RRC ID 84059
Author Kohlbrenner T, Berger S, Laranjeira AC, Aegerter-Wilmsen T, Comi LF, deMello A, Hajnal A.
Title Actomyosin-mediated apical constriction promotes physiological germ cell death in C. elegans.
Journal PLoS Biol
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.
Volume 22(8)
Pages e3002775
Published 2024-8-1
DOI 10.1371/journal.pbio.3002775
PII PBIOLOGY-D-23-02213
PMID 39178318
PMC PMC11376560
MeSH Actomyosin* / metabolism Animals Apoptosis* Caenorhabditis elegans* / metabolism Caenorhabditis elegans* / physiology Caenorhabditis elegans Proteins* / genetics Caenorhabditis elegans Proteins* / metabolism Cell Differentiation Cell Size Germ Cells* / metabolism Oocytes / metabolism
Resource
C.elegans tm1458