Vps41 phosphorylation and the Rab Ypt7 control the targeting of the HOPS complex to endosome-vacuole fusion sites.

ABSTRACT: Membrane fusion depends on multisubunit tethering factors such as the vacuolar HOPS complex. We previously showed that the vacuolar casein kinase Yck3 regulates vacuole biogenesis via phosphorylation of the HOPS subunit Vps41. Here, we link the identified Vps41 phosphorylation site to HOPS function at the endosome-vacuole fusion site. The nonphosphorylated Vps41 mutant (Vps41 S-A) accumulates together with other HOPS subunits on punctate structures proximal to the vacuole that expand in a class E mutant background and that correspond to in vivo fusion sites. Ultrastructural analysis of this mutant confirmed the presence of tubular endosomal structures close to the vacuole. In contrast, Vps41 with a phosphomimetic mutation (Vps41 S-D) is mislocalized and leads to multilobed vacuoles, indica

SUBMITTER: Cabrera M 

PROVIDER: S-EPMC2663929 | biostudies-literature | 2009 Apr

REPOSITORIES: biostudies-literature