Molecular brightness analysis reveals phosphatidylinositol 4-Kinase IIβ association with clathrin-coated vesicles in living cells.

ABSTRACT: Mammalian cells express two classes of phosphatidylinositol 4-kinase (PI4K), designated as Types II and III, that phosphorylate phosphatidylinositol to generate PI4P. A number of studies have indicated that these enzymes are important for Golgi trafficking and both early and late stages of endocytosis. In this study, we focus on PI4KIIβ, a protein that is evenly distributed between membrane and soluble fractions, and is believed to participate in stimulus-dependent phosphoinositide signaling. Using molecular brightness analysis, we found that EGFP-tagged PI4KIIβ exists as two distinct species in the cytoplasm: a soluble monomer and a high-order complex enriched with multiple copies of PI4KIIβ. This observation was confirmed by an autocorrelation analysis that identified two species with di

SUBMITTER: Li J 

PROVIDER: S-EPMC3475384 | biostudies-literature | 2012 Oct

REPOSITORIES: biostudies-literature