title: The EGP1 gene may be a positive regulator of protein phosphatase type 1 in the growth control of Saccharomyces cerevisiae.
abstract: The Saccharomyces cerevisiae GLC7 gene encodes the catalytic subunit of type 1 protein phosphatase (PP1) and is required for cell growth. A cold-sensitive glc7 mutant (glc7Y170) arrests in G2/M but remains viable at the restrictive temperature. In an effort to identify additional gene products that function in concert with PP1 to regulate growth, we isolated a mutation (gpp1) that exacerbated the growth phenotype of the glc7Y170 mutation, resulting in rapid death of the double mutant at the nonpermissive temperature. We identified an additional gene, EGP1, as an extra-copy suppressor of the glc7Y170 gpp1-1 double mutant. The nucleotide sequence of EGP1 predicts a leucine-rich repeat protein that is similar to Sds22, a protein from the fission yeast Schizosaccharomyces pombe that positively modulates PP1. EGP1 is essential for cell growth but becomes dispensable upon overexpression of the GLC7 gene. Egp1 and PP1 directly interact, as assayed by coimmunoprecipitation. These results suggest that Egp1 functions as a positive modulator of PP1 in the growth control of S. cerevisiae.
authors.affiliation: Department of Molecular Biology, Faculty of Science, Nagoya University, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Hisamoto
authors.forename: D L
authors.initials: DL
authors.lastname: Frederick
authors.forename: K
authors.initials: K
authors.lastname: Sugimoto
authors.forename: K
authors.initials: K
authors.lastname: Tatchell
authors.forename: K
authors.initials: K
authors.lastname: Matsumoto
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D002453:Cell Cycle / Q000235:genetics; D018797:Cell Cycle Proteins; D002467:Cell Nucleus / Q000473:pathology; D003001:Cloning, Molecular; D005455:Fluorescent Antibody Technique; D005656:Fungal Proteins / Q000235:genetics / Q000302:isolation & purification; D015966:Gene Expression Regulation, Fungal; D005800:Genes, Fungal / Q000235:genetics*; D005804:Genes, Lethal / Q000235:genetics; D005809:Genes, Regulator / Q000235:genetics*; D008870:Microtubules / Q000473:pathology; D008969:Molecular Sequence Data; D016296:Mutagenesis; D009687:Nuclear Proteins; D010749:Phosphoprotein Phosphatases / Q000302:isolation & purification / Q000378:metabolism*; D011233:Precipitin Tests; D012097:Repressor Proteins / Q000235:genetics* / Q000302:isolation & purification; D012441:Saccharomyces cerevisiae / Q000166:cytology / Q000235:genetics / Q000254:growth & development*; D029701:Saccharomyces cerevisiae Proteins; D029702:Schizosaccharomyces pombe Proteins; D017386:Sequence Homology, Amino Acid
chemical_list: D018797:Cell Cycle Proteins; D005656:Fungal Proteins; D009687:Nuclear Proteins; D012097:Repressor Proteins; D029701:Saccharomyces cerevisiae Proteins; D029702:Schizosaccharomyces pombe Proteins; C066843:sds22 protein, S pombe; D010749:Phosphoprotein Phosphatases; C094302:SDS22 protein, S cerevisiae