G alpha(q) acts as an adaptor protein in protein kinase C zeta (PKCzeta)-mediated ERK5 activation by G protein-coupled receptors (GPCR). Academic Article uri icon

Overview

abstract

  • G(q)-coupled G protein-coupled receptors (GPCR) mediate the actions of a variety of messengers that are key regulators of different cellular functions. These receptors can regulate a highly interconnected network of biochemical routes that control the activity of several members of the mitogen-activated protein kinase (MAPK) family. The ERK5 MAPK has been shown to be activated by G(q)-coupled GPCR via unknown mechanisms. We find that the atypical protein kinase C (PKCzeta), previously reported to interact with the ERK5 activator MEK5 and to be involved in epidermal growth factor-mediated ERK5 stimulation, plays a crucial role in the activation of the ERK5 pathway by G(q)-coupled GPCR. Stimulation of ERK5 by G(q)-coupled GPCR is abolished upon pharmacological inhibition of PKCzeta as well as in embryonic fibroblasts obtained from PKCzeta-deficient mice. Both PKCzeta and MEK5 associate to G alpha(q) upon activation of GPCR, thus forming a ternary complex that seems essential for the activation of ERK5. These data put forward a novel function of G alpha(q) as a scaffold protein involved in the modulation of the ERK5 cascade by GPCR that could be relevant in G(q)-mediated physiological functions.

publication date

  • March 3, 2010

Research

keywords

  • GTP-Binding Protein alpha Subunits, Gq-G11
  • MAP Kinase Signaling System
  • Mitogen-Activated Protein Kinase 7
  • Multiprotein Complexes
  • Protein Kinase C
  • Receptors, G-Protein-Coupled

Identity

PubMed Central ID

  • PMC2859508

Scopus Document Identifier

  • 77951589180

Digital Object Identifier (DOI)

  • 10.1074/jbc.M109.098699

PubMed ID

  • 20200162

Additional Document Info

volume

  • 285

issue

  • 18