Dephosphorylation of the focal adhesion protein VASP in vitro and in intact human platelets

FEBS Letters

Abel, Kathrin²  Mieskes, Gottfried¹  Walter, Ulrich² 

[1] Zentrum Innere Medizin, Abt. Klinische Biochemie, Robert-Koch-Str. 40, D-37075 Göttingen, Germany;Medizinische Universitätsklinik, Klinische Biochemie und Pathobiochemie, Josef-Schneider-Str. 2, D- 97080 Würzburg, Germany

关键词: Protein serine/threonine phosphatase;    Okadaic acid;    cAMP-/cGMP-dependent protein kinase;    cAK;    cAMP-dependent protein kinase;    cGK;    cGMP-dependent protein kinase;    OA;    okadaic acid;    PP1;    protein phosphatase type 1;    PP2A;    PP2B;    PP2C;    protein phosphatase type 2A;    2B and 2C;    Sp-5;    6-DCl-cBiMPS;    Sp-5;    6-dichloro-1-β-d-ribofuranosylbenzimidazole-3′;    5′-monophosphoro-thioate;    w/o;    without;   

DOI  :  10.1016/0014-5793(95)00817-S

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The focal adhesion protein VASP, a possible link between signal transduction pathways and the microfilament system, is phosphorylated by both cAMP- and cGMP-dependent protein kinases in vitro and in intact cells. Here, the analysis of VASP dephosphorylation by the serine/threonine protein phosphatases (PP) PP1, PP2A, PP2B and PP2C in vitro is reported. The phosphatases differed in their selectivity with respect to the dephosphorylation of individual VASP phosphorylation sites. Incubation of human platelets with okadaic acid, a potent inhibitor of PP1 and PP2A, caused the accumulation of phosphorylated VASP indicating that the phosphorylation status of VASP in intact cells is regulated to a major extent by serine/ threonine protein phosphatases. Furthermore, the accumulation of phosphorylated cAMP-dependent protein kinase substrate(s) appears to account for inhibitory effects of okadaic acid on platelet function.

【 授权许可】

Unknown