Vasoactive intestinal polypeptide type-1 receptor regulation. Desensitization, phosphorylation, and sequestration.

Abstract

The vasoactive intestinal polypeptide type-1 (VPAC(1)) receptor is a class II G protein-coupled receptor, distinct from the adrenergic receptor superfamily. The mechanisms involved in the regulation of the VPAC(1) receptor are largely unknown. We examined agonist-dependent VPAC(1) receptor signaling, phosphorylation, desensitization, and sequestration in human embryonic kidney 293 cells. Agonist stimulation of cells overexpressing this receptor led to a dose-dependent increase in cAMP that peaked within 5-10 min and was completely desensitized after 20 min. Cells cotransfected with the VPAC(1) receptor (VPAC(1)R) and G protein-coupled receptor kinases (GRKs) 2, 3, 5, and 6 exhibited enhanced desensitization that was not evident with GRK 4. Immunoprecipitation of the epitope-tagged VPAC(1) receptor revealed dose-dependent phosphorylation that was increased with cotransfection of any GRK. Agonist-stimulated internalization of the VPAC(1)R peaked in 10 min, and neither overexpressed beta-arrestin nor its dominant-negative mutant altered internalization. However, a dynamin-dominant negative mutant did inhibit VPAC(1) receptor internalization. Interestingly, VPAC(1)R specificity in desensitization was not evident by study of the overexpressed receptor; however, we determined that human embryonic kidney 293 cells express an endogenous VPAC(1)R that did demonstrate dose-dependent GRK specificity. Therefore, VPAC(1) receptor regulation involves agonist-stimulated, GRK-mediated phosphorylation, beta-arrestin translocation, and dynamin-dependent receptor internalization. Moreover, study of endogenously expressed receptors may provide information not evident in overexpressed systems.

Statistics

050100150'04'06'08'10'12'14'16
Citations per Year

256 Citations

Semantic Scholar estimates that this publication has 256 citations based on the available data.

See our FAQ for additional information.

Cite this paper

@article{Shetzline2002VasoactiveIP, title={Vasoactive intestinal polypeptide type-1 receptor regulation. Desensitization, phosphorylation, and sequestration.}, author={Michael A. Shetzline and Julia K. L. Walker and Kenneth J. Valenzano and Richard T. Premont}, journal={The Journal of biological chemistry}, year={2002}, volume={277 28}, pages={25519-26} }