Klp2-mediated Rsp1-Mto1 colocalization inhibits microtubule-dependent microtubule assembly in fission yeast.

Microtubule assembly takes place at the centrosome and noncentrosomal microtubule-organizing centers (MTOCs). However, the mechanisms controlling the activity of noncentrosomal MTOCs are poorly understood. Here, using the fission yeast as a model organism, we demonstrate that the kinesin-14 motor Klp2 interacts with the J-domain Hsp70/Ssa1 cochaperone Rsp1, an inhibitory factor of microtubule assembly, and that Klp2 is required for the proper localization of Rsp1 to microtubules.

WDR62 regulates spindle dynamics as an adaptor protein between TPX2/Aurora A and katanin.

WDR62 is a microcephaly-related, microtubule (MT)-associated protein (MAP) that localizes to the spindle pole and regulates spindle organization, but the underlying mechanisms remain elusive. Here, we show that WDR62 regulates spindle dynamics by recruiting katanin to the spindle pole and further reveal a TPX2-Aurora A-WDR62-katanin axis in cells. By combining cellular and in vitro experiments, we demonstrate that WDR62 shows preference for curved segments of dynamic GDP-MTs, as well as GMPCPP- and paclitaxel-stabilized MTs, suggesting that it recognizes extended MT lattice.