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bioRxiv · 10.1101/2021.10.03.462551

Actin capping protein regulates actomyosin contractility to maintain germline architecture in C. elegans

Ray, S.·Agarwal, P.·Zaidel-Bar, R.
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Abstract

Actin dynamics play an important role in the morphogenesis of cells and tissues, yet the control of actin filament growth takes place at the molecular level. A challenge in the field is to link the molecular function of actin regulators with their physiological function. Here, we report the in vivo role of the actin capping protein CAP-1 in the C. elegans germline. We show that CAP-1 is associated with actomyosin structures in the cortex and rachis, where it keeps the level of contractility in check. A 60% reduction in the level of CAP-1 leads to a 2-fold increase in F-actin and non-muscle myosin II and only a 30% increase in Arp2/3. CAP-1 depletion leads to severe structural defects in the syncytial germline and oocytes, which can be rescued by reducing myosin activity. Thus, we uncover a physiological role for actin capping protein in maintaining C. elegans fertility by regulating the level of actomyosin contractility.

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Ray, S., Agarwal, P., Zaidel-Bar, R.. 2021-10-03. Actin capping protein regulates actomyosin contractility to maintain germline architecture in C. elegans. https://doi.org/10.1101/2021.10.03.462551

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