Chicken gizzard: relation between calcium-activated phosphorylation and contraction.
Chicken gizzard: relation between calcium-activated phosphorylation and contraction.
复制标题
鸡肫：钙激活磷酸化与收缩的关系。
作者：
P. E. Hoar;W. Kerrick;P. Cassidy
在机械破坏的鸡砂囊纤维（无功能性肌膜）中，只有肌球蛋白的20，000-道尔顿轻链发生了大的钙和锶依赖性磷酸化变化。磷酸化密切对应的Ca 2+和Sr 2+激活的张力。腺苷5 '-O（3'-硫代三磷酸）仅在Ca 2+存在下诱导不可逆的Ca 2+不敏感的张力活化和20，000-道尔顿轻链的硫代磷酸化，并阻断来自[γ-32 P]腺苷三磷酸的32 P掺入肌球蛋白轻链。
Of the proteins in mechanically disrupted chicken gizzard fibers (no functional sarcolemma) only the 20,000-dalton light chains of myosin underwent large Ca2+-and Sr2+-dependent changes in phosphorylation. Phosphorylation closely corresponded with the Ca2+- and Sr2+-activated tensions. Adenosine 5'-O (3'-thiotriphosphate) only in the presence of Ca2+ induced irreversible Ca2+-insensitive activation of tension and thiophosphorylation of the 20,000-dalton light chains, and blocked incorporation of 32P from [gamma-32P]adenosine triphosphate into the myosin light chains.