Reversal in the direction of movement of a molecular motor
Reversal in the direction of movement of a molecular motor
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DOI：
10.1038/38022
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发表时间：
1997-09-04
期刊：
影响因子：
64.8
通讯作者：
Schliwa, M
中科院分区：
文献类型：
--
作者：
Henningsen, U;Schliwa, M
驱动蛋白和非红细胞分离蛋白（ncd）是驱动蛋白超家族的分子马达，它们沿沿着以相反的方向运动。运动方向的分子基础尚不清楚，尽管它被认为是运动结构域的内在特性，运动结构域是一个长度约为330个氨基酸的保守区域（1-3）。马达结构域在常规驱动蛋白中位于氨基末端，但在ncd中位于羧基末端（4，5）。在这里，我们报告了由粗糙脉孢菌的负末端定向驱动蛋白的运动结构域组成的嵌合体（6）。使用极性标记的微管在运动性测定中测试细菌表达的融合蛋白（7）。令人惊讶的是，嵌合体向正端移动，表明ncd运动域产生力的极性已经逆转。这一发现表明，域的组织，特别是运动域的位置，是根本的重要性的极性生产力。它还表明微管运动的方向不仅仅由运动域控制（8）。
Kinesin and non-claret disjunctional (ncd) are molecular motors of the kinesin superfamily that move in opposite directions along microtubules. The molecular basis underlying the direction of movement is unclear, although it is thought to be an intrinsic property of the motor domain, a conserved region about 330 amino acids in length(1-3). The motor domain is found at the amino terminus in conventional kinesins, but at the carboxy terminus in ncd(4,5). Here we report on a chimaera composed of the motor domain of the minus-end-directed kinesin of Neurospora crassa(6). The bacterially expressed fusion protein was tested in motility assays using polarity-marked microtubules(7). Surprisingly, the chimaera moved towards the plus end, demonstrating that the polarity of force generation of the ncd motor domain has been reversed. This finding indicates that the domain organization, particularly the position of the motor domain, is of fundamental importance for the polarity of force production. It also demonstrates that the direction of microtubule movement is not controlled solely by the motor domain(8).