title: Rtt107 phosphorylation promotes localisation to DNA double-stranded breaks (DSBs) and recombinational repair between sister chromatids.
abstract: Efficient repair of DNA double-stranded breaks (DSB) requires a coordinated response at the site of lesion. Nucleolytic resection commits repair towards homologous recombination, which preferentially occurs between sister chromatids. DSB resection promotes recruitment of the Mec1 checkpoint kinase to the break. Rtt107 is a target of Mec1 and serves as a scaffold during repair. Rtt107 plays an important role during rescue of damaged replication forks, however whether Rtt107 contributes to the repair of DSBs is unknown. Here we show that Rtt107 is recruited to DSBs induced by the HO endonuclease. Rtt107 phosphorylation by Mec1 and its interaction with the Smc5-Smc6 complex are both required for Rtt107 loading to breaks, while Rtt107 regulators Slx4 and Rtt101 are not. We demonstrate that Rtt107 has an effect on the efficiency of sister chromatid recombination (SCR) and propose that its recruitment to DSBs, together with the Smc5-Smc6 complex is important for repair through the SCR pathway.
authors.affiliation: Cell Cycle Group, Medical Research Council, Clinical Sciences Centre, Imperial College, London, United Kingdom.
authors.forename: Pranav
authors.initials: P
authors.lastname: Ullal
authors.forename: Felipe
authors.initials: F
authors.lastname: Vilella-Mitjana
authors.forename: Adam
authors.initials: A
authors.lastname: Jarmuz
authors.forename: Luis
authors.initials: L
authors.lastname: Aragón
mesh_terms: D018797:Cell Cycle Proteins / Q000378:metabolism; D053903:DNA Breaks, Double-Stranded; D004260:DNA Repair / Q000235:genetics*; D004720:Endonucleases / Q000378:metabolism; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism; D009687:Nuclear Proteins / Q000378:metabolism*; D010766:Phosphorylation; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D021381:Protein Transport; D012441:Saccharomyces cerevisiae / Q000201:enzymology / Q000235:genetics* / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism*; D012854:Sister Chromatid Exchange / Q000235:genetics*
chemical_list: D018797:Cell Cycle Proteins; D047908:Intracellular Signaling Peptides and Proteins; D009687:Nuclear Proteins; C501265:RTT107 protein, S cerevisiae; C486627:SMC5 protein, S cerevisiae; C486631:SMC6 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; C088937:MEC1 protein, S cerevisiae; D017346:Protein Serine-Threonine Kinases; D004720:Endonucleases