Role of phosphatidylinositol 3' kinase and a downstream pleckstrin homology domain-containing protein in controlling chemotaxis in dictyostelium.

ABSTRACT: We show that cells lacking two Dictyostelium class I phosphatidylinositol (PI) 3' kinases (PI3K and pi3k1/2-null cells) or wild-type cells treated with the PI3K inhibitor LY294002 are unable to properly polarize, are very defective in the temporal, spatial, and quantitative regulation of chemoattractant-mediated filamentous (F)-actin polymerization, and chemotax very slowly. PI3K is thought to produce membrane lipid-binding sites for localization of PH domain-containing proteins. We demonstrate that in response to chemoattractants three PH domain-containing proteins do not localize to the leading edge in pi3k1/2-null cells, and the translocation is blocked in wild-type cells by LY294002. Cells lacking one of these proteins, phdA-null cells, exhibit defects in the level and kinetics of acti

SUBMITTER: Funamoto S 

PROVIDER: S-EPMC2192389 | biostudies-literature | 2001 May

REPOSITORIES: biostudies-literature