Brazilian Biosciences National Laboratory, National Center for Research in Energy and Materials, Campinas, São Paulo 13083-100, Brazil.
Structural Genomics Consortium, University of Oxford, Oxford OX3 7DQ, United Kingdom.
J Biol Chem. 2013 Nov 22;288(47):34131-34145. doi: 10.1074/jbc.M113.507202. Epub 2013 Oct 4.
Myosin V (MyoV) motors have been implicated in the intracellular transport of diverse cargoes including vesicles, organelles, RNA-protein complexes, and regulatory proteins. Here, we have solved the cargo-binding domain (CBD) structures of the three human MyoV paralogs (Va, Vb, and Vc), revealing subtle structural changes that drive functional differentiation and a novel redox mechanism controlling the CBD dimerization process, which is unique for the MyoVc subclass. Moreover, the cargo- and motor-binding sites were structurally assigned, indicating the conservation of residues involved in the recognition of adaptors for peroxisome transport and providing high resolution insights into motor domain inhibition by CBD. These results contribute to understanding the structural requirements for cargo transport, autoinhibition, and regulatory mechanisms in myosin V motors.
肌球蛋白 V(MyoV)分子马达参与多种货物的细胞内运输,包括囊泡、细胞器、RNA-蛋白复合物和调节蛋白。在这里,我们解析了三种人类 MyoV 同源物(Va、Vb 和 Vc)的货物结合结构域(CBD),揭示了微妙的结构变化,这些变化驱动了功能分化和一种新的氧化还原机制来控制 CBD 二聚化过程,这是 MyoVc 亚类所特有的。此外,还对货物和马达结合位点进行了结构分配,表明了参与过氧化物酶体运输接头识别的残基的保守性,并为马达结构域抑制提供了高分辨率的见解。这些结果有助于理解肌球蛋白 V 分子马达在货物运输、自身抑制和调节机制方面的结构要求。