title: Involvement of the PP2C-like phosphatase Ptc2p in the DNA checkpoint pathways of Saccharomyces cerevisiae.
abstract: RAD53 encodes a conserved protein kinase that acts as a central transducer in the DNA damage and the DNA replication checkpoint pathways in Saccharomyces cerevisiae. To identify new elements of these pathways acting with or downstream of RAD53, we searched for genes whose overexpression suppressed the toxicity of a dominant-lethal form of RAD53 and identified PTC2, which encodes a protein phosphatase of the PP2C family. PTC2 overexpression induces hypersensitivity to genotoxic agents in wild-type cells and is lethal to rad53, mec1, and dun1 mutants with low ribonucleotide reductase activity. Deleting PTC2 specifically suppresses the hydroxyurea hypersensitivity of mec1 mutants and the lethality of mec1Delta. PTC2 is thus implicated in one or several functions related to RAD53, MEC1, and the DNA checkpoint pathways.
authors.affiliation: Service de Biochimie et de Génétique Moléculaire, CEA/Saclay, 91191 Gif-Sur-Yvette Cedex, France. marsolie@jonas.saclay.cea.fr
authors.forename: M C
authors.initials: MC
authors.lastname: Marsolier
authors.forename: P
authors.initials: P
authors.lastname: Roussel
authors.forename: C
authors.initials: C
authors.lastname: Leroy
authors.forename: C
authors.initials: C
authors.lastname: Mann
mesh_terms: D000483:Alleles; D001483:Base Sequence; D018797:Cell Cycle Proteins; D064447:Checkpoint Kinase 2; D017931:DNA Primers; D004271:DNA, Fungal / Q000235:genetics*; D005804:Genes, Lethal; D010749:Phosphoprotein Phosphatases / Q000378:metabolism*; D011494:Protein Kinases / Q000235:genetics; D054648:Protein Phosphatase 2; D000071636:Protein Phosphatase 2C; D017346:Protein Serine-Threonine Kinases; D012264:Ribonucleotide Reductases / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000201:enzymology / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins; D013379:Substrate Specificity
chemical_list: D018797:Cell Cycle Proteins; D017931:DNA Primers; D004271:DNA, Fungal; D029701:Saccharomyces cerevisiae Proteins; D012264:Ribonucleotide Reductases; D011494:Protein Kinases; D064447:Checkpoint Kinase 2; D017346:Protein Serine-Threonine Kinases; C067022:RAD53 protein, S cerevisiae; C087358:PTC1 protein, S cerevisiae; D010749:Phosphoprotein Phosphatases; D054648:Protein Phosphatase 2; D000071636:Protein Phosphatase 2C