TY - JOUR T1 - The Origin of Minus-end Directionality and Mechanochemistry of Ncd Motors A1 - Jana, Biman A1 - Hyeon, Changbong A1 - Onuchic, José N. Y1 - 2012/11/15 N2 - Author Summary Proteins belonging to the kinesin superfamily are responsible for vesicle or organelle transport, spindle morphogenesis, and chromosome sorting during cell division. Interestingly, while most proteins in kinesin superfamily that share the common catalytic motor head domain have plus-end directionality along microtubules, kinesin-14 (Ncd) exhibits minus-end directionality. Despite the several circumstantial evidences on the determining factors for the motor directionality in the last decade, a comprehensive understanding of the mechanism governing the Ncd minus-end directionality is still missing. Our studies provide a clear explanation for this minus-end directionality and the associated mechanochemical cycle. Here, we modeled an Ncd motor by employing structural details available in the literature to simulate its conformational dynamics. Simulations using our structure-based model of Ncd assert that the dynamics due to a simple rearrangement of structural elements, peripheral to the catalytic motor domain, is the key player in determining both the directionality and mechanochemistry unique to Ncd motors. Although Ncd has a different directionality, it uses a similar strategy to kinesin-1 of structural adaptation of the catalytic motor domain. Therefore using the same physical principle of protein folding and very similar structural elements, motors in the kinesin superfamily are able to achieve a variety of biological function. JF - PLOS Computational Biology JA - PLOS Computational Biology VL - 8 IS - 11 UR - https://doi.org/10.1371/journal.pcbi.1002783 SP - e1002783 EP - PB - Public Library of Science M3 - doi:10.1371/journal.pcbi.1002783 ER -