Interaction between Ustilago maydis REC2 and RAD51 genes in DNA repair and mitotic recombination
Ferguson, D.O.; Rice, M.C.; Rendi, M.H.; Kotani, H.; Kmiec, E.B.; Holloman, W.K.
Genetics 145(2): 243-251
1997
ISSN/ISBN: 0016-6731 PMID: 9071580 Document Number: 477139
A gene encoding a Ustilago maydis Rad51 orthologue has been isolated, rad51-1, a mutant constructed by disrupting the gene, was as sensitive to killing by ultraviolet light and gamma radiation as the rec2-1 mutant and slightly more sensitive to killing by methyl methanesulfonate. There was no suppression of killing by ultraviolet light when a rec2-1 strain was transformed with a multicopy plasmid containing RAD51, nor was there suppression when rad51-1 was transformed with a multicopy plasmid containing REC2. Recombination proficiency as measured by a gap repair assay was diminished in both rec2-1 and rad51-1 strains. In rec2-1 the frequency of recombination was decreased, but the spectrum of events was similar to that observed in wild type, while in rad51-1 the frequency as well as the spectrum of recombination events were different. Studies with the rec2-1 rad51-1 double mutant indicated that there was epistasis in the action of REC2 and RAD51 in certain repair and recombination functions, but some measure of independent action in other functions.