GIPC interacts with the beta1-adrenergic receptor and regulates beta1-adrenergic receptor-mediated ERK activation.

Published

Journal Article

Beta1-adrenergic receptors, expressed at high levels in the human heart, have a carboxyl-terminal ESKV motif that can directly interact with PDZ domain-containing proteins. Using the beta1-adrenergic receptor carboxyl terminus as bait, we identified the novel beta1-adrenergic receptor-binding partner GIPC in a yeast two-hybrid screen of a human heart cDNA library. Here we demonstrate that the PDZ domain-containing protein, GIPC, co-immunoprecipitates with the beta1-adrenergic receptor in COS-7 cells. Essential for this interaction is the Ser residue of the beta1-adrenergic receptor carboxyl-terminal ESKV motif. Our data also demonstrate that beta1-adrenergic receptor stimulation activates the mitogen-activated protein kinase, ERK1/2. beta1-adrenergic receptor-mediated ERK1/2 activation was inhibited by pertussis toxin, implicating Gi, and was substantially decreased by the expression of GIPC. Expression of GIPC had no observable effect on beta1-adrenergic receptor sequestration or receptor-mediated cAMP accumulation. This GIPC effect was specific for the beta1-adrenergic receptor and was dependent on an intact PDZ binding motif. These data suggest that GIPC can regulate beta1-adrenergic receptor-stimulated, Gi-mediated, ERK activation while having no effect on receptor internalization or Gs-mediated cAMP signaling.

Full Text

Duke Authors

Cited Authors

  • Hu, LA; Chen, W; Martin, NP; Whalen, EJ; Premont, RT; Lefkowitz, RJ

Published Date

  • July 11, 2003

Published In

Volume / Issue

  • 278 / 28

Start / End Page

  • 26295 - 26301

PubMed ID

  • 12724327

Pubmed Central ID

  • 12724327

International Standard Serial Number (ISSN)

  • 0021-9258

Digital Object Identifier (DOI)

  • 10.1074/jbc.M212352200

Language

  • eng

Conference Location

  • United States