title: The fission yeast genes pyp1+ and pyp2+ encode protein tyrosine phosphatases that negatively regulate mitosis.
abstract: We have used degenerate oligonucleotide probes based on sequences conserved among known protein tyrosine phosphatases (PTPases) to identify two Schizosaccharomyces pombe genes encoding PTPases. We previously described the cloning of pyp1+ (S. Ottilie, J. Chernoff, G. Hannig, C. S. Hoffman, and R. L. Erikson, Proc. Natl. Acad. Sci. USA 88:3455-3459, 1991), and here we describe a second gene, called pyp2+. The C terminus of each protein contains sequences conserved in the apparent catalytic domains of all known PTPases. Disruption of pyp2+ results in viable cells, as was the case for pyp1+, whereas disruption of pyp2+ and pyp1+ results in synthetic lethality. Overexpression of either pyp1+ or pyp2+ in wild-type strains leads to a delay in mitosis but is suppressed by a wee1-50 mutation at 35 degrees C or a cdc2-1w mutation. A pyp1 disruption suppresses the temperature-sensitive lethality of a cdc25-22 mutation. Our data suggest that pyp1+ and pyp2+ act as negative regulators of mitosis upstream of the wee1+/mik1+ pathway.
authors.affiliation: Department of Cellular and Developmental Biology, Harvard University, Cambridge, Massachusetts 02138.
authors.forename: S
authors.initials: S
authors.lastname: Ottilie
authors.forename: J
authors.initials: J
authors.lastname: Chernoff
authors.forename: G
authors.initials: G
authors.lastname: Hannig
authors.forename: C S
authors.initials: CS
authors.lastname: Hoffman
authors.forename: R L
authors.initials: RL
authors.lastname: Erikson
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D015152:Blotting, Northern; D015139:Blotting, Southern; D018797:Cell Cycle Proteins; D003001:Cloning, Molecular; D004271:DNA, Fungal; D005800:Genes, Fungal; D008938:Mitosis; D008969:Molecular Sequence Data; D009154:Mutation; D017027:Protein Tyrosine Phosphatases / Q000235:genetics* / Q000378:metabolism; D012568:Schizosaccharomyces / Q000201:enzymology / Q000235:genetics*; D029702:Schizosaccharomyces pombe Proteins; D017386:Sequence Homology, Amino Acid; D013696:Temperature
chemical_list: D018797:Cell Cycle Proteins; D004271:DNA, Fungal; D029702:Schizosaccharomyces pombe Proteins; D017027:Protein Tyrosine Phosphatases; C097097:pyp1 protein, S pombe; C078759:pyp2 protein, S pombe