KENBIKYO Vol.53▶No.2 2018

Structural Basis of Multiple Functions of Kinesin Superfamily Proteins

Ryo Nitta

Abstract: Kinesin superfamily proteins move along the microtubules to accomplish the various functions including intracellular transport, mitosis, left-right determination, ciliary length control, and so on. I've solved the several kinesin structures complexed with the microtubules to elucidate the structural basis of the multiple functions of kinesin motors. In this review, I introduce four kinesin motors with the different characteristics, the plus-end directed Kinesin-3, the minus-end directed Kinesin-14, the microtubule depolymerizing Kinesin-13, and the dual functional Kinesin-8 which not only moves along the microtubule but also depolymerizes the microtubule. All kinesin motors utilize the conserved strategy, the attachment/detachment on/from the microtubule during the ATPase cycle. However, they have acquired multiple functions along the course of evolution, by the local conformational changes as well as the insertion of specific amino-acids at the microtubule-binding region or by the addition of the helical structures outside the motor domain to amplify the conformational changes occurring inside the motor domain.

Key words: Kinesin, Microtubule, Molecular Motor, Cryo-electron microscopy, X-ray crystallography