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PubMed · 1846969

Single-step selection for Ty1 element retrotransposition.

M J Curcio·D J Garfinkel
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Abstract

The yeast retrotransposon Ty1 has been tagged with a reporter gene that allows selection of RNA-mediated transposition events and is applicable to the study of retroelements in other organisms. The reporter gene is a yeast HIS3 gene interrupted by an artificial intron (AI) in the antisense orientation. The HIS3AI sequences were inserted into a Ty1 element such that the intron is on the sense strand of the Ty1 element; therefore, splicing and retrotransposition of marked Ty1 transcripts can give rise to His+ cells. Fusion of the Ty1-H3mHIS3AI element to the inducible GAL1 promoter resulted in a high frequency of histidine prototrophs upon galactose induction. Moreover, spontaneous His+ revertants derived from strains containing genomic TymHIS3AI elements are a result of retrotransposition. By using this assay, we estimated the Ty1 transposition rate to be between 3 x 10(-7) and 1 x 10(-5) transpositions per Ty1 element per generation. Variations in the transposition rate of individual Ty1 elements are correlated with the relative abundance of their transcripts.

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Blotting, NorthernDNA Transposable ElementsGenes, FungalIntronsPhenotypePlasmidsRNA, FungalSaccharomyces cerevisiaeJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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M J Curcio, D J Garfinkel. 1991-02-01. Single-step selection for Ty1 element retrotransposition.. https://doi.org/10.1073/pnas.88.3.936

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