Na+,K+-ATPase trafficking in skeletal muscle: insulin stimulates translocation of both alpha 1- and alpha 2-subunit isoforms

FEBS Lett. 2003 Feb 11;536(1-3):198-202. doi: 10.1016/s0014-5793(03)00047-4.

Abstract

We determined insulin-stimulated Na(+),K(+)-ATPase isoform-specific translocation to the skeletal muscle plasma membrane. When rat muscle plasma membrane fractions were isolated by discontinuous sucrose gradients, insulin-stimulated translocation of alpha(2)- but not alpha(1)-subunits was detected. However, using cell surface biotinylation techniques, an insulin-induced membrane translocation of both alpha(1) and alpha(2)-subunits in rat epitrochlearis muscle and cultured human skeletal muscle cells was noted. Na(+),K(+)-ATPase alpha-subunit translocation was abolished by the phosphatidylinositol (PI) 3-kinase inhibitor wortmannin, as well as by the protein kinase C inhibitor GF109203X. Thus, insulin mediates Na(+),K(+)-ATPase alpha(1)- and alpha(2)-subunit translocation to the skeletal muscle plasma membrane via a PI 3-kinase-dependent mechanism.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Biotinylation
  • Cell Membrane / enzymology
  • Cells, Cultured
  • Humans
  • Insulin / pharmacology*
  • Isoenzymes / metabolism
  • Muscle, Skeletal / drug effects
  • Muscle, Skeletal / enzymology*
  • Phosphatidylinositol 3-Kinases / physiology
  • Protein Subunits
  • Protein Transport / drug effects
  • Rats
  • Rats, Wistar
  • Sodium-Potassium-Exchanging ATPase / chemistry
  • Sodium-Potassium-Exchanging ATPase / metabolism*

Substances

  • Insulin
  • Isoenzymes
  • Protein Subunits
  • Sodium-Potassium-Exchanging ATPase