ACTIVATION OF SMOOTH-MUSCLE CONTRACTION - RELATION BETWEEN MYOSIN PHOSPHORYLATION AND STIFFNESS
ACTIVATION OF SMOOTH-MUSCLE CONTRACTION - RELATION BETWEEN MYOSIN PHOSPHORYLATION AND STIFFNESS
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DOI：
10.1126/science.3754063
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发表时间：
1986-04-04
期刊：
影响因子：
56.9
通讯作者：
STULL, JT
中科院分区：
文献类型：
--
作者：
KAMM, KE;STULL, JT
收缩和肌球蛋白轻链磷酸化测定在电刺激气管平滑肌。力、硬度和轻链磷酸化的起始时间为500毫秒。肌球蛋白轻链以每秒1.1的伪一级速率从0.04摩尔磷酸/摩尔轻链磷酸化至0.80摩尔磷酸/摩尔轻链，没有证据表明存在有序或负协同过程。潜伏期后，刚度增加与磷酸化和增加更迅速地比等长力。激活过程中刚度和磷酸化之间的线性关系表明磷酸化后每个肌球蛋白头的独立附着。
Contraction and myosin light-chain phosphorylation were measured in electrically stimulated tracheal smooth muscle. Latencies for the onset of force, stiffness, and light-chain phosphorylation were 500 milliseconds. Myosin light chain was phosphorylated from 0.04 to 0.80 mole of phosphate per mole of light chain with a pseudo-first-order rate of 1.1 per second with no evidence of an ordered or negatively cooperative process. Following the period of latency, stiffness increased with phosphorylation and both increased more rapidly than isometric force. The linear relation between stiffness and phosphorylation during activation suggests independent attachment of each myosin head upon phosphorylation.