Yamada Masami, Toba Shiori, Yoshida Yuko, Haratani Koji, Mori Daisuke, Yano Yoshihisa, Mimori-Kiyosue Yuko, Nakamura Takeshi, Itoh Kyoko, Fushiki Shinji, Setou Mitsutoshi, Wynshaw-Boris Anthony, Torisawa Takayuki, Toyoshima Yoko Y, Hirotsune Shinji
Department of Genetic Disease Research, Osaka City University Graduate School of Medicine, Osaka, Japan.
EMBO J. 2008 Oct 8;27(19):2471-83. doi: 10.1038/emboj.2008.182. Epub 2008 Sep 11.
LIS1 was first identified as a gene mutated in human classical lissencephaly sequence. LIS1 is required for dynein activity, but the underlying mechanism is poorly understood. Here, we demonstrate that LIS1 suppresses the motility of cytoplasmic dynein on microtubules (MTs), whereas NDEL1 releases the blocking effect of LIS1 on cytoplasmic dynein. We demonstrate that LIS1, cytoplasmic dynein and MT fragments co-migrate anterogradely. When LIS1 function was suppressed by a blocking antibody, anterograde movement of cytoplasmic dynein was severely impaired. Immunoprecipitation assay indicated that cytoplasmic dynein forms a complex with LIS1, tubulins and kinesin-1. In contrast, immunoabsorption of LIS1 resulted in disappearance of co-precipitated tubulins and kinesin. Thus, we propose a novel model of the regulation of cytoplasmic dynein by LIS1, in which LIS1 mediates anterograde transport of cytoplasmic dynein to the plus end of cytoskeletal MTs as a dynein-LIS1 complex on transportable MTs, which is a possibility supported by our data.
LIS1最初被鉴定为在人类经典无脑回序列中发生突变的基因。LIS1是动力蛋白活性所必需的，但潜在机制尚不清楚。在这里，我们证明LIS1抑制细胞质动力蛋白在微管（MTs）上的运动，而NDEL1则解除LIS1对细胞质动力蛋白的阻断作用。我们证明LIS1、细胞质动力蛋白和MT片段同向顺行迁移。当LIS1功能被阻断抗体抑制时，细胞质动力蛋白的顺行运动严重受损。免疫沉淀试验表明，细胞质动力蛋白与LIS1、微管蛋白和驱动蛋白-1形成复合物。相反，LIS1的免疫吸附导致共沉淀的微管蛋白和驱动蛋白消失。因此，我们提出了一种由LIS1调节细胞质动力蛋白的新模型，其中LIS1作为动力蛋白-LIS1复合物在可运输的MTs上介导细胞质动力蛋白向细胞骨架MTs正端的顺行运输，我们的数据支持了这一可能性。
