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Chen X, Qi Y, Huang Q, Sun C, Zheng Y, Ji L, Shi Y, Cheng X, Li Z, Zheng S, Cao Y, Gu Z, Yu J. Single-cell transcriptome characteristics of testicular terminal epithelium lineages during aging in the Drosophila. Aging Cell 2024; 23:e14057. [PMID: 38044573 PMCID: PMC10928582 DOI: 10.1111/acel.14057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Revised: 11/14/2023] [Accepted: 11/17/2023] [Indexed: 12/05/2023] Open
Abstract
Aging is a complex biological process leading to impaired functions, with a variety of hallmarks. In the testis of Drosophila, the terminal epithelium region is involved in spermatid release and maturation, while its functional diversity and regulatory mechanism remain poorly understood. In this study, we performed single-cell RNA-sequencing analysis (scRNA-seq) to characterize the transcriptomes of terminal epithelium in Drosophila testes at 2-, 10 and 40-Days. Terminal epithelium populations were defined with Metallothionein A (MtnA) and subdivided into six novel sub-cell clusters (EP0-EP5), and a series of marker genes were identified based on their expressions. The data revealed the functional characteristics of terminal epithelium populations, such as tight junction, focal adhesion, bacterial invasion, oxidative stress, mitochondrial function, proteasome, apoptosis and metabolism. Interestingly, we also found that disrupting genes for several relevant pathways in terminal epithelium led to male fertility disorders. Moreover, we also discovered a series of age-biased genes and pseudotime trajectory mediated state-biased genes during terminal epithelium aging. Differentially expressed genes during terminal epithelium aging were mainly participated in the regulation of several common signatures, e.g. mitochondria-related events, protein synthesis and degradation, and metabolic processes. We further explored the Drosophila divergence and selection in the functional constraints of age-biased genes during aging, revealing that age-biased genes in epithelial cells of 2 Days group evolved rapidly and were endowed with greater evolutionary advantages. scRNA-seq analysis revealed the diversity of testicular terminal epithelium populations, providing a gene target resource for further systematic research of their functions during aging.
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Affiliation(s)
- Xia Chen
- Department of Obstetrics and Gynecology, Nantong First People's HospitalAffiliated Hospital 2 of Nantong University; Medical School of Nantong University, Nantong UniversityNantongJiangsuChina
| | - Yujuan Qi
- Clinical Center of Reproductive Medicine, Xuzhou Central HospitalXuzhou Clinical School of Xuzhou Medical UniversityXuzhouChina
| | - Qiuru Huang
- Institute of Reproductive MedicineMedical School of Nantong University, Nantong UniversityNantongChina
| | - Chi Sun
- Department of GeriatricsAffiliated Hospital of Nantong University, Nantong UniversityNantongChina
| | - Yanli Zheng
- Department of Obstetrics and Gynecology, Nantong First People's HospitalAffiliated Hospital 2 of Nantong University; Medical School of Nantong University, Nantong UniversityNantongJiangsuChina
| | - Li Ji
- Institute of Reproductive MedicineMedical School of Nantong University, Nantong UniversityNantongChina
| | - Yi Shi
- Institute of Reproductive MedicineMedical School of Nantong University, Nantong UniversityNantongChina
| | - Xinmeng Cheng
- Institute of Reproductive MedicineMedical School of Nantong University, Nantong UniversityNantongChina
| | - Zhenbei Li
- Clinical Center of Reproductive Medicine, Xuzhou Central HospitalXuzhou Clinical School of Xuzhou Medical UniversityXuzhouChina
| | - Sen Zheng
- Clinical Center of Reproductive Medicine, Xuzhou Central HospitalXuzhou Clinical School of Xuzhou Medical UniversityXuzhouChina
| | - Yijuan Cao
- Clinical Center of Reproductive Medicine, Xuzhou Central HospitalXuzhou Clinical School of Xuzhou Medical UniversityXuzhouChina
| | - Zhifeng Gu
- Department of RheumatologyAffiliated Hospital of Nantong University, Nantong UniversityNantongChina
| | - Jun Yu
- Institute of Reproductive MedicineMedical School of Nantong University, Nantong UniversityNantongChina
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Sreejith P, Kim C. Lin28 is Required for Single Niche Development in the Drosophila Male Gonad. Dev Reprod 2023; 27:221-226. [PMID: 38292237 PMCID: PMC10824566 DOI: 10.12717/dr.2023.27.4.221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Revised: 10/22/2023] [Accepted: 11/23/2023] [Indexed: 02/01/2024]
Abstract
A stem cell niche provides an environment that governs stem cell maintenance and division. Thus, the development of a proper niche is of prime importance to stem cell behaviors. Mechanisms of niche development are beginning to be revealed in the Drosophila male gonad. Niche cells are initially dispersed throughout the gonad, then assemble at its apical tip through the anterior migration of posteriorly located niche cells. The molecular mechanisms of this migration and assembly are still poorly understood. Here we show evidence suggesting that Lin28, an RNA-binding protein and regulator of let7 genesis, might be an intrinsic factor for the anterior migration of niche cells. We found that a dispersed, ectopic niche, a phenotype observed with anterior migration defects, occurs in lin28 mutant gonads. This phenotype is rescued by expression of lin28 in the niche cells. These findings suggest that Lin28 might be required for the anterior migration of niche cells.
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Affiliation(s)
- Perinthottathil Sreejith
- Department of Biomedical Genetics,
University of Rochester Medical Center, Rochester,
NY 14642, USA
| | - Changsoo Kim
- School of Biological Sciences and
Technology, Chonnam National University, Gwangju
61186, Korea
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3
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Bian S, Jiang Y, Dai Z, Wu X, Li B, Wang N, Bian W, Zhong W. Lin28b delays vasculature aging by reducing platelet-derived growth factor-beta resistance in senescent vascular smooth muscle cells. Atherosclerosis 2023; 364:29-38. [PMID: 36529087 DOI: 10.1016/j.atherosclerosis.2022.12.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Revised: 11/12/2022] [Accepted: 12/13/2022] [Indexed: 12/15/2022]
Abstract
BACKGROUND AND AIMS Platelet-derived growth factor-β (PDGFB) is an important mediator of vascular smooth muscle cell (VSMC) proliferation, and PDGFB resistance is observed in senescent VSMCs. Lin28b is a stemness regulator in the embryo; however, its role in vasculature aging and VSMC senescence is unknown. We aimed to investigate whether Lin28b could restore the VSMC response to PDGFB and delay vasculature aging. METHODS ApoE-/- mice were fed a high-fat diet for different weeks to establish an aging model. PDGFB resistance was observed using EdU staining in vessel culture in vitro. Quantitative polymerase chain reaction and in situ hybridization were used to detect let-7 expression. Senescence was identified by Western blotting, senescence-associated beta-galactosidase activity or Sudan Black B staining, and VSMC function was determined using CCK-8, migration, and enzyme-linked immunosorbent assays. RESULTS Vessels from aged mice showed poor responses to PDGFB stimulation compared with those from young mice; similar results were found in senescent VSMCs. The expression levels of Lin28b and PDGF receptor-β were downregulated in aging vasculature and senescent VSMCs, whereas let-7 family levels increased with aging and VSMC passage growth. Transfection of VSMCs with let-7c induced PDGFB resistance and accelerated VSMC senescence, whereas blocking let-7c restored PDGFB reactions in VSMCs. Overexpression of Lin28b protein by lentivirus resulted in the restoration of PDGFB reactions and delayed VSMC senescence, which was blocked by a let-7c mimic. CONCLUSIONS This study reveals the role of Lin28b in delaying vasculature aging by decreasing senescent VSMC PDGFB resistance mediated by let-7.
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Affiliation(s)
- Shihui Bian
- Department of Geriatrics, Affiliated Renmin Hospital of Jiangsu University, Zhenjiang, Jiangsu, PR China
| | - Yu Jiang
- Department of Cardiology, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu, PR China
| | - Zhiyin Dai
- Department of Cardiology, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu, PR China
| | - Xi Wu
- Department of Geriatrics, Affiliated Renmin Hospital of Jiangsu University, Zhenjiang, Jiangsu, PR China
| | - Bo Li
- Department of Cardiology, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu, PR China
| | - Nan Wang
- Department of Geriatrics, Affiliated Renmin Hospital of Jiangsu University, Zhenjiang, Jiangsu, PR China
| | - Wenyan Bian
- Department of Geriatrics, Affiliated Renmin Hospital of Jiangsu University, Zhenjiang, Jiangsu, PR China
| | - Wei Zhong
- Department of Cardiology, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu, PR China.
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Imp interacts with Lin28 to regulate adult stem cell proliferation in the Drosophila intestine. PLoS Genet 2022; 18:e1010385. [PMID: 36070313 PMCID: PMC9484684 DOI: 10.1371/journal.pgen.1010385] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Revised: 09/19/2022] [Accepted: 08/18/2022] [Indexed: 11/30/2022] Open
Abstract
Stem cells are essential for the development and long-term maintenance of tissues and organisms. Preserving tissue homeostasis requires exquisite control of all aspects of stem cell function: cell potency, proliferation, fate decision and differentiation. RNA binding proteins (RBPs) are essential components of the regulatory network that control gene expression in stem cells to maintain self-renewal and long-term homeostasis in adult tissues. While the function of many RBPs may have been characterized in various stem cell populations, how these interact and are organized in genetic networks remains largely elusive. In this report, we show that the conserved RNA binding protein IGF2 mRNA binding protein (Imp) is expressed in intestinal stem cells (ISCs) and progenitors in the adult Drosophila midgut. We demonstrate that Imp is required cell autonomously to maintain stem cell proliferative activity under normal epithelial turnover and in response to tissue damage. Mechanistically, we show that Imp cooperates and directly interacts with Lin28, another highly conserved RBP, to regulate ISC proliferation. We found that both proteins bind to and control the InR mRNA, a critical regulator of ISC self-renewal. Altogether, our data suggests that Imp and Lin28 are part of a larger gene regulatory network controlling gene expression in ISCs and required to maintain epithelial homeostasis. Stem cells are essential to maintain healthy organs. However, dysregulation of their function is a potential major driver of diseases, including cancer and neurodegeneration, and significantly contributes to the aging process. For these reasons, numerous mechanisms control the ability of stem cells to divide and give rise to functional daughter cells. In this study, we used the Drosophila fruitfly as a genetically amenable experimental model to characterize the function of a conserved protein, the IGF2 mRNA binding protein, in the regulation of adult intestinal stem cells. We found that it is essential for stem cell proliferation under normal conditions and in response to tissue damage. We also report that it interacts with another known regulator, Lin28. Importantly, these two factors largely control stem cell biology and development in mammals, including humans, and are often dysregulated in cancer. This suggests that our work is shedding new light on the conserved mechanisms that maintain long-term stem cell function across organisms.
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Wang Y, Zhao J, Chen S, Li D, Yang J, Zhao X, Qin M, Guo M, Chen C, He Z, Zhou Y, Xu L. Let-7 as a Promising Target in Aging and Aging-Related Diseases: A Promise or a Pledge. Biomolecules 2022; 12:biom12081070. [PMID: 36008964 PMCID: PMC9406090 DOI: 10.3390/biom12081070] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 07/28/2022] [Accepted: 07/29/2022] [Indexed: 12/10/2022] Open
Abstract
The abnormal regulation and expression of microRNA (miRNA) are closely related to the aging process and the occurrence and development of aging-related diseases. Lethal-7 (let-7) was discovered in Caenorhabditis elegans (C. elegans) and plays an important role in development by regulating cell fate regulators. Accumulating evidence has shown that let-7 is elevated in aging tissues and participates in multiple pathways that regulate the aging process, including affecting tissue stem cell function, body metabolism, and various aging-related diseases (ARDs). Moreover, recent studies have found that let-7 plays an important role in the senescence of B cells, suggesting that let-7 may also participate in the aging process by regulating immune function. Therefore, these studies show the diversity and complexity of let-7 expression and regulatory functions during aging. In this review, we provide a detailed overview of let-7 expression regulation as well as its role in different tissue aging and aging-related diseases, which may provide new ideas for enriching the complex expression regulation mechanism and pathobiological function of let-7 in aging and related diseases and ultimately provide help for the development of new therapeutic strategies.
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Affiliation(s)
- Ya Wang
- Special Key Laboratory of Gene Detection and Therapy & Base for Talents in Biotherapy of Guizhou Province, Zunyi 563000, China; (Y.W.); (J.Z.); (S.C.); (D.L.); (J.Y.); (X.Z.); (M.Q.); (M.G.); (C.C.)
- Department of Immunology, Zunyi Medical University, Zunyi 563000, China
| | - Juanjuan Zhao
- Special Key Laboratory of Gene Detection and Therapy & Base for Talents in Biotherapy of Guizhou Province, Zunyi 563000, China; (Y.W.); (J.Z.); (S.C.); (D.L.); (J.Y.); (X.Z.); (M.Q.); (M.G.); (C.C.)
- Department of Immunology, Zunyi Medical University, Zunyi 563000, China
| | - Shipeng Chen
- Special Key Laboratory of Gene Detection and Therapy & Base for Talents in Biotherapy of Guizhou Province, Zunyi 563000, China; (Y.W.); (J.Z.); (S.C.); (D.L.); (J.Y.); (X.Z.); (M.Q.); (M.G.); (C.C.)
- Department of Immunology, Zunyi Medical University, Zunyi 563000, China
| | - Dongmei Li
- Special Key Laboratory of Gene Detection and Therapy & Base for Talents in Biotherapy of Guizhou Province, Zunyi 563000, China; (Y.W.); (J.Z.); (S.C.); (D.L.); (J.Y.); (X.Z.); (M.Q.); (M.G.); (C.C.)
- Department of Immunology, Zunyi Medical University, Zunyi 563000, China
| | - Jing Yang
- Special Key Laboratory of Gene Detection and Therapy & Base for Talents in Biotherapy of Guizhou Province, Zunyi 563000, China; (Y.W.); (J.Z.); (S.C.); (D.L.); (J.Y.); (X.Z.); (M.Q.); (M.G.); (C.C.)
- Department of Immunology, Zunyi Medical University, Zunyi 563000, China
| | - Xu Zhao
- Special Key Laboratory of Gene Detection and Therapy & Base for Talents in Biotherapy of Guizhou Province, Zunyi 563000, China; (Y.W.); (J.Z.); (S.C.); (D.L.); (J.Y.); (X.Z.); (M.Q.); (M.G.); (C.C.)
- Department of Immunology, Zunyi Medical University, Zunyi 563000, China
| | - Ming Qin
- Special Key Laboratory of Gene Detection and Therapy & Base for Talents in Biotherapy of Guizhou Province, Zunyi 563000, China; (Y.W.); (J.Z.); (S.C.); (D.L.); (J.Y.); (X.Z.); (M.Q.); (M.G.); (C.C.)
- Department of Immunology, Zunyi Medical University, Zunyi 563000, China
| | - Mengmeng Guo
- Special Key Laboratory of Gene Detection and Therapy & Base for Talents in Biotherapy of Guizhou Province, Zunyi 563000, China; (Y.W.); (J.Z.); (S.C.); (D.L.); (J.Y.); (X.Z.); (M.Q.); (M.G.); (C.C.)
- Department of Immunology, Zunyi Medical University, Zunyi 563000, China
| | - Chao Chen
- Special Key Laboratory of Gene Detection and Therapy & Base for Talents in Biotherapy of Guizhou Province, Zunyi 563000, China; (Y.W.); (J.Z.); (S.C.); (D.L.); (J.Y.); (X.Z.); (M.Q.); (M.G.); (C.C.)
- Department of Immunology, Zunyi Medical University, Zunyi 563000, China
| | - Zhixu He
- The Collaborative Innovation Center of Tissue Damage Repair and Regeneration Medicine of Zunyi Medical University, Zunyi 563000, China;
| | - Ya Zhou
- Special Key Laboratory of Gene Detection and Therapy & Base for Talents in Biotherapy of Guizhou Province, Zunyi 563000, China; (Y.W.); (J.Z.); (S.C.); (D.L.); (J.Y.); (X.Z.); (M.Q.); (M.G.); (C.C.)
- Department of Medical Physics, Zunyi Medical University, Zunyi 563000, China
- Correspondence: (Y.Z.); (L.X.)
| | - Lin Xu
- Special Key Laboratory of Gene Detection and Therapy & Base for Talents in Biotherapy of Guizhou Province, Zunyi 563000, China; (Y.W.); (J.Z.); (S.C.); (D.L.); (J.Y.); (X.Z.); (M.Q.); (M.G.); (C.C.)
- Department of Immunology, Zunyi Medical University, Zunyi 563000, China
- Correspondence: (Y.Z.); (L.X.)
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Reprogramming neurons for regeneration: The fountain of youth. Prog Neurobiol 2022; 214:102284. [PMID: 35533809 DOI: 10.1016/j.pneurobio.2022.102284] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Revised: 04/03/2022] [Accepted: 05/02/2022] [Indexed: 01/22/2023]
Abstract
Neurons in the central nervous system (CNS) are terminally differentiated cells that gradually lose their ability to support regeneration during maturation due to changes in transcriptomic and chromatin landscape. Similar transcriptomic changes also occur during development when stem cells differentiate into different types of somatic cells. Importantly, differentiated cells can be reprogrammed back to induced pluripotent stems cells (iPSCs) via global epigenetic remodeling by combined overexpression of pluripotent reprogramming factors, including Oct4, Sox2, Klf4, c-Myc, Nanog, and/or Lin28. Moreover, recent findings showed that many proneural transcription factors were able to convert non-neural somatic cells into neurons bypassing the pluripotent stage via direct reprogramming. Interestingly, many of these factors have recently been identified as key regulators of CNS neural regeneration. Recent studies indicated that these factors could rejuvenate mature CNS neurons back to a younger state through cellular state reprogramming, thus favoring regeneration. Here we will review some recent findings regarding the roles of genetic cellular state reprogramming in regulation of neural regeneration and explore the potential underlying molecular mechanisms. Moreover, by using newly emerging techniques, such as multiomics sequencing with big data analysis and Crispr-based gene editing, we will discuss future research directions focusing on better revealing cellular state reprogramming-induced remodeling of chromatin landscape and potential translational application.
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7
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LIN28 Family in Testis: Control of Cell Renewal, Maturation, Fertility and Aging. Int J Mol Sci 2022; 23:ijms23137245. [PMID: 35806250 PMCID: PMC9266904 DOI: 10.3390/ijms23137245] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Revised: 06/20/2022] [Accepted: 06/25/2022] [Indexed: 12/12/2022] Open
Abstract
Male reproductive development starts early in the embryogenesis with somatic and germ cell differentiation in the testis. The LIN28 family of RNA-binding proteins promoting pluripotency has two members—LIN28A and LIN28B. Their function in the testis has been investigated but many questions about their exact role based on the expression patterns remain unclear. LIN28 expression is detected in the gonocytes and the migrating, mitotically active germ cells of the fetal testis. Postnatal expression of LIN28 A and B showed differential expression, with LIN28A expressed in the undifferentiated spermatogonia and LIN28B in the elongating spermatids and Leydig cells. LIN28 interferes with many signaling pathways, leading to cell proliferation, and it is involved in important testicular physiological processes, such as cell renewal, maturation, fertility, and aging. In addition, aberrant LIN28 expression is associated with testicular cancer and testicular disorders, such as hypogonadotropic hypogonadism and Klinefelter’s syndrome. This comprehensive review encompasses current knowledge of the function of LIN28 paralogs in testis and other tissues and cells because many studies suggest LIN28AB as a promising target for developing novel therapeutic agents.
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8
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To V, Kim HJ, Jang W, Sreejith P, Kim C. Lin28 and Imp are Required for Stability of Bowl Transcripts in Hub
Cells of the Drosophila Testis. Dev Reprod 2021; 25:313-319. [PMID: 35141457 PMCID: PMC8807131 DOI: 10.12717/dr.2021.25.4.313] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 11/28/2021] [Accepted: 12/15/2021] [Indexed: 11/24/2022]
Abstract
Hub cells comprise a niche for germline stem cells and cyst stem cells in the
Drosophila testis. Hub cells arise from common somatic
gonadal precursors in embryos, but the mechanism of their specification is still
poorly understood. Here we find that RNA binding proteins Lin28 and Imp mediate
transcript stability of Bowl, a known hub specification factor; Bowl transcripts
were reduced in the testis of Lin28 and Imp mutants, and also when RNA-mediated
interference against Lin28 or Imp was expressed in hub cells. In tissue culture
Luciferase assays involving the Bowl 3’UTR, stability of Luc reporter
transcripts depended on the Bowl 3’UTR and required Lin28 and Imp. Our
findings suggest that proper Bowl function during hub cell specification
requires Lin28 and Imp in the testis hub cells.
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Affiliation(s)
- Van To
- School of Biological Sciences and
Technology, Chonnam National University, Gwangju
61186, Korea
| | - Hyun Ju Kim
- School of Biological Sciences and
Technology, Chonnam National University, Gwangju
61186, Korea
| | - Wijeong Jang
- School of Biological Sciences and
Technology, Chonnam National University, Gwangju
61186, Korea
| | | | - Changsoo Kim
- School of Biological Sciences and
Technology, Chonnam National University, Gwangju
61186, Korea
- Corresponding author Changsoo Kim, School of
Biological Sciences and Technology, Chonnam National University, Gwangju 61186,
Korea. Tel: +82-62-530-5201, E-mail:
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Herrera SC, Sainz de la Maza D, Grmai L, Margolis S, Plessel R, Burel M, O'Connor M, Amoyel M, Bach EA. Proliferative stem cells maintain quiescence of their niche by secreting the Activin inhibitor Follistatin. Dev Cell 2021; 56:2284-2294.e6. [PMID: 34363758 PMCID: PMC8387025 DOI: 10.1016/j.devcel.2021.07.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 05/14/2021] [Accepted: 07/15/2021] [Indexed: 12/20/2022]
Abstract
Aging causes stem cell dysfunction as a result of extrinsic and intrinsic changes. Decreased function of the stem cell niche is an important contributor to this dysfunction. We use the Drosophila testis to investigate what factors maintain niche cells. The testis niche comprises quiescent “hub” cells and supports two mitotic stem cell pools: germline stem cells and somatic cyst stem cells (CySCs). We identify the cell-cycle-responsive Dp/E2f1 transcription factor as a crucial non-autonomous regulator required in CySCs to maintain hub cell quiescence. Dp/E2f1 inhibits local Activin ligands through production of the Activin antagonist Follistatin (Fs). Inactivation of Dp/E2f1 or Fs in CySCs or promoting Activin receptor signaling in hub cells causes transdifferentiation of hub cells into fully functional CySCs. This Activin-dependent communication between CySCs and hub regulates the physiological decay of the niche with age and demonstrates that hub cell quiescence results from signals from surrounding stem cells. Dp/E2f1 is required in stem cells to non-autonomously maintain niche quiescence Dp/E2f1 promotes niche quiescence through Fs, an Activin antagonist Activin signaling in niche cells causes transdifferentiation into functional stem cells Fs in stem cells regulates the physiological decay of the niche with age
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Affiliation(s)
- Salvador C Herrera
- Biochemistry and Molecular Pharmacology, NYU Grossman School of Medicine, New York, NY 10016, USA; Centro Andaluz de Biología del Desarrollo, CSIC/Universidad Pablo de Olavide/JA, Carretera de Utrera km 1, 41013 Sevilla, Spain
| | - Diego Sainz de la Maza
- Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK
| | - Lydia Grmai
- Biochemistry and Molecular Pharmacology, NYU Grossman School of Medicine, New York, NY 10016, USA
| | - Shally Margolis
- Biochemistry and Molecular Pharmacology, NYU Grossman School of Medicine, New York, NY 10016, USA
| | - Rebecca Plessel
- Biochemistry and Molecular Pharmacology, NYU Grossman School of Medicine, New York, NY 10016, USA
| | - Michael Burel
- Biochemistry and Molecular Pharmacology, NYU Grossman School of Medicine, New York, NY 10016, USA
| | - Michael O'Connor
- Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, MN 55455, USA
| | - Marc Amoyel
- Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK.
| | - Erika A Bach
- Biochemistry and Molecular Pharmacology, NYU Grossman School of Medicine, New York, NY 10016, USA.
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