Kinesin's tail domain is an inhibitory regulator of the motor domain
Kinesin's tail domain is an inhibitory regulator of the motor domain
复制标题
DOI：
10.1038/13001
复制
发表时间：
1999-09-01
影响因子：
21.3
通讯作者：
Howard, J
中科院分区：
文献类型：
--
作者：
Coy, DL;Hancock, WO;Howard, J
当不与货物结合时，运动蛋白Kinesin处于抑制状态，微管刺激的ATPase活性较低。抑制作用是为了最大限度地减少ATP的消耗，防止激动素在细胞中的错误定位。在这里，我们表明，当激动素与人造货物结合时，这种抑制作用就会解除。抑制是通过Kinesin的尾部结构域介导的：删除尾部可以激活ATPase，而不需要结合货物，添加外源尾肽可以重新建立抑制。ATPase和运动性分析都表明，尾巴并没有阻止激动素与微管的结合，而是降低了马达的步进率。
When not bound to cargo, the motor protein kinesin is in an inhibited state that has low microtubule-stimulated ATPase activity. Inhibition serves to minimize the dissipation of ATP and to prevent mislocalization of kinesin in the cell. Here we show that this inhibition is relieved when kinesin binds to an artificial cargo. Inhibition is mediated by kinesin's tail domain: deletion of the tail activates the ATPase without need of cargo binding, and inhibition is re-established by addition of exogenous tail peptide. Both ATPase and motility assays indicate that the tail does not prevent kinesin from binding to microtubules, but rather reduces the motor's stepping rate.