@article{2f837f881edb4e0d9fa827fed8ff5c9b,
title = "The initial expansion of the C. elegans syncytial germ line is coupled to incomplete primordial germ cell cytokinesis",
abstract = "The C. elegans germline is organized as a syncytium in which each germ cell possesses an intercellular bridge that is maintained by a stable actomyosin ring and connected to a common pool of cytoplasm, termed the rachis. How germ cells undergo cytokinesis while maintaining this syncytial architecture is not completely understood. Here, we use live imaging to characterize primordial germ cell (PGC) division in C. elegans first-stage larvae. We show that each PGC possesses a stable intercellular bridge that connects it to a common pool of cytoplasm, which we term the proto-rachis. We further show that the first PGC cytokinesis is incomplete and that the stabilized cytokinetic ring progressively moves towards the proto-rachis and eventually integrates with it. Our results support a model in which the initial expansion of the C. elegans syncytial germline occurs by incomplete cytokinesis, where one daughter germ cell inherits the actomyosin ring that was newly formed by stabilization of the cytokinetic ring, while the other inherits the pre-existing stable actomyosin ring. We propose that such a mechanism of iterative cytokinesis incompletion underpins C. elegans germline expansion and maintenance.",
keywords = "Actomyosin, C. elegans germline development, Incomplete cytokinesis, Primordial germ cells, Stable intercellular bridge, Syncytium expansion",
author = "Jack Bauer and Vincent Poupart and Eug{\'e}nie Goupil and Nguyen, {Ken C.Q.} and Hall, {David H.} and Labb{\'e}, {Jean Claude}",
note = "Funding Information: J.B. received scholarships from the Institute for Research in Immunology and Cancer and from the Universit{\'e} de Montr{\'e}al{\textquoteright}s Graduate Studies and Molecular Biology programs. This study was supported by the National Institutes of Health (OD 010943 to D.H.H.] and the Natural Science and Engineering Research Council of Canada (RGPIN-2018-04297 to J.-C.L.). Deposited in PMC for release after 12 months. Funding Information: We thank Bob Goldstein (UNC Chapel Hill), Erik Griffin (Dartmouth), Amy Maddox (UNC Chapel Hill), Karen Oegema (UC San Diego) and Esther Zanin (LMU M{\"u}nich) for strains and reagents, and Vincent Archambault, Abigail Gerhold and Greg FitzHarris for comments on the manuscript. We are also grateful to Christian Charbonneau of IRIC{\textquoteright}s Bio-imaging Facility for technical assistance, to Kelly Sears and Jeannie Mui at the McGill University Facility for Electron Microscopy Research for help with microscope operation, and to all members of the FitzHarris, Gerhold, Hickson and Labb{\'e} laboratories for helpful discussions. Some strains were provided by the CGC, which is funded by NIH Office of Research Infrastructure Programs (P40 OD010440). Funding Information: J.B. received scholarships from the Institute for Research in Immunology and Cancer and from the Universit? de Montr?al's Graduate Studies and Molecular Biology programs. This study was supported by the National Institutes of Health (OD 010943 to D.H.H.] and the Natural Science and Engineering Research Council of Canada (RGPIN-2018-04297 to J.-C.L.). Deposited in PMC for release after 12 months. Publisher Copyright: {\textcopyright} 2021. Published by The Company of Biologists Ltd",
year = "2021",
doi = "10.1242/DEV.199633",
language = "English (US)",
volume = "148",
journal = "Journal of Embryology and Experimental Morphology",
issn = "0950-1991",
publisher = "Company of Biologists Ltd",
number = "18",
}