms promoting or inhibiting reprograming in intact organisms. In the C. elegans germline, reprograming germ cells into somatic cells requires chromatin perturbation. Here, we describe that such reprograming is facilitated by GLP-1/Notch signaling pathway. This is surprising, since this pathway is best known for maintaining undifferentiated germline stem cells/progenitors. Through a combination of genetics, tissue-specific transcriptome analysis, and functional studies of candidate genes, we uncovered a possible explanation for this unexpected role of GLP-1/Notch. We propose that GLP-1/Notch promotes reprograming by activating specific genes, silenced by the Polycomb repressive complex 2 (PRC2), and identify the conserved histone demethylase UTX-1 as a crucial GLP-1/Notch target facilitating reprograming. These findings have wide implications, ranging from development to diseases associated with abnormal Notch signaling. DOI:http://dx.doi.org/10.7554/eLife.15477.001 The DNA in genes encodes the basic information needed to build an organism or control its day-to-day operations. Most cells in an organism contain the same genetic information, but different types of cell use the information differently. For example, many of the genes that are active in a muscle cell are different from those that are active in a skin cell. These different patterns of gene activation largely determine a cell’s identity and are brought about by DNA-binding proteins or chemical modifications to the DNA (which are both forms of so-called epigenetic regulation). Nevertheless, cells occasionally change their identities – a phenomenon that is referred to as reprograming. This process allows tissues to be regenerated after wounding, but, due to technical difficulties, reprograming has been often studied in isolated cells grown in a dish. Seelk, Adrian-Kalchhauser et al. set out to understand how being surrounded by intact tissue influences reprograming. The experiments made use of C. elegans worms, because disturbing how this worm’s DNA is packaged can trigger its cells to undergo reprograming. Seelk, Adrian-Kalchhauser et al. show that a signaling pathway that is found in many different animals enhances this kind of reprograming in C. elegans. On the one hand, these findings help in understanding how epigenetic regulation can be altered by a specific tissue environment. On the other hand, the findings also suggest that abnormal signaling can result in altered epigenetic control of gene expression and lead to cells changing their identity. Indeed, increased signaling is linked to a major epigenetic mechanism seen in specific blood tumors, suggesting that the regulatory principles uncovered using this simple worm model could eventually provide insights into a human disease. A future challenge will be to determine precisely how the studied signaling pathway interacts with the epigenetic regulator that controls reprograming. Understanding this interaction in molecular detail could help to devise strategies for controlling reprograming. These strategies could in turn lead to treatments for people with conditions that cause specific cells types to be lost, such as Alzheimer’s disease or injuries. DOI:http://dx.doi.org/10.7554/eLife.15477.002
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Affiliation(s)
- Stefanie Seelk
- Berlin Institute for Medical Systems Biology, Max-Delbrück-Center for Molecular Medicine, Berlin, Germany
| | | | - Balázs Hargitai
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Martina Hajduskova
- Berlin Institute for Medical Systems Biology, Max-Delbrück-Center for Molecular Medicine, Berlin, Germany
| | - Silvia Gutnik
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Baris Tursun
- Berlin Institute for Medical Systems Biology, Max-Delbrück-Center for Molecular Medicine, Berlin, Germany
| | - Rafal Ciosk
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
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37
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Masserdotti G, Gascón S, Götz M. Direct neuronal reprogramming: learning from and for development. Development 2016; 143:2494-510. [DOI: 10.1242/dev.092163] [Citation(s) in RCA: 101] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The key signalling pathways and transcriptional programmes that instruct neuronal diversity during development have largely been identified. In this Review, we discuss how this knowledge has been used to successfully reprogramme various cell types into an amazing array of distinct types of functional neurons. We further discuss the extent to which direct neuronal reprogramming recapitulates embryonic development, and examine the particular barriers to reprogramming that may exist given a cell's unique developmental history. We conclude with a recently proposed model for cell specification called the ‘Cook Islands’ model, and consider whether it is a fitting model for cell specification based on recent results from the direct reprogramming field.
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Affiliation(s)
- Giacomo Masserdotti
- Institute of Stem Cell Research, Helmholtz Center Munich, Ingolstädter Landstrasse 1, Neuherberg/Munich D-85764, Germany
- Physiological Genomics, Biomedical Center, Ludwig-Maximilians University Munich, Großhadernerstrasse 9, Martinsried 82154, Germany
| | - Sergio Gascón
- Institute of Stem Cell Research, Helmholtz Center Munich, Ingolstädter Landstrasse 1, Neuherberg/Munich D-85764, Germany
- Physiological Genomics, Biomedical Center, Ludwig-Maximilians University Munich, Großhadernerstrasse 9, Martinsried 82154, Germany
| | - Magdalena Götz
- Institute of Stem Cell Research, Helmholtz Center Munich, Ingolstädter Landstrasse 1, Neuherberg/Munich D-85764, Germany
- Physiological Genomics, Biomedical Center, Ludwig-Maximilians University Munich, Großhadernerstrasse 9, Martinsried 82154, Germany
- Excellence Cluster of Systems Neurology, Großhadernerstrasse 9, Martinsried 82154, Germany
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38
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Piechowski J. Trophoblastic-like transdifferentiation: A key to oncogenesis. Crit Rev Oncol Hematol 2016; 101:1-11. [DOI: 10.1016/j.critrevonc.2016.01.019] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Revised: 11/29/2015] [Accepted: 01/19/2016] [Indexed: 12/18/2022] Open
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39
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Adult cell plasticity in vivo: de-differentiation and transdifferentiation are back in style. Nat Rev Mol Cell Biol 2016; 17:413-25. [PMID: 26979497 DOI: 10.1038/nrm.2016.24] [Citation(s) in RCA: 289] [Impact Index Per Article: 36.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Biologists have long been intrigued by the possibility that cells can change their identity, a phenomenon known as cellular plasticity. The discovery that terminally differentiated cells can be experimentally coaxed to become pluripotent has invigorated the field, and recent studies have demonstrated that changes in cell identity are not limited to the laboratory. Specifically, certain adult cells retain the capacity to de-differentiate or transdifferentiate under physiological conditions, as part of an organ's normal injury response. Recent studies have highlighted the extent to which cell plasticity contributes to tissue homeostasis, findings that have implications for cell-based therapy.
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40
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Gracida X, Norris AD, Calarco JA. Regulation of Tissue-Specific Alternative Splicing: C. elegans as a Model System. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 907:229-61. [DOI: 10.1007/978-3-319-29073-7_10] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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41
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Physical Interactions and Functional Coordination between the Core Subunits of Set1/Mll Complexes and the Reprogramming Factors. PLoS One 2015; 10:e0145336. [PMID: 26691508 PMCID: PMC4686221 DOI: 10.1371/journal.pone.0145336] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2015] [Accepted: 12/02/2015] [Indexed: 11/19/2022] Open
Abstract
Differentiated cells can be reprogrammed to the pluripotent state by overexpression of defined factors, and this process is profoundly influenced by epigenetic mechanisms including dynamic histone modifications. Changes in H3K4 methylation have been shown to be the predominant activating response in the early stage of cellular reprogramming. Mechanisms underlying such epigenetic priming, however, are not well understood. Here we show that the expression of the reprogramming factors (Yamanaka factors, Oct4, Sox2, Klf4 and Myc), especially Myc, directly promotes the expression of certain core subunits of the Set1/Mll family of H3K4 methyltransferase complexes. A dynamic recruitment of the Set1/Mll complexes largely, though not sufficiently in its own, explains the dynamics of the H3K4 methylation during cellular reprogramming. We then demonstrate that the core subunits of the Set1/Mll complexes physically interact with mainly Sox2 and Myc among the Yamanaka factors. We further show that Sox2 directly binds the Ash2l subunit in the Set1/Mll complexes and this binding is mediated by the HMG domain of Sox2. Functionally, we show that the Set1/Mll complex core subunits are required for efficient cellular reprogramming. We also show that Dpy30, one of the core subunits in the complexes, is required for the efficient target binding of the reprogramming factors. Interestingly, such requirement is not necessarily dependent on locus-specific H3K4 methylation. Our work provides a better understanding of how the reprogramming factors physically interact and functionally coordinate with a key group of epigenetic modulators to mediate transitions of the chromatin state involved in cellular reprogramming.
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42
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Abstract
The direct lineage reprogramming of one specialized cell type into another using defined factors has fundamentally re-shaped traditional concepts regarding the epigenetic stability of differentiated cells. With the rapid increase in cell types generated through direct conversion in recent years, this strategy has become a promising approach for producing functional cells. Here, we review recent advances in lineage reprogramming, including the identification of novel reprogramming factors, underlying molecular mechanisms, strategies for generating functionally mature cells, and assays for characterizing induced cells. We also discuss progress toward the application of lineage reprogramming and the major future challenges for this strategy.
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43
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Dimitrova E, Turberfield AH, Klose RJ. Histone demethylases in chromatin biology and beyond. EMBO Rep 2015; 16:1620-39. [PMID: 26564907 PMCID: PMC4687429 DOI: 10.15252/embr.201541113] [Citation(s) in RCA: 137] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Accepted: 10/06/2015] [Indexed: 01/05/2023] Open
Abstract
Histone methylation plays fundamental roles in regulating chromatin‐based processes. With the discovery of histone demethylases over a decade ago, it is now clear that histone methylation is dynamically regulated to shape the epigenome and regulate important nuclear processes including transcription, cell cycle control and DNA repair. In addition, recent observations suggest that these enzymes could also have functions beyond their originally proposed role as histone demethylases. In this review, we focus on recent advances in our understanding of the molecular mechanisms that underpin the role of histone demethylases in a wide variety of normal cellular processes.
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Affiliation(s)
| | | | - Robert J Klose
- Department of Biochemistry, University of Oxford, Oxford, UK
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44
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Sammut M, Cook SJ, Nguyen KCQ, Felton T, Hall DH, Emmons SW, Poole RJ, Barrios A. Glia-derived neurons are required for sex-specific learning in C. elegans. Nature 2015; 526:385-390. [PMID: 26469050 PMCID: PMC4650210 DOI: 10.1038/nature15700] [Citation(s) in RCA: 81] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2015] [Accepted: 09/10/2015] [Indexed: 12/14/2022]
Abstract
Sex differences in behaviour extend to cognitive-like processes such as learning, but the underlying dimorphisms in neural circuit development and organization that generate these behavioural differences are largely unknown. Here we define at the single-cell level-from development, through neural circuit connectivity, to function-the neural basis of a sex-specific learning in the nematode Caenorhabditis elegans. We show that sexual conditioning, a form of associative learning, requires a pair of male-specific interneurons whose progenitors are fully differentiated glia. These neurons are generated during sexual maturation and incorporated into pre-exisiting sex-shared circuits to couple chemotactic responses to reproductive priorities. Our findings reveal a general role for glia as neural progenitors across metazoan taxa and demonstrate that the addition of sex-specific neuron types to brain circuits during sexual maturation is an important mechanism for the generation of sexually dimorphic plasticity in learning.
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Affiliation(s)
- Michele Sammut
- Department of Cell and Developmental Biology, University College London, London, WC1E 6BT
| | - Steven J Cook
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461
| | - Ken C Q Nguyen
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461
| | - Terry Felton
- Department of Cell and Developmental Biology, University College London, London, WC1E 6BT
| | - David H Hall
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461
| | - Scott W Emmons
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461
- Department of Genetics, Albert Einstein College of Medicine, Bronx, NY 10461
| | - Richard J Poole
- Department of Cell and Developmental Biology, University College London, London, WC1E 6BT
| | - Arantza Barrios
- Department of Cell and Developmental Biology, University College London, London, WC1E 6BT
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45
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Labbadia J, Morimoto RI. Repression of the Heat Shock Response Is a Programmed Event at the Onset of Reproduction. Mol Cell 2015. [PMID: 26212459 DOI: 10.1016/j.molcel.2015.06.027] [Citation(s) in RCA: 227] [Impact Index Per Article: 25.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The heat shock response (HSR) is essential for proteostasis and cellular health. In metazoans, aging is associated with a decline in quality control, thus increasing the risk for protein conformational disease. Here, we show that in C. elegans, the HSR declines precipitously over a 4 hr period in early adulthood coincident with the onset of reproductive maturity. Repression of the HSR occurs due to an increase in H3K27me3 marks at stress gene loci, the timing of which is determined by reduced expression of the H3K27 demethylase jmjd-3.1. This results in a repressed chromatin state that interferes with HSF-1 binding and suppresses transcription initiation in response to stress. The removal of germline stem cells preserves jmjd-3.1 expression, suppresses the accumulation of H3K27me3 at stress gene loci, and maintains the HSR. These findings suggest that competing requirements of the germline and soma dictate organismal stress resistance as animals begin reproduction.
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Affiliation(s)
- Johnathan Labbadia
- Department of Molecular Biosciences, Rice Institute for Biomedical Research, Northwestern University, Evanston, IL 60208, USA
| | - Richard I Morimoto
- Department of Molecular Biosciences, Rice Institute for Biomedical Research, Northwestern University, Evanston, IL 60208, USA.
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46
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GATA-dependent transcriptional and epigenetic control of cardiac lineage specification and differentiation. Cell Mol Life Sci 2015; 72:3871-81. [PMID: 26126786 PMCID: PMC4575685 DOI: 10.1007/s00018-015-1974-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Revised: 06/15/2015] [Accepted: 06/17/2015] [Indexed: 12/14/2022]
Abstract
Heart progenitor cells differentiate into various cell types including pacemaker and working cardiomyocytes. Cell-type specific gene expression is achieved by combinatorial interactions between tissue-specific transcription factors (TFs), co-factors, and chromatin remodelers and DNA binding elements in regulatory regions. Dysfunction of these transcriptional networks may result in congenital heart defects. Functional analysis of the regulatory DNA sequences has contributed substantially to the identification of the transcriptional network components and combinatorial interactions regulating the tissue-specific gene programs. GATA TFs have been identified as central players in these networks. In particular, GATA binding elements have emerged as a platform to recruit broadly active histone modification enzymes and cell-type-specific co-factors to drive cell-type-specific gene programs. Here, we discuss the role of GATA factors in cell fate decisions and differentiation in the developing heart.
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47
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Induced neural stem/precursor cells for fundamental studies and potential application in neurodegenerative diseases. Neurosci Bull 2015; 31:589-600. [PMID: 26077704 DOI: 10.1007/s12264-015-1527-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2015] [Accepted: 04/01/2015] [Indexed: 01/13/2023] Open
Abstract
Recent research has shown that defined sets of exogenous factors are sufficient to convert rodent and human somatic cells directly into induced neural stem cells or neural precursor cells (iNSCs/iNPCs). The process of transdifferentiation bypasses the step of a pluripotent state and reduces the risk of tumorigenesis and genetic instability while retaining the self-renewing capacity. This iNSC/iNPC technology has fueled much excitement in regenerative medicine, as these cells can be differentiated into target cells for re placement therapy for neurodegenerative diseases. Patients' somatic cell-derived iNSCs/iNPCs have also been proposed to serve as disease models with potential value in both fundamental studies and clinical applications. This review focuses on the mechanisms, techniques, and app lications of iNSCs/iNPCs from a series of related studies, as well as further efforts in designing novel strategies using iNSC/iNPC technology and its potential applications in neurodegenerative diseases.
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48
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Heinrich C, Spagnoli FM, Berninger B. In vivo reprogramming for tissue repair. Nat Cell Biol 2015; 17:204-11. [PMID: 25720960 DOI: 10.1038/ncb3108] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Vital organs such as the pancreas and the brain lack the capacity for effective regeneration. To overcome this limitation, an emerging strategy consists of converting resident tissue-specific cells into the cell types that are lost due to disease by a process called in vivo lineage reprogramming. Here we discuss recent breakthroughs in regenerating pancreatic β-cells and neurons from various cell types, and highlight fundamental challenges that need to be overcome for the translation of in vivo lineage reprogramming into therapy.
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Affiliation(s)
- Christophe Heinrich
- INSERM U836, F-38000 Grenoble, France and Univ. Grenoble Alpes, Grenoble Institut des Neurosciences, GIN, F-38000 Grenoble, France
| | | | - Benedikt Berninger
- Institute of Physiological Chemistry and the Focus Program Translational Neuroscience, University Medical Center of the Johannes Gutenberg University Mainz, D-55128 Mainz, Germany, and Physiological Genomics, Institute of Physiology, Ludwig Maximilians University Munich, D-80336 Munich, Germany
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49
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El-Badawy A, El-Badri N. Regulators of pluripotency and their implications in regenerative medicine. STEM CELLS AND CLONING-ADVANCES AND APPLICATIONS 2015; 8:67-80. [PMID: 25960670 PMCID: PMC4410894 DOI: 10.2147/sccaa.s80157] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The ultimate goal of regenerative medicine is to replace damaged tissues with new functioning ones. This can potentially be accomplished by stem cell transplantation. While stem cell transplantation for blood diseases has been increasingly successful, widespread application of stem cell therapy in the clinic has shown limited results. Despite successful efforts to refine existing methodologies and to develop better ones for reprogramming, clinical application of stem cell therapy suffers from issues related to the safety of the transplanted cells, as well as the low efficiency of reprogramming technology. Better understanding of the underlying mechanism(s) involved in pluripotency should accelerate the clinical application of stem cell transplantation for regenerative purposes. This review outlines the main decision-making factors involved in pluripotency, focusing on the role of microRNAs, epigenetic modification, signaling pathways, and toll-like receptors. Of special interest is the role of toll-like receptors in pluripotency, where emerging data indicate that the innate immune system plays a vital role in reprogramming. Based on these data, we propose that nongenetic mechanisms for reprogramming provide a novel and perhaps an essential strategy to accelerate application of regenerative medicine in the clinic.
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Affiliation(s)
- Ahmed El-Badawy
- Center of Excellence for Stem Cells and Regenerative Medicine, Zewail City of Science and Technology, Giza, Egypt
| | - Nagwa El-Badri
- Center of Excellence for Stem Cells and Regenerative Medicine, Zewail City of Science and Technology, Giza, Egypt
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50
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Wang J, Chitturi J, Ge Q, Laskova V, Wang W, Li X, Ding M, Zhen M, Huang X. The C. elegans COE transcription factor UNC-3 activates lineage-specific apoptosis and affects neurite growth in the RID lineage. Development 2015; 142:1447-57. [PMID: 25790851 DOI: 10.1242/dev.119479] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Accepted: 02/17/2015] [Indexed: 12/23/2022]
Abstract
Mechanisms that regulate apoptosis in a temporal and lineage-specific manner remain poorly understood. The COE (Collier/Olf/EBF) transcription factors have been implicated in the development of many cell types, including neurons. Here, we show that the sole Caenorhabditis elegans COE protein, UNC-3, together with a histone acetyltransferase, CBP-1/P300, specifies lineage-specific apoptosis and certain aspects of neurite trajectory. During embryogenesis, the RID progenitor cell gives rise to the RID neuron and RID sister cell; the latter undergoes apoptosis shortly after cell division upon expression of the pro-apoptotic gene egl-1. We observe UNC-3 expression in the RID progenitor, and the absence of UNC-3 results in the failure of the RID lineage to express a Pegl-1::GFP reporter and in the survival of the RID sister cell. Lastly, UNC-3 interacts with CBP-1, and cbp-1 mutants exhibit a similar RID phenotype to unc-3. Thus, in addition to playing a role in neuronal terminal differentiation, UNC-3 is a cell lineage-specific regulator of apoptosis.
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Affiliation(s)
- Jinbo Wang
- State Key Laboratory of Molecular and Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jyothsna Chitturi
- Lunenfeld and Tanebaum Research Institute, University of Toronto, Toronto, Ontario, Canada M5G 1X5
| | - Qinglan Ge
- State Key Laboratory of Molecular and Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China University of Chinese Academy of Sciences, Beijing 100049, China
| | - Valeriya Laskova
- Lunenfeld and Tanebaum Research Institute, University of Toronto, Toronto, Ontario, Canada M5G 1X5
| | - Wei Wang
- State Key Laboratory of Molecular and Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Xia Li
- State Key Laboratory of Molecular and Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Mei Ding
- State Key Laboratory of Molecular and Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Mei Zhen
- Lunenfeld and Tanebaum Research Institute, University of Toronto, Toronto, Ontario, Canada M5G 1X5
| | - Xun Huang
- State Key Laboratory of Molecular and Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
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