Phosphorylation of myosin-II regulatory light chain by cyclin-p34cdc2: a mechanism for the timing of cytokinesis.
Phosphorylation of myosin-II regulatory light chain by cyclin-p34cdc2: a mechanism for the timing of cytokinesis.
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DOI：
10.1083/jcb.118.3.595
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发表时间：
1992-08
期刊：
影响因子：
--
通讯作者：
Pollard TD
中科院分区：
文献类型：
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作者：
Satterwhite LL;Lohka MJ;Wilson KL;Scherson TY;Cisek LJ;Corden JL;Pollard TD
为了了解有丝分裂期间如何调节胞质分裂，我们测试了 cyclin-p34cdc2 的肌球蛋白-II 激酶活性，并研究了非洲爪蟾卵裂解物中肌球蛋白-II 的有丝分裂特异性磷酸化。纯化的细胞周期蛋白-p34cdc2 在体外磷酸化细胞质和平滑肌肌球蛋白-II 的调节轻链丝氨酸-1 或丝氨酸-2 和苏氨酸-9，这些位点已知抑制平滑肌和非肌肉肌球蛋白的肌动蛋白激活的肌球蛋白 ATP 酶活性（Nishikawa, M.、J. R. Sellers、R. S. Adelstein 和 H. Hidaka. 1984。 J. 生物化学，259：8808-8814；Bengur，A. R.，A. E. 罗宾逊，E. R. 塞勒斯，1987 年。 29:2713-2720）。非洲爪蟾细胞质肌球蛋白-II 调节轻链的丝氨酸-1 或-2 在中期稳定的非洲爪蟾卵裂解物中也被磷酸化，但在分裂间期则不然。在前期和中期，cyclin-p34cdc2 对肌球蛋白-II 的抑制可以延迟胞质分裂，直到染色体分离开始，从而确定相对于有丝分裂早期事件的胞质分裂时间。
To understand how cytokinesis is regulated during mitosis, we tested cyclin-p34cdc2 for myosin-II kinase activity, and investigated the mitotic-specific phosphorylation of myosin-II in lysates of Xenopus eggs. Purified cyclin-p34cdc2 phosphorylated the regulatory light chain of cytoplasmic and smooth muscle myosin-II in vitro on serine-1 or serine-2 and threonine-9, sites known to inhibit the actin-activated myosin ATPase activity of smooth muscle and nonmuscle myosin (Nishikawa, M., J. R. Sellers, R. S. Adelstein, and H. Hidaka. 1984. J. Biol. Chem. 259:8808-8814; Bengur, A. R., A. E. Robinson, E. Appella, and J. R. Sellers. 1987. J. Biol. Chem. 262:7613-7617; Ikebe, M., and S. Reardon. 1990. Biochemistry. 29:2713-2720). Serine-1 or -2 of the regulatory light chain of Xenopus cytoplasmic myosin-II was also phosphorylated in Xenopus egg lysates stabilized in metaphase, but not in interphase. Inhibition of myosin-II by cyclin-p34cdc2 during prophase and metaphase could delay cytokinesis until chromosome segregation is initiated and thus determine the timing of cytokinesis relative to earlier events in mitosis.