Premium
Allelism of Saccharomyces cerevisiae genes PSO6 , involved in survival after 3‐CPs+UVA induced damage, and ERG3 , encoding the enzyme sterol C‐5 desaturase
Author(s) -
Schmidt Clarice L.,
Grey Martin,
Schmidt Martin,
Brendel Martin,
Henriques João A. P.
Publication year - 1999
Publication title -
yeast
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.923
H-Index - 102
eISSN - 1097-0061
pISSN - 0749-503X
DOI - 10.1002/(sici)1097-0061(199910)15:14<1503::aid-yea481>3.0.co;2-w
Subject(s) - ergosterol , mutant , sterol , biology , saccharomyces cerevisiae , yeast , biochemistry , gene , cholesterol
Sequencing of the yeast gene that complemented the sensitivity to the photoactivated monofunctional 3‐carbethoxypsoralen of the pso6‐1 mutant strain revealed that the ERG3 locus, encoding sterol C‐5 desaturase involved in biosynthesis of ergosterol, is allelic to PSO6. Disruption of the ERG3 gene yielded an erg3 Δ mutant viable in ergosterol‐containing YEPD media with the same pleiotropic mutant phenotype known for pso6‐1 and erg3 mutants, including sensitivity to hydrogen peroxide and paraquat. Thus, the erg3/pso6 yeast mutant seems to be more sensitive than the WT to 3‐CPs+UVA because of the oxidative damage contributed by this treatment and not because of an impaired repair of the furocoumarin‐thymine monoadducts formed in the DNA. We found a significant increase of petites amongst erg3 Δ and pso6‐1 yeast mutant strains grown in conditions where respiration was mandatory. Mutant pso6‐1 , with its lowered content of ergosterol, exhibited enhanced synthesis of chitin that was maldistributed and not confined to the bud scars. Chitin overproduction in pso6/erg3 mutants resulted in hypersensitivity to Calcofluor White. Copyright © 1999 John Wiley & Sons, Ltd.