Vasodilator-stimulated phosphoprotein is a substrate for protein kinase C.
Vasodilator-stimulated phosphoprotein (VASP), an actin binding protein localized to areas of focal contacts, is a substrate for the cyclic adenosine monophosphate/cyclic guanosine monophosphate (cAMP/cGMP)-dependent protein kinases (PKA, PKG). In this study, we show that serum stimulation of vascular smooth muscle cells (SMCs) induces VASP phosphorylation on Ser157, in a mechanism not dependent on PKA or PKG. We tested the possibility that protein kinase C (PKC), a regulator of cytoskeletal function, is involved. PKC inhibition or down-regulation prevented serum-induced phosphorylation of VASP at Ser157 in rat vascular SMCs. Additionally, recombinant PKCalpha directly phosphorylated Ser157 on VASP. In summary, our data support the hypothesis that PKC phosphorylates VASP and mediates serum-induced VASP regulation.
Chitaley
K
K
Department of Surgery, University of Washington, Seattle, WA 98195, USA. kanchanc@u.washington.edu
Chen
L
L
Galler
A
A
Walter
U
U
Daum
G
G
Clowes
A W
AW
D000818:Animals; D001011:Aorta / Q000166:cytology; D002417:Cattle; D015815:Cell Adhesion Molecules / Q000235:genetics / Q000378:metabolism*; D017868:Cyclic AMP-Dependent Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005312:Fetal Blood; D007527:Isoenzymes; D008840:Microfilament Proteins; D009131:Muscle, Smooth, Vascular / Q000166:cytology; D032389:Myocytes, Smooth Muscle / Q000378:metabolism; D010750:Phosphoproteins / Q000235:genetics / Q000378:metabolism*; D010766:Phosphorylation; D011493:Protein Kinase C / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D051381:Rats; D011916:Rats, Inbred F344; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D012694:Serine / Q000378:metabolism; D044967:Serum / Q000502:physiology; D013379:Substrate Specificity; D000098662:Vasodilator-Stimulated Phosphoprotein
D015815:Cell Adhesion Molecules; D004791:Enzyme Inhibitors; D007527:Isoenzymes; D008840:Microfilament Proteins; D010750:Phosphoproteins; D011994:Recombinant Proteins; D000098662:Vasodilator-Stimulated Phosphoprotein; D012694:Serine; D017868:Cyclic AMP-Dependent Protein Kinases; D011493:Protein Kinase C