Ganguly Anindya, DeMott Logan, Dixit Ram
Biology Department, Washington University in St. Louis, St. Louis, MO 63130, USA.
Biology Department, Washington University in St. Louis, St. Louis, MO 63130, USA
J Cell Sci. 2017 Apr 1;130(7):1232-1238. doi: 10.1242/jcs.196857. Epub 2017 Feb 20.
Processivity is important for kinesins that mediate intracellular transport. Structure-function analyses of N-terminal kinesins (i.e. kinesins comprising their motor domains at the N-terminus) have identified several non-motor regions that affect processivity However, whether these structural elements affect kinesin processivity and function is not known. Here, we used an kinesin-4, called Fragile Fiber 1 (FRA1, also known as KIN4A), which is thought to mediate vesicle transport, to test whether mutations that alter processivity lead to similar changes in behavior and whether processivity is important for the function of FRA1. We generated several FRA1 mutants that differed in their 'run lengths' and then transformed them into the mutant for complementation and motility analyses. Our data show that the behavior of processivity mutants can differ dramatically from properties, underscoring the need to extend structure-function analyses of kinesins In addition, we found that a high density of processive motility is necessary for the physiological function of FRA1.
持续性对于介导细胞内运输的驱动蛋白来说很重要。对N端驱动蛋白（即其运动结构域位于N端的驱动蛋白）的结构-功能分析已经确定了几个影响持续性的非运动区域。然而，这些结构元件是否影响驱动蛋白的持续性和功能尚不清楚。在这里，我们使用了一种名为脆弱纤维1（FRA1，也称为KIN4A）的驱动蛋白-4，它被认为介导囊泡运输，以测试改变持续性的突变是否会导致行为上的类似变化，以及持续性对于FRA1的功能是否重要。我们生成了几个“运行长度”不同的FRA1突变体，然后将它们转化到突变体中进行互补和运动性分析。我们的数据表明，持续性突变体的行为可能与野生型特性有很大差异，这突出了扩展驱动蛋白结构-功能分析的必要性。此外，我们发现高频率的持续性运动对于FRA1的生理功能是必要的。
