Osh4p is needed to reduce the level of phosphatidylinositol-4-phosphate on secretory vesicles as they mature.

ABSTRACT: Phosphatidylinositol-4-phosphate (PI4P) is produced on both the Golgi and the plasma membrane. Despite extensive vesicular traffic between these compartments, genetic analysis suggests that the two pools of PI4P do not efficiently mix with one another. Several lines of evidence indicate that the PI4P produced on the Golgi is normally incorporated into secretory vesicles, but the fate of that pool has been unclear. We show here that in yeast the oxysterol-binding proteins Osh1-Osh7 are collectively needed to maintain the normal distribution of PI4P and that Osh4p is critical in this function. Osh4p associates with secretory vesicles at least in part through its interaction with PI4P and is needed, together with lipid phosphatases, to reduce the level of PI4P as vesicles approach sites of ex

SUBMITTER: Ling Y 

PROVIDER: S-EPMC4214785 | biostudies-literature | 2014 Nov

REPOSITORIES: biostudies-literature