Kinesin is associated with a nonmicrotubule component of sea urchin mitotic spindles.
Sea urchin embryos in second division have been lysed into microtubule-stabilizing buffers to yield mitotic cytoskeletons (MCSs) that consist of two mitotic spindles surrounded by a cortical array of filaments. Microtubules have been completely extracted from MCSs by incubation at 0 degrees C with Ca2+-containing buffer. An antibody to the microtubule translocator kinesin stains the spindles in MCSs and in MCSs treated with 5 mM ATP and also stains spindle-remnants of the MCSs after the microtubules have been extracted. We conclude that kinesin binds to a nonmicrotubule component in the mitotic spindle. Based on these results, we present several models of kinesin function in the spindle.
D000818:Animals; D000911:Antibodies, Monoclonal; D004625:Embryo, Nonmammalian / Q000166:cytology; D005260:Female; D016547:Kinesins; D008868:Microtubule Proteins / Q000032:analysis*; D008870:Microtubules / Q000648:ultrastructure; D009419:Nerve Tissue Proteins / Q000032:analysis*; D012617:Sea Urchins; D008941:Spindle Apparatus / Q000648:ultrastructure*; D014404:Tubulin / Q000032:analysis
D000911:Antibodies, Monoclonal; D008868:Microtubule Proteins; D009419:Nerve Tissue Proteins; D014404:Tubulin; D016547:Kinesins