Structure and function of Vps15 in the endosomal G protein signaling pathway.

ABSTRACT: G protein-coupled receptors mediate cellular responses to a wide variety of stimuli, including taste, light, and neurotransmitters. In the yeast Saccharomyces cerevisiae, activation of the pheromone pathway triggers events leading to mating. The view had long been held that the G protein-mediated signal occurs principally at the plasma membrane. Recently, it has been shown that the G protein alpha subunit Gpa1 can promote signaling at endosomes and requires two components of the sole phosphatidylinositol-3-kinase in yeast, Vps15 and Vps34. Vps15 contains multiple WD repeats and also binds to Gpa1 preferentially in the GDP-bound state; these observations led us to hypothesize that Vps15 may function as a G protein beta subunit at the endosome. Here we show an X-ray crystal structure of the

SUBMITTER: Heenan EJ 

PROVIDER: S-EPMC2740480 | biostudies-literature | 2009 Jul

REPOSITORIES: biostudies-literature