Phosphorylation of H,K-ATPase alpha-subunit in microsomes from rabbit gastric mucosa by cAMP-dependent protein kinase

Biosci Rep. 1999 Apr;19(2):109-14. doi: 10.1023/a:1020110510609.

Abstract

A 100-kDa protein that is a main component of the microsomal fraction from rabbit gastric mucosa is phosphorylated by cAMP-dependent protein kinase (PKA) in the presence of 0.2% Triton X-100. Microsomes from rabbit gastric mucosa possess activity of H,K-ATPase but not activity of Na,K-ATPase. Incubation of microsomes with 5 microM fluorescein 5'-isothiocyanate (FITC) results in both an inhibition of H,K-ATPase and labeling of a protein with an electrophoretic mobility corresponding to the mobility of the protein phosphorylated by PKA. The data suggest that the alpha-subunit of H,K-ATPase can be a potential target for PKA phosphorylation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cyclic AMP-Dependent Protein Kinases / metabolism*
  • Enzyme Inhibitors / pharmacology
  • Fluorescein-5-isothiocyanate / metabolism
  • Fluorescent Dyes / metabolism
  • Gastric Mucosa / metabolism*
  • H(+)-K(+)-Exchanging ATPase / chemistry
  • H(+)-K(+)-Exchanging ATPase / metabolism*
  • Microsomes / metabolism*
  • Phosphorus Radioisotopes
  • Phosphorylation
  • Potassium Chloride / pharmacology
  • Proton Pump Inhibitors
  • Rabbits
  • Sodium Chloride / pharmacology

Substances

  • Enzyme Inhibitors
  • Fluorescent Dyes
  • Phosphorus Radioisotopes
  • Proton Pump Inhibitors
  • Sodium Chloride
  • Potassium Chloride
  • Cyclic AMP-Dependent Protein Kinases
  • H(+)-K(+)-Exchanging ATPase
  • Fluorescein-5-isothiocyanate