Phosphorylation of vascular smooth muscle caldesmon by endogenous kinase

FEBS Letters

Pinter, Katalin¹  Marston, Steven B.¹ 

[1] Department of Cardiac Medicine, National Heart and Lung Institute, Dovehouse St., London SW3 6LY, UK

关键词: Caldesmon;    Phosphorylation;    Smooth muscle;    Regulation;    Actin;    Myosin;   

DOI  :  10.1016/0014-5793(92)80665-4

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Caldesmon was phosphorylated up to 1.2 molP_i/mol using a partially purified endogenous kinase fraction. The phosphorylation site was within the C-terminal 99 amino acids. We were also able to phosphorylate caldesmon incorporated into native and synthetic smooth muscle thin filaments. Phosphorylation did not alter caldesmon binding to actin or inhibition or actomyosin ATPase. It also did not change Ca²⁺ sensitivity in native thin filaments. Phosphorylated caldesmon bound to myosin less than unphosphorylated caldesmon, especially when the myosin was also not phosphorylated. This work did not support the hypothesis that caldesmon function is modulated by phosphorylation.

【 授权许可】

Unknown