Tsk/Itk and Btk are members of the pleckstrin-homology (PH) domain- containing tyrosine kinase family. The PH domain has been demonstrated to be able to interact with βγ subunits of heterotrimeric guanine nucleotide- binding proteins (G proteins) (G(βγ)) and phospholipids. Using cotransfection assays, we show here that the kinase activities of Tsk and Btk are stimulated by certain G(βγ), subunits. Furthermore, using an in vitro reconstitution assay with purified bovine brain G(βγ) subunits and the immunoprecipitated Tsk, we find that Tsk kinase activity is increased by G(βγ) subunits and another membrane factor(s). These results indicate that this family of tyrosine kinases could be an effector of heterotrimeric G proteins.
|Original language||English (US)|
|Number of pages||5|
|Journal||Proceedings of the National Academy of Sciences of the United States of America|
|State||Published - Sep 12 1995|
- pleckstrin-homology domain
- signal transduction
ASJC Scopus subject areas