A plus-end-directed motor enzyme that moves antiparallel microtubules in vitro localizes to the interzone of mitotic spindles.
Mitosis comprises a complex set of overlapping motile events, many of which involve microtubule-dependent motor enzymes. Here we describe a new member of the kinesin superfamily. The protein was originally identified as a spindle antigen by the CHO1 monoclonal antibody and shown to be required for mitotic progression. We have cloned the gene that encodes this antigen and found that its sequence contains a domain with strong sequence similarity to the motor domain of kinesin-like proteins. The product of this gene, expressed in bacteria, can cross-bridge antiparallel microtubules in vitro, and in the presence of Mg-ATP, microtubules slide over one another in a fashion reminiscent of microtubule movements during spindle elongation.
Nislow
C
C
Department of Molecular, Cellular and Developmental Biology, University of Colorado, Boulder 80309.
Lombillo
V A
VA
Kuriyama
R
R
McIntosh
J R
JR
D000255:Adenosine Triphosphate / Q000494:pharmacology; D000595:Amino Acid Sequence; D000818:Animals; D000911:Antibodies, Monoclonal; D001483:Base Sequence; D006367:HeLa Cells; D006801:Humans; D015151:Immunoblotting; D007163:Immunosorbent Techniques; D016547:Kinesins / Q000737:chemistry / Q000235:genetics / Q000502:physiology; D008869:Microtubule-Associated Proteins / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D008870:Microtubules / Q000502:physiology*; D008938:Mitosis / Q000502:physiology; D008969:Molecular Sequence Data; D009068:Movement; D012689:Sequence Homology, Nucleic Acid; D008941:Spindle Apparatus / Q000201:enzymology*; D013768:Tetrahymena / Q000648:ultrastructure
D000911:Antibodies, Monoclonal; D008869:Microtubule-Associated Proteins; D000255:Adenosine Triphosphate; D016547:Kinesins