Regulation of RAD54- and RAD52-lacZ gene fusions in Saccharomyces cerevisiae in response to DNA damage.
AUTOR(ES)
Cole, G M
RESUMO
The RAD52 and RAD54 genes in the yeast Saccharomyces cerevisiae are involved in both DNA repair and DNA recombination. RAD54 has recently been shown to be inducible by X-rays, while RAD52 is not. To further investigate the regulation of these genes, we constructed gene fusions using 5' regions upstream of the RAD52 and RAD54 genes and a 3'-terminal fragment of the Escherichia coli beta-galactosidase gene. Yeast transformants with either an integrated or an autonomously replicating plasmid containing these fusions expressed beta-galactosidase activity constitutively. In addition, the RAD54 gene fusion was inducible in both haploid and diploid cells in response to the DNA-damaging agents X-rays, UV light, and methyl methanesulfonate, but not in response to heat shock. The RAD52-lacZ gene fusion showed little or no induction in response to X-ray or UV radiation nor methyl methanesulfonate. Typical induction levels for RAD54 in cells exposed to such agents were from 3- to 12-fold, in good agreement with previous mRNA analyses. When MATa cells were arrested in G1 with alpha-factor, RAD54 was still inducible after DNA damage, indicating that the observed induction is independent of the cell cycle. Using a yeast vector containing the EcoRI structural gene fused to the GAL1 promoter, we showed that double-strand breaks alone are sufficient in vivo for induction of RAD54.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=365179Documentos Relacionados
- Regulation of HIS4-lacZ fusions in Saccharomyces cerevisiae.
- Fusion of Escherichia coli lacZ to the cytochrome c gene of Saccharomyces cerevisiae.
- Use of lacZ fusions to delimit regulatory elements of the inducible divergent GAL1-GAL10 promoter in Saccharomyces cerevisiae.
- Retrovirus promoter-trap vector to induce lacZ gene fusions in mammalian cells.
- Gene fusions to lacZ reveal new expression patterns of chimeric genes in transgenic plants.