Real-time visualization of the cellular redistribution of G protein-coupled receptor kinase 2 and beta-arrestin 2 during homologous desensitization of the substance P receptor.

Published

Journal Article

The substance P receptor (SPR) is a G protein-coupled receptor (GPCR) that plays a key role in pain regulation. The SPR desensitizes in the continued presence of agonist, presumably via mechanisms that implicate G protein-coupled receptor kinases (GRKs) and beta-arrestins. The temporal relationship of these proposed biochemical events has never been established for any GPCR other than rhodopsin beyond the resolution provided by biochemical assays. We investigate the real-time activation and desensitization of the human SPR in live HEK293 cells using green fluorescent protein conjugates of protein kinase C, GRK2, and beta-arrestin 2. The translocation of protein kinase C betaII-green fluorescent protein to and from the plasma membrane in response to substance P indicates that the human SPR becomes activated within seconds of agonist exposure, and the response desensitizes within 30 s. This desensitization process coincides with a redistribution of GRK2 from the cytosol to the plasma membrane, followed by a robust redistribution of beta-arrestin 2 and a profound change in cell morphology that occurs after 1 min of SPR stimulation. These data establish a role for GRKs and beta-arrestins in homologous desensitization of the SPR and provide the first visual and temporal resolution of the sequence of events underlying homologous desensitization of a GPCR in living cells.

Full Text

Duke Authors

Cited Authors

  • Barak, LS; Warabi, K; Feng, X; Caron, MG; Kwatra, MM

Published Date

  • March 12, 1999

Published In

Volume / Issue

  • 274 / 11

Start / End Page

  • 7565 - 7569

PubMed ID

  • 10066824

Pubmed Central ID

  • 10066824

International Standard Serial Number (ISSN)

  • 0021-9258

Digital Object Identifier (DOI)

  • 10.1074/jbc.274.11.7565

Language

  • eng

Conference Location

  • United States