Dynein, Lis1 and CLIP-170 counteract Eg5-dependent centrosome separation during bipolar spindle assembly.

ABSTRACT: Bipolar spindle assembly critically depends on the microtubule plus-end-directed motor Eg5 that binds antiparallel microtubules and slides them in opposite directions. As such, Eg5 can produce the necessary outward force within the spindle that drives centrosome separation and inhibition of this antiparallel sliding activity results in the formation of monopolar spindles. Here, we show that upon depletion of the minus-end-directed motor dynein, or the dynein-binding protein Lis1, bipolar spindles can form in human cells with substantially less Eg5 activity, suggesting that dynein and Lis1 produce an inward force that counteracts the Eg5-dependent outward force. Interestingly, we also observe restoration of spindle bipolarity upon depletion of the microtubule plus-end-tracking protein CLIP-

SUBMITTER: Tanenbaum ME 

PROVIDER: S-EPMC2609737 | biostudies-literature | 2008 Dec

REPOSITORIES: biostudies-literature