The structure of full length human dynein-1 and the activation mechanism

报告题目：The structure of full length human dynein-1 and the activation mechanism

报告人：张凯博士，剑桥MRC分子生物学实验室博士后

报告时间：2016年7月12日（星期二）上午11:15-12:00

报告地点：中一楼3113

摘   要：

Human cytoplasmic dynein-1 is a 1.4 MDa motor protein complex with 12 subunits, which transports many important cargos to the minus end of microtubules. However, it only becomes an efficient, unidirectional motor when bound to the gigantic essential co-factor dynactin and a cargo adaptor protein (BICD2). We reported the structure of the 23-subunit dynactin complex by cryo-electron microscopy at 4.0Å overall and tail/dynactin/BicD complex at 8.2Å. The assembly mechanism of dynactin and its interaction with dynein-1 were unambiguously revealed. Cryo-EM structure of a full length human dynein-1 in the state of compact Phi particle has been solved to high resolution. All subunits have been identified from the 8Å map of dynein-1 tail with most helices built. The 3.8Å motor domain shows how dynein is auto-inhibited via dimerization. Key residues were identified in the interface. Mutagenesis revealed how these residues affect dimerization and processivity of dynein-1. A detailed activation mechanism has been proposed based on functional study and dynamic structural analysis of dynein-1 in Phi particle, open dynein alone and open dynein in dynein/dynactin/BicD (DDB) complex.

简 介：张凯博士，2008年本科毕业于哈尔滨工业大学生物技术专业;2013年博士毕业于生物物理研究所;2014至今在剑桥MRC分子生物学实验室从事博士后研究，主要研究方向为冷冻电镜，包括动力蛋白结构机理和冷冻电镜技术方法两方面。曾以《science》封面形式发表dynactin复合物近原子分辨率冷冻电镜结构，被论文评审专家誉为分子马达领域过去几十年最重要成果之一，具有里程碑式的意义；独立开发Gctf, Gautomatch等多个冷冻电镜相关程序，在提高精度和高度自动化的同时，上千倍的提高速度，大幅降低超算成本;程序一经发表便迅速被同行广泛传播和使用。近期研究包括人源动力蛋白高分辨率冷冻电镜结构、动态机理以及相应技术方法发展。