Chl1 and Ctf4 are required for damage-induced recombinations.
Deletion mutants of CHL1 or CTF4, which are required for sister chromatid cohesion, showed higher sensitivity to the DNA damaging agents methyl methanesulfonate (MMS), hydroxyurea (HU), phleomycin, and camptothecin, similar to the phenotype of mutants of RAD52, which is essential for recombination repair. The levels of Chl1 and Ctf4 associated with chromatin increased considerably after exposure of the cells to MMS and phleomycin. Although the activation of DNA damage checkpoint did not affected in chl1 and ctf4 mutants, the repair of damaged chromosome was inefficient, suggesting that Chl1 and Ctf4 act in DNA repair. In addition, MMS-induced sister chromatid recombination in haploid cells, and, more importantly, MMS-induced recombination between homologous chromosomes in diploid cells were impaired in these mutants. Our results suggest that Chl1 and Ctf4 are directly involved in homologous recombination repair rather than acting indirectly via the establishment of sister chromatid cohesion.
Ogiwara
Hideaki
H
Molecular Cell Biology Laboratory, Graduate School of Pharmaceutical Sciences, Tohoku University, Aoba 6-3, Aramaki, Aoba-ku, Sendai 980-8578, Japan.
Ui
Ayako
A
Lai
Mong Sing
MS
Enomoto
Takemi
T
Seki
Masayuki
M
D002868:Chromosomal Proteins, Non-Histone / Q000235:genetics*; D004249:DNA Damage / Q000235:genetics*; D004260:DNA Repair / Q000235:genetics*; D004271:DNA, Fungal / Q000235:genetics*; D004268:DNA-Binding Proteins / Q000235:genetics*; D042822:Genomic Instability / Q000235:genetics*; D011995:Recombination, Genetic / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics*; D012854:Sister Chromatid Exchange / Q000235:genetics
C066751:CHL1 protein, S cerevisiae; C078338:CTF4 protein, S cerevisiae; D002868:Chromosomal Proteins, Non-Histone; D004271:DNA, Fungal; D004268:DNA-Binding Proteins; D029701:Saccharomyces cerevisiae Proteins