Feedback control of mitosis in budding yeast.
We have investigated the feedback control that prevents cells with incompletely assembled spindles from leaving mitosis. We isolated budding yeast mutants sensitive to the anti-microtubule drug benomyl. Mitotic arrest-deficient (mad) mutants are the subclass of benomyl-sensitive mutants in which the completion of mitosis is not delayed in the presence of benomyl and that die as a consequence of their premature exit from mitosis. A number of properties of the mad mutants indicate that they are defective in the feedback control over the exit from mitosis: their killing by benomyl requires passage through mitosis; their benomyl sensitivity can be suppressed by an independent method for delaying the exit from mitosis; they have normal microtubules; and they have increased frequencies of chromosome loss. We cloned MAD2, which encodes a putative calcium-binding protein whose disruption is lethal. We discuss the role of feedback controls in coordinating events in the cell cycle.
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Program in Cell Biology, University of California, San Francisco 94143-0444.
Murray
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D000595:Amino Acid Sequence; D001483:Base Sequence; D001542:Benomyl / Q000494:pharmacology; D002135:Calcium-Binding Proteins / Q000235:genetics*; D002352:Carrier Proteins; D002453:Cell Cycle; D018797:Cell Cycle Proteins; D002467:Cell Nucleus / Q000502:physiology; D015825:Chromosomes, Fungal / Q000378:metabolism; D003001:Cloning, Molecular; D003599:Cytoskeleton / Q000502:physiology; D004252:DNA Mutational Analysis; D004271:DNA, Fungal / Q000235:genetics; D005246:Feedback; D005656:Fungal Proteins / Q000235:genetics*; D005800:Genes, Fungal; D064246:Mad2 Proteins; D008870:Microtubules / Q000502:physiology*; D008938:Mitosis; D008969:Molecular Sequence Data; D009154:Mutation; D009687:Nuclear Proteins; D006656:Protamine Kinase / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000166:cytology*; D029701:Saccharomyces cerevisiae Proteins; D008941:Spindle Apparatus / Q000187:drug effects / Q000502:physiology*
D002135:Calcium-Binding Proteins; D002352:Carrier Proteins; D018797:Cell Cycle Proteins; D004271:DNA, Fungal; D005656:Fungal Proteins; C577695:MAD2 protein, S cerevisiae; D064246:Mad2 Proteins; D009687:Nuclear Proteins; D029701:Saccharomyces cerevisiae Proteins; D006656:Protamine Kinase; D001542:Benomyl