Daxx functions as a scaffold of a protein assembly constituted by GLUT4, JNK1 and KIF5B

J Cell Physiol. 2009 Feb;218(2):416-26. doi: 10.1002/jcp.21614.

Abstract

We have previously reported the physical interaction between Daxx, the adaptor protein that mediates activation of the Jun amino-terminal kinase (JNK), and GLUT4, the insulin-dependent glucose transporter, interaction that involves their C-domains. Co-immunoprecipitation and two-hybrid-based protein-protein interaction studies show now that Daxx and GLUT4 interact with JNK1 through D-sites in their NH(2)-(aa 1-501) and large endofacial loop, respectively. Serum deprivation strongly enhances the association of JNK1 with Daxx and dissociates the kinase from GLUT4. SP600125, a potent JNK1 inhibitor, reduces the JNK1 activity associated with GLUT4 and the phosphorylation of two minor GLUT4 species in serum-starved 3T3-L1 adipocytes. In addition, Daxx interacts with kinesin KIF5B through the 6xTPR domain of the kinesin light chain, a domain engaged in the grab hold of protein cargo by kinesin motors that codistribute with JNK. Depletion of Daxx in 3T3-L1 adipocytes provokes the partial translocation of the GLUT4 retained in the GLUT4 storage compartment to endosomes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 3T3-L1 Cells
  • Adipocytes / drug effects
  • Adipocytes / enzymology
  • Animals
  • Anthracenes / pharmacology
  • Carrier Proteins / chemistry
  • Carrier Proteins / metabolism*
  • Co-Repressor Proteins
  • Glucose Transporter Type 4 / chemistry
  • Glucose Transporter Type 4 / metabolism*
  • Humans
  • Immunoprecipitation
  • Insulin Receptor Substrate Proteins / metabolism
  • Intracellular Signaling Peptides and Proteins / chemistry
  • Intracellular Signaling Peptides and Proteins / metabolism*
  • Kinesins / metabolism*
  • Mice
  • Microtubules / drug effects
  • Microtubules / metabolism
  • Mitogen-Activated Protein Kinase 8 / antagonists & inhibitors
  • Mitogen-Activated Protein Kinase 8 / chemistry
  • Mitogen-Activated Protein Kinase 8 / metabolism*
  • Molecular Chaperones
  • Nuclear Proteins / chemistry
  • Nuclear Proteins / metabolism*
  • Phosphorylation / drug effects
  • Protein Binding / drug effects
  • Protein Structure, Secondary
  • Protein Structure, Tertiary
  • Protein Transport / drug effects
  • Rats
  • Serum

Substances

  • Anthracenes
  • Carrier Proteins
  • Co-Repressor Proteins
  • Daxx protein, mouse
  • Glucose Transporter Type 4
  • Insulin Receptor Substrate Proteins
  • Intracellular Signaling Peptides and Proteins
  • Irs1 protein, mouse
  • Molecular Chaperones
  • Nuclear Proteins
  • pyrazolanthrone
  • Mitogen-Activated Protein Kinase 8
  • Kif5b protein, mouse
  • Kinesins