A carbon-source-responsive element is required for regulation of the hypoxic ADP/ATP carrier (AAC3) isoform in Saccharomyces cerevisiae.
The mitochondrial ADP/ATP carrier in Saccharomyces cerevisiae is encoded by three genes that are differentially expressed under different physiological conditions. We investigated the transcriptional control of AAC3, an oxygen-repressed isoform. By deletion analysis, DNA electrophoretic mobility-shift assays, DNase I footprinting and site-directed mutagenesis, we have identified a promoter region (upstream repressing sequence 1, URS(1)) involved in a carbon-source-dependent repression of AAC3. It is different from the previously characterized oxygen-dependent ROX1 (regulation by oxygen 1) repressor-binding region (URS(2)). The complex character of URS(1) includes the presence of two different cis-acting sequences: (i) a RAP1 (repressor activator protein 1)-binding site that is capable of binding the RAP1 protein in vitro and (ii) two putative ethanol-repression sequences, the modification of which derepresses the AAC3 gene. These findings demonstrate that the hypoxic AAC3 gene is regulated by two upstream repressor sites; one controlled by oxygen and haem, the other by the carbon source. Both sites function to completely switch off the expression of the AAC3 isoform when ATP is made by oxidative phosphorylation, and they modulate AAC3 expression when import of glycolytic ATP into mitochondria is required.
Sokolíková
B
B
Department of Molecular Biology, Cancer Research Institute, Slovak Academy of Sciences, Vlarska 7, 833 91 Bratislava, Slovakia.
Sabová
L
L
Kissová
I
I
Kolarov
J
J
D001483:Base Sequence; D001665:Binding Sites; D002244:Carbon / Q000494:pharmacology*; D018983:DNA Footprinting; D004271:DNA, Fungal / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D003850:Deoxyribonuclease I / Q000378:metabolism; D000431:Ethanol / Q000378:metabolism / Q000494:pharmacology; D005656:Fungal Proteins / Q000378:metabolism; D015966:Gene Expression Regulation, Fungal / Q000187:drug effects*; D005800:Genes, Fungal / Q000235:genetics; D017930:Genes, Reporter / Q000235:genetics; D007527:Isoenzymes / Q000235:genetics; D008928:Mitochondria / Q000201:enzymology; D000226:Mitochondrial ADP, ATP Translocases / Q000235:genetics*; D009154:Mutation / Q000235:genetics; D011401:Promoter Regions, Genetic / Q000235:genetics; D011485:Protein Binding; D012097:Repressor Proteins / Q000235:genetics / Q000502:physiology; D020218:Response Elements / Q000235:genetics*; D012441:Saccharomyces cerevisiae / Q000187:drug effects / Q000201:enzymology / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins
D004271:DNA, Fungal; D004268:DNA-Binding Proteins; D005656:Fungal Proteins; D007527:Isoenzymes; C083348:ROX1 protein, S cerevisiae; D012097:Repressor Proteins; D029701:Saccharomyces cerevisiae Proteins; D000431:Ethanol; D002244:Carbon; D000226:Mitochondrial ADP, ATP Translocases; D003850:Deoxyribonuclease I