Degradation of the G protein-coupled receptor kinase 2 by the proteasome pathway

J Biol Chem. 1998 Dec 25;273(52):35238-44. doi: 10.1074/jbc.273.52.35238.

Abstract

GRK2 is a ubiquitous member of the G protein-coupled receptor kinase (GRK) family and has been shown to play a key role in determining the desensitization and resensitization patterns of a variety of G protein-coupled receptors. In this report, we show that GRK2 is actively degraded by the proteasome proteolytic pathway, unveiling a new mechanism for the rapid regulation of its expression levels. Interestingly, activation of beta2-adrenergic receptors (beta2AR) markedly increases GRK2 ubiquitination and degradation through the proteasome pathway. In addition, blocking GRK2 degradation notably alters beta2AR signaling and internalization, consistent with a relevant physiological role for GRK2 proteasomal degradation. Activity-dependent modulation of GRK2 cellular levels emerges as an important mechanism for modulating the cellular response to agonists acting through G protein-coupled receptors.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell-Free System
  • Cyclic AMP-Dependent Protein Kinases / genetics
  • Cyclic AMP-Dependent Protein Kinases / metabolism*
  • Cysteine Endopeptidases / metabolism*
  • Endocytosis
  • Enzyme Stability
  • GTP-Binding Proteins / metabolism
  • Gene Expression Regulation, Enzymologic
  • Multienzyme Complexes / metabolism*
  • Peptide Fragments / metabolism
  • Proteasome Endopeptidase Complex
  • Receptors, Adrenergic, beta-2 / genetics
  • Receptors, Adrenergic, beta-2 / metabolism*
  • Recombinant Proteins / metabolism
  • Signal Transduction
  • Ubiquitins / metabolism
  • beta-Adrenergic Receptor Kinases

Substances

  • Multienzyme Complexes
  • Peptide Fragments
  • Receptors, Adrenergic, beta-2
  • Recombinant Proteins
  • Ubiquitins
  • Cyclic AMP-Dependent Protein Kinases
  • beta-Adrenergic Receptor Kinases
  • Cysteine Endopeptidases
  • Proteasome Endopeptidase Complex
  • GTP-Binding Proteins