The pso4-1 mutation reduces spontaneous mitotic gene conversion and reciprocal recombination in Saccharomyces cerevisiae.
Spontaneous mitotic recombination was examined in the haploid pso4-1 mutant of Saccharomyces cerevisiae and in the corresponding wild-type strain. Using a genetic system involving a duplication of the his4 gene it was shown that the pso4-1 mutation decreases at least fourfold the spontaneous rate of mitotic recombination. The frequency of spontaneous recombination was reduced tenfold in pso4-1 strains, as previously observed in the rad52-1 mutant. However, whereas the rad52-1 mutation specifically reduces gene conversion, the pso4-1 mutation reduces both gene conversion and reciprocal recombination. Induced mitotic recombination was also studied in pso4-1 mutant and wild-type strains after treatment with 8-methoxypsoralen plus UVA and 254 nm UV irradiation. Consistent with previous results, the pso4-1 mutation was found strongly to affect recombination induction.
Meira
L B
LB
Departamento de Biofisica, UFRGS, Porto Alegre, RS, Brazil.
Fonseca
M B
MB
Averbeck
D
D
Schenberg
A C
AC
Henriques
J A
JA
D004271:DNA, Fungal / Q000235:genetics; D004307:Dose-Response Relationship, Radiation; D005785:Gene Conversion; D005800:Genes, Fungal / Q000187:drug effects / Q000528:radiation effects; D005838:Genotype; D006238:Haploidy; D008730:Methoxsalen / Q000494:pharmacology; D008938:Mitosis / Q000235:genetics; D009154:Mutation; D011995:Recombination, Genetic; D015183:Restriction Mapping; D012441:Saccharomyces cerevisiae / Q000187:drug effects / Q000235:genetics* / Q000528:radiation effects; D014466:Ultraviolet Rays
D004271:DNA, Fungal; D008730:Methoxsalen