title: The Saccharomyces cerevisiae suppressor of choline sensitivity (SCS2) gene is a multicopy Suppressor of mec1 telomeric silencing defects.
abstract: Mec1p is a cell cycle checkpoint protein related to the ATM protein kinase family. Certain mec1 mutations or overexpression of Mec1p lead to shortened telomeres and loss of telomeric silencing. We conducted a multicopy suppressor screen for genes that suppress the loss of silencing in strains overexpressing Mec1p. We identified SCS2 (suppressor of choline sensitivity), a gene previously isolated as a suppressor of defects in inositol synthesis. Deletion of SCS2 resulted in decreased telomeric silencing, and the scs2 mutation increased the rate of cellular senescence observed for mec1-21 tel1 double mutant cells. Genetic analysis revealed that Scs2p probably acts through a different telomeric silencing pathway from that affected by Mec1p.
authors.affiliation: Department of Biology, Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, NC 27599-3280, USA.
authors.forename: R J
authors.initials: RJ
authors.lastname: Craven
authors.forename: T D
authors.initials: TD
authors.lastname: Petes
mesh_terms: D001483:Base Sequence; D017931:DNA Primers; D005656:Fungal Proteins / Q000235:genetics*; D020868:Gene Silencing; D005800:Genes, Fungal; D016153:Genes, Suppressor; D047908:Intracellular Signaling Peptides and Proteins; D008969:Molecular Sequence Data; D009154:Mutation; D010957:Plasmids; D017346:Protein Serine-Threonine Kinases; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins; D016615:Telomere
chemical_list: D017931:DNA Primers; D005656:Fungal Proteins; D047908:Intracellular Signaling Peptides and Proteins; D029701:Saccharomyces cerevisiae Proteins; C088937:MEC1 protein, S cerevisiae; D017346:Protein Serine-Threonine Kinases