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bioRxiv · 10.1101/093252

The sek-1 p38 MAP kinase pathway regulates Gq signaling in C. elegans

Hoyt, J. M.·Wilson, S. K.·Kasa, M.·Rise, J. S.·Topalidou, I.·Ailion, M.
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Abstract

Gq is a heterotrimeric G protein that is widely expressed in neurons and regulates neuronal activity. To identify pathways regulating neuronal Gq signaling we performed a forward genetic screen in Caenorhabditis elegans for suppressors of activated Gq. One of the suppressors is an allele of sek-1, which encodes a mitogen-activated protein kinase kinase (MAPKK) in the p38 MAPK pathway. Here we show that sek-1 mutants have a slow locomotion rate and that sek-1 acts in acetylcholine neurons to modulate both locomotion rate and Gq signaling. Furthermore, we find that sek-1 acts in mature neurons to modulate locomotion. Using genetic and behavioral approaches we demonstrate that other components of the p38 MAPK pathway also play a positive role in modulating locomotion and Gq signaling. Finally, we find that mutants in the SEK-1 p38 MAPK pathway partially suppress an activated mutant of the sodium leak channel NCA-1/NALCN, a downstream target of Gq signaling. Our results suggest that the SEK-1 p38 pathway may modulate the output of Gq signaling through NCA-1.

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Hoyt, J. M., Wilson, S. K., Kasa, M., Rise, J. S., Topalidou, I., Ailion, M.. 2016-12-12. The sek-1 p38 MAP kinase pathway regulates Gq signaling in C. elegans. https://doi.org/10.1101/093252

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