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Single-headed mode of kinesin-5.

ABSTRACT: In most organisms, kinesin-5 motors are essential for mitosis and meiosis, where they crosslink and slide apart the antiparallel microtubule half-spindles. Recently, it was shown using single-molecule optical trapping that a truncated, double-headed human kinesin-5 dimer can step processively along microtubules. However, processivity is limited ( approximately 8 steps) with little coordination between the heads, raising the possibility that kinesin-5 motors might also be able to move by a nonprocessive mechanism. To investigate this, we engineered single-headed kinesin-5 dimers. We show that a set of these single-headed Eg5 dimers drive microtubule sliding at about 90% of wild-type velocity, indicating that Eg5 can slide microtubules by a mechanism in which one head of each Eg5 head-pair is effectively redundant. On the basis of this, we propose a muscle-like model for Eg5-driven microtubule sliding in spindles in which most force-generating events are single-headed interactions and alternate-heads processivity is rare.

SUBMITTER: Kaseda K

PROVIDER: S-EPMC2515207 | biostudies-other | 2008 Aug

REPOSITORIES: biostudies-other

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Single-headed mode of kinesin-5.

Kaseda Kuniyoshi K Crevel Isabelle I Hirose Keiko K Cross Robert A RA

EMBO reports 20080613 8

In most organisms, kinesin-5 motors are essential for mitosis and meiosis, where they crosslink and slide apart the antiparallel microtubule half-spindles. Recently, it was shown using single-molecule optical trapping that a truncated, double-headed human kinesin-5 dimer can step processively along microtubules. However, processivity is limited ( approximately 8 steps) with little coordination between the heads, raising the possibility that kinesin-5 motors might also be able to move by a nonpro ...[more]

PMID: 18552767

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