Phosphorylation of the Na+,K+-ATPase in skeletal muscle: potential mechanism for changes in pump cell-surface abundance and activity.
In skeletal muscle, insulin stimulation leads to phosphorylation of Na(+),K(+)-ATPase alpha-subunits on both serine/threonine and tyrosine residues, translocation of Na(+),K(+)-ATPase molecules to the plasma membrane, and increased Na(+),K(+)-ATPase activity. The molecular nature of the tyrosine kinase that phosphorylates Na(+),K(+)-ATPase is not yet identified. In vitro phosphorylation experiments show that the alpha-subunit of Na(+),K(+)-ATPase from skeletal muscle is a substrate for the tyrosine-specific protein kinase c-src. Tyrosine phosphorylation of the alpha-subunits of Na(+),K(+)-ATPase may be an important mechanism for insulin-mediated regulation of Na(+),K(+)-ATPase translocation and activity.
Al-Khalili
Lubna
L
Department of Clinical Physiology, Karolinska Hospital, 171 76 Stockholm, Sweden.
Krook
Anna
A
Chibalin
Alexander V
AV
D000818:Animals; D002462:Cell Membrane / Q000201:enzymology*; D007700:Kinetics; D018482:Muscle, Skeletal / Q000201:enzymology*; D010766:Phosphorylation; D021122:Protein Subunits / Q000378:metabolism; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism*
D021122:Protein Subunits; D000254:Sodium-Potassium-Exchanging ATPase