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Mating type-like conversion promoted by the 2 micrograms circle site-specific recombinase: implications for the double-strand-gap repair model.

M Jayaram
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Abstract

Double-strand breaks in DNA are known to promote recombination in Saccharomyces cerevisiae. Yeast mating type switching, which is a highly efficient gene conversion event, is apparently initiated by a site-specific double-strand break. The 2 micrograms circle site-specific recombinase, FLP, has been shown to make double-strand breaks in its substrate DNA. By using a hybrid 2 micrograms circle::Tn5 plasmid, a portion of which resembles, in its DNA organization, the active (MAT) and the silent (HML) yeast mating type loci, it is shown that FLP mediates a conversion event analogous to mating type switching. Whereas the FLP site-specific recombination is not dependent on the RAD52 gene product, the FLP-induced conversion is abolished in a rad52 background. The FLP-promoted conversion in vivo can be faithfully reproduced by making a double-stranded gap in vitro in the vicinity of the FLP site and allowing the gap to be repaired in vivo.

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Crosses, GeneticDNA NucleotidyltransferasesDNA RepairDNA Restriction EnzymesDNA Transposable ElementsGenes, FungalGenes, Mating Type, FungalPlasmidsRecombination, GeneticSaccharomyces cerevisiaeJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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BibTeXRIS

M Jayaram. 1986. Mating type-like conversion promoted by the 2 micrograms circle site-specific recombinase: implications for the double-strand-gap repair model.. https://doi.org/10.1128/mcb.6.11.3831-3837.1986

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