Isoform specific phosphorylation of protein phosphatase 2C expressed in COS7 cells

FEBS Letters

Yanagawa, Yuchio¹  Kusuda, Kazuyuki¹  Tamura, Shinri¹  Wang, Hong¹  Kobayashi, Takayasu¹  Hanada, Masahito¹  Ohnishi, Motoko¹  Ikeda, Shoko¹ 

[1] Department of Biochemistry, Institute of Development, Aging and Cancer, Tohoku University, 4-1 Seiryomachi, Aoba-ku, Sendai 980-8575, Japan

关键词: Protein phosphatase 2C;    Phosphorylation;    Site-directed mutagenesis;    Okadaic acid;   

DOI  :  10.1016/S0014-5793(98)00604-8

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Of the six distinct isoforms of mouse protein phosphatase 2C (PP2C) (α, β-1, β-2, β-3, β-4 and β-5), PP2Cα was specifically phosphorylated on the serine residue(s) when expressed in COS7 cells. Analysis of phosphorylation sites using site-directed mutagenesis demonstrated that Ser-375 and/or Ser-377 were phosphorylated in vivo. These serine residues were the sites of phosphorylation by casein kinase II in vitro. Phosphorylation of PP2Cα was enhanced two-fold by the addition of okadaic acid to the culture medium, but addition of cyclosporin A had no such effect. These results suggest that the expressed PP2Cα is phosphorylated by a casein kinase II-like protein kinase and dephosphorylated by PP1 and/or PP2A in COS7 cells.

【 授权许可】

Unknown