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Afadin and Zyxin contribute to coupling between cell junctions and contracting actomyosin networks during apical constriction

ABSTRACT: One of the most common cell shape changes driving morphogenesis in diverse animals is the constriction of the apical surface. Apical constriction depends on contraction of an actomyosin network in the apical cell cortex, but such actomyosin networks have been shown to undergo continual, conveyor belt-like contractions even before the shrinking of an apical surface begins. This finding suggests that apical constriction is not necessarily triggered by the contraction of actomyosin networks, but rather by unidentified, temporally-regulated mechanical linking of actomyosin to the cell junctions. Here, we used C. elegans gastrulation as a model to identify proteins that contribute to such linkage. We found that α-catenin and β-catenin initially failed to move centripetally with contracting cortical actomyosin networks, suggesting that linkage is regulated between cadherin-catenin complexes and actomyosin. We used a proteomic approach to identify AFD-1/afadin and transcriptomics to identify ZYX-1/zyxin as contributors to C. elegans gastrulation. We found that a zyxin family of LIM domain proteins have transcripts that become enriched in multiple cells just before they undergo apical constriction. Using a new, semi-automated image analysis tool, we found that AFD-1/afadin and ZYX-1/zyxin both contribute to cell-cell junctions’ centripetal movement along contracting actomyosin networks. These results identify two key proteins as important for actomyosin networks to effectively pull cell-cell junctions inward during apical constriction. The transcriptional upregulation of zyxin/ZYX-1 in specific cells points to one way that developmental patterning spatiotemporally regulates cell biological mechanisms in vivo. Because afadin- and zyxin-family proteins contribute to membrane-cytoskeleton linkage in other systems, we anticipate that their roles in regulating apical constriction in this manner may be conserved.

ORGANISM(S): Caenorhabditis elegans

PROVIDER: GSE205061 | GEO | 2022/06/30

REPOSITORIES: GEO

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Afadin and Zyxin contribute to coupling between cell junctions and contracting actomyosin networks during apical constriction

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