Mulder, A.M. and Glavis-Bloom, A. and Moores, Carolyn A. and Wagenbach, M. and Carragher, B. and Wordeman, L. and Milligan, R.A. (2009) A new model for binding of kinesin 13 to curved microtubule protofilaments. Journal of Cell Biology 185 (1), pp. 51-57. ISSN 0021-9525.Full text not available from this repository.
Kinesin motor proteins use adenosine triphosphate hydrolysis to do work on microtubules (MTs). Most kinesins walk along the MT, but class 13 kinesins instead uniquely recognize MT ends and depolymerize MT protofilaments. We have used electron microscopy (EM) to understand the molecular interactions by which kinesin 13 performs these tasks. Although a construct of only the motor domain of kinesin 13 binds to every heterodimer of a tubulin ring, a construct containing the neck and the motor domain occupies alternate binding sites. Likewise, EM maps of the dimeric full-length (FL) protein exhibit alternate site binding but reveal density for only one of two motor heads. These results indicate that the second head of dimeric kinesin 13 does not have access to adjacent binding sites on the curved protofilament and suggest that the neck alone is sufficient to obstruct access. Additionally, the FL construct promotes increased stacking of rings compared with other constructs. Together, these data suggest a model for kinesin 13 depolymerization in which increased efficiency is achieved by binding of one kinesin 13 molecule to adjacent protofilaments.
|School or Research Centre:||Birkbeck Schools and Research Centres > School of Science > Biological Sciences|
|Date Deposited:||04 Aug 2010 14:09|
|Last Modified:||17 Apr 2013 12:17|
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