Abstract:
Mitotic centromere-associated kinesin (MCAK) motor protein is a typical member of the kinesin-13 family, which can depolymerize microtubules from both plus and minus ends. A critical issue for the MCAK motor is how it performs the depolymerase activity. To address the issue, the pathway of the MCAK motor moving on microtubules and depolymerizing the microtubules is presented here. On the basis of the pathway, the dynamics of both the wild-type and mutant MCAK motors is studied theoretically, which include the full-length MCAK, the full-length MCAK with mutations in the α4-helix of the motor domain, the mutant full-length MCAK with a neutralized neck, the monomeric MCAK and the mutant monomeric MCAK with a neutralized neck. The studies show that a single dimeric MCAK motor can depolymerize microtubules in a processive manner, with either one tubulin or two tubulins being removed per times. The theoretical results are in agreement with the available experimental data. Moreover, predicted results are provided.
摘要:
有丝分裂着丝粒相关驱动蛋白(MCAK)运动蛋白是驱动蛋白-13家族的典型成员,可以从正端和负端解聚微管。MCAK电机的关键问题是它如何执行解聚酶活性。为了解决这个问题,这里介绍了MCAK电机在微管上移动并解聚微管的途径。在路径的基础上,从理论上研究了野生型和突变型MCAK电机的动力学,其中包括全长MCAK,在运动结构域的α4螺旋中具有突变的全长MCAK,颈部中和的突变体全长MCAK,单体MCAK和具有中和颈部的突变型单体MCAK。研究表明,单个二聚体MCAK马达可以以渐进的方式解聚微管,每次去除一个微管蛋白或两个微管蛋白。理论结果与可用的实验数据一致。此外,提供了预测结果。