Regulation of KinI kinesin ATPase activity by binding to the microtubule lattice.
Regulation of KinI kinesin ATPase activity by binding to the microtubule lattice.
复制标题
DOI：
10.1083/jcb.200304034
复制
发表时间：
2003-12-08
期刊：
影响因子：
--
通讯作者：
Milligan RA
中科院分区：
文献类型：
--
作者：
Moores CA;Hekmat-Nejad M;Sakowicz R;Milligan RA
KinI驱动蛋白在调节微管细胞骨架的复杂动力学中是重要的。它们的不寻常之处在于它们是沿着微管移动的，而不是沿着微管移动。为了确定KinIs的属性，区分他们从易位驱动蛋白，我们研究了ATP酶活性，微管亲和力，和三维微管结合结构的最小KinI电机域。总之，动力学、亲和力和结构数据得出的结论是，在与微管晶格结合时，KinIs释放ADP并进入稳定的、低亲和力的、受调节的状态，从该状态它们不容易通过ATP酶循环进行。这种状态可能有利于KinI的分离或扩散到其作用部位，即微管末端。不同于传统的易位驱动蛋白，这是微管晶格刺激ATP酶，它似乎与KinIs，核苷酸介导的微管蛋白亲和力的调制是唯一可能的，当它耦合到原丝变形。这为它们独特的解聚活性提供了一个极好的机理基础。
KinI kinesins are important in regulating the complex dynamics of the microtubule cytoskeleton. They are unusual in that they depolymerize, rather than move along microtubules. To determine the attributes of KinIs that distinguish them from translocating kinesins, we examined the ATPase activity, microtubule affinity, and three-dimensional microtubule-bound structure of a minimal KinI motor domain. Together, the kinetic, affinity, and structural data lead to the conclusion that on binding to the microtubule lattice, KinIs release ADP and enter a stable, low-affinity, regulated state, from which they do not readily progress through the ATPase cycle. This state may favor detachment, or diffusion of the KinI to its site of action, the microtubule ends. Unlike conventional translocating kinesins, which are microtubule lattice–stimulated ATPases, it seems that with KinIs, nucleotide-mediated modulation of tubulin affinity is only possible when it is coupled to protofilament deformation. This provides an elegant mechanistic basis for their unique depolymerizing activity.
登录
查看更多内容
影响因子：
3.3
作者：
Kline-Smith, SL;Walczak, CE
通讯作者：
Walczak, CE
影响因子：
64.5
作者：
Sosa, H;Dias, DP;Milligan, RA
通讯作者：
Milligan, RA
影响因子：
16
作者：
Hunter, AW;Caplow, M;Howard, J
通讯作者：
Howard, J
影响因子：
5.6
作者：
Crevel, IMTC;Lockhart, A;Cross, RA
通讯作者：
Cross, RA
影响因子：
5.6
作者：
Niederstrasser, H;Salehi-Had, H;Nogales, E
通讯作者：
Nogales, E