RESUMO
The fission yeast-Schizosaccharomyces pombe-has emerged as a powerful tractable system for studying DNA damage repair. Over the last few decades, several powerful in vivo genetic assays have been developed to study outcomes of mitotic recombination, the major repair mechanism of DNA double strand breaks and stalled or collapsed DNA replication forks. These assays have significantly increased our understanding of the molecular mechanisms underlying the DNA damage response pathways. Here, we review the assays that have been developed in fission yeast to study mitotic recombination.
Assuntos
Replicação do DNA/genética , Mitose/genética , Recombinação Genética/genética , Divisão Celular/genética , Quebras de DNA de Cadeia Dupla , DNA Helicases/genética , Reparo do DNA/genética , Proteínas de Ligação a DNA/genética , Mitose/fisiologia , Schizosaccharomyces/genética , Proteínas de Schizosaccharomyces pombe/genéticaRESUMO
An accurate DNA damage response pathway is critical for the repair of DNA double-strand breaks. Repair may occur by homologous recombination, of which many different sub-pathways have been identified. Some recombination pathways are conservative, meaning that the chromosome sequences are preserved, and others are non-conservative, leading to some alteration of the DNA sequence. We describe an in vivo genetic assay to study non-conservative intra-chromosomal deletions at regions of non-tandem direct repeats in Schizosaccharomyces pombe. This assay can be used to study both spontaneous breaks arising during DNA replication and induced double-strand breaks created with the S. cerevisiae homothallic endonuclease (HO). The preliminary genetic validation of this assay shows that spontaneous breaks require rad52+ but not rad51+, while induced breaks require both genes, in agreement with previous studies. This assay will be useful in the field of DNA damage repair for studying mechanisms of intra-chromosomal deletions.