II型肌球蛋白调节轻链可解除肌球蛋白重链功能的自身抑制。

Type II myosin regulatory light chain relieves auto-inhibition of myosin-heavy-chain function.

作者信息

Naqvi N I, Wong K C, Tang X, Balasubramanian M K

机构信息

Cell Division Laboratory, Institute of Molecular Agrobiology, The National University of Singapore, 1 Research Link, Singapore 117604.

出版信息

Nat Cell Biol. 2000 Nov;2(11):855-8. doi: 10.1038/35041107.

DOI:10.1038/35041107

PMID:11056543

Abstract

The F-actin based motor protein myosin II has a key role in cytokinesis. Here we show that the Schizosaccharomyces pombe regulatory light chain (RLC) protein Rlc1p binds to Myo2p in manner that is dependent on the IQ sequence motif (the RLC-binding site), and that Rlc1p is a component of the actomyosin ring. Rlc1p is important for cytokinesis at all growth temperatures and is essential for this process at lower temperatures. Interestingly, all deleterious phenotypes associated with the loss of Rlc1p function are suppressed by deletion of the RLC binding site on Myo2p. We conclude that the sole essential function of RLCs in fission yeast is to relieve the auto-inhibition of myosin II function, which is mediated by the RLC-binding site, on the myosin heavy chain (MHC).

摘要

基于F-肌动蛋白的马达蛋白肌球蛋白II在胞质分裂中起关键作用。我们在此表明，裂殖酵母调节性轻链（RLC）蛋白Rlc1p以依赖于IQ序列基序（RLC结合位点）的方式与Myo2p结合，并且Rlc1p是肌动球蛋白环的一个组成部分。Rlc1p在所有生长温度下对胞质分裂都很重要，而在较低温度下该过程中它是必不可少的。有趣的是，与Rlc1p功能丧失相关的所有有害表型都通过缺失Myo2p上的RLC结合位点而得到抑制。我们得出结论，RLC在裂殖酵母中的唯一基本功能是解除由RLC结合位点介导的肌球蛋白II功能对肌球蛋白重链（MHC）的自身抑制。