Torque generation by one of the motor subunits of heterotrimeric kinesin-2

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• 作者：Xiaoyu Pan ; Seyda Acar ; Jonathan M. Scholey
• 关键词：Heterotrimeric kinesin-2 ; Torque generation ; Intraflagellar transport
• 刊名：Biochemical and Biophysical Research Communications
• 出版年：2010
• 出版时间：8 October 2010
• 年：2010
• 卷：401
• 期：1
• 页码：53-57
• 全文大小：464 K

文摘

Heterotrimeric kinesin-2 motors [1] and [2] transport intraflagellar transport (IFT)-particles from the base to the tip of the axoneme to assemble and maintain cilia [3], [4], [5], [6], [7], [8], [9] and [10]. These motors are distinct in containing two non-identical motor subunits together with an accessory subunit [1], [11], [12], [13], [14] and [15]. We evaluated the significance of this organization by comparing purified wild type kinesin-2 holoenzymes that support IFT in vivo, with mutant trimers containing only one type of motor domain that do not support IFT in vivo. In motility assays, wild type kinesin-2 moved microtubules (MTs) at a rate intermediate between the rates supported by the two mutants. Interestingly, one of the mutants, but not the other mutant or the wild type protein, was observed to drive a persistent counter-clock-wise rotation of the gliding MTs. Thus one of the two motor domains of heterotrimeric kinesin-2 exerts torque as well as axial force as it moves along a MT, which may allow kinesin-2 to control its circumferential position around a MT doublet within the cilium.