Repair of plasmid and genomic DNA in a rad7 delta mutant of yeast.

AUTOR(ES)

Mueller, J P

RESUMO

Repair of UV-induced cyclobutane pyrimidine dimers (CPDs) was examined in a yeast plasmid of known chromatin structure and in genomic DNA in a radiation-sensitive deletion mutant of yeast, rad7 delta, and its isogenic wild-type strain. A whole plasmid repair assay revealed that only approximately 50% of the CPDs in plasmid DNA are repaired after 6 h in this mutant, compared with almost 90% repaired in wild-type. Using a site-specific repair assay on 44 individual CPD sites within the plasmid we found that repair in the rad7 delta mutant occurred primarily in the transcribed regions of each strand of the plasmid, however, the rate of repair at nearly all sites measured was less than in the wild-type. There was no apparent correlation between repair rate and nucleosome position. In addition, approximately 55% of the CPDs in genomic DNA of the mutant are repaired during the 6 h period, compared with > 80% in the wild-type.

Documentos Relacionados

• Regulated expression of the Saccharomyces cerevisiae DNA repair gene RAD7 in response to DNA damage and during sporulation.
• RAD7 gene of Saccharomyces cerevisiae: transcripts, nucleotide sequence analysis, and functional relationship between the RAD7 and RAD23 gene products.
• Single strand and double strand DNA damage-induced reciprocal recombination in yeast. Dependence on nucleotide excision repair and RAD1 recombination.
• DNA helicases in recombination and repair: construction of a delta uvrD delta helD delta recQ mutant deficient in recombination and repair.
• The role of recombination and RAD52 in mutation of chromosomal DNA transformed into yeast.