A new regulatory element mediates ethanol repression of KlADH3, a Kluyveromyces lactis gene coding for a mitochondrial alcohol dehydrogenase.
KlADH3 is a Kluyveromyces lactis alcohol dehydrogenase gene induced in the presence of all respiratory carbon sources except ethanol, which specifically represses this gene. Deletion analysis of the KlADH3 promoter revealed the presence of both positive and negative elements. However, by site-directed mutagenesis and gel retardation experiments, we identified a 15-bp element responsible for the transcriptional repression of this gene by ethanol. In particular, this element showed putative sites required for the sequential binding of ethanol-induced factors responsible for the repressed conditions, and the binding of additional factors relieved repression. In addition, we showed that the ethanol element was required for in vivo repression of KlAdh3 activity.
Saliola
Michele
M
Department of Cell and Developmental Biology, University of Rome 'La Sapienza', Piazzale Aldo Moro, Rome, Italy. michele.saliola@uniroma1.it
Getuli
Claudia
C
Mazzoni
Cristina
C
Fantozzi
Ivana
I
Falcone
Claudio
C
D000426:Alcohol Dehydrogenase / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D003470:Culture Media; D004742:Enhancer Elements, Genetic / Q000235:genetics; D000431:Ethanol / Q000494:pharmacology*; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism; D017353:Gene Deletion; D015966:Gene Expression Regulation, Fungal; D007716:Kluyveromyces / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D008928:Mitochondria / Q000201:enzymology; D024101:Mitochondrial Proteins / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D011401:Promoter Regions, Genetic
D003470:Culture Media; D005656:Fungal Proteins; D024101:Mitochondrial Proteins; D000431:Ethanol; D000426:Alcohol Dehydrogenase