Microtubule interaction site of the kinesin motor
Microtubule interaction site of the kinesin motor
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DOI：
10.1016/s0092-8674(00)80329-3
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发表时间：
1997-07-25
期刊：
影响因子：
64.5
通讯作者：
Vale, RD
中科院分区：
文献类型：
--
作者：
Woehlke, G;Ruby, AK;Vale, RD
驱动蛋白和肌球蛋白是马达蛋白，它们共享共同的结构核心并分别结合到微管和肌动蛋白丝。虽然肌动球蛋白界面已经得到了很好的研究，驱动蛋白上的微管结合位点的位置还没有确定。使用丙氨酸扫描诱变，我们已经发现，微管相互作用的驱动蛋白残基位于三个环，簇在一个补丁上的电机表面。关键残基主要是带正电荷的，这与带负电荷的微管蛋白分子的主要静电相互作用一致。微管结合界面的核心位于高度保守的环和螺旋（L12/α 5）中，其在拓扑学上对应于肌球蛋白的主要肌动蛋白结合结构域。因此，驱动蛋白和肌球蛋白在其共同的催化核心的相似区域中形成了不同的聚合物结合结构域。
Kinesin and myosin are motor proteins that share a common structural core and bind to microtubules and actin filaments, respectively. While the actomyosin interface has been well studied, the location of the microtubule-binding site on kinesin has not been identified. Using alanine-scanning mutagenesis, we have found that microtubule-interacting kinesin residues are located in three loops that cluster in a patch on the motor surface. The critical residues are primarily positively charged, which is consistent with a primarily electrostatic interaction with the negatively charged tubulin molecule. The core of the microtubule-binding interface resides in a highly conserved loop and helix (L12/alpha 5) that corresponds topologically to the major actin-binding domain of myosin. Thus, kinesin and myosin have developed distinct polymer-binding domains in a similar region with respect to their common catalytic cores.