Rac1/RhoA antagonism defines cell-to-cell heterogeneity during epidermal morphogenesis in nematodes.
The antagonism between the GTPases Rac1 and RhoA controls cell-to-cell heterogeneity in isogenic populations of cells in vitro and epithelial morphogenesis in vivo. Its involvement in the regulation of cell-to-cell heterogeneity during epidermal morphogenesis has, however, never been addressed. We used a quantitative cell imaging approach to characterize epidermal morphogenesis at a single-cell level during early elongation of Caenorhabditis elegans embryos. This study reveals that a Rac1-like pathway, involving the Rac/Cdc42 guanine-exchange factor β-PIX/PIX-1 and effector PAK1/PAK-1, and a RhoA-like pathway, involving ROCK/LET-502, control the remodeling of apical junctions and the formation of basolateral protrusions in distinct subsets of hypodermal cells. In these contexts, protrusions adopt lamellipodia or an amoeboid morphology. We propose that lamella formation may reduce tension building at cell-cell junctions during morphogenesis. Cell-autonomous antagonism between these pathways enables cells to switch between Rac1- and RhoA-like morphogenetic programs. This study identifies the first case of cell-to-cell heterogeneity controlled by Rac1/RhoA antagonism during epidermal morphogenesis.
Department of Chemistry, Pharmaqam, Université du Québec à Montréal, Montreal, QC H3C 3P8, Canada.
Emmanuel
http://orcid.org/0000-0003-3878-8633
E
Martin
Department of Chemistry, Pharmaqam, Université du Québec à Montréal, Montreal, QC H3C 3P8, Canada.
Marie-Hélène
MH
Ouellette
Department of Chemistry, Pharmaqam, Université du Québec à Montréal, Montreal, QC H3C 3P8, Canada jenna.sarah@uqam.ca.
Sarah
S
Jenna
D000818:Animals; D016880:Anisotropy; D017173:Caenorhabditis elegans / Q000166:cytology / Q000254:growth & development* / Q000378:metabolism; D029742:Caenorhabditis elegans Proteins / Q000378:metabolism*; D048430:Cell Shape; D000078404:Epidermal Cells; D004817:Epidermis / Q000254:growth & development* / Q000378:metabolism; D049452:Green Fluorescent Proteins / Q000378:metabolism; D007365:Intercellular Junctions / Q000378:metabolism; D008954:Models, Biological; D009024:Morphogenesis; D009154:Mutation / Q000235:genetics; D009218:Myosins / Q000378:metabolism; D011554:Pseudopodia / Q000378:metabolism; D020830:rac1 GTP-Binding Protein / Q000037:antagonists & inhibitors* / Q000378:metabolism; D020742:rhoA GTP-Binding Protein / Q000037:antagonists & inhibitors* / Q000378:metabolism
D029742:Caenorhabditis elegans Proteins; D049452:Green Fluorescent Proteins; D009218:Myosins; D020830:rac1 GTP-Binding Protein; D020742:rhoA GTP-Binding Protein