Structure of the kinesin13-microtubule ring complex.
Structure of the kinesin13-microtubule ring complex.
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DOI：
10.1016/j.str.2008.08.017
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发表时间：
2008-11-12
期刊：
影响因子：
--
通讯作者：
Sosa H
中科院分区：
文献类型：
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作者：
Tan D;Rice WJ;Sosa H
为了研究驱动蛋白13诱导微管解聚的机制，我们使用冷冻电子显微镜（cryo-EM）和图像分析计算了驱动蛋白13-微管环复合物的三维（3D）图。通过将微管蛋白和驱动蛋白13运动域（MD）的晶体结构对接到3D图中来产生复合物的原子模型。该模型通过提供驱动蛋白13 MD和弯曲的微管蛋白原丝（PF）之间形成的复合物的3D视图，揭示了解聚机制的快照。这表明，由驱动蛋白13类特异性残基介导的接触在假定的微管结合位点稳定内二聚体微管蛋白曲率。此外，驱动蛋白13 MD上的微管蛋白结合位点被确定。在这类保守位点的突变选择性地破坏微管相关环复合物的形成。
To investigate the mechanism of kinesin13-induced microtubule depolymerization, we have calculated a three-dimensional (3D) map of the kinesin13-microtubule ring complex, using cryo-electron microscopy (cryo-EM) and image analysis. An atomic model of the complex was produced by docking the crystal structures of tubulin and a kinesin13 motor domain (MD) into the 3D map. The model reveals a snapshot of the depolymerization mechanism by providing a 3D view of the complex formed between the kinesin13 MD and a curved tubulin protofilament (pf). It suggests that contacts mediated by kinesin13 class-specific residues in the putative microtubule-binding site stabilize intra-dimer tubulin curvature. In addition, a tubulin-binding site on the kinesin13 MD was identified. Mutations at this class-conserved site selectively disrupt the formation of microtubule-associated ring complexes.