The Exo70 Subunit of the Exocyst Is an Effector for Both Cdc42 and Rho3 Function in Polarized Exocytosis

Genetic and biochemical evidence is presented that the Exo70 subunit of the exocyst is a direct effector for both Rho3 and Cdc42 GTPases in yeast. Prenylation of these GTPases both promotes the interaction and affects the site of binding within Exo70. Thus, interaction of the Rho GTPases with Exo70 is a key event in spatial regulation of exocytosis.

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