Stress-dependent inhibition of polarized cell growth through unbalancing the GEF/GAP regulation of Cdc42

Cdc42 GTPase rules cell polarity and growth in fission yeast. It is negatively and positively regulated by GTPase-activating proteins (GAPs) and guanine nucleotide exchange factors (GEFs), respectively. Active Cdc42-GTP localizes to the poles, where it associates with numerous proteins constituting...

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Detalles Bibliográficos
Autores: Salat Canela, Clàudia, 1989-, Carmona, Mercè, Martín-García, Rebeca, Pérez, Pilar, Ayté del Olmo, José, Hidalgo Hernando, Elena
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2021
País:España
Institución:Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya)
Repositorio:Recercat. Dipósit de la Recerca de Catalunya
OAI Identifier:oai:recercat.cat:10230/52247
Acceso en línea:http://hdl.handle.net/10230/52247
http://dx.doi.org/10.1016/j.celrep.2021.109951
Access Level:acceso abierto
Palabra clave:Cdc42
GAP
GEF
Rga3
Rga6
Scd1
Sty1
Cell polarity
Cell size
Stress response
Descripción
Sumario:Cdc42 GTPase rules cell polarity and growth in fission yeast. It is negatively and positively regulated by GTPase-activating proteins (GAPs) and guanine nucleotide exchange factors (GEFs), respectively. Active Cdc42-GTP localizes to the poles, where it associates with numerous proteins constituting the polarity module. However, little is known about its downregulation. We describe here that oxidative stress causes Sty1-kinase-dependent Cdc42 inactivation at cell poles. Both the amount of active Cdc42 at tips and cell length inversely correlate with Sty1 activity, explaining the elongated morphology of Δsty1 cells. We have created stress-blinded cell poles either by eliminating two Cdc42 GAPs or through the constitutive tethering of Gef1 to cell tips, and we biochemically demonstrate that the GAPs Rga3/6 and the GEF Gef1 are direct substrates of Sty1. We propose that phosphorylation of Rga3/6 and Gef1 mediates the Sty1-dependent inhibition of Cdc42 at cell tips, halting polarized growth during stress adaptation.