The Arf GAP AGAP2 interacts with β-arrestin2 and regulates β2-adrenergic receptor recycling and ERK activation

Biochem J. 2013 Jun 15;452(3):411-21. doi: 10.1042/BJ20121004.

Abstract

AGAP2 [Arf (ADP-ribosylation factor) GAP (GTPase-activating protein) with GTP-binding-protein-like, ankyrin repeat and PH (pleckstrin homology) domains] is a multidomain Arf GAP that was shown to promote the fast recycling of transferrin receptors. In the present study we tested the hypothesis that AGAP2 regulates the trafficking of β2-adrenergic receptors. We found that AGAP2 formed a complex with β-arrestin1 and β-arrestin2, proteins that are known to regulate β2-adrenergic receptor signalling and trafficking. AGAP2 co-localized with β-arrestin2 on the plasma membrane, and knockdown of AGAP2 expression reduced plasma membrane association of β-arrestin2 upon β2-adrenergic receptor activation. AGAP2 also co-localized with internalized β2-adrenergic receptors on endosomes, and overexpression of AGAP2 slowed accumulation of β2-adrenergic receptor in the perinuclear recycling endosomes. In contrast, knockdown of AGAP2 expression prevented the recycling of the β2-adrenergic receptor back to the plasma membrane. In addition, AGAP2 formed a complex with endogenous ERK (extracellular-signal-regulated kinase) and overexpression of AGAP2 potentiated ERK phosphorylation induced by β2-adrenergic receptors. Taken together, these results support the hypothesis that AGAP2 plays a role in the signalling and recycling of β2-adrenergic receptors.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Arrestins / metabolism*
  • Cell Line, Tumor
  • Enzyme Activation / genetics
  • Extracellular Signal-Regulated MAP Kinases / metabolism*
  • GTP-Binding Proteins / antagonists & inhibitors
  • GTP-Binding Proteins / metabolism*
  • GTP-Binding Proteins / physiology
  • GTPase-Activating Proteins / antagonists & inhibitors
  • GTPase-Activating Proteins / metabolism*
  • GTPase-Activating Proteins / physiology
  • Gene Knockdown Techniques
  • HEK293 Cells
  • Humans
  • Protein Binding / genetics
  • Protein Transport / genetics
  • Receptors, Adrenergic, beta-2 / biosynthesis
  • Receptors, Adrenergic, beta-2 / genetics
  • Receptors, Adrenergic, beta-2 / metabolism*
  • Signal Transduction / genetics
  • beta-Arrestins

Substances

  • Arrestins
  • GTPase-Activating Proteins
  • Receptors, Adrenergic, beta-2
  • beta-Arrestins
  • Extracellular Signal-Regulated MAP Kinases
  • AGAP2 protein, human
  • GTP-Binding Proteins