Aydt Ewald M, Wolff Gerhard, Morano Ingo
Revotar Biopharmaceuticals AG, Hennigsdorf, Germany.
J Struct Biol. 2007 Jul;159(1):158-63. doi: 10.1016/j.jsb.2007.04.002. Epub 2007 Apr 11.
Type II myosin is the molecular motor which drives contraction upon cyclic interaction with filamentous actin while consuming ATP. The contemporary crystallographic structure of the myosin subfragment-1 (S1) of myosin covers both the motor domain of the heavy chain (MHC) as well as the essential (ELC) and regulatory light chains (RLC). A part of the N-terminus of the ELC is, however, missing in the 3D-models of Type II myosin. The N-terminal domain of the ELC comprises interesting functional features since it binds to actin thus controlling myosin motor activity. For the first time, we modeled the missing 46 N-terminal amino acid of the ELC to the contemporary actin-myosin-S1 complex. We show a rod-like 91 A structure being long enough to bridge the gap between the ELC core of myosin-S1 and the appropriate binding site of the ELC on the actin filament.
II型肌球蛋白是一种分子马达，它在与丝状肌动蛋白循环相互作用并消耗三磷酸腺苷（ATP）时驱动收缩。肌球蛋白的肌球蛋白亚片段-1（S1）的当代晶体结构涵盖了重链（MHC）的马达结构域以及必需轻链（ELC）和调节轻链（RLC）。然而，在II型肌球蛋白的三维模型中，ELC的N端部分缺失。ELC的N端结构域具有有趣的功能特征，因为它与肌动蛋白结合从而控制肌球蛋白的马达活性。我们首次将ELC缺失的46个N端氨基酸建模到当代肌动蛋白-肌球蛋白-S1复合物上。我们展示了一种杆状的91埃结构，其长度足以弥合肌球蛋白-S1的ELC核心与肌动蛋白丝上ELC的适当结合位点之间的间隙。
