A mutation in PLC1, a candidate phosphoinositide-specific phospholipase C gene from Saccharomyces cerevisiae, causes aberrant mitotic chromosome segregation.
We identified a putative Saccharomyces cerevisiae homolog of a phosphoinositide-specific phospholipase C (PI-PLC) gene, PLC1, which encodes a protein most similar to the delta class of PI-PLC enzymes. The PLC1 gene was isolated during a study of yeast strains that exhibit defects in chromosome segregation. plc1-1 cells showed a 10-fold increase in aberrant chromosome segregation compared with the wild type. Molecular analysis revealed that PLC1 encodes a predicted protein of 101 kDa with approximately 50 and 26% identity to the highly conserved X and Y domains of PI-PLC isozymes from humans, bovines, rats, and Drosophila melanogaster. The putative yeast protein also contains a consensus EF-hand domain that is predicted to bind calcium. Interestingly, the temperature-sensitive and chromosome missegregation phenotypes exhibited by plc1-1 cells were partially suppressed by exogenous calcium.
Department of Biochemistry and Molecular Biology, University of Massachusetts, Amherst 01003.
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Payne
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Fitzgerald-Hayes
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002118:Calcium / Q000502:physiology; D002875:Chromosomes / Q000378:metabolism; D003001:Cloning, Molecular; D004271:DNA, Fungal; D005800:Genes, Fungal; D006801:Humans; D008938:Mitosis; D008969:Molecular Sequence Data; D009154:Mutation; D010641:Phenotype; D043265:Phosphatidylinositol Diacylglycerol-Lyase; D010716:Phosphatidylinositols / Q000378:metabolism*; D054801:Phosphoinositide Phospholipase C; D010727:Phosphoric Diester Hydrolases / Q000235:genetics* / Q000378:metabolism; D015183:Restriction Mapping; D012441:Saccharomyces cerevisiae / Q000201:enzymology / Q000235:genetics* / Q000254:growth & development; D017386:Sequence Homology, Amino Acid; D013696:Temperature
D004271:DNA, Fungal; D010716:Phosphatidylinositols; D010727:Phosphoric Diester Hydrolases; D054801:Phosphoinositide Phospholipase C; D043265:Phosphatidylinositol Diacylglycerol-Lyase; D002118:Calcium