A new model for binding of kinesin 13 to curved microtubule protofilaments

Anke M. Mulder, Alex Glavis-Bloom, Carolyn A. Moores, Michael Wagenbach, Bridget Carragher, Linda Wordeman, Ronald A. Milligan

Research output: Contribution to journalArticlepeer-review

32 Scopus citations

Abstract

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 1 3 binds to every hetero-dimer 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 proto-filament 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.

Original languageEnglish (US)
Pages (from-to)51-57
Number of pages7
JournalJournal of Cell Biology
Volume185
Issue number1
DOIs
StatePublished - Apr 6 2009

ASJC Scopus subject areas

  • Cell Biology

Fingerprint Dive into the research topics of 'A new model for binding of kinesin 13 to curved microtubule protofilaments'. Together they form a unique fingerprint.

Cite this