Degradation of the kinesin Kip1p at anaphase onset is mediated by the anaphase-promoting complex and Cdc20p.
Kip1p of Saccharomyces cerevisiae is a bipolar kinesin in the conserved bimC kinesin subfamily that mediates mitotic spindle-pole separation. Here, we show that Kip1p is regulated immediately after anaphase initiation by its rapid degradation. Degradation required the ubiquitin protein ligase called the anaphase-promoting complex, the anaphase-promoting complex activating protein Cdc20, and a unique 43-aa sequence in Kip1p. Degradation also required import of Kip1p into the nucleus, but occurred independently of spindle association. A mutation that stabilized Kip1p impaired anaphase progression. The timing of degradation suggests that Kip1p functions primarily during spindle assembly and metaphase, and that Kip1p degradation facilitates structural changes in the mitotic spindle as anaphase progresses.
Gordon
D M
DM
Program in Cell and Molecular Biology, Department of Animal Biology, University of Pennsylvania, 3800 Spruce Street, Philadelphia, PA 19104-6046, USA.
Roof
D M
DM
D000595:Amino Acid Sequence; D000705:Anaphase; D064173:Anaphase-Promoting Complex-Cyclosome; D064199:Cdc20 Proteins; D002453:Cell Cycle; D018797:Cell Cycle Proteins / Q000502:physiology*; D005656:Fungal Proteins / Q000737:chemistry / Q000378:metabolism*; D008025:Ligases / Q000502:physiology*; D008869:Microtubule-Associated Proteins / Q000737:chemistry / Q000378:metabolism*; D020409:Molecular Motor Proteins; D008969:Molecular Sequence Data; D029701:Saccharomyces cerevisiae Proteins; D043743:Ubiquitin-Protein Ligase Complexes; D044767:Ubiquitin-Protein Ligases
C577495:CDC20 protein, S cerevisiae; D064199:Cdc20 Proteins; D018797:Cell Cycle Proteins; D005656:Fungal Proteins; C431747:KIP1 protein, S cerevisiae; D008869:Microtubule-Associated Proteins; D020409:Molecular Motor Proteins; D029701:Saccharomyces cerevisiae Proteins; D043743:Ubiquitin-Protein Ligase Complexes; D064173:Anaphase-Promoting Complex-Cyclosome; D044767:Ubiquitin-Protein Ligases; D008025:Ligases