1
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Zhu H, Li M, Li M, Li X, Ou G. Cryo-electron tomography elucidates annular intraluminal configurations in Caenorhabditis elegans microtubules. Biol Cell 2024; 116:e2400064. [PMID: 39031999 DOI: 10.1111/boc.202400064] [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: 06/08/2024] [Revised: 06/08/2024] [Accepted: 06/18/2024] [Indexed: 07/22/2024]
Abstract
BACKGROUND INFORMATION Microtubules serve as integral components in cellular operations such as cell division, intracellular trafficking, and cellular architecture. Composed of tubulin protein subunits, these hollow tubular structures have been increasingly elucidated through advanced cryo-electron microscopy (Cryo-EM), which has unveiled the presence of microtubule inner proteins (MIPs) within the microtubular lumen. RESULTS In the present investigation, we employ a synergistic approach incorporating high-pressure freezing, cryo-focused ion beam milling, and Cryo-electron tomography (Cryo-ET) to interrogate the in situ architecture of microtubules in Caenorhabditis elegans larvae. Our Cryo-ET assessments across neuronal cilia and diverse tissue types consistently demonstrate the formation of annular configurations within the microtubular lumen. CONCLUSIONS In concert with recently characterized MIPs, our in situ observations within a living organism corroborate the hypothesis that intricate luminal assemblages exist within microtubule scaffolds. These findings necessitate further exploration into the molecular constituents and functional ramifications of these internal microtubular configurations in both cellular physiology and pathophysiology.
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Affiliation(s)
- Hao Zhu
- Tsinghua-Peking Center for Life Sciences, Beijing Frontier Research Center for Biological Structure, McGovern Institute for Brain Research, School of Life Sciences and MOE Key Laboratory for Protein Science, Tsinghua University, Beijing, China
| | - Ming Li
- Tsinghua-Peking Center for Life Sciences, Beijing Frontier Research Center for Biological Structure, McGovern Institute for Brain Research, School of Life Sciences and MOE Key Laboratory for Protein Science, Tsinghua University, Beijing, China
| | - Meijing Li
- Tsinghua-Peking Center for Life Sciences, Beijing Frontier Research Center for Biological Structure, McGovern Institute for Brain Research, School of Life Sciences and MOE Key Laboratory for Protein Science, Tsinghua University, Beijing, China
| | - Xueming Li
- Tsinghua-Peking Center for Life Sciences, Beijing Frontier Research Center for Biological Structure, McGovern Institute for Brain Research, School of Life Sciences and MOE Key Laboratory for Protein Science, Tsinghua University, Beijing, China
| | - Guangshuo Ou
- Tsinghua-Peking Center for Life Sciences, Beijing Frontier Research Center for Biological Structure, McGovern Institute for Brain Research, School of Life Sciences and MOE Key Laboratory for Protein Science, Tsinghua University, Beijing, China
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2
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Kohlbrenner T, Berger S, Laranjeira AC, Aegerter-Wilmsen T, Comi LF, deMello A, Hajnal A. Actomyosin-mediated apical constriction promotes physiological germ cell death in C. elegans. PLoS Biol 2024; 22:e3002775. [PMID: 39178318 PMCID: PMC11376560 DOI: 10.1371/journal.pbio.3002775] [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: 08/28/2023] [Revised: 09/05/2024] [Accepted: 07/30/2024] [Indexed: 08/25/2024] Open
Abstract
Germ cell apoptosis in Caenorhabditis elegans hermaphrodites is a physiological process eliminating around 60% of all cells in meiotic prophase to maintain tissue homeostasis. In contrast to programmed cell death in the C. elegans soma, the selection of germ cells undergoing apoptosis is stochastic. By live-tracking individual germ cells at the pachytene stage, we found that germ cells smaller than their neighbors are selectively eliminated through apoptosis before differentiating into oocytes. Thus, cell size is a strong predictor of physiological germ cell death. The RAS/MAPK and ECT/RHO/ROCK pathways together regulate germ cell size by controlling actomyosin constriction at the apical rachis bridges, which are cellular openings connecting the syncytial germ cells to a shared cytoplasmic core. Enhancing apical constriction reduces germ cell size and increases the rate of cell death while inhibiting the actomyosin network in the germ cells prevents their death. We propose that actomyosin contractility at the rachis bridges of the syncytial germ cells amplifies intrinsic disparities in cell size. Through this mechanism, the animals can adjust the balance between physiological germ cell death and oocyte differentiation.
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Affiliation(s)
- Tea Kohlbrenner
- Institute of Molecular Life Sciences, University of Zürich, Zürich, Switzerland
- Molecular Life Science PhD Program, University of Zürich and ETH Zürich, Zürich, Switzerland
| | - Simon Berger
- Institute of Molecular Life Sciences, University of Zürich, Zürich, Switzerland
- Institute for Chemical and Bioengineering, ETH Zürich, Zürich, Switzerland
| | - Ana Cristina Laranjeira
- Institute of Molecular Life Sciences, University of Zürich, Zürich, Switzerland
- Molecular Life Science PhD Program, University of Zürich and ETH Zürich, Zürich, Switzerland
| | | | - Laura Filomena Comi
- Institute of Molecular Life Sciences, University of Zürich, Zürich, Switzerland
- Molecular Life Science PhD Program, University of Zürich and ETH Zürich, Zürich, Switzerland
| | - Andrew deMello
- Institute for Chemical and Bioengineering, ETH Zürich, Zürich, Switzerland
| | - Alex Hajnal
- Institute of Molecular Life Sciences, University of Zürich, Zürich, Switzerland
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3
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Xie Z, Chai Y, Zhu Z, Shen Z, Guo Z, Zhao Z, Xiao L, Du Z, Ou G, Li W. Vacuolar H +-ATPase determines daughter cell fates through asymmetric segregation of the nucleosome remodeling and deacetylase complex. eLife 2024; 12:RP89032. [PMID: 38994733 PMCID: PMC11245309 DOI: 10.7554/elife.89032] [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: 07/13/2024] Open
Abstract
Asymmetric cell divisions (ACDs) generate two daughter cells with identical genetic information but distinct cell fates through epigenetic mechanisms. However, the process of partitioning different epigenetic information into daughter cells remains unclear. Here, we demonstrate that the nucleosome remodeling and deacetylase (NuRD) complex is asymmetrically segregated into the surviving daughter cell rather than the apoptotic one during ACDs in Caenorhabditis elegans. The absence of NuRD triggers apoptosis via the EGL-1-CED-9-CED-4-CED-3 pathway, while an ectopic gain of NuRD enables apoptotic daughter cells to survive. We identify the vacuolar H+-adenosine triphosphatase (V-ATPase) complex as a crucial regulator of NuRD's asymmetric segregation. V-ATPase interacts with NuRD and is asymmetrically segregated into the surviving daughter cell. Inhibition of V-ATPase disrupts cytosolic pH asymmetry and NuRD asymmetry. We suggest that asymmetric segregation of V-ATPase may cause distinct acidification levels in the two daughter cells, enabling asymmetric epigenetic inheritance that specifies their respective life-versus-death fates.
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Affiliation(s)
- Zhongyun Xie
- Tsinghua-Peking Center for Life Sciences, Beijing Frontier Research Center for Biological Structure, McGovern Institute for Brain Research, State Key Laboratory of Membrane Biology, School of Life Sciences and MOE Key Laboratory for Protein Science, Tsinghua UniversityBeijingChina
| | - Yongping Chai
- Tsinghua-Peking Center for Life Sciences, Beijing Frontier Research Center for Biological Structure, McGovern Institute for Brain Research, State Key Laboratory of Membrane Biology, School of Life Sciences and MOE Key Laboratory for Protein Science, Tsinghua UniversityBeijingChina
| | - Zhiwen Zhu
- Tsinghua-Peking Center for Life Sciences, Beijing Frontier Research Center for Biological Structure, McGovern Institute for Brain Research, State Key Laboratory of Membrane Biology, School of Life Sciences and MOE Key Laboratory for Protein Science, Tsinghua UniversityBeijingChina
| | - Zijie Shen
- Tsinghua-Peking Center for Life Sciences, Beijing Frontier Research Center for Biological Structure, McGovern Institute for Brain Research, State Key Laboratory of Membrane Biology, School of Life Sciences and MOE Key Laboratory for Protein Science, Tsinghua UniversityBeijingChina
| | - Zhengyang Guo
- Tsinghua-Peking Center for Life Sciences, Beijing Frontier Research Center for Biological Structure, McGovern Institute for Brain Research, State Key Laboratory of Membrane Biology, School of Life Sciences and MOE Key Laboratory for Protein Science, Tsinghua UniversityBeijingChina
| | - Zhiguang Zhao
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, University of Chinese Academy of SciencesBeijingChina
| | - Long Xiao
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, University of Chinese Academy of SciencesBeijingChina
| | - Zhuo Du
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, University of Chinese Academy of SciencesBeijingChina
| | - Guangshuo Ou
- Tsinghua-Peking Center for Life Sciences, Beijing Frontier Research Center for Biological Structure, McGovern Institute for Brain Research, State Key Laboratory of Membrane Biology, School of Life Sciences and MOE Key Laboratory for Protein Science, Tsinghua UniversityBeijingChina
| | - Wei Li
- School of Medicine, Tsinghua UniversityBeijingChina
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4
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Robinson J, Teuliere J, Yoo S, Garriga G. NMY-2, TOE-2 and PIG-1 regulate Caenorhabditis elegans asymmetric cell divisions. PLoS One 2024; 19:e0304064. [PMID: 38787850 PMCID: PMC11125515 DOI: 10.1371/journal.pone.0304064] [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: 09/01/2023] [Accepted: 05/06/2024] [Indexed: 05/26/2024] Open
Abstract
Asymmetric cell division is an important mechanism that generates cellular diversity during development. Not only do asymmetric cell divisions produce daughter cells of different fates, but many can also produce daughters of different sizes, which we refer to as Daughter Cell Size Asymmetry (DCSA). In Caenorhabditis elegans, apoptotic cells are frequently produced by asymmetric divisions that exhibit DCSA, where the smaller daughter dies. We focus here on the divisions of the Q.a and Q.p neuroblasts, which produce larger surviving cells and smaller apoptotic cells and divide with opposite polarity using both distinct and overlapping mechanisms. Several proteins regulate DCSA in these divisions. Previous studies showed that the PIG-1/MELK and TOE-2 proteins regulate DCSA in both the Q.a and Q.p divisions, and the non-muscle myosin NMY-2 regulates DCSA in the Q.a division but not the Q.p division. In this study, we examined endogenously tagged NMY-2, TOE-2, and PIG-1 reporters and characterized their distribution at the cortex during the Q.a and Q.p divisions. In both divisions, TOE-2 localized toward the side of the dividing cell that produced the smaller daughter, whereas PIG-1 localized toward the side that produced the larger daughter. As previously reported, NMY-2 localized to the side of Q.a that produced the smaller daughter and did not localize asymmetrically in Q.p. We used temperature-sensitive nmy-2 mutants to determine the role of nmy-2 in these divisions and were surprised to find that these mutants only displayed DCSA defects in the Q.p division. We generated double mutant combinations between the nmy-2 mutations and mutations in toe-2 and pig-1. Because previous studies indicate that DCSA defects result in the transformation of cells fated to die into their sister cells, the finding that the nmy-2 mutations did not significantly alter the Q.a and Q.p DCSA defects of toe-2 and pig-1 mutants but did alter the number of daughter cells produced by Q.a and Q.p suggests that nmy-2 plays a role in specifying the fates of the Q.a and Q.p that is independent of its role in DCSA.
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Affiliation(s)
- Joseph Robinson
- Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, CA, United States of America
| | - Jerome Teuliere
- Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, CA, United States of America
| | - Shinja Yoo
- Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, CA, United States of America
| | - Gian Garriga
- Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, CA, United States of America
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5
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Bermudez A, Latham ZD, Ma AJ, Bi D, Hu JK, Lin NYC. Regulation of Chromatin Modifications through Coordination of Nucleus Size and Epithelial Cell Morphology Heterogeneity. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.18.590164. [PMID: 38712099 PMCID: PMC11071433 DOI: 10.1101/2024.04.18.590164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
Cell morphology heterogeneity within epithelial collectives is a pervasive phenomenon intertwined with tissue mechanical properties. Despite its widespread occurrence, the underlying mechanisms driving cell morphology heterogeneity and its consequential biological ramifications remain elusive. Here, we investigate the dynamic evolution of epithelial cell morphology and nucleus morphology during crowding, unveiling a consistent correlation between the two. Our investigation reveals a persistent log-normal probability distribution characterizing both cell and nucleus areas across diverse crowding stages and epithelial model systems. We showed that this morphological diversity arises from asymmetric partitioning during cell division and is perpetuated through actomyosin-mediated regulation of cell-nucleus size coordination. Moreover, we provide insights into the impact of nucleus morphology on chromatin dynamics, demonstrating that constraining nucleus area leads to downregulation of the euchromatic mark H3K9ac and upregulation of the heterochromatic mark H3K27me3 through modulation of histone demethylase UTX expression. These findings under-score the significance of cell morphology heterogeneity as a driver of chromatin state diversity, shaping functional variability within epithelial tissues.
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6
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Mullan TW, Felton T, Tam J, Kasem O, Yeung TJ, Memar N, Schnabel R, Poole RJ. Control of successive unequal cell divisions by neural cell fate regulators determines embryonic neuroblast cell size. Development 2024; 151:dev200981. [PMID: 38205939 PMCID: PMC10911278 DOI: 10.1242/dev.200981] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Accepted: 01/02/2024] [Indexed: 01/12/2024]
Abstract
Asymmetric cell divisions often generate daughter cells of unequal size in addition to different fates. In some contexts, daughter cell size asymmetry is thought to be a key input to specific binary cell fate decisions. An alternative possibility is that unequal division is a mechanism by which a variety of cells of different sizes are generated during embryonic development. We show here that two unequal cell divisions precede neuroblast formation in the C lineage of Caenorhabditis elegans. The equalisation of these divisions in a pig-1/MELK mutant background has little effect on neuroblast specification. Instead, we demonstrate that let-19/MDT13 is a regulator of the proneural basic helix-loop-helix transcription factor hlh-14/ASCL1 and find that both are required to concomitantly regulate the acquisition of neuroblast identity and neuroblast cell size. Thus, embryonic neuroblast cell size in this lineage is progressively regulated in parallel with identity by key neural cell fate regulators. We propose that key cell fate determinants have a previously unappreciated function in regulating unequal cleavage, and therefore cell size, of the progenitor cells whose daughter cell fates they then go on to specify.
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Affiliation(s)
- Thomas W. Mullan
- Department of Cell and Developmental Biology, University College London, London WC1E 6BT, UK
| | - Terry Felton
- Department of Cell and Developmental Biology, University College London, London WC1E 6BT, UK
| | - Janis Tam
- Department of Cell and Developmental Biology, University College London, London WC1E 6BT, UK
| | - Osama Kasem
- Department of Cell and Developmental Biology, University College London, London WC1E 6BT, UK
| | - Tim J. Yeung
- Department of Cell and Developmental Biology, University College London, London WC1E 6BT, UK
| | - Nadin Memar
- Department of Cell and Developmental Biology, University College London, London WC1E 6BT, UK
- Institut für Genetik, TU Braunschweig, D-38106 Braunschweig, Germany
| | - Ralf Schnabel
- Institut für Genetik, TU Braunschweig, D-38106 Braunschweig, Germany
| | - Richard J. Poole
- Department of Cell and Developmental Biology, University College London, London WC1E 6BT, UK
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7
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Zhu F, Lu X, Jiang Y, Wang D, Pan L, Jia C, Zhang L, Xie Y, Zhao M, Liu H, Wang M, Wang T, Liu H, Li J. Proteomics reveals the underlying mechanism by which the first uneven division affects embryonic development in pig. Theriogenology 2023; 210:42-52. [PMID: 37473595 DOI: 10.1016/j.theriogenology.2023.07.017] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Revised: 07/13/2023] [Accepted: 07/14/2023] [Indexed: 07/22/2023]
Abstract
One of the most typical abnormal cleavage patterns during early embryonic development is uneven division, but the first uneven division of pig zygote is common. Uneven division results in different daughter cell sizes and an uneven distribution of organelles such as lipid droplet, mitochondria, but the developmental capacity of daughter cells and proteomic changes of daughter cells are still unclear. Therefore, the developmental ability and proteomic quantification were investigated on blastomeres from even division (ED) or uneven division (UD) embryos at 2-cell stage in the present study. Firstly, the developmental ability was affected by the blastomeric size, when compared with medium blastomeres (MBs), the large blastomeres (LBs) with the higher cleavage rate but the small blastomeres (SBs) with the lower rate was observed. Subsequently, proteomic analysis was performed on blastomeres of LBs, MBs and SBs, a total of 109 DEPs were detected, which were involved in protein metabolism and processing, energy metabolism and ribosome. In particular, DEPs in LBs vs. SBs were focused on RNA binding and actin cytoskeletal tissue. Two protein-dense networks associated with RNA binding and cytoskeleton were revealed by further protein-protein interaction (PPI) analysis of DEPs in LBs vs. SBs, that DDX1 related to RNA binding and ACTB related to cytoskeleton were confirmed in UD embryos. Therefore, a briefly information of DEPs in blastomeres of 2-cell stage pig embryos was described in the present study, and it further confirmed that the formation of uneven division of the first cell cycle of pig embryos might be controlled by the cytoskeleton; the developmental capacity of daughter cells might be affected by the energy metabolism, RNA binding and ribosome, and further account for the developmental potential of the whole embryo.
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Affiliation(s)
- Fuquan Zhu
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, 210018, China
| | - Xinyue Lu
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, 210018, China
| | - Yuan Jiang
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, 210018, China
| | - Dayu Wang
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, 210018, China
| | - Linqing Pan
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, 210018, China
| | - Chao Jia
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, 210018, China
| | - Lin Zhang
- Jiangsu Yangyu Ecological Agriculture Co., Ltd, Taixing, 225400, China
| | - Yan Xie
- Taixing Animal Husbandry and Veterinary Center, Taixing, 225400, China
| | - Mingyue Zhao
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, 210018, China
| | - Huijun Liu
- Key Laboratory of Microbial Technology and Bioinformatics of Zhejiang Province, Zhejiang Institute of Microbiology, Hangzhou, 310012, China
| | - Meixia Wang
- Key Laboratory of Microbial Technology and Bioinformatics of Zhejiang Province, Zhejiang Institute of Microbiology, Hangzhou, 310012, China
| | - Tingzhang Wang
- Key Laboratory of Microbial Technology and Bioinformatics of Zhejiang Province, Zhejiang Institute of Microbiology, Hangzhou, 310012, China
| | - Honglin Liu
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, 210018, China
| | - Juan Li
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, 210018, China.
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8
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Zhao Q, Rangan R, Weng S, Özdemir C, Sarinay Cenik E. Inhibition of ribosome biogenesis in the epidermis is sufficient to trigger organism-wide growth quiescence independently of nutritional status in C. elegans. PLoS Biol 2023; 21:e3002276. [PMID: 37651423 PMCID: PMC10499265 DOI: 10.1371/journal.pbio.3002276] [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: 10/05/2022] [Revised: 09/13/2023] [Accepted: 07/26/2023] [Indexed: 09/02/2023] Open
Abstract
Interorgan communication is crucial for multicellular organismal growth, development, and homeostasis. Cell nonautonomous inhibitory cues, which limit tissue-specific growth alterations, are not well characterized due to cell ablation approach limitations. In this study, we employed the auxin-inducible degradation system in C. elegans to temporally and spatially modulate ribosome biogenesis, through depletion of essential factors (RPOA-2, GRWD-1, or TSR-2). Our findings reveal that embryo-wide inhibition of ribosome biogenesis induces a reversible early larval growth quiescence, distinguished by a unique gene expression signature that is different from starvation or dauer stages. When ribosome biogenesis is inhibited in volumetrically similar tissues, including body wall muscle, epidermis, pharynx, intestine, or germ line, it results in proportionally stunted growth across the organism to different degrees. We show that specifically inhibiting ribosome biogenesis in the epidermis is sufficient to trigger an organism-wide growth quiescence. Epidermis-specific ribosome depletion leads to larval growth quiescence at the L3 stage, reduces organism-wide protein synthesis, and induced cell nonautonomous gene expression alterations. Further molecular analysis reveals overexpression of secreted proteins, suggesting an organism-wide regulatory mechanism. We find that UNC-31, a dense-core vesicle (DCV) pathway component, plays a significant role in epidermal ribosome biogenesis-mediated growth quiescence. Our tissue-specific knockdown experiments reveal that the organism-wide growth quiescence induced by epidermal-specific ribosome biogenesis inhibition is suppressed by reducing unc-31 expression in the epidermis, but not in neurons or body wall muscles. Similarly, IDA-1, a membrane-associated protein of the DCV, is overexpressed, and its knockdown in epidermis suppresses the organism-wide growth quiescence in response to epidermal ribosome biogenesis inhibition. Finally, we observe an overall increase in DCV puncta labeled by IDA-1 when epidermal ribosome biogenesis is inhibited, and these puncta are present in or near epidermal cells. In conclusion, these findings suggest a novel mechanism of nutrition-independent multicellular growth coordination initiated from the epidermis tissue upon ribosome biogenesis inhibition.
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Affiliation(s)
- Qiuxia Zhao
- Department of Molecular Biosciences, University of Texas at Austin, Austin, Texas, United States of America
| | - Rekha Rangan
- Department of Molecular Biosciences, University of Texas at Austin, Austin, Texas, United States of America
| | - Shinuo Weng
- Department of Molecular Biosciences, University of Texas at Austin, Austin, Texas, United States of America
| | - Cem Özdemir
- Department of Molecular Biosciences, University of Texas at Austin, Austin, Texas, United States of America
| | - Elif Sarinay Cenik
- Department of Molecular Biosciences, University of Texas at Austin, Austin, Texas, United States of America
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9
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Montembault E, Deduyer I, Claverie MC, Bouit L, Tourasse NJ, Dupuy D, McCusker D, Royou A. Two RhoGEF isoforms with distinct localisation control furrow position during asymmetric cell division. Nat Commun 2023; 14:3209. [PMID: 37268622 DOI: 10.1038/s41467-023-38912-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Accepted: 05/19/2023] [Indexed: 06/04/2023] Open
Abstract
Cytokinesis partitions cellular content between daughter cells. It relies on the formation of an acto-myosin contractile ring, whose constriction induces the ingression of the cleavage furrow between the segregated chromatids. Rho1 GTPase and its RhoGEF (Pbl) are essential for this process. However, how Rho1 is regulated to sustain furrow ingression while maintaining correct furrow position remains poorly defined. Here, we show that during asymmetric division of Drosophila neuroblasts, Rho1 is controlled by two Pbl isoforms with distinct localisation. Spindle midzone- and furrow-enriched Pbl-A focuses Rho1 at the furrow to sustain efficient ingression, while Pbl-B pan-plasma membrane localization promotes the broadening of Rho1 activity and the subsequent enrichment of myosin on the entire cortex. This enlarged zone of Rho1 activity is critical to adjust furrow position, thereby preserving correct daughter cell size asymmetry. Our work highlights how the use of isoforms with distinct localisation makes an essential process more robust.
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Affiliation(s)
- Emilie Montembault
- CNRS, UMR5095, University of Bordeaux, Institut Européen de Chimie et Biologie, 2 rue Robert Escarpit, 33607, Pessac, France
- CNRS, UMR5095, University of Bordeaux, Institut de Biologie et Génétique Cellulaire, 1 rue Camille Saint-Saëns, 33077, Bordeaux, France
| | - Irène Deduyer
- CNRS, UMR5095, University of Bordeaux, Institut Européen de Chimie et Biologie, 2 rue Robert Escarpit, 33607, Pessac, France
- CNRS, UMR5095, University of Bordeaux, Institut de Biologie et Génétique Cellulaire, 1 rue Camille Saint-Saëns, 33077, Bordeaux, France
| | - Marie-Charlotte Claverie
- CNRS, UMR5095, University of Bordeaux, Institut Européen de Chimie et Biologie, 2 rue Robert Escarpit, 33607, Pessac, France
- CNRS, UMR5095, University of Bordeaux, Institut de Biologie et Génétique Cellulaire, 1 rue Camille Saint-Saëns, 33077, Bordeaux, France
| | - Lou Bouit
- CNRS, UMR5095, University of Bordeaux, Institut Européen de Chimie et Biologie, 2 rue Robert Escarpit, 33607, Pessac, France
- CNRS, UMR5297, University of Bordeaux, 146 Rue Léo Saignat, 33076, Bordeaux, France
| | - Nicolas J Tourasse
- University of Bordeaux, INSERM, U1212, Institut Européen de Chimie et Biologie, 2 rue Robert Escarpit, 33607, Pessac, France
| | - Denis Dupuy
- University of Bordeaux, INSERM, U1212, Institut Européen de Chimie et Biologie, 2 rue Robert Escarpit, 33607, Pessac, France
| | - Derek McCusker
- CNRS, UMR5095, University of Bordeaux, Institut Européen de Chimie et Biologie, 2 rue Robert Escarpit, 33607, Pessac, France
- CNRS, UMR5095, University of Bordeaux, Institut de Biologie et Génétique Cellulaire, 1 rue Camille Saint-Saëns, 33077, Bordeaux, France
| | - Anne Royou
- CNRS, UMR5095, University of Bordeaux, Institut Européen de Chimie et Biologie, 2 rue Robert Escarpit, 33607, Pessac, France.
- CNRS, UMR5095, University of Bordeaux, Institut de Biologie et Génétique Cellulaire, 1 rue Camille Saint-Saëns, 33077, Bordeaux, France.
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10
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Daeden A, Mietke A, Derivery E, Seum C, Jülicher F, Gonzalez-Gaitan M. Polarized branched Actin modulates cortical mechanics to produce unequal-size daughters during asymmetric division. Nat Cell Biol 2023; 25:235-245. [PMID: 36747081 PMCID: PMC9928585 DOI: 10.1038/s41556-022-01058-9] [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: 08/03/2021] [Accepted: 11/22/2022] [Indexed: 02/08/2023]
Abstract
The control of cell shape during cytokinesis requires a precise regulation of mechanical properties of the cell cortex. Only few studies have addressed the mechanisms underlying the robust production of unequal-sized daughters during asymmetric cell division. Here we report that unequal daughter-cell sizes resulting from asymmetric sensory organ precursor divisions in Drosophila are controlled by the relative amount of cortical branched Actin between the two cell poles. We demonstrate this by mistargeting the machinery for branched Actin dynamics using nanobodies and optogenetics. We can thereby engineer the cell shape with temporal precision and thus the daughter-cell size at different stages of cytokinesis. Most strikingly, inverting cortical Actin asymmetry causes an inversion of daughter-cell sizes. Our findings uncover the physical mechanism by which the sensory organ precursor mother cell controls relative daughter-cell size: polarized cortical Actin modulates the cortical bending rigidity to set the cell surface curvature, stabilize the division and ultimately lead to unequal daughter-cell size.
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Affiliation(s)
- Alicia Daeden
- Department of Biochemistry, Faculty of Sciences, University of Geneva, Geneva, Switzerland
| | - Alexander Mietke
- Department of Mathematics, Massachusetts Institute of Technology, Cambridge, MA, USA
- Max Planck Institute for the Physics of Complex Systems, Dresden, Germany
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
- Center for Systems Biology Dresden, Dresden, Germany
| | - Emmanuel Derivery
- Department of Biochemistry, Faculty of Sciences, University of Geneva, Geneva, Switzerland
- MRC Laboratory of Molecular Biology, Cambridge, UK
| | - Carole Seum
- Department of Biochemistry, Faculty of Sciences, University of Geneva, Geneva, Switzerland
| | - Frank Jülicher
- Max Planck Institute for the Physics of Complex Systems, Dresden, Germany
| | - Marcos Gonzalez-Gaitan
- Department of Biochemistry, Faculty of Sciences, University of Geneva, Geneva, Switzerland.
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11
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Shah P, Bao Z, Zaidel-Bar R. Visualizing and quantifying molecular and cellular processes in C. elegans using light microscopy. Genetics 2022; 221:6619563. [PMID: 35766819 DOI: 10.1093/genetics/iyac068] [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: 12/11/2021] [Accepted: 04/14/2022] [Indexed: 11/14/2022] Open
Abstract
Light microscopes are the cell and developmental biologists' "best friend", providing a means to see structures and follow dynamics from the protein to the organism level. A huge advantage of C. elegans as a model organism is its transparency, which coupled with its small size means that nearly every biological process can be observed and measured with the appropriate probe and light microscope. Continuous improvement in microscope technologies along with novel genome editing techniques to create transgenic probes have facilitated the development and implementation of a dizzying array of methods for imaging worm embryos, larvae and adults. In this review we provide an overview of the molecular and cellular processes that can be visualized in living worms using light microscopy. A partial inventory of fluorescent probes and techniques successfully used in worms to image the dynamics of cells, organelles, DNA, and protein localization and activity is followed by a practical guide to choosing between various imaging modalities, including widefield, confocal, lightsheet, and structured illumination microscopy. Finally, we discuss the available tools and approaches, including machine learning, for quantitative image analysis tasks, such as colocalization, segmentation, object tracking, and lineage tracing. Hopefully, this review will inspire worm researchers who have not yet imaged their worms to begin, and push those who are imaging to go faster, finer, and longer.
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Affiliation(s)
- Pavak Shah
- Department of Molecular, Cell, and Developmental Biology, University of California Los Angeles, Los Angeles 90095, USA
| | - Zhirong Bao
- Developmental Biology Program, Sloan Kettering Institute, New York, New York 10065, USA
| | - Ronen Zaidel-Bar
- Department of Cell and Developmental Biology, Faculty of Medicine, Tel Aviv University, Tel Aviv 6997801, Israel
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12
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Li T, Wang X, Feng Z, Zou Y. Live imaging of postembryonic developmental processes in C. elegans. STAR Protoc 2022; 3:101336. [PMID: 35496803 PMCID: PMC9043753 DOI: 10.1016/j.xpro.2022.101336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Live imaging is an important tool to track dynamic processes such as neuronal patterning events. Here, we describe a protocol for time-lapse microscopy analysis using neuronal migration and dendritic growth as examples. This protocol can provide detailed information for understanding cellular dynamics during postembryonic development in Caenorhabditis elegans (C. elegans). For complete details on the use and execution of this protocol, please refer to Feng et al. (2020), Li et al. (2021), and Wang et al. (2021).
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Affiliation(s)
- Tingting Li
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
- Institute of Neuroscience, State Key Laboratory of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xinjian Wang
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Zhigang Feng
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Yan Zou
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
- Institute of Neuroscience, State Key Laboratory of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
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13
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Wnt signaling polarizes cortical actin polymerization to increase daughter cell asymmetry. Cell Discov 2022; 8:22. [PMID: 35228529 PMCID: PMC8885824 DOI: 10.1038/s41421-022-00376-4] [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: 10/06/2021] [Accepted: 01/06/2022] [Indexed: 01/02/2023] Open
Abstract
Asymmetric positioning of the mitotic spindle contributes to the generation of two daughter cells with distinct sizes and fates. Here, we investigated an asymmetric division in the Caenorhabditis elegans Q neuroblast lineage. In this division, beginning with an asymmetrically positioned spindle, the daughter-cell size differences continuously increased during cytokinesis, and the smaller daughter cell in the posterior eventually underwent apoptosis. We found that Arp2/3-dependent F-actin assembled in the anterior but not posterior cortex during division, suggesting that asymmetric expansion forces generated by actin polymerization may enlarge the anterior daughter cell. Consistent with this, inhibition of cortical actin polymerization or artificially equalizing actin assembly led to symmetric cell division. Furthermore, disruption of the Wnt gradient or its downstream components impaired asymmetric cortical actin assembly and caused symmetric division. Our results show that Wnt signaling establishes daughter cell asymmetry by polarizing cortical actin polymerization in a dividing cell.
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14
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Deng Q, Wang H. Re-visiting the principles of apicobasal polarity in Drosophila neural stem cells. Dev Biol 2022; 484:57-62. [PMID: 35181298 DOI: 10.1016/j.ydbio.2022.02.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Revised: 01/19/2022] [Accepted: 02/13/2022] [Indexed: 11/18/2022]
Abstract
The ability of stem cells to divide asymmetrically is crucial for cell-type diversity and tissue homeostasis. Drosophila neural stem cells, also knowns as neuroblasts, utilize asymmetric cell division to self-renew and give rise to differentiated daughter cells. Drosophila neuroblasts relies on the polarized protein complexes on the apical and basal cortex to govern cell polarity and asymmetry. Here, we review recent advances in our understanding of the neuroblast polarity focusing on how actin cytoskeleton, phosphoinositide lipids and liquid-liquid phase separation regulate the asymmetric cell division of Drosophila neuroblasts.
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Affiliation(s)
- Qiannan Deng
- Neuroscience & Behavioral Disorders Programme, Duke-NUS Medical School, 8 College Road, 169857, Singapore
| | - Hongyan Wang
- Neuroscience & Behavioral Disorders Programme, Duke-NUS Medical School, 8 College Road, 169857, Singapore; Dept. of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, 117597, Singapore; Integrative Sciences and Engineering Programme, National University of Singapore, 28 Medical Drive, 117456, Singapore.
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15
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Sugioka K. Symmetry-breaking of animal cytokinesis. Semin Cell Dev Biol 2021; 127:100-109. [PMID: 34955355 DOI: 10.1016/j.semcdb.2021.12.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 12/05/2021] [Accepted: 12/16/2021] [Indexed: 12/24/2022]
Abstract
Cytokinesis is a mechanism that separates dividing cells via constriction of a supramolecular structure, the contractile ring. In animal cells, three modes of symmetry-breaking of cytokinesis result in unilateral cytokinesis, asymmetric cell division, and oriented cell division. Each mode of cytokinesis plays a significant role in tissue patterning and morphogenesis by the mechanisms that control the orientation and position of the contractile ring relative to the body axis. Despite its significance, the mechanisms involved in the symmetry-breaking of cytokinesis remain unclear in many cell types. Classical embryologists have identified that the geometric relationship between the mitotic spindle and cell cortex induces cytokinesis asymmetry; however, emerging evidence suggests that a concerted flow of compressional cell-cortex materials (cortical flow) is a spindle-independent driving force in spatial cytokinesis control. This review provides an overview of both classical and emerging mechanisms of cytokinesis asymmetry and their roles in animal development.
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Affiliation(s)
- Kenji Sugioka
- Life Sciences Institute, The University of British Columbia, Vancouver, BC V6T1Z3, Canada; Department of Zoology, The University of British Columbia, Vancouver, BC V6T1Z3, Canada.
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16
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Godard BG, Dumollard R, Heisenberg CP, McDougall A. Combined effect of cell geometry and polarity domains determines the orientation of unequal division. eLife 2021; 10:75639. [PMID: 34889186 PMCID: PMC8691831 DOI: 10.7554/elife.75639] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Accepted: 12/02/2021] [Indexed: 11/13/2022] Open
Abstract
Cell division orientation is thought to result from a competition between cell geometry and polarity domains controlling the position of the mitotic spindle during mitosis. Depending on the level of cell shape anisotropy or the strength of the polarity domain, one dominates the other and determines the orientation of the spindle. Whether and how such competition is also at work to determine unequal cell division (UCD), producing daughter cells of different size, remains unclear. Here, we show that cell geometry and polarity domains cooperate, rather than compete, in positioning the cleavage plane during UCDs in early ascidian embryos. We found that the UCDs and their orientation at the ascidian third cleavage rely on the spindle tilting in an anisotropic cell shape, and cortical polarity domains exerting different effects on spindle astral microtubules. By systematically varying mitotic cell shape, we could modulate the effect of attractive and repulsive polarity domains and consequently generate predicted daughter cell size asymmetries and position. We therefore propose that the spindle position during UCD is set by the combined activities of cell geometry and polarity domains, where cell geometry modulates the effect of cortical polarity domain(s).
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Affiliation(s)
- Benoit G Godard
- Laboratoire de Biologie du Développement de Villefranche-sur-mer, Institut de la Mer de Villefranche-sur-mer, Sorbonne Université, CNRS, Villefranche sur Mer, France.,Institute of Science and Technology Austria, Klosterneuburg, Austria
| | - Remi Dumollard
- Laboratoire de Biologie du Développement de Villefranche-sur-mer, Institut de la Mer de Villefranche-sur-mer, Sorbonne Université, CNRS, Villefranche sur Mer, France
| | | | - Alex McDougall
- Laboratoire de Biologie du Développement de Villefranche-sur-mer, Institut de la Mer de Villefranche-sur-mer, Sorbonne Université, CNRS, Villefranche sur Mer, France
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17
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Biglou SG, Bendena WG, Chin-Sang I. An overview of the insulin signaling pathway in model organisms Drosophila melanogaster and Caenorhabditis elegans. Peptides 2021; 145:170640. [PMID: 34450203 DOI: 10.1016/j.peptides.2021.170640] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Revised: 08/01/2021] [Accepted: 08/20/2021] [Indexed: 12/12/2022]
Abstract
The insulin/insulin-like growth factor signaling pathway is an evolutionary conserved pathway across metazoans and is required for development, metabolism and behavior. This pathway is associated with various human metabolic disorders and cancers. Thus, model organisms including Drosophila melanogaster and Caenorhabditis elegans provide excellent opportunities to examine the structure and function of this pathway and its influence on cellular metabolism and proliferation. In this review, we will provide an overview of human insulin and the human insulin signaling pathway and explore the recent discoveries in model organisms Drosophila melanogaster and Caenorhabditis elegans. Our review will provide information regarding the various insulin-like peptides in model organisms as well as the conserved functions of insulin signaling pathways. Further investigation of the insulin signaling pathway in model organisms could provide a promising opportunity to develop novel therapies for various metabolic disorders and insulin-mediated cancers.
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Affiliation(s)
- Sanaz G Biglou
- Department of Biology, Queen's University Kingston, ON, K7L3N6, Canada
| | - William G Bendena
- Department of Biology, Queen's University Kingston, ON, K7L3N6, Canada; Centre for Neuroscience, Queen's University, Kingston, ON, K7L3N6, Canada.
| | - Ian Chin-Sang
- Department of Biology, Queen's University Kingston, ON, K7L3N6, Canada
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18
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Wang X, Li L, Shao Y, Wei J, Song R, Zheng S, Li Y, Song F. Effects of the Laplace pressure on the cells during cytokinesis. iScience 2021; 24:102945. [PMID: 34458697 PMCID: PMC8377492 DOI: 10.1016/j.isci.2021.102945] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 04/28/2021] [Accepted: 07/29/2021] [Indexed: 11/29/2022] Open
Abstract
The Laplace pressure is one of the most fundamental regulators that determine cell shape and function, and thus has been receiving widespread attention. Here, we systemically investigate the effect of the Laplace pressure on the shape and function of the cells during cytokinesis. We find that the Laplace pressure during cytokinesis can directly control the distribution and size of cell blebbing and adjust the symmetry of cell division by virtue of changing the characteristics of cell blebbing. Further, we demonstrate that the Laplace pressure changes the structural uniformity of cell boundary to regulate the symmetry of cell division. Our findings provide further insights as to the important role of the Laplace pressure in regulating the symmetry of cell division during cytokinesis.
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Affiliation(s)
- Xiaohuan Wang
- State Key Laboratory of Nonlinear Mechanics and Beijing Key Laboratory of Engineered Construction and Mechanobiology, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, China
- School of Engineering Science, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Long Li
- State Key Laboratory of Nonlinear Mechanics and Beijing Key Laboratory of Engineered Construction and Mechanobiology, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, China
| | - Yingfeng Shao
- State Key Laboratory of Nonlinear Mechanics and Beijing Key Laboratory of Engineered Construction and Mechanobiology, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, China
| | - Jiachen Wei
- State Key Laboratory of Nonlinear Mechanics and Beijing Key Laboratory of Engineered Construction and Mechanobiology, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, China
| | - Ruopu Song
- School of Life Science and Health, Northeastern University, Shenyang 110169, China
| | - Songjie Zheng
- State Key Laboratory of Nonlinear Mechanics and Beijing Key Laboratory of Engineered Construction and Mechanobiology, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, China
- School of Engineering Science, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yuqiao Li
- State Key Laboratory of Nonlinear Mechanics and Beijing Key Laboratory of Engineered Construction and Mechanobiology, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, China
- School of Engineering Science, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Fan Song
- State Key Laboratory of Nonlinear Mechanics and Beijing Key Laboratory of Engineered Construction and Mechanobiology, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, China
- School of Engineering Science, University of Chinese Academy of Sciences, Beijing 100049, China
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19
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Phase Separation and Mechanical Forces in Regulating Asymmetric Cell Division of Neural Stem Cells. Int J Mol Sci 2021; 22:ijms221910267. [PMID: 34638607 PMCID: PMC8508713 DOI: 10.3390/ijms221910267] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 09/20/2021] [Accepted: 09/21/2021] [Indexed: 12/13/2022] Open
Abstract
Asymmetric cell division (ACD) of neural stem cells and progenitors not only renews the stem cell population but also ensures the normal development of the nervous system, producing various types of neurons with different shapes and functions in the brain. One major mechanism to achieve ACD is the asymmetric localization and uneven segregation of intracellular proteins and organelles into sibling cells. Recent studies have demonstrated that liquid-liquid phase separation (LLPS) provides a potential mechanism for the formation of membrane-less biomolecular condensates that are asymmetrically distributed on limited membrane regions. Moreover, mechanical forces have emerged as pivotal regulators of asymmetric neural stem cell division by generating sibling cell size asymmetry. In this review, we will summarize recent discoveries of ACD mechanisms driven by LLPS and mechanical forces.
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20
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Actin filament debranching regulates cell polarity during cell migration and asymmetric cell division. Proc Natl Acad Sci U S A 2021; 118:2100805118. [PMID: 34507987 DOI: 10.1073/pnas.2100805118] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/07/2021] [Indexed: 01/10/2023] Open
Abstract
The formation of the branched actin networks is essential for cell polarity, but it remains unclear how the debranching activity of actin filaments contributes to this process. Here, we showed that an evolutionarily conserved coronin family protein, the Caenorhabditis elegans POD-1, debranched the Arp2/3-nucleated actin filaments in vitro. By fluorescence live imaging analysis of the endogenous POD-1 protein, we found that POD-1 colocalized with Arp2/3 at the leading edge of the migrating C. elegans neuroblasts. Conditional mutations of POD-1 in neuroblasts caused aberrant actin assembly, disrupted cell polarity, and impaired cell migration. In C. elegans one-cell-stage embryos, POD-1 and Arp2/3, moved together during cell polarity establishment, and inhibition of POD-1 blocked Arp2/3 motility and affected the polarized cortical flow, leading to symmetric segregation of cell fate determinants. Together, these results indicate that F-actin debranching organizes actin network and cell polarity in migrating neuroblasts and asymmetrically dividing embryos.
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21
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Mishra N, Heisenberg CP. Dissecting Organismal Morphogenesis by Bridging Genetics and Biophysics. Annu Rev Genet 2021; 55:209-233. [PMID: 34460295 DOI: 10.1146/annurev-genet-071819-103748] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Multicellular organisms develop complex shapes from much simpler, single-celled zygotes through a process commonly called morphogenesis. Morphogenesis involves an interplay between several factors, ranging from the gene regulatory networks determining cell fate and differentiation to the mechanical processes underlying cell and tissue shape changes. Thus, the study of morphogenesis has historically been based on multidisciplinary approaches at the interface of biology with physics and mathematics. Recent technological advances have further improved our ability to study morphogenesis by bridging the gap between the genetic and biophysical factors through the development of new tools for visualizing, analyzing, and perturbing these factors and their biochemical intermediaries. Here, we review how a combination of genetic, microscopic, biophysical, and biochemical approaches has aided our attempts to understand morphogenesis and discuss potential approaches that may be beneficial to such an inquiry in the future. Expected final online publication date for the Annual Review of Genetics, Volume 55 is November 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- Nikhil Mishra
- Institute of Science and Technology Austria, 3400 Klosterneuburg, Austria; ,
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22
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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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23
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Chaigne A, Smith MB, Lopez Cavestany R, Hannezo E, Chalut KJ, Paluch EK. Three-dimensional geometry controls division symmetry in stem cell colonies. J Cell Sci 2021; 134:jcs255018. [PMID: 34323278 PMCID: PMC8349555 DOI: 10.1242/jcs.255018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Accepted: 06/16/2021] [Indexed: 11/24/2022] Open
Abstract
Proper control of division orientation and symmetry, largely determined by spindle positioning, is essential to development and homeostasis. Spindle positioning has been extensively studied in cells dividing in two-dimensional (2D) environments and in epithelial tissues, where proteins such as NuMA (also known as NUMA1) orient division along the interphase long axis of the cell. However, little is known about how cells control spindle positioning in three-dimensional (3D) environments, such as early mammalian embryos and a variety of adult tissues. Here, we use mouse embryonic stem cells (ESCs), which grow in 3D colonies, as a model to investigate division in 3D. We observe that, at the periphery of 3D colonies, ESCs display high spindle mobility and divide asymmetrically. Our data suggest that enhanced spindle movements are due to unequal distribution of the cell-cell junction protein E-cadherin between future daughter cells. Interestingly, when cells progress towards differentiation, division becomes more symmetric, with more elongated shapes in metaphase and enhanced cortical NuMA recruitment in anaphase. Altogether, this study suggests that in 3D contexts, the geometry of the cell and its contacts with neighbors control division orientation and symmetry. This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Agathe Chaigne
- MRC Laboratory for Molecular Cell Biology, University College London, London WC1E 6BT, UK
| | - Matthew B. Smith
- MRC Laboratory for Molecular Cell Biology, University College London, London WC1E 6BT, UK
| | - Rocio Lopez Cavestany
- MRC Laboratory for Molecular Cell Biology, University College London, London WC1E 6BT, UK
| | | | - Kevin J. Chalut
- Wellcome/MRC Stem Cell Institute, University of Cambridge, Cambridge CB2 0AW, UK
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3DY, UK
| | - Ewa K. Paluch
- MRC Laboratory for Molecular Cell Biology, University College London, London WC1E 6BT, UK
- Wellcome/MRC Stem Cell Institute, University of Cambridge, Cambridge CB2 0AW, UK
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3DY, UK
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24
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Han X, Su Y, White H, O'Neill KM, Morgan NY, Christensen R, Potarazu D, Vishwasrao HD, Xu S, Sun Y, Huang SY, Moyle MW, Dai Q, Pommier Y, Giniger E, Albrecht DR, Probst R, Shroff H. A polymer index-matched to water enables diverse applications in fluorescence microscopy. LAB ON A CHIP 2021; 21:1549-1562. [PMID: 33629685 PMCID: PMC8058278 DOI: 10.1039/d0lc01233e] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
We demonstrate diffraction-limited and super-resolution imaging through thick layers (tens-hundreds of microns) of BIO-133, a biocompatible, UV-curable, commercially available polymer with a refractive index (RI) matched to water. We show that cells can be directly grown on BIO-133 substrates without the need for surface passivation and use this capability to perform extended time-lapse volumetric imaging of cellular dynamics 1) at isotropic resolution using dual-view light-sheet microscopy, and 2) at super-resolution using instant structured illumination microscopy. BIO-133 also enables immobilization of 1) Drosophila tissue, allowing us to track membrane puncta in pioneer neurons, and 2) Caenorhabditis elegans, which allows us to image and inspect fine neural structure and to track pan-neuronal calcium activity over hundreds of volumes. Finally, BIO-133 is compatible with other microfluidic materials, enabling optical and chemical perturbation of immobilized samples, as we demonstrate by performing drug and optogenetic stimulation on cells and C. elegans.
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Affiliation(s)
- Xiaofei Han
- Laboratory of High Resolution Optical Imaging, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD 20892, USA. and Department of Automation, Tsinghua University, Beijing, 100084, China.
| | - Yijun Su
- Laboratory of High Resolution Optical Imaging, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD 20892, USA. and Advanced Imaging and Microscopy Resource, National Institutes of Health, Bethesda, MD 20892, USA
| | - Hamilton White
- Department of Biomedical Engineering, Worcester Polytechnic Institute, 100 Institute Road, Worcester, MA 01609, USA. and Department of Neurobiology, University of Massachusetts Medical School, Worcester, MA 01655, USA
| | - Kate M O'Neill
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA and Institute for Physical Science and Technology, University of Maryland College Park, College Park, MD 20742, USA
| | - Nicole Y Morgan
- National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD 20892, USA
| | - Ryan Christensen
- Laboratory of High Resolution Optical Imaging, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Deepika Potarazu
- Laboratory of High Resolution Optical Imaging, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Harshad D Vishwasrao
- Advanced Imaging and Microscopy Resource, National Institutes of Health, Bethesda, MD 20892, USA
| | - Stephen Xu
- Laboratory of High Resolution Optical Imaging, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Yilun Sun
- Developmental Therapeutics Branch and Laboratory of Molecular Pharmacology, Center for Cancer Research, National Institutes of Health, Bethesda, MD 20892, USA
| | - Shar-Yin Huang
- Developmental Therapeutics Branch and Laboratory of Molecular Pharmacology, Center for Cancer Research, National Institutes of Health, Bethesda, MD 20892, USA
| | - Mark W Moyle
- Department of Neuroscience and Department of Cell Biology, Yale University School of Medicine, New Haven, CT 06536, USA
| | - Qionghai Dai
- Department of Automation, Tsinghua University, Beijing, 100084, China.
| | - Yves Pommier
- Developmental Therapeutics Branch and Laboratory of Molecular Pharmacology, Center for Cancer Research, National Institutes of Health, Bethesda, MD 20892, USA
| | - Edward Giniger
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
| | - Dirk R Albrecht
- Department of Biomedical Engineering, Worcester Polytechnic Institute, 100 Institute Road, Worcester, MA 01609, USA. and Department of Biology and Biotechnology, Worcester Polytechnic Institute, 100 Institute Road, Worcester, MA 01609, USA
| | - Roland Probst
- ACUITYnano, Innovation in Biomedical Imaging, North Bethesda, MD 20850, USA
| | - Hari Shroff
- Laboratory of High Resolution Optical Imaging, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD 20892, USA. and Advanced Imaging and Microscopy Resource, National Institutes of Health, Bethesda, MD 20892, USA and Marine Biological Laboratory Fellows Program, Woods Hole, MA 02543, USA
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25
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Jankele R, Jelier R, Gönczy P. Physically asymmetric division of the C. elegans zygote ensures invariably successful embryogenesis. eLife 2021; 10:e61714. [PMID: 33620314 PMCID: PMC7972452 DOI: 10.7554/elife.61714] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Accepted: 02/22/2021] [Indexed: 12/17/2022] Open
Abstract
Asymmetric divisions that yield daughter cells of different sizes are frequent during early embryogenesis, but the importance of such a physical difference for successful development remains poorly understood. Here, we investigated this question using the first division of Caenorhabditis elegans embryos, which yields a large AB cell and a small P1 cell. We equalized AB and P1 sizes using acute genetic inactivation or optogenetic manipulation of the spindle positioning protein LIN-5. We uncovered that only some embryos tolerated equalization, and that there was a size asymmetry threshold for viability. Cell lineage analysis of equalized embryos revealed an array of defects, including faster cell cycle progression in P1 descendants, as well as defects in cell positioning, division orientation, and cell fate. Moreover, equalized embryos were more susceptible to external compression. Overall, we conclude that unequal first cleavage is essential for invariably successful embryonic development of C. elegans.
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Affiliation(s)
- Radek Jankele
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology Lausanne (EPFL)LausanneSwitzerland
| | - Rob Jelier
- Centre of Microbial and Plant Genetics, Katholieke Universiteit LeuvenLeuvenBelgium
| | - Pierre Gönczy
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology Lausanne (EPFL)LausanneSwitzerland
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Magliozzi JO, Moseley JB. Connecting cell polarity signals to the cytokinetic machinery in yeast and metazoan cells. Cell Cycle 2021; 20:1-10. [PMID: 33397181 DOI: 10.1080/15384101.2020.1864941] [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: 10/22/2022] Open
Abstract
Polarized growth and cytokinesis are two fundamental cellular processes that exist in virtually all cell types. Mechanisms for asymmetric distribution of materials allow for cells to grow in a polarized manner. This gives rise to a variety of cell shapes seen throughout all cell types. Following polarized growth during interphase, dividing cells assemble a cytokinetic ring containing the protein machinery to constrict and separate daughter cells. Here, we discuss how cell polarity signaling pathways act on cytokinesis, with a focus on direct regulation of the contractile actomyosin ring (CAR). Recent studies have exploited phosphoproteomics to identify new connections between cell polarity kinases and CAR proteins. Existing evidence suggests that some polarity kinases guide the local organization of CAR proteins and structures while also contributing to global organization of the division plane within a cell. We provide several examples of this regulation from budding yeast, fission yeast, and metazoan cells. In some cases, kinase-substrate connections point to conserved processes in these different organisms. We point to several examples where future work can indicate the degree of conservation and divergence in the cell division process of these different organisms.
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Affiliation(s)
- Joseph O Magliozzi
- Department of Biochemistry and Cell Biology, The Geisel School of Medicine at Dartmouth , Hanover, New Hampshire, USA
| | - James B Moseley
- Department of Biochemistry and Cell Biology, The Geisel School of Medicine at Dartmouth , Hanover, New Hampshire, USA
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27
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Gubieda AG, Packer JR, Squires I, Martin J, Rodriguez J. Going with the flow: insights from Caenorhabditis elegans zygote polarization. Philos Trans R Soc Lond B Biol Sci 2020; 375:20190555. [PMID: 32829680 PMCID: PMC7482210 DOI: 10.1098/rstb.2019.0555] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/09/2020] [Indexed: 12/12/2022] Open
Abstract
Cell polarity is the asymmetric distribution of cellular components along a defined axis. Polarity relies on complex signalling networks between conserved patterning proteins, including the PAR (partitioning defective) proteins, which become segregated in response to upstream symmetry breaking cues. Although the mechanisms that drive the asymmetric localization of these proteins are dependent upon cell type and context, in many cases the regulation of actomyosin cytoskeleton dynamics is central to the transport, recruitment and/or stabilization of these polarity effectors into defined subcellular domains. The transport or advection of PAR proteins by an actomyosin flow was first observed in the Caenorhabditis elegans zygote more than a decade ago. Since then a multifaceted approach, using molecular methods, high-throughput screens, and biophysical and computational models, has revealed further aspects of this flow and how polarity regulators respond to and modulate it. Here, we review recent findings on the interplay between actomyosin flow and the PAR patterning networks in the polarization of the C. elegans zygote. We also discuss how these discoveries and developed methods are shaping our understanding of other flow-dependent polarizing systems. This article is part of a discussion meeting issue 'Contemporary morphogenesis'.
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Affiliation(s)
| | | | | | | | - Josana Rodriguez
- Biosciences Institute, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
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28
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Kelkar M, Bohec P, Charras G. Mechanics of the cellular actin cortex: From signalling to shape change. Curr Opin Cell Biol 2020; 66:69-78. [DOI: 10.1016/j.ceb.2020.05.008] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 03/30/2020] [Accepted: 05/08/2020] [Indexed: 01/17/2023]
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Chaigne A, Labouesse C, White IJ, Agnew M, Hannezo E, Chalut KJ, Paluch EK. Abscission Couples Cell Division to Embryonic Stem Cell Fate. Dev Cell 2020; 55:195-208.e5. [PMID: 32979313 PMCID: PMC7594744 DOI: 10.1016/j.devcel.2020.09.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Revised: 06/22/2020] [Accepted: 08/30/2020] [Indexed: 12/30/2022]
Abstract
Cell fate transitions are key to development and homeostasis. It is thus essential to understand the cellular mechanisms controlling fate transitions. Cell division has been implicated in fate decisions in many stem cell types, including neuronal and epithelial progenitors. In other stem cells, such as embryonic stem (ES) cells, the role of division remains unclear. Here, we show that exit from naive pluripotency in mouse ES cells generally occurs after a division. We further show that exit timing is strongly correlated between sister cells, which remain connected by cytoplasmic bridges long after division, and that bridge abscission progressively accelerates as cells exit naive pluripotency. Finally, interfering with abscission impairs naive pluripotency exit, and artificially inducing abscission accelerates it. Altogether, our data indicate that a switch in the division machinery leading to faster abscission regulates pluripotency exit. Our study identifies abscission as a key cellular process coupling cell division to fate transitions. Mouse embryonic stem cells exit naive pluripotency after mitosis Naive embryonic stem cells display slow abscission and remain connected by bridges Cells exiting naive pluripotency display faster abscission Accelerating abscission facilitates exit from naive pluripotency
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Affiliation(s)
- Agathe Chaigne
- MRC Laboratory for Molecular Cell Biology, University College London, London WC1E 6BT, UK.
| | - Céline Labouesse
- Wellcome/MRC Cambridge Stem Cell Institute, University of Cambridge, Cambridge CB2 0AW, UK
| | - Ian J White
- MRC Laboratory for Molecular Cell Biology, University College London, London WC1E 6BT, UK
| | - Meghan Agnew
- MRC Laboratory for Molecular Cell Biology, University College London, London WC1E 6BT, UK
| | - Edouard Hannezo
- Institute of Science and Technology Austria, Klosterneuburg 3400, Austria
| | - Kevin J Chalut
- Wellcome/MRC Cambridge Stem Cell Institute, University of Cambridge, Cambridge CB2 0AW, UK
| | - Ewa K Paluch
- MRC Laboratory for Molecular Cell Biology, University College London, London WC1E 6BT, UK; Wellcome/MRC Cambridge Stem Cell Institute, University of Cambridge, Cambridge CB2 0AW, UK; Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3DY, UK.
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30
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PIG-1 MELK-dependent phosphorylation of nonmuscle myosin II promotes apoptosis through CES-1 Snail partitioning. PLoS Genet 2020; 16:e1008912. [PMID: 32946434 PMCID: PMC7527206 DOI: 10.1371/journal.pgen.1008912] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Revised: 09/30/2020] [Accepted: 07/29/2020] [Indexed: 01/06/2023] Open
Abstract
The mechanism(s) through which mammalian kinase MELK promotes tumorigenesis is not understood. We find that the C. elegans orthologue of MELK, PIG-1, promotes apoptosis by partitioning an anti-apoptotic factor. The C. elegans NSM neuroblast divides to produce a larger cell that differentiates into a neuron and a smaller cell that dies. We find that in this context, PIG-1 MELK is required for partitioning of CES-1 Snail, a transcriptional repressor of the pro-apoptotic gene egl-1 BH3-only. pig-1 MELK is controlled by both a ces-1 Snail- and par-4 LKB1-dependent pathway, and may act through phosphorylation and cortical enrichment of nonmuscle myosin II prior to neuroblast division. We propose that pig-1 MELK-induced local contractility of the actomyosin network plays a conserved role in the acquisition of the apoptotic fate. Our work also uncovers an auto-regulatory loop through which ces-1 Snail controls its own activity through the formation of a gradient of CES-1 Snail protein. Apoptosis is critical for the elimination of ‘unwanted’ cells. What distinguishes wanted from unwanted cells in developing animals is poorly understood. We report that in the C. elegans NSM neuroblast lineage, the level of CES-1, a Snail-family member and transcriptional repressor of the pro-apoptotic gene egl-1, contributes to this process. In addition, we demonstrate that C. elegans PIG-1, the orthologue of mammalian proto-oncoprotein MELK, plays a critical role in controlling CES-1Snail levels. Specifically, during NSM neuroblast division, PIG-1MELK controls partitioning of CES-1Snail into one but not the other daughter cell thereby promoting the making of one wanted and one unwanted cell. Furthermore, we present evidence that PIG-1MELK acts prior to NSM neuroblast division by locally activating the actomyosin network.
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Abstract
Asymmetric cell division (ACD) is an evolutionarily conserved mechanism used by prokaryotes and eukaryotes alike to control cell fate and generate cell diversity. A detailed mechanistic understanding of ACD is therefore necessary to understand cell fate decisions in health and disease. ACD can be manifested in the biased segregation of macromolecules, the differential partitioning of cell organelles, or differences in sibling cell size or shape. These events are usually preceded by and influenced by symmetry breaking events and cell polarization. In this Review, we focus predominantly on cell intrinsic mechanisms and their contribution to cell polarization, ACD and binary cell fate decisions. We discuss examples of polarized systems and detail how polarization is established and, whenever possible, how it contributes to ACD. Established and emerging model organisms will be considered alike, illuminating both well-documented and underexplored forms of polarization and ACD.
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Affiliation(s)
- Bharath Sunchu
- Department of Biology, University of Washington, Life Science Building, Seattle, WA 98195, USA
| | - Clemens Cabernard
- Department of Biology, University of Washington, Life Science Building, Seattle, WA 98195, USA
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Wang H, Guo X, Wang X, Wang X, Chen J. Supracellular Actomyosin Mediates Cell-Cell Communication and Shapes Collective Migratory Morphology. iScience 2020; 23:101204. [PMID: 32535019 PMCID: PMC7300135 DOI: 10.1016/j.isci.2020.101204] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 03/23/2020] [Accepted: 05/26/2020] [Indexed: 01/27/2023] Open
Abstract
During collective cell migration, front cells tend to extend a predominant leading protrusion, which is rarely present in cells at the side or rear positions. Using Drosophila border cells (BCs) as a model system of collective migration, we revealed the presence of a supracellular actomyosin network at the peripheral surface of BC clusters. We demonstrated that the Myosin II-mediated mechanical tension as exerted by this peripheral supracellular network not only mediated cell-cell communication between leading BC and non-leading BCs but also restrained formation of prominent protrusions at non-leading BCs. Further analysis revealed that a cytoplasmic dendritic actin network that depends on the function of Arp2/3 complex interacted with the actomyosin network. Together, our data suggest that the outward pushing or protrusive force as generated from Arp2/3-dependent actin polymerization and the inward restraining force as produced from the supracellular actomyosin network together determine the collective and polarized morphology of migratory BCs.
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Affiliation(s)
- Heng Wang
- State Key Laboratory of Pharmaceutical Biotechnology and MOE Key Laboratory of Model Animals for Disease Study, Model Animal Research Center, Nanjing University, 12 Xue-fu Road, Nanjing 210061, China.
| | - Xuan Guo
- State Key Laboratory of Pharmaceutical Biotechnology and MOE Key Laboratory of Model Animals for Disease Study, Model Animal Research Center, Nanjing University, 12 Xue-fu Road, Nanjing 210061, China
| | - Xianping Wang
- State Key Laboratory of Pharmaceutical Biotechnology and MOE Key Laboratory of Model Animals for Disease Study, Model Animal Research Center, Nanjing University, 12 Xue-fu Road, Nanjing 210061, China
| | - Xiaobo Wang
- LBCMCP, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, 31062 Toulouse, France
| | - Jiong Chen
- State Key Laboratory of Pharmaceutical Biotechnology and MOE Key Laboratory of Model Animals for Disease Study, Model Animal Research Center, Nanjing University, 12 Xue-fu Road, Nanjing 210061, China.
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33
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Bai X, Melesse M, Sorensen Turpin CG, Sloan DE, Chen CY, Wang WC, Lee PY, Simmons JR, Nebenfuehr B, Mitchell D, Klebanow LR, Mattson N, Betzig E, Chen BC, Cheerambathur D, Bembenek JN. Aurora B functions at the apical surface after specialized cytokinesis during morphogenesis in C. elegans. Development 2020; 147:dev.181099. [PMID: 31806662 PMCID: PMC6983721 DOI: 10.1242/dev.181099] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Accepted: 11/26/2019] [Indexed: 12/18/2022]
Abstract
Although cytokinesis has been intensely studied, the way it is executed during development is not well understood, despite a long-standing appreciation that various aspects of cytokinesis vary across cell and tissue types. To address this, we investigated cytokinesis during the invariant Caenorhabditis elegans embryonic divisions and found several parameters that are altered at different stages in a reproducible manner. During early divisions, furrow ingression asymmetry and midbody inheritance is consistent, suggesting specific regulation of these events. During morphogenesis, we found several unexpected alterations to cytokinesis, including apical midbody migration in polarizing epithelial cells of the gut, pharynx and sensory neurons. Aurora B kinase, which is essential for several aspects of cytokinesis, remains apically localized in each of these tissues after internalization of midbody ring components. Aurora B inactivation disrupts cytokinesis and causes defects in apical structures, even if inactivated post-mitotically. Therefore, we demonstrate that cytokinesis is implemented in a specialized way during epithelial polarization and that Aurora B has a role in the formation of the apical surface.
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Affiliation(s)
- Xiaofei Bai
- Department of Biochemistry, Cellular and Molecular Biology, University of Tennessee, Knoxville, TN 37996, USA
| | - Michael Melesse
- Department of Biochemistry, Cellular and Molecular Biology, University of Tennessee, Knoxville, TN 37996, USA
| | | | - Dillon E. Sloan
- Department of Biochemistry, Cellular and Molecular Biology, University of Tennessee, Knoxville, TN 37996, USA,Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Chin-Yi Chen
- Research Center for Applied Sciences, Academia Sinica, Taipei, Taiwan
| | - Wen-Cheng Wang
- Research Center for Applied Sciences, Academia Sinica, Taipei, Taiwan
| | - Po-Yi Lee
- Research Center for Applied Sciences, Academia Sinica, Taipei, Taiwan
| | - James R. Simmons
- Department of Biochemistry, Cellular and Molecular Biology, University of Tennessee, Knoxville, TN 37996, USA
| | - Benjamin Nebenfuehr
- Department of Biochemistry, Cellular and Molecular Biology, University of Tennessee, Knoxville, TN 37996, USA
| | - Diana Mitchell
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Lindsey R. Klebanow
- Department of Biochemistry, Cellular and Molecular Biology, University of Tennessee, Knoxville, TN 37996, USA
| | - Nicholas Mattson
- Department of Biochemistry, Cellular and Molecular Biology, University of Tennessee, Knoxville, TN 37996, USA
| | - Eric Betzig
- Janelia Research Campus, HHMI, Ashburn, VA 20147, USA
| | - Bi-Chang Chen
- Research Center for Applied Sciences, Academia Sinica, Taipei, Taiwan,Janelia Research Campus, HHMI, Ashburn, VA 20147, USA
| | - Dhanya Cheerambathur
- Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh, EH9 3BF, UK
| | - Joshua N. Bembenek
- Department of Biochemistry, Cellular and Molecular Biology, University of Tennessee, Knoxville, TN 37996, USA,Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA,Author for correspondence ()
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Pacquelet A, Jousseaume M, Etienne J, Michaux G. Simultaneous Regulation of Cytokinetic Furrow and Nucleus Positions by Cortical Tension Contributes to Proper DNA Segregation during Late Mitosis. Curr Biol 2019; 29:3766-3777.e4. [PMID: 31679940 DOI: 10.1016/j.cub.2019.09.013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Revised: 08/13/2019] [Accepted: 09/06/2019] [Indexed: 10/25/2022]
Abstract
Coordinating mitotic spindle and cytokinetic furrow positioning is essential to ensure proper DNA segregation. Here, we present a novel mechanism, which corrects DNA segregation defects due to cytokinetic furrow mispositioning during the first division of C. elegans embryos. Correction of DNA segregation defects due to an abnormally anterior cytokinetic furrow relies on the concomitant and opposite displacements of the furrow and of the anterior nucleus toward the posterior and anterior poles of the embryo, respectively. It also coincides with cortical blebbing and an anteriorly directed cytoplasmic flow. Although microtubules contribute to nuclear displacement, relaxation of an excessive tension at the anterior cortex plays a central role in the correction process and simultaneously regulates cytoplasmic flow as well as nuclear and furrow displacements. This work thus reveals the existence of a so-far uncharacterized correction mechanism, which is critical to correct DNA segregation defects due to cytokinetic furrow mispositioning.
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Affiliation(s)
- Anne Pacquelet
- Univ Rennes, CNRS, IGDR (Institut de Génétique et de Développement de Rennes), UMR 6290, 2 Avenue du Professeur Léon Bernard, 35000 Rennes, France.
| | - Matthieu Jousseaume
- Univ Rennes, CNRS, IGDR (Institut de Génétique et de Développement de Rennes), UMR 6290, 2 Avenue du Professeur Léon Bernard, 35000 Rennes, France
| | - Jocelyn Etienne
- Univ Grenoble Alpes, CNRS, LIPhy, 140 Avenue de la Physique, 38402 Saint Martin d'Hères, France
| | - Grégoire Michaux
- Univ Rennes, CNRS, IGDR (Institut de Génétique et de Développement de Rennes), UMR 6290, 2 Avenue du Professeur Léon Bernard, 35000 Rennes, France
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35
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Winkley K, Ward S, Reeves W, Veeman M. Iterative and Complex Asymmetric Divisions Control Cell Volume Differences in Ciona Notochord Tapering. Curr Biol 2019; 29:3466-3477.e4. [PMID: 31607534 DOI: 10.1016/j.cub.2019.08.056] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 07/29/2019] [Accepted: 08/21/2019] [Indexed: 12/12/2022]
Abstract
The notochord of the invertebrate chordate Ciona forms a tapered rod at tailbud stages consisting of only 40 cylindrical cells in a single-file column. This tapered shape involves differences in notochord cell volume along the anterior-posterior axis. Here, we quantify sibling cell volume asymmetry throughout the developing notochord and find that there are distinctive patterns of unequal cleavage in all 4 bilateral pairs of A-line primary notochord founder cells and also in the B-line-derived secondary notochord founder cells. A quantitative model confirms that the observed patterns of unequal cleavage are sufficient to explain all the anterior-posterior variation in notochord cell volume. Many examples are known of cells that divide asymmetrically to give daughter cells of different size and fate. Here, by contrast, a series of subtle but iterative and finely patterned asymmetric divisions controls the shape of an entire organ. Quantitative 3D analysis of cell shape and spindle positioning allows us to infer multiple cellular mechanisms driving these unequal cleavages, including polarized displacements of the mitotic spindle, contributions from the shape of the mother cell, and late changes occurring between anaphase and abscission that potentially involve differential cortical contractility. We infer differential use of these mechanisms between different notochord blastomeres and also between different rounds of cell division. These results demonstrate a new role for asymmetric division in directly shaping a developing organ and point toward complex underlying mechanisms.
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Affiliation(s)
- Konner Winkley
- Division of Biology, Kansas State University, 1717 Claflin Road, Manhattan, KS 66506, USA
| | - Spencer Ward
- Division of Biology, Kansas State University, 1717 Claflin Road, Manhattan, KS 66506, USA
| | - Wendy Reeves
- Division of Biology, Kansas State University, 1717 Claflin Road, Manhattan, KS 66506, USA
| | - Michael Veeman
- Division of Biology, Kansas State University, 1717 Claflin Road, Manhattan, KS 66506, USA.
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36
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Hubatsch L, Peglion F, Reich JD, Rodrigues NTL, Hirani N, Illukkumbura R, Goehring NW. A cell size threshold limits cell polarity and asymmetric division potential. NATURE PHYSICS 2019; 15:1075-1085. [PMID: 31579399 PMCID: PMC6774796 DOI: 10.1038/s41567-019-0601-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Accepted: 06/21/2019] [Indexed: 05/18/2023]
Abstract
Reaction-diffusion networks underlie pattern formation in a range of biological contexts, from morphogenesis of organisms to the polarisation of individual cells. One requirement for such molecular networks is that output patterns be scaled to system size. At the same time, kinetic properties of constituent molecules constrain the ability of networks to adapt to size changes. Here we explore these constraints and the consequences thereof within the conserved PAR cell polarity network. Using the stem cell-like germ lineage of the C. elegans embryo as a model, we find that the behaviour of PAR proteins fails to scale with cell size. Theoretical analysis demonstrates that this lack of scaling results in a size threshold below which polarity is destabilized, yielding an unpolarized system. In empirically-constrained models, this threshold occurs near the size at which germ lineage cells normally switch between asymmetric and symmetric modes of division. Consistent with cell size limiting polarity and division asymmetry, genetic or physical reduction in germ lineage cell size is sufficient to trigger loss of polarity in normally polarizing cells at predicted size thresholds. Physical limits of polarity networks may be one mechanism by which cells read out geometrical features to inform cell fate decisions.
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Affiliation(s)
- Lars Hubatsch
- The Francis Crick Institute, London, NW1 1AT, UK
- Institute for the Physics of Living Systems, University College
London, London, WC1E 6BT, UK
| | | | | | | | - Nisha Hirani
- The Francis Crick Institute, London, NW1 1AT, UK
| | | | - Nathan W Goehring
- The Francis Crick Institute, London, NW1 1AT, UK
- MRC Laboratory for Molecular Cell Biology, University College
London, London, WC1E 6BT, UK
- Institute for the Physics of Living Systems, University College
London, London, WC1E 6BT, UK
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37
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Pham TT, Monnard A, Helenius J, Lund E, Lee N, Müller DJ, Cabernard C. Spatiotemporally Controlled Myosin Relocalization and Internal Pressure Generate Sibling Cell Size Asymmetry. iScience 2019; 13:9-19. [PMID: 30785031 PMCID: PMC6383127 DOI: 10.1016/j.isci.2019.02.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Revised: 11/12/2018] [Accepted: 01/30/2019] [Indexed: 11/24/2022] Open
Abstract
Metazoan cells can generate unequal-sized sibling cells during cell division. This form of asymmetric cell division depends on spindle geometry and Myosin distribution, but the underlying mechanics are unclear. Here, we use atomic force microscopy and live cell imaging to elucidate the biophysical forces involved in the establishment of physical asymmetry in Drosophila neural stem cells. We show that initial apical cortical expansion is driven by hydrostatic pressure, peaking shortly after anaphase onset, and enabled by a relief of actomyosin contractile tension on the apical cell cortex. An increase in contractile tension at the cleavage furrow combined with the relocalization of basally located Myosin initiates basal and sustains apical extension. We propose that spatiotemporally controlled actomyosin contractile tension and hydrostatic pressure enable biased cortical expansion to generate sibling cell size asymmetry. However, dynamic cleavage furrow repositioning can compensate for the lack of biased expansion to establish physical asymmetry.
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Affiliation(s)
- Tri Thanh Pham
- Department of Biology, University of Washington, Life Science Building, Seattle, WA 98195, USA
| | - Arnaud Monnard
- Department of Biology, University of Washington, Life Science Building, Seattle, WA 98195, USA; Biozentrum, University of Basel, Klingelbergstrasse 50-70, 4056 Basel, Switzerland
| | - Jonne Helenius
- Eidgenössische Technische Hochschule (ETH) Zurich, Department of Biosystems Science and Engineering, Mattenstrasse 26, 4058 Basel, Switzerland
| | - Erik Lund
- Department of Biology, University of Washington, Life Science Building, Seattle, WA 98195, USA
| | - Nicole Lee
- Department of Biology, University of Washington, Life Science Building, Seattle, WA 98195, USA; Cancer Science Institute, National University of Singapore, 14 Medical Dr., Singapore 117599, Singapore
| | - Daniel J Müller
- Eidgenössische Technische Hochschule (ETH) Zurich, Department of Biosystems Science and Engineering, Mattenstrasse 26, 4058 Basel, Switzerland
| | - Clemens Cabernard
- Department of Biology, University of Washington, Life Science Building, Seattle, WA 98195, USA.
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38
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Molecular evidence for distinct modes of nutrient acquisition between visceral and neurotropic schistosomes of birds. Sci Rep 2019; 9:1347. [PMID: 30718911 PMCID: PMC6362228 DOI: 10.1038/s41598-018-37669-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Accepted: 12/10/2018] [Indexed: 12/19/2022] Open
Abstract
Trichobilharzia species are parasitic flatworms (called schistosomes or flukes) that cause important diseases in birds and humans, but very little is known about their molecular biology. Here, using a transcriptomics-bioinformatics-based approach, we explored molecular aspects pertaining to the nutritional requirements of Trichobilharzia szidati (‘visceral fluke’) and T. regenti (‘neurotropic fluke’) in their avian host. We studied the larvae of each species before they enter (cercariae) and as they migrate (schistosomules) through distinct tissues in their avian (duck) host. Cercariae of both species were enriched for pathways or molecules associated predominantly with carbohydrate metabolism, oxidative phosphorylation and translation of proteins linked to ribosome biogenesis, exosome production and/or lipid biogenesis. Schistosomules of both species were enriched for pathways or molecules associated with processes including signal transduction, cell turnover and motility, DNA replication and repair, molecular transport and/or catabolism. Comparative informatic analyses identified molecular repertoires (within, e.g., peptidases and secretory proteins) in schistosomules that can broadly degrade macromolecules in both T. szidati and T. regenti, and others that are tailored to each species to selectively acquire nutrients from particular tissues through which it migrates. Thus, this study provides molecular evidence for distinct modes of nutrient acquisition between the visceral and neurotropic flukes of birds.
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39
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He CW, Liao CP, Chen CK, Teulière J, Chen CH, Pan CL. The polarity protein VANG-1 antagonizes Wnt signaling by facilitating Frizzled endocytosis. Development 2018; 145:dev.168666. [PMID: 30504124 DOI: 10.1242/dev.168666] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Accepted: 11/16/2018] [Indexed: 01/17/2023]
Abstract
Signaling that instructs the migration of neurons needs to be tightly regulated to ensure precise positioning of neurons and subsequent wiring of the neuronal circuits. Wnt-Frizzled signaling controls neuronal migration in metazoans, in addition to many other aspects of neural development. We show that Caenorhabditis elegans VANG-1, a membrane protein that acts in the planar cell polarity (PCP) pathway, antagonizes Wnt signaling by facilitating endocytosis of the Frizzled receptors. Mutations of vang-1 suppress migration defects of multiple classes of neurons in the Frizzled mutants, and overexpression of vang-1 causes neuronal migration defects similar to those of the Frizzled mutants. Our genetic experiments suggest that VANG-1 facilitates Frizzled endocytosis through β-arrestin2. Co-immunoprecipitation experiments indicate that Frizzled proteins and VANG-1 form a complex, and this physical interaction requires the Frizzled cysteine-rich domain. Our work reveals a novel mechanism mediated by the PCP protein VANG-1 that downregulates Wnt signaling through Frizzled endocytosis.
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Affiliation(s)
- Chun-Wei He
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei 10002, Taiwan
| | - Chien-Po Liao
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei 10002, Taiwan
| | - Chung-Kuan Chen
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei 10002, Taiwan
| | - Jérôme Teulière
- Department of Molecular Cell Biology, University of California, Berkeley, CA 94720-3204, USA
| | - Chun-Hao Chen
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei 10002, Taiwan
| | - Chun-Liang Pan
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei 10002, Taiwan
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40
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Mishra N, Wei H, Conradt B. Caenorhabditis elegans ced-3 Caspase Is Required for Asymmetric Divisions That Generate Cells Programmed To Die. Genetics 2018; 210:983-998. [PMID: 30194072 PMCID: PMC6218217 DOI: 10.1534/genetics.118.301500] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2018] [Accepted: 09/04/2018] [Indexed: 01/30/2023] Open
Abstract
Caspases have functions other than in apoptosis. Here, we report that Caenorhabditis elegans CED-3 caspase regulates asymmetric cell division. Many of the 131 cells that are "programmed" to die during C. elegans development are the smaller daughter of a neuroblast that divides asymmetrically by size and fate. We have previously shown that CED-3 caspase is activated in such neuroblasts, and that before neuroblast division, a gradient of CED-3 caspase activity is formed in a ced-1 MEGF10 ( m ultiple EGF -like domains 10 )-dependent manner. This results in the nonrandom segregation of active CED-3 caspase or "apoptotic potential" into the smaller daughter. We now show that CED-3 caspase is necessary for the ability of neuroblasts to divide asymmetrically by size. In addition, we provide evidence that a pig-1 MELK (maternal embryonic leucine zipper kinase)-dependent reciprocal gradient of "mitotic potential" is formed in the QL.p neuroblast, and that CED-3 caspase antagonizes this mitotic potential. Based on these findings, we propose that CED-3 caspase plays a critical role in the asymmetric division by size and fate of neuroblasts, and that this contributes to the reproducibility and robustness with which the smaller daughter cell is produced and adopts the apoptotic fate. Finally, the function of CED-3 caspase in this context is dependent on its activation through the conserved egl-1 BH3-only, ced-9 Bcl-2, and ced-4 Apaf-1 pathway. In mammals, caspases affect various aspects of stem cell lineages. We speculate that the new nonapoptotic function of C. elegans CED-3 caspase in asymmetric neuroblast division is relevant to the function(s) of mammalian caspases in stem cells.
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Affiliation(s)
- Nikhil Mishra
- Faculty of Biology, Center for Integrated Protein Science Munich, Ludwig-Maximilians-University Munich, 82152 Planegg-Martinsried, Germany
| | - Hai Wei
- Faculty of Biology, Center for Integrated Protein Science Munich, Ludwig-Maximilians-University Munich, 82152 Planegg-Martinsried, Germany
| | - Barbara Conradt
- Faculty of Biology, Center for Integrated Protein Science Munich, Ludwig-Maximilians-University Munich, 82152 Planegg-Martinsried, Germany
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41
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Combinatorial Contact Cues Specify Cell Division Orientation by Directing Cortical Myosin Flows. Dev Cell 2018; 46:257-270.e5. [PMID: 30032990 PMCID: PMC7695482 DOI: 10.1016/j.devcel.2018.06.020] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Revised: 04/13/2018] [Accepted: 06/22/2018] [Indexed: 12/31/2022]
Abstract
Cell division axes during development are specified in different orientations to establish multicellular assemblies, but the mechanisms that generate division axis diversity remain unclear. We show here that patterns of cell contact provide cues that diversify cell division orientation by modulating cortical non-muscle myosin flow. We reconstituted in vivo contact patterns using beads or isolated cells to show two findings. First, we identified three contact-dependent cues that pattern cell division orientation and myosin flow: physical contact, contact asymmetry, and a Wnt signal. Second, we experimentally demonstrated that myosin flow generates forces that trigger plasma membrane movements and propose that their anisotropy drives cell division orientation. Our data suggest that contact-dependent control of myosin specifies the division axes of Caenorhabditis elegans AB, ABa, EMS cells, and the mouse AB cell. The contact pattern-dependent generation of myosin flows, in concert with known microtubule/dynein pathways, may greatly expand division axis diversity during development.
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42
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Abstract
Precisely controlled cell deformations are key to cell migration, division and tissue morphogenesis, and have been implicated in cell differentiation during development, as well as cancer progression. In animal cells, shape changes are primarily driven by the cellular cortex, a thin actomyosin network that lies directly underneath the plasma membrane. Myosin-generated forces create tension in the cortical network, and gradients in tension lead to cellular deformations. Recent studies have provided important insight into the molecular control of cortical tension by progressively unveiling cortex composition and organization. In this Cell Science at a Glance article and the accompanying poster, we review our current understanding of cortex composition and architecture. We then discuss how the microscopic properties of the cortex control cortical tension. While many open questions remain, it is now clear that cortical tension can be modulated through both cortex composition and organization, providing multiple levels of regulation for this key cellular property during cell and tissue morphogenesis. Summary: A summary of the composition, architecture, mechanics and function of the cellular actin cortex, which determines the shape of animal cells, and, thus, provides the foundation for cell and tissue morphogenesis.
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Affiliation(s)
- Priyamvada Chugh
- MRC Laboratory for Molecular Cell Biology, University College London, London WC1E 6BT, UK .,Institute for the Physics of Living Systems, University College London, London WC1E 6BT, UK
| | - Ewa K Paluch
- MRC Laboratory for Molecular Cell Biology, University College London, London WC1E 6BT, UK .,Institute for the Physics of Living Systems, University College London, London WC1E 6BT, UK.,Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3DY, UK
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43
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Gnesotto FS, Mura F, Gladrow J, Broedersz CP. Broken detailed balance and non-equilibrium dynamics in living systems: a review. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2018; 81:066601. [PMID: 29504517 DOI: 10.1088/1361-6633/aab3ed] [Citation(s) in RCA: 116] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Living systems operate far from thermodynamic equilibrium. Enzymatic activity can induce broken detailed balance at the molecular scale. This molecular scale breaking of detailed balance is crucial to achieve biological functions such as high-fidelity transcription and translation, sensing, adaptation, biochemical patterning, and force generation. While biological systems such as motor enzymes violate detailed balance at the molecular scale, it remains unclear how non-equilibrium dynamics manifests at the mesoscale in systems that are driven through the collective activity of many motors. Indeed, in several cellular systems the presence of non-equilibrium dynamics is not always evident at large scales. For example, in the cytoskeleton or in chromosomes one can observe stationary stochastic processes that appear at first glance thermally driven. This raises the question how non-equilibrium fluctuations can be discerned from thermal noise. We discuss approaches that have recently been developed to address this question, including methods based on measuring the extent to which the system violates the fluctuation-dissipation theorem. We also review applications of this approach to reconstituted cytoskeletal networks, the cytoplasm of living cells, and cell membranes. Furthermore, we discuss a more recent approach to detect actively driven dynamics, which is based on inferring broken detailed balance. This constitutes a non-invasive method that uses time-lapse microscopy data, and can be applied to a broad range of systems in cells and tissue. We discuss the ideas underlying this method and its application to several examples including flagella, primary cilia, and cytoskeletal networks. Finally, we briefly discuss recent developments in stochastic thermodynamics and non-equilibrium statistical mechanics, which offer new perspectives to understand the physics of living systems.
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Affiliation(s)
- F S Gnesotto
- Arnold-Sommerfeld-Center for Theoretical Physics and Center for NanoScience, Ludwig-Maximilians-Universität München, D-80333 München, Germany
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44
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Teuliere J, Kovacevic I, Bao Z, Garriga G. The Caenorhabditis elegans gene ham-1 regulates daughter cell size asymmetry primarily in divisions that produce a small anterior daughter cell. PLoS One 2018; 13:e0195855. [PMID: 29668718 PMCID: PMC5905977 DOI: 10.1371/journal.pone.0195855] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Accepted: 03/31/2018] [Indexed: 11/30/2022] Open
Abstract
C. elegans cell divisions that produce an apoptotic daughter cell exhibit Daughter Cell Size Asymmetry (DCSA), producing a larger surviving daughter cell and a smaller daughter cell fated to die. Genetic screens for mutants with defects in apoptosis identified several genes that are also required for the ability of these divisions to produce daughter cells that differ in size. One of these genes, ham-1, encodes a putative transcription factor that regulates a subset of the asymmetric cell divisions that produce an apoptotic daughter cell. In a survey of C. elegans divisions, we found that ham-1 mutations affect primarily anterior/posterior divisions that produce a small anterior daughter cell. The affected divisions include those that generate an apoptotic cell as well as those that generate two surviving cells. Our findings suggest that HAM-1 primarily promotes DCSA in a certain class of asymmetric divisions.
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Affiliation(s)
- Jerome Teuliere
- Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, California, United States of America
| | - Ismar Kovacevic
- Developmental Biology Program, Sloan Kettering Institute, New York City, New York, United States of America
| | - Zhirong Bao
- Developmental Biology Program, Sloan Kettering Institute, New York City, New York, United States of America
| | - Gian Garriga
- Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, California, United States of America
- * E-mail:
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45
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Koe CT, Tan YS, Lönnfors M, Hur SK, Low CSL, Zhang Y, Kanchanawong P, Bankaitis VA, Wang H. Vibrator and PI4KIIIα govern neuroblast polarity by anchoring non-muscle myosin II. eLife 2018; 7:33555. [PMID: 29482721 PMCID: PMC5828666 DOI: 10.7554/elife.33555] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Accepted: 01/26/2018] [Indexed: 12/19/2022] Open
Abstract
A central feature of most stem cells is the ability to self-renew and undergo differentiation via asymmetric division. However, during asymmetric division the role of phosphatidylinositol (PI) lipids and their regulators is not well established. Here, we show that the sole type I PI transfer protein, Vibrator, controls asymmetric division of Drosophilaneural stem cells (NSCs) by physically anchoring myosin II regulatory light chain, Sqh, to the NSC cortex. Depletion of vib or disruption of its lipid binding and transfer activities disrupts NSC polarity. We propose that Vib stimulates PI4KIIIα to promote synthesis of a plasma membrane pool of phosphatidylinositol 4-phosphate [PI(4)P] that, in turn, binds and anchors myosin to the NSC cortex. Remarkably, Sqh also binds to PI(4)P in vitro and both Vib and Sqh mediate plasma membrane localization of PI(4)P in NSCs. Thus, reciprocal regulation between Myosin and PI(4)P likely governs asymmetric division of NSCs. Stem cells are cells that can both make copies of themselves and make new cells of various types. They can either divide symmetrically to produce two identical new cells, or they can divide asymmetrically to produce two different cells. Asymmetric division happens because the two new cells contain different molecules. Stem cells drive asymmetric division by moving key molecules to one end of the cell before they divide. Asymmetric division is key to how neural stem cells produce new brain cells. Many studies have used the developing brain of the fruit fly Drosophila melanogaster to understand this process. Errors in asymmetric division can lead to too many stem cells or not enough brain cells. This can contribute to brain tumors and other neurological disorders. Fat molecules called phosphatidylinositol lipids are some of chemicals that cause asymmetry in neural stem cells. Yet, it is not clear how these lipid molecules affect cell behavior to turn stem cells into brain cells. The production of phosphatidylinositol lipids involves proteins called Vibrator and PI4KIIIα. Koe et al. examined the role of these two proteins in asymmetric cell division of neural stem cells in fruit flies. The results show that Vibrator activates PI4KIIIα, which leads to high levels of a phosphatidylinositol lipid called PI(4)P within the cell. These lipids act as an anchor for a group of proteins called myosin, part of the machinery that physically divides the cell. Hence, myosin and phosphatidylinositol lipids together control asymmetric division of neural stem cells. Further experiments used mouse proteins to compensate for defects in the equivalent fly proteins. The results suggest that the same mechanisms are likely to hold true in mammalian brains, although this still needs to be proven. Nevertheless, given that human equivalents of Vibrator and PI4KIIIα are associated with neurodegenerative disorders, schizophrenia or cancers, these new findings are likely to help scientists better to understand several human diseases.
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Affiliation(s)
- Chwee Tat Koe
- Neuroscience and Behavioral Disorders Programme, Duke-NUS Medical School, Singapore, Singapore
| | - Ye Sing Tan
- Neuroscience and Behavioral Disorders Programme, Duke-NUS Medical School, Singapore, Singapore
| | - Max Lönnfors
- Department of Molecular and Cellular Medicine, Texas A&M University Health Science Center, College Station, United States
| | - Seong Kwon Hur
- Department of Molecular and Cellular Medicine, Texas A&M University Health Science Center, College Station, United States
| | | | - Yingjie Zhang
- Neuroscience and Behavioral Disorders Programme, Duke-NUS Medical School, Singapore, Singapore.,NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore, Singapore, Singapore
| | - Pakorn Kanchanawong
- Mechanobiology Institute, National University of Singapore, Singapore, Singapore.,Department of Biomedical Engineering, National University of Singapore, Singapore, Singapore
| | - Vytas A Bankaitis
- Department of Molecular and Cellular Medicine, Texas A&M University Health Science Center, College Station, United States
| | - Hongyan Wang
- Neuroscience and Behavioral Disorders Programme, Duke-NUS Medical School, Singapore, Singapore.,NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore, Singapore, Singapore.,Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
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46
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Roubinet C, Tsankova A, Pham TT, Monnard A, Caussinus E, Affolter M, Cabernard C. Spatio-temporally separated cortical flows and spindle geometry establish physical asymmetry in fly neural stem cells. Nat Commun 2017; 8:1383. [PMID: 29123099 PMCID: PMC5680339 DOI: 10.1038/s41467-017-01391-w] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Accepted: 09/04/2017] [Indexed: 01/09/2023] Open
Abstract
Asymmetric cell division, creating sibling cells with distinct developmental potentials, can be manifested in sibling cell size asymmetry. This form of physical asymmetry occurs in several metazoan cells, but the underlying mechanisms and function are incompletely understood. Here we use Drosophila neural stem cells to elucidate the mechanisms involved in physical asymmetry establishment. We show that Myosin relocalizes to the cleavage furrow via two distinct cortical Myosin flows: at anaphase onset, a polarity induced, basally directed Myosin flow clears Myosin from the apical cortex. Subsequently, mitotic spindle cues establish a Myosin gradient at the lateral neuroblast cortex, necessary to trigger an apically directed flow, removing Actomyosin from the basal cortex. On the basis of the data presented here, we propose that spatiotemporally controlled Myosin flows in conjunction with spindle positioning and spindle asymmetry are key determinants for correct cleavage furrow placement and cortical expansion, thereby establishing physical asymmetry.
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Affiliation(s)
- Chantal Roubinet
- Biozentrum, University of Basel, Klingelbergstrasse 50-70, CH-4056, Basel, Switzerland
- MRC Laboratory for Molecular Cell Biology, University College London, Gower Street, London, WC1E 6BT, UK
| | - Anna Tsankova
- Biozentrum, University of Basel, Klingelbergstrasse 50-70, CH-4056, Basel, Switzerland
- Streuli Pharma AG, Bahnhofstrasse 7, CH-8730, Uznach, Switzerland
| | - Tri Thanh Pham
- Biozentrum, University of Basel, Klingelbergstrasse 50-70, CH-4056, Basel, Switzerland
- Department of Biology, University of Washington, 24 Kincaid Hall, Seattle, WA, 98195, USA
| | - Arnaud Monnard
- Biozentrum, University of Basel, Klingelbergstrasse 50-70, CH-4056, Basel, Switzerland
- Department of Biology, University of Washington, 24 Kincaid Hall, Seattle, WA, 98195, USA
| | - Emmanuel Caussinus
- Biozentrum, University of Basel, Klingelbergstrasse 50-70, CH-4056, Basel, Switzerland
- Institute of Molecular Life Sciences, University of Zurich, Winterthurerstrasse 190, CH-8057, Zurich, Switzerland
| | - Markus Affolter
- Biozentrum, University of Basel, Klingelbergstrasse 50-70, CH-4056, Basel, Switzerland
| | - Clemens Cabernard
- Biozentrum, University of Basel, Klingelbergstrasse 50-70, CH-4056, Basel, Switzerland.
- Department of Biology, University of Washington, 24 Kincaid Hall, Seattle, WA, 98195, USA.
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47
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Winter ES, Schwarz A, Fabig G, Feldman JL, Pires-daSilva A, Müller-Reichert T, Sadler PL, Shakes DC. Cytoskeletal variations in an asymmetric cell division support diversity in nematode sperm size and sex ratios. Development 2017; 144:3253-3263. [PMID: 28827395 DOI: 10.1242/dev.153841] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Accepted: 08/14/2017] [Indexed: 12/18/2022]
Abstract
Asymmetric partitioning is an essential component of many developmental processes. As spermatogenesis concludes, sperm are streamlined by discarding unnecessary cellular components into cellular wastebags called residual bodies (RBs). During nematode spermatogenesis, this asymmetric partitioning event occurs shortly after anaphase II, and both microtubules and actin partition into a central RB. Here, we use fluorescence and transmission electron microscopy to elucidate and compare the intermediate steps of RB formation in Caenorhabditis elegans, Rhabditis sp. SB347 (recently named Auanema rhodensis) and related nematodes. In all cases, intact microtubules reorganize and move from centrosomal to non-centrosomal sites at the RB-sperm boundary whereas actin reorganizes through cortical ring expansion and clearance from the poles. However, in species with tiny spermatocytes, these cytoskeletal changes are restricted to one pole. Consequently, partitioning yields one functional sperm with the X-bearing chromosome complement and an RB with the other chromosome set. Unipolar partitioning may not require an unpaired X, as it also occurs in XX spermatocytes. Instead, constraints related to spermatocyte downsizing may have contributed to the evolution of a sperm cell equivalent to female polar bodies.
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Affiliation(s)
- Ethan S Winter
- Department of Biology, College of William and Mary, Williamsburg, VA 23187, USA
| | - Anna Schwarz
- Experimental Center, Medical Faculty Carl Gustav Carus, Technische Universität Dresden, Dresden, 01307, Germany
| | - Gunar Fabig
- Experimental Center, Medical Faculty Carl Gustav Carus, Technische Universität Dresden, Dresden, 01307, Germany
| | - Jessica L Feldman
- Department of Biology, Stanford University, Stanford, CA, 94305, USA
| | | | - Thomas Müller-Reichert
- Experimental Center, Medical Faculty Carl Gustav Carus, Technische Universität Dresden, Dresden, 01307, Germany
| | - Penny L Sadler
- Department of Biology, College of William and Mary, Williamsburg, VA 23187, USA.,Department of Biology & Biochemistry, University of Houston, Houston, TX, 77204, USA
| | - Diane C Shakes
- Department of Biology, College of William and Mary, Williamsburg, VA 23187, USA
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48
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Li W, Yi P, Zhu Z, Zhang X, Li W, Ou G. Centriole translocation and degeneration during ciliogenesis in Caenorhabditis elegans neurons. EMBO J 2017; 36:2553-2566. [PMID: 28743734 DOI: 10.15252/embj.201796883] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Revised: 06/06/2017] [Accepted: 07/03/2017] [Indexed: 11/09/2022] Open
Abstract
Neuronal cilia that are formed at the dendritic endings of sensory neurons are essential for sensory perception. However, it remains unclear how the centriole-derived basal body is positioned to form a template for cilium formation. Using fluorescence time-lapse microscopy, we show that the centriole translocates from the cell body to the dendrite tip in the Caenorhabditis elegans sensory neurons. The centriolar protein SAS-5 interacts with the dynein light-chain LC8 and conditional mutations of cytoplasmic dynein-1 block centriole translocation and ciliogenesis. The components of the central tube are essential for the biogenesis of centrioles, which later drive ciliogenesis in the dendrite; however, the centriole loses these components at the late stage of centriole translocation and subsequently recruits transition zone and intraflagellar transport proteins. Together, our results provide a comprehensive model of ciliogenesis in sensory neurons and reveal the importance of the dynein-dependent centriole translocation in this process.
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Affiliation(s)
- Wenjing Li
- Tsinghua-Peking Center for Life Sciences, School of Life Sciences and MOE Key Laboratory for Protein Science, Tsinghua University, Beijing, China
| | - Peishan Yi
- Tsinghua-Peking Center for Life Sciences, School of Life Sciences and MOE Key Laboratory for Protein Science, Tsinghua University, Beijing, China
| | - Zhiwen Zhu
- Tsinghua-Peking Center for Life Sciences, School of Life Sciences and MOE Key Laboratory for Protein Science, Tsinghua University, Beijing, China
| | - Xianliang Zhang
- Tsinghua-Peking Center for Life Sciences, School of Life Sciences and MOE Key Laboratory for Protein Science, Tsinghua University, Beijing, China
| | - Wei Li
- Tsinghua-Peking Center for Life Sciences, School of Life Sciences and MOE Key Laboratory for Protein Science, Tsinghua University, Beijing, China
| | - Guangshuo Ou
- Tsinghua-Peking Center for Life Sciences, School of Life Sciences and MOE Key Laboratory for Protein Science, Tsinghua University, Beijing, China
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49
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Tsankova A, Pham TT, Garcia DS, Otte F, Cabernard C. Cell Polarity Regulates Biased Myosin Activity and Dynamics during Asymmetric Cell Division via Drosophila Rho Kinase and Protein Kinase N. Dev Cell 2017; 42:143-155.e5. [PMID: 28712722 DOI: 10.1016/j.devcel.2017.06.012] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Revised: 02/06/2017] [Accepted: 06/14/2017] [Indexed: 12/18/2022]
Abstract
Cell and tissue morphogenesis depends on the correct regulation of non-muscle Myosin II, but how this motor protein is spatiotemporally controlled is incompletely understood. Here, we show that in asymmetrically dividing Drosophila neural stem cells, cell intrinsic polarity cues provide spatial and temporal information to regulate biased Myosin activity. Using live cell imaging and a genetically encoded Myosin activity sensor, we found that Drosophila Rho kinase (Rok) enriches for activated Myosin on the neuroblast cortex prior to nuclear envelope breakdown (NEB). After NEB, the conserved polarity protein Partner of Inscuteable (Pins) sequentially enriches Rok and Protein Kinase N (Pkn) on the apical neuroblast cortex. Our data suggest that apical Rok first increases phospho-Myosin, followed by Pkn-mediated Myosin downregulation, possibly through Rok inhibition. We propose that polarity-induced spatiotemporal control of Rok and Pkn is important for unequal cortical expansion, ensuring correct cleavage furrow positioning and the establishment of physical asymmetry.
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Affiliation(s)
- Anna Tsankova
- Biozentrum, University of Basel, Klingelbergstrasse 50-70, 4056 Basel, Switzerland
| | - Tri Thanh Pham
- Biozentrum, University of Basel, Klingelbergstrasse 50-70, 4056 Basel, Switzerland; Department of Biology, University of Washington, 24 Kinkaid Hall, Seattle, WA 98105, USA
| | | | - Fabian Otte
- Biozentrum, University of Basel, Klingelbergstrasse 50-70, 4056 Basel, Switzerland
| | - Clemens Cabernard
- Biozentrum, University of Basel, Klingelbergstrasse 50-70, 4056 Basel, Switzerland; Department of Biology, University of Washington, 24 Kinkaid Hall, Seattle, WA 98105, USA.
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50
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Offenburger SL, Bensaddek D, Murillo AB, Lamond AI, Gartner A. Comparative genetic, proteomic and phosphoproteomic analysis of C. elegans embryos with a focus on ham-1/STOX and pig-1/MELK in dopaminergic neuron development. Sci Rep 2017; 7:4314. [PMID: 28659600 PMCID: PMC5489525 DOI: 10.1038/s41598-017-04375-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Accepted: 05/12/2017] [Indexed: 11/09/2022] Open
Abstract
Asymmetric cell divisions are required for cellular diversity and defects can lead to altered daughter cell fates and numbers. In a genetic screen for C. elegans mutants with defects in dopaminergic head neuron specification or differentiation, we isolated a new allele of the transcription factor HAM-1 [HSN (Hermaphrodite-Specific Neurons) Abnormal Migration]. Loss of both HAM-1 and its target, the kinase PIG-1 [PAR-1(I)-like Gene], leads to abnormal dopaminergic head neuron numbers. We identified discrete genetic relationships between ham-1, pig-1 and apoptosis pathway genes in dopaminergic head neurons. We used an unbiased, quantitative mass spectrometry-based proteomics approach to characterise direct and indirect protein targets and pathways that mediate the effects of PIG-1 kinase loss in C. elegans embryos. Proteins showing changes in either abundance, or phosphorylation levels, between wild-type and pig-1 mutant embryos are predominantly connected with processes including cell cycle, asymmetric cell division, apoptosis and actomyosin-regulation. Several of these proteins play important roles in C. elegans development. Our data provide an in-depth characterisation of the C. elegans wild-type embryo proteome and phosphoproteome and can be explored via the Encyclopedia of Proteome Dynamics (EPD) - an open access, searchable online database.
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Affiliation(s)
- Sarah-Lena Offenburger
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee, DD1 5EH, UK
| | - Dalila Bensaddek
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee, DD1 5EH, UK
| | - Alejandro Brenes Murillo
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee, DD1 5EH, UK
| | - Angus I Lamond
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee, DD1 5EH, UK
| | - Anton Gartner
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee, DD1 5EH, UK.
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