p38 mitogen‐activated protein kinase dephosphorylation is regulated by protein phosphatase 2A in human platelets activated by collagen

FEBS Letters

Farndale, Richard W¹  Sundaresan, Pavithra¹ 

[1] Department of Biochemistry, University of Cambridge, Building 0, Downing Site, Cambridge CB2 1QW, UK

关键词: p38 mitogen-activated protein kinase;    Protein phosphatase 2A;    Collagen;    Collagen-related peptide;    αIIbβ3;    Dephosphorylation;    BSA;    bovine serum albumin;    CRP-XL;    cross-linked collagen-related peptide;    GCO(GPO)10GCOG (where O=hydroxyproline);    GpVI;    glycoprotein VI;    MAPK;    mitogen-activated protein kinase;    OA;    okadaic acid;    PAO;    phenylarsine oxide;    PP2A;    protein phosphatase 2A;    PTPase;    protein tyrosine phosphatase;   

DOI  :  10.1016/S0014-5793(02)03277-5

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Collagen and the cross-linked collagen-related peptide (CRP-XL) each induced platelet p38 mitogen-activated protein kinase (p38) phosphorylation after 2 min. Subsequent dephosphorylation occurred in platelets activated with collagen, but not with CRP-XL, demonstrating glycoprotein VI-independent regulation of p38. Okadaic acid and fostriecin, inhibitors specific for protein phosphatase 2A (PP2A), blocked p38 dephosphorylation, and PP2A co-immunoprecipitated with phospho-p38. In addition, use of phenylarsine oxide suggested that tyrosine phosphatases and PP2A may act in concert to dephosphorylate p38. Finally, regulation of p38 in collagen-stimulated Glanzmann's platelets was indistinguishable from that in normal platelets, showing that p38 regulation is independent of integrin αIIbβ3.

【 授权许可】

Unknown