Redox signaling modulates Rho activity and tissue contractility in the C. elegans spermatheca

Kelley, C. A.; De Henau, S.; Bell, L.; Dansen, T. B.; Cram, E. J.

doi:10.1101/849463

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bioRxiv · 10.1101/849463

Redox signaling modulates Rho activity and tissue contractility in the C. elegans spermatheca

Kelley, C. A.·De Henau, S.·Bell, L.·Dansen, T. B.·Cram, E. J.

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Abstract

Actomyosin based contractility in smooth muscle and non-muscle cells is regulated by signaling through the small GTPase Rho and by calcium-activated pathways. We use the myoepithelial cells of the Caenorhabditis elegans spermatheca to study the mechanisms of coordinated myosin activation in vivo. Here, we demonstrate that redox signaling regulates RHO-1/Rho activity in this contractile tissue. Exogenous hydrogen peroxide treatment decreases spermathecal contractility by inhibiting RHO-1, which is mediated through a conserved cysteine in its active site (C20). Further, we identify a gradient of oxidation across the spermathecal tissue, which is regulated by the cytosolic superoxide dismutase, SOD-1. SOD-1 functions in the Rho pathway to inhibit RHO-1 through oxidation of C20. Our results suggest that SOD-1 functions to regulate the redox environment and to fine-tune Rho activity across the spermatheca.

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Kelley, C. A., De Henau, S., Bell, L., Dansen, T. B., Cram, E. J.. 2019-11-20. Redox signaling modulates Rho activity and tissue contractility in the C. elegans spermatheca. https://doi.org/10.1101/849463

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