Su, XiaoleiArellano-Santoyo, HugoPortran, DidierGaillard, JeremieVantard, MarylinThery, ManuelPellman, David2014-03-112013Su, Xiaolei, Hugo Arellano-Santoyo, Didier Portran, Jeremie Gaillard, Marylin Vantard, Manuel Thery, and David Pellman. 2013. “Microtubule sliding activity of a kinesin-8 promotes spindle assembly and spindle length control.” Nature cell biology 15 (8): 948-957. doi:10.1038/ncb2801. http://dx.doi.org/10.1038/ncb2801.1465-7392http://nrs.harvard.edu/urn-3:HUL.InstRepos:11879739Molecular motors play critical roles in the formation of mitotic spindles, either through controlling the stability of individual microtubules, or by cross-linking and sliding microtubule arrays. Kinesin-8 motors are best known for their regulatory roles in controlling microtubule dynamics. They contain microtubule-destabilizing activities, and restrict spindle length in a wide variety of cell types and organisms. Here, we report for the first time on an anti-parallel microtubule-sliding activity of the budding yeast kinesin-8, Kip3. The in vivo importance of this sliding activity was established through the identification of complementary Kip3 mutants that separate the sliding activity and microtubule destabilizing activity. In conjunction with kinesin-5/Cin8, the sliding activity of Kip3 promotes bipolar spindle assembly and the maintenance of genome stability. We propose a “slide-disassemble” model where Kip3’s sliding and destabilizing activity balance during pre-anaphase. This facilitates normal spindle assembly. However, Kip3’s destabilizing activity dominates in late anaphase, inhibiting spindle elongation and ultimately promoting spindle disassembly.en-USJournal Article2014-03-1110.1038/ncb2801