1
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Vidaurre V, Song A, Li T, Ku WL, Zhao K, Qian J, Chen X. The Drosophila histone methyltransferase SET1 coordinates multiple signaling pathways in regulating male germline stem cell maintenance and differentiation. Development 2024; 151:dev202729. [PMID: 39007366 DOI: 10.1242/dev.202729] [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: 01/25/2024] [Accepted: 07/08/2024] [Indexed: 07/16/2024]
Abstract
Many tissue-specific adult stem cell lineages maintain a balance between proliferation and differentiation. Here, we study how the H3K4me3 methyltransferase Set1 regulates early-stage male germ cells in Drosophila. Early-stage germline-specific knockdown of Set1 results in temporally progressive defects, arising as germ cell loss and developing into overpopulated early-stage germ cells. These germline defects also impact the niche architecture and cyst stem cell lineage non-cell-autonomously. Additionally, wild-type Set1, but not the catalytically inactive Set1, rescues the Set1 knockdown phenotypes, highlighting the functional importance of the methyltransferase activity of Set1. Further, RNA-sequencing experiments reveal key signaling pathway components, such as the JAK-STAT pathway gene Stat92E and the BMP pathway gene Mad, which are upregulated upon Set1 knockdown. Genetic interaction assays support the functional relationships between Set1 and JAK-STAT or BMP pathways, as both Stat92E and Mad mutations suppress the Set1 knockdown phenotypes. These findings enhance our understanding of the balance between proliferation and differentiation in an adult stem cell lineage. The phenotype of germ cell loss followed by over-proliferation when inhibiting a histone methyltransferase also raises concerns about using their inhibitors in cancer therapy.
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Affiliation(s)
- Velinda Vidaurre
- Department of Biology, The Johns Hopkins University, Baltimore, MD 21218, USA
| | - Annabelle Song
- Department of Biology, The Johns Hopkins University, Baltimore, MD 21218, USA
| | - Taibo Li
- Department of Biology, The Johns Hopkins University, Baltimore, MD 21218, USA
| | - Wai Lim Ku
- Laboratory of Epigenome Biology, Systems Biology Center, National Heart, Lung and Blood Institute, NIH, Bethesda, MD 20814, USA
| | - Keji Zhao
- Laboratory of Epigenome Biology, Systems Biology Center, National Heart, Lung and Blood Institute, NIH, Bethesda, MD 20814, USA
| | - Jiang Qian
- Department of Ophthalmology, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Xin Chen
- Department of Biology, The Johns Hopkins University, Baltimore, MD 21218, USA
- Howard Hughes Medical Institute, 4000 Jones Bridge Road, Chevy Chase, MD 20815, USA
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2
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Snedeker J, Davis BEM, Ranjan R, Wooten M, Blundon J, Chen X. Reduced Levels of Lagging Strand Polymerases Shape Stem Cell Chromatin. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.26.591383. [PMID: 38746451 PMCID: PMC11092439 DOI: 10.1101/2024.04.26.591383] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2024]
Abstract
Stem cells display asymmetric histone inheritance while non-stem progenitor cells exhibit symmetric patterns in the Drosophila male germline lineage. Here, we report that components involved in lagging strand synthesis, such as DNA polymerase α and δ (Polα and Polδ), have significantly reduced levels in stem cells compared to progenitor cells. Compromising Polα genetically induces the replication-coupled histone incorporation pattern in progenitor cells to be indistinguishable from that in stem cells, which can be recapitulated using a Polα inhibitor in a concentration-dependent manner. Furthermore, stem cell-derived chromatin fibers display a higher degree of old histone recycling by the leading strand compared to progenitor cell-derived chromatin fibers. However, upon reducing Polα levels in progenitor cells, the chromatin fibers now display asymmetric old histone recycling just like GSC-derived fibers. The old versus new histone asymmetry is comparable between stem cells and progenitor cells at both S-phase and M-phase. Together, these results indicate that developmentally programmed expression of key DNA replication components is important to shape stem cell chromatin. Furthermore, manipulating one crucial DNA replication component can induce replication-coupled histone dynamics in non-stem cells in a manner similar to that in stem cells.
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Affiliation(s)
- Jonathan Snedeker
- Department of Biology, The Johns Hopkins University, Baltimore, MD 21218, USA
| | - Brendon E. M. Davis
- Department of Biology, The Johns Hopkins University, Baltimore, MD 21218, USA
| | - Rajesh Ranjan
- Department of Biology, The Johns Hopkins University, Baltimore, MD 21218, USA
- Howard Hughes Medical Institute, Department of Biology, The Johns Hopkins University, 3400 North Charles Street, Baltimore, Baltimore, MD 21218, USA
| | - Matthew Wooten
- Department of Biology, The Johns Hopkins University, Baltimore, MD 21218, USA
- Current address: Fred Hutchinson Cancer Research Center, Seattle, WA 98109-1024, USA
| | - Joshua Blundon
- Department of Biology, The Johns Hopkins University, Baltimore, MD 21218, USA
| | - Xin Chen
- Department of Biology, The Johns Hopkins University, Baltimore, MD 21218, USA
- Howard Hughes Medical Institute, Department of Biology, The Johns Hopkins University, 3400 North Charles Street, Baltimore, Baltimore, MD 21218, USA
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3
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Glazenburg MM, Hettema NM, Laan L, Remy O, Laloux G, Brunet T, Chen X, Tee YH, Wen W, Rizvi MS, Jolly MK, Riddell M. Perspectives on polarity - exploring biological asymmetry across scales. J Cell Sci 2024; 137:jcs261987. [PMID: 38441500 DOI: 10.1242/jcs.261987] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/07/2024] Open
Abstract
In this Perspective, Journal of Cell Science invited researchers working on cell and tissue polarity to share their thoughts on unique, emerging or open questions relating to their field. The goal of this article is to feature 'voices' from scientists around the world and at various career stages, to bring attention to innovative and thought-provoking topics of interest to the cell biology community. These voices discuss intriguing questions that consider polarity across scales, evolution, development and disease. What can yeast and protists tell us about the evolution of cell and tissue polarity in animals? How are cell fate and development influenced by emerging dynamics in cell polarity? What can we learn from atypical and extreme polarity systems? How can we arrive at a more unified biophysical understanding of polarity? Taken together, these pieces demonstrate the broad relevance of the fascinating phenomenon of cell polarization to diverse fundamental biological questions.
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Affiliation(s)
- Marieke Margaretha Glazenburg
- Department of Bionanoscience, Kavli Institute of Nanoscience Delft, Delft University of Technology, Delft, 2629 HZ, The Netherlands
| | - Nynke Marije Hettema
- Department of Bionanoscience, Kavli Institute of Nanoscience Delft, Delft University of Technology, Delft, 2629 HZ, The Netherlands
| | - Liedewij Laan
- Department of Bionanoscience, Kavli Institute of Nanoscience Delft, Delft University of Technology, Delft, 2629 HZ, The Netherlands
| | - Ophélie Remy
- Institut de Duve, UCLouvain, 75 avenue Hippocrate, 1200 Brussels, Belgium
| | - Géraldine Laloux
- Institut de Duve, UCLouvain, 75 avenue Hippocrate, 1200 Brussels, Belgium
| | - Thibaut Brunet
- Institut Pasteur, Université Paris-Cité, CNRS UMR 3691, Evolutionary Cell Biology and Evolution of Morphogenesis Unit, 25-28 rue du docteur Roux, 75015 Paris, France
| | - Xin Chen
- Howard Hughes Medical Institute and Department of Biology, Johns Hopkins University, Levi Hall 137, 3400 North Charles Street, Baltimore, MD 21218-2685, USA
| | - Yee Han Tee
- Mechanobiology Institute, National University of Singapore, Singapore 117411, Singapore
| | - Wenyu Wen
- Department of Neurosurgery, Huashan Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Biomedical Sciences, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China
| | - Mohd Suhail Rizvi
- Department of Biomedical Engineering, Indian Institute of Technology Hyderabad, Sangareddy 502284, India
| | - Mohit Kumar Jolly
- Department of Bioengineering, Indian Institute of Science, Bangalore 560012, India
| | - Meghan Riddell
- Department of Physiology and Department of Obstetrics and Gynecology, University of Alberta, Edmonton, AB, T6G 2S2, Canada
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4
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Xu MJ, Jordan PW. SMC5/6 Promotes Replication Fork Stability via Negative Regulation of the COP9 Signalosome. Int J Mol Sci 2024; 25:952. [PMID: 38256025 PMCID: PMC10815603 DOI: 10.3390/ijms25020952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Revised: 01/06/2024] [Accepted: 01/10/2024] [Indexed: 01/24/2024] Open
Abstract
It is widely accepted that DNA replication fork stalling is a common occurrence during cell proliferation, but there are robust mechanisms to alleviate this and ensure DNA replication is completed prior to chromosome segregation. The SMC5/6 complex has consistently been implicated in the maintenance of replication fork integrity. However, the essential role of the SMC5/6 complex during DNA replication in mammalian cells has not been elucidated. In this study, we investigate the molecular consequences of SMC5/6 loss at the replication fork in mouse embryonic stem cells (mESCs), employing the auxin-inducible degron (AID) system to deplete SMC5 acutely and reversibly in the defined cellular contexts of replication fork stall and restart. In SMC5-depleted cells, we identify a defect in the restart of stalled replication forks, underpinned by excess MRE11-mediated fork resection and a perturbed localization of fork protection factors to the stalled fork. Previously, we demonstrated a physical and functional interaction of SMC5/6 with the COP9 signalosome (CSN), a cullin deneddylase that enzymatically regulates cullin ring ligase (CRL) activity. Employing a combination of DNA fiber techniques, the AID system, small-molecule inhibition assays, and immunofluorescence microscopy analyses, we show that SMC5/6 promotes the localization of fork protection factors to stalled replication forks by negatively modulating the COP9 signalosome (CSN). We propose that the SMC5/6-mediated modulation of the CSN ensures that CRL activity and their roles in DNA replication fork stabilization are maintained to allow for efficient replication fork restart when a replication fork stall is alleviated.
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Affiliation(s)
- Michelle J. Xu
- Department of Biochemistry and Molecular Biology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD 21205, USA
| | - Philip W. Jordan
- Department of Biochemistry and Molecular Biology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD 21205, USA
- Department of Biochemistry and Molecular Biology, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA
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5
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Zion E, Chen X. Studying histone inheritance in different systems using imaging-based methods and perspectives. Biochem Soc Trans 2023; 51:1035-1046. [PMID: 37171077 PMCID: PMC10317187 DOI: 10.1042/bst20220983] [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: 03/07/2023] [Revised: 04/26/2023] [Accepted: 04/28/2023] [Indexed: 05/13/2023]
Abstract
Understanding cell identity is critically important in the fields of cell and developmental biology. During cell division, a mother cell duplicates the genetic material and cellular components to give rise to two daughter cells. While both cells receive the same genetic information, they can take on similar or different cell fates, resulting from a symmetric or asymmetric division. These fates can be modulated by epigenetic mechanisms that can alter gene expression without changing genetic information. Histone proteins, which wrap DNA into fundamental units of chromatin, are major carriers of epigenetic information and can directly influence gene expression and other cellular functions through their interactions with DNA. While it has been well studied how the genetic information is duplicated and segregated, how epigenetic information, such as histones, are inherited through cell division is still an area of investigation. Since canonical histone proteins are incorporated into chromatin during DNA replication and can be modified over time, it is important to study their inheritance within the context of the cell cycle. Here, we outline the biological basis of histone inheritance as well as the imaging-based experimental design that can be used to study this process. Furthermore, we discuss various studies that have investigated this phenomenon with the focus on asymmetrically dividing cells in different systems. This synopsis provides insight into histone inheritance within the context of the cell cycle, along with the technical methods and considerations that must be taken when studying this process in vivo.
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Affiliation(s)
- Emily Zion
- Department of Biology, The Johns Hopkins University, 3400 N. Charles St., Baltimore, MD 21218, U.S.A
| | - Xin Chen
- Department of Biology, The Johns Hopkins University, 3400 N. Charles St., Baltimore, MD 21218, U.S.A
- Howard Hughes Medical Institute, Department of Biology, The Johns Hopkins University, 3400 N. Charles St., Baltimore, MD 21218, U.S.A
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Chandrasekhara C, Ranjan R, Urban JA, Davis BEM, Ku WL, Snedeker J, Zhao K, Chen X. A single N-terminal amino acid determines the distinct roles of histones H3 and H3.3 in the Drosophila male germline stem cell lineage. PLoS Biol 2023; 21:e3002098. [PMID: 37126497 PMCID: PMC10174566 DOI: 10.1371/journal.pbio.3002098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 05/11/2023] [Accepted: 03/29/2023] [Indexed: 05/02/2023] Open
Abstract
Adult stem cells undergo asymmetric cell divisions to produce 2 daughter cells with distinct cell fates: one capable of self-renewal and the other committed for differentiation. Misregulation of this delicate balance can lead to cancer and tissue degeneration. During asymmetric division of Drosophila male germline stem cells (GSCs), preexisting (old) and newly synthesized histone H3 are differentially segregated, whereas old and new histone variant H3.3 are more equally inherited. However, what underlies these distinct inheritance patterns remains unknown. Here, we report that the N-terminal tails of H3 and H3.3 are critical for their inheritance patterns, as well as GSC maintenance and proper differentiation. H3 and H3.3 differ at the 31st position in their N-termini with Alanine for H3 and Serine for H3.3. By swapping these 2 amino acids, we generated 2 mutant histones (i.e., H3A31S and H3.3S31A). Upon expressing them in the early-stage germline, we identified opposing phenotypes: overpopulation of early-stage germ cells in the H3A31S-expressing testes and significant germ cell loss in testes expressing the H3.3S31A. Asymmetric H3 inheritance is disrupted in the H3A31S-expressing GSCs, due to misincorporation of old histones between sister chromatids during DNA replication. Furthermore, H3.3S31A mutation accelerates old histone turnover in the GSCs. Finally, using a modified Chromatin Immunocleavage assay on early-stage germ cells, we found that H3A31S has enhanced occupancy at promoters and transcription starting sites compared with H3, while H3.3S31A is more enriched at transcriptionally silent intergenic regions compared to H3.3. Overall, these results suggest that the 31st amino acids for both H3 and H3.3 are critical for their proper genomic occupancy and function. Together, our findings indicate a critical role for the different amino acid composition of the N-terminal tails between H3 and H3.3 in an endogenous stem cell lineage and provide insights into the importance of proper histone inheritance in specifying cell fates and regulating cellular differentiation.
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Affiliation(s)
- Chinmayi Chandrasekhara
- Department of Biology, The Johns Hopkins University, Baltimore, Baltimore, Maryland, United States of America
| | - Rajesh Ranjan
- Department of Biology, The Johns Hopkins University, Baltimore, Baltimore, Maryland, United States of America
- Howard Hughes Medical Institute, Department of Biology, The Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Jennifer A. Urban
- Department of Biology, The Johns Hopkins University, Baltimore, Baltimore, Maryland, United States of America
| | - Brendon E. M. Davis
- Department of Biology, The Johns Hopkins University, Baltimore, Baltimore, Maryland, United States of America
| | - Wai Lim Ku
- Systems Biology Center, National Heart, Lung and Blood Institute, NIH, Bethesda, Maryland, United States of America
| | - Jonathan Snedeker
- Department of Biology, The Johns Hopkins University, Baltimore, Baltimore, Maryland, United States of America
| | - Keji Zhao
- Systems Biology Center, National Heart, Lung and Blood Institute, NIH, Bethesda, Maryland, United States of America
| | - Xin Chen
- Department of Biology, The Johns Hopkins University, Baltimore, Baltimore, Maryland, United States of America
- Howard Hughes Medical Institute, Department of Biology, The Johns Hopkins University, Baltimore, Maryland, United States of America
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7
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Gleason RJ, Chen X. Epigenetic dynamics during germline development: insights from Drosophila and C. elegans. Curr Opin Genet Dev 2023; 78:102017. [PMID: 36549194 PMCID: PMC10100592 DOI: 10.1016/j.gde.2022.102017] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 11/08/2022] [Accepted: 11/22/2022] [Indexed: 12/24/2022]
Abstract
Gametogenesis produces the only cell type within a metazoan that contributes both genetic and epigenetic information to the offspring. Extensive epigenetic dynamics are required to express or repress gene expression in a precise spatiotemporal manner. On the other hand, early embryos must be extensively reprogrammed as they begin a new life cycle, involving intergenerational epigenetic inheritance. Seminal work in both Drosophila and C. elegans has elucidated the role of various regulators of epigenetic inheritance, including (1) histones, (2) histone-modifying enzymes, and (3) small RNA-dependent epigenetic regulation in the maintenance of germline identity. This review highlights recent discoveries of epigenetic regulation during the stepwise changes of transcription and chromatin structure that takes place during germline stem cell self-renewal, maintenance of germline identity, and intergenerational epigenetic inheritance. Findings from these two species provide precedence and opportunity to extend relevant studies to vertebrates.
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Affiliation(s)
- Ryan J. Gleason
- Department of Biology, The Johns Hopkins University, 3400 N. Charles St., Baltimore, MD 21218, USA
| | - Xin Chen
- HHMI, Department of Biology, The Johns Hopkins University, 3400 N. Charles St., Baltimore, MD 21218, USA
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8
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Ranjan R, Chen X. Quantitative imaging of chromatin inheritance using a dual-color histone in Drosophila germinal stem cells. STAR Protoc 2022; 3:101811. [PMID: 36386868 PMCID: PMC9640340 DOI: 10.1016/j.xpro.2022.101811] [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: 11/11/2022] Open
Abstract
We detail a stepwise protocol for the investigation and quantification of chromatin features during asymmetric cell division (ACD) of Drosophila germline stem cells (GSCs). We describe the use of a dual-color histone to study the inheritance of new and old histones. We detail steps for imaging and analysis of sister chromatid condensation dynamics and nucleosome density changes. In addition, this protocol could be applied to identify stem cells, which can be challenging to identify in intact tissues. For complete details on the use and execution of this protocol, please refer to Tran et al. (2012), Ranjan et al. (2019), and Ranjan et al. (2022).
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Affiliation(s)
- Rajesh Ranjan
- Howard Hughes Medical Institute, Department of Biology, The Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218-2685, USA; Department of Biology, The Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218-2685, USA.
| | - Xin Chen
- Howard Hughes Medical Institute, Department of Biology, The Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218-2685, USA; Department of Biology, The Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218-2685, USA.
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9
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Urban JA, Ranjan R, Chen X. Asymmetric Histone Inheritance: Establishment, Recognition, and Execution. Annu Rev Genet 2022; 56:113-143. [PMID: 35905975 PMCID: PMC10054593 DOI: 10.1146/annurev-genet-072920-125226] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The discovery of biased histone inheritance in asymmetrically dividing Drosophila melanogaster male germline stem cells demonstrates one means to produce two distinct daughter cells with identical genetic material. This inspired further studies in different systems, which revealed that this phenomenon may be a widespread mechanism to introduce cellular diversity. While the extent of asymmetric histone inheritance could vary among systems, this phenomenon is proposed to occur in three steps: first, establishment of histone asymmetry between sister chromatids during DNA replication; second, recognition of sister chromatids carrying asymmetric histone information during mitosis; and third, execution of this asymmetry in the resulting daughter cells. By compiling the current knowledge from diverse eukaryotic systems, this review comprehensively details and compares known chromatin factors, mitotic machinery components, and cell cycle regulators that may contribute to each of these three steps. Also discussed are potential mechanisms that introduce and regulate variable histone inheritance modes and how these different modes may contribute to cell fate decisions in multicellular organisms.
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Affiliation(s)
- Jennifer A Urban
- Department of Biology, The Johns Hopkins University, Baltimore, Maryland, USA;
| | - Rajesh Ranjan
- Department of Biology, The Johns Hopkins University, Baltimore, Maryland, USA; .,Howard Hughes Medical Institute, The Johns Hopkins University, Baltimore, Maryland, USA; ,
| | - Xin Chen
- Department of Biology, The Johns Hopkins University, Baltimore, Maryland, USA; .,Howard Hughes Medical Institute, The Johns Hopkins University, Baltimore, Maryland, USA; ,
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10
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Watase GJ, Nelson JO, Yamashita YM. Nonrandom sister chromatid segregation mediates rDNA copy number maintenance in Drosophila. SCIENCE ADVANCES 2022; 8:eabo4443. [PMID: 35895823 PMCID: PMC9328678 DOI: 10.1126/sciadv.abo4443] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Accepted: 06/10/2022] [Indexed: 06/15/2023]
Abstract
Although considered to be exact copies of each other, sister chromatids can segregate nonrandomly in some cases. For example, sister chromatids of the X and Y chromosomes segregate nonrandomly during asymmetric division of male germline stem cells (GSCs) in Drosophila melanogaster. Here, we demonstrate that the ribosomal DNA (rDNA) loci, which are located on the X and Y chromosomes, and an rDNA binding protein Indra are required for nonrandom sister chromatid segregation (NRSS). We provide the evidence that NRSS, following unequal sister chromatid exchange, is a mechanism by which GSCs recover rDNA copy number, counteracting the spontaneous copy number loss that occurs during aging. Our study reveals an unexpected role for NRSS in maintaining germline immortality through maintenance of a vulnerable genomic element, rDNA.
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Affiliation(s)
- George J. Watase
- Whitehead Institute for Biomedical Research, Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
- Howard Hughes Medical Institute, 455 Main Street, Cambridge, MA 02142, USA
| | - Jonathan O. Nelson
- Whitehead Institute for Biomedical Research, Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
- Howard Hughes Medical Institute, 455 Main Street, Cambridge, MA 02142, USA
| | - Yukiko M. Yamashita
- Whitehead Institute for Biomedical Research, Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
- Howard Hughes Medical Institute, 455 Main Street, Cambridge, MA 02142, USA
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11
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Antel M, Raj R, Masoud MYG, Pan Z, Li S, Mellone BG, Inaba M. Interchromosomal interaction of homologous Stat92E alleles regulates transcriptional switch during stem-cell differentiation. Nat Commun 2022; 13:3981. [PMID: 35810185 PMCID: PMC9271046 DOI: 10.1038/s41467-022-31737-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2021] [Accepted: 06/30/2022] [Indexed: 01/24/2023] Open
Abstract
Pairing of homologous chromosomes in somatic cells provides the opportunity of interchromosomal interaction between homologous gene regions. In the Drosophila male germline, the Stat92E gene is highly expressed in a germline stem cell (GSC) and gradually downregulated during the differentiation. Here we show that the pairing of Stat92E is always tight in GSCs and immediately loosened in differentiating daughter cells, gonialblasts (GBs). Disturbance of Stat92E pairing by relocation of one locus to another chromosome or by knockdown of global pairing/anti-pairing factors both result in a failure of Stat92E downregulation, suggesting that the pairing is required for the decline in transcription. Furthermore, the Stat92E enhancer, but not its transcription, is required for the change in pairing state, indicating that pairing is not a consequence of transcriptional changes. Finally, we show that the change in Stat92E pairing is dependent on asymmetric histone inheritance during the asymmetric division of GSCs. Taken together, we propose that the changes in Stat92E pairing status is an intrinsically programmed mechanism for enabling prompt cell fate switch during the differentiation of stem cells. Asymmetric inheritance of organelles, proteins and RNAs occurs during stem cell division. Here the authors show the strength of pairing of homologous Stat92E loci, a stem cell-specific gene, changes immediately after the asymmetric division due to asymmetric inheritance of new histones to one of the daughter cells and is important for turning off gene expression in this cell as it differentiates.
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Affiliation(s)
- Matthew Antel
- Department of Cell Biology, University of Connecticut Health Center, Farmington, CT, USA
| | - Romir Raj
- Department of Cell Biology, University of Connecticut Health Center, Farmington, CT, USA
| | - Madona Y G Masoud
- Department of Cell Biology, University of Connecticut Health Center, Farmington, CT, USA
| | - Ziwei Pan
- The Jackson Laboratory for Genomic Medicine, Farmington, CT, USA.,Department of Genetics and Genomic Sciences, University of Connecticut Health Center, Farmington, CT, USA
| | - Sheng Li
- The Jackson Laboratory for Genomic Medicine, Farmington, CT, USA.,Department of Genetics and Genomic Sciences, University of Connecticut Health Center, Farmington, CT, USA
| | - Barbara G Mellone
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT, USA.,Institute for Systems Genomics, University of Connecticut, Storrs, CT, USA
| | - Mayu Inaba
- Department of Cell Biology, University of Connecticut Health Center, Farmington, CT, USA.
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