title: Late S phase-specific recruitment of Mre11 complex triggers hierarchical assembly of telomere replication proteins in Saccharomyces cerevisiae.
abstract: In Saccharomyces cerevisiae, telomere replication occurs in late S phase and is accompanied by dynamic remodeling of its protein components. Here, we show that MRX (Mre11-Rad50-Xrs2), an evolutionarily conserved protein complex involved in DNA double-strand break (DSB) repair, is recruited to the telomeres in late S phase. MRX is required for the late S phase-specific recruitment of ATR-like kinase Mec1 to the telomeres. Mec1, in turn, contributes to the assembly of the telomerase regulators Cdc13 and Est1 at the telomere ends. Our results provide a model for the hierarchical assembly of telomere-replication proteins in late S phase; this involves triggering by the loading of MRX onto the chromosome termini. The recruitment of DNA repair-related proteins to the telomeres at particular times in the cell cycle suggests that the normal terminus of a chromosome is recognized as a DSB during the course of replication.
authors.affiliation: Department of Geriatric Research, National Institute for Longevity Sciences, Obu, Aichi 474-8522, Japan.
authors.forename: Hideki
authors.initials: H
authors.lastname: Takata
authors.forename: Yayoi
authors.initials: Y
authors.lastname: Tanaka
authors.forename: Akira
authors.initials: A
authors.lastname: Matsuura
mesh_terms: D047369:Chromatin Immunoprecipitation; D004247:DNA / Q000235:genetics; D004260:DNA Repair; D004261:DNA Replication; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D004706:Endodeoxyribonucleases / Q000235:genetics* / Q000378:metabolism; D005090:Exodeoxyribonucleases / Q000235:genetics* / Q000378:metabolism; D047908:Intracellular Signaling Peptides and Proteins; D010641:Phenotype; D017346:Protein Serine-Threonine Kinases; D016196:S Phase; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics* / Q000378:metabolism; D016615:Telomere / Q000235:genetics* / Q000378:metabolism
chemical_list: D004268:DNA-Binding Proteins; D047908:Intracellular Signaling Peptides and Proteins; C086930:RAD50 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; C086929:XRS2 protein, S cerevisiae; D004247:DNA; C088937:MEC1 protein, S cerevisiae; D017346:Protein Serine-Threonine Kinases; D004706:Endodeoxyribonucleases; D005090:Exodeoxyribonucleases; C094191:MRE11 protein, S cerevisiae