Skripnikova E V, Gusev N B
Department of Biochemistry, School of Biology, Moscow State University, USSR.
FEBS Lett. 1989 Nov 6;257(2):380-2. doi: 10.1016/0014-5793(89)81577-7.
The interaction of caldesmon with certain Ca-binding proteins was investigated by means of electrophoresis under non-denaturating conditions. In the presence of Ca2+ calmodulin, troponin C and S-100 protein form a complex with caldesmon. No complex formation takes place in the absence of Ca2+. Lactalbumin and pike parvalbumin (pI4.2) do not interact with caldesmon independently of Ca-concentration. Both S-100 protein and calmodulin effectively inhibit phosphorylation of caldesmon by Ca-phospholipid-dependent protein kinase. At low ionic strength S-100 protein reverses the inhibitory action of caldesmon on the skeletal muscle acto-heavy meromyosin ATPase more effectively than calmodulin. It is supposed that in certain tissues and cell compartments the proteins belonging to the S-100 family are able to substitute for calmodulin in the caldesmon-dependent regulation of actin and myosin interaction.
在非变性条件下，通过电泳研究了钙调蛋白与某些钙结合蛋白的相互作用。在Ca2+存在的情况下，钙调蛋白、肌钙蛋白C和S-100蛋白与钙调蛋白形成复合物。在没有Ca2+的情况下不发生复合物形成。乳白蛋白和梭子鱼小清蛋白（等电点4.2）与钙调蛋白的相互作用与钙浓度无关。S-100蛋白和钙调蛋白均有效抑制钙磷脂依赖性蛋白激酶对钙调蛋白的磷酸化作用。在低离子强度下，S-100蛋白比钙调蛋白更有效地逆转钙调蛋白对骨骼肌肌动蛋白-重酶解肌球蛋白ATP酶的抑制作用。据推测，在某些组织和细胞区室中，属于S-100家族的蛋白质能够在钙调蛋白依赖性调节肌动蛋白和肌球蛋白相互作用中替代钙调蛋白。
