The WTM genes in budding yeast amplify expression of the stress-inducible gene RNR3.
Cellular responses to DNA damage and inhibited replication are evolutionarily conserved sets of pathways that are critical to preserving genome stability. To identify new participants in these responses, we undertook a screen for regulators that, when present on a high-copy vector, alter expression of a DNA damage-inducible RNR3-lacZ reporter construct in Saccharomyces cerevisiae. From this screen we isolated a plasmid encoding two closely related paralogs, WTM1 and WTM2, that greatly increases constitutive expression of RNR3-lacZ. Moderate overexpression of both genes together, or high-level expression of WTM2 alone from a constitutive promoter, upregulates RNR3-lacZ in the absence of DNA damage. Overexpressed, tagged Wtm2p is associated with the RNR3 promoter, indicating that this effect is likely direct. Further investigation reveals that Wtm2p and Wtm1p, previously described as regulators of meiotic gene expression and transcriptional silencing, amplify transcriptional induction of RNR3 in response to replication stress and modulate expression of genes encoding other RNR subunits.
Tringe
Susannah Green
SG
Department of Molecular Genetics and Microbiology and Cancer Research and Treatment Center, University of New Mexico Health Sciences Center, Albuquerque, New Mexico 87131, USA.
Willis
Jason
J
Liberatore
Katie L
KL
Ruby
Stephanie W
SW
D047369:Chromatin Immunoprecipitation; D015966:Gene Expression Regulation, Fungal; D005800:Genes, Fungal; D010957:Plasmids; D012097:Repressor Proteins / Q000235:genetics*; D012264:Ribonucleotide Reductases / Q000235:genetics*; D012441:Saccharomyces cerevisiae / Q000201:enzymology / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics*; D014157:Transcription Factors / Q000235:genetics*; D001616:beta-Galactosidase / Q000032:analysis
D012097:Repressor Proteins; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors; C107277:Wtm1 protein, S cerevisiae; C107278:Wtm2 protein, S cerevisiae; D012264:Ribonucleotide Reductases; D001616:beta-Galactosidase