Desensitization of G protein-coupled receptors involves phosphorylation of the receptors by G protein-coupled receptor kinases, such as the β-adrenergic receptor kinase (βARK). βARK activity depends upon its translocation from the cytoplasm to the membrane. The βγ subunits of G proteins bind to βARK and recruit the kinase to the membrane. The Gβγ binding domain is localized to a carboxyl terminal region of βARK but the βARK binding domain of Gβγ is not known. We used the yeast two-hybrid assay to characterize the interaction between Gβ and βARK. We demonstrate an interaction between the carboxyl terminus of βARK and Gβ2. The strength of this interaction is increased when the VP16 transactivation domain is placed on the carboxyl end of Gβ2, indicating that an accessible Gβ2 amino terminus is important for its interaction with βARK. In addition, we show that amino acids 1 to 145 of Gβ2 are sufficient for βARK binding.
|Original language||English (US)|
|Number of pages||5|
|Journal||Biochemical and Biophysical Research Communications|
|State||Published - Nov 17 1997|
ASJC Scopus subject areas
- Molecular Biology
- Cell Biology