Atrial natriuretic factor stimulates phosphorylation of a 52-kDa calmodulin-binding protein in vascular smooth muscle cells.
The effect of atrial natriuretic factor (ANF) on the phosphorylation of the calmodulin-binding protein in vascular smooth muscle cells was investigated. Several phosphorylated calmodulin-binding proteins ranging in molecular weight from 205,000 to 50,000 were detected. Among them, we have found that the phosphorylation of a 52-kDa protein present mainly in the cytosolic fraction is stimulated by ANF and that the elevation of the phosphorylation is both time- and dose-dependent. Furthermore, the stimulation was mimicked by 8-bromo-cyclic GMP but not by 8-bromo-cyclic AMP. Endothelin induced significant inhibition of the phosphorylation. These results indicate that 52-kDa protein phosphorylation may be responsible for the regulation of vascular smooth muscle tone.
Nakajo
S
S
Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232.
Inagami
T
T
D000818:Animals; D001011:Aorta / Q000166:cytology / Q000378:metabolism*; D009320:Atrial Natriuretic Factor / Q000494:pharmacology*; D002148:Calmodulin-Binding Proteins / Q000378:metabolism*; D002478:Cells, Cultured; D006152:Cyclic GMP / Q000031:analogs & derivatives / Q000494:pharmacology; D003600:Cytosol / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D016232:Endothelins / Q000494:pharmacology; D008297:Male; D009131:Muscle, Smooth, Vascular / Q000187:drug effects / Q000378:metabolism*; D010766:Phosphorylation; D010768:Phosphoserine / Q000032:analysis; D010769:Phosphothreonine / Q000032:analysis; D019000:Phosphotyrosine; D011494:Protein Kinases / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D017208:Rats, Wistar; D014443:Tyrosine / Q000031:analogs & derivatives / Q000032:analysis
D002148:Calmodulin-Binding Proteins; D016232:Endothelins; D010769:Phosphothreonine; D010768:Phosphoserine; D019000:Phosphotyrosine; C016276:8-bromocyclic GMP; D014443:Tyrosine; D009320:Atrial Natriuretic Factor; D011494:Protein Kinases; D006152:Cyclic GMP