Abstract
In Saccharomyces cerevisiae the anaerobic (oxygen-repressed) ANB1 gene and a group of aerobic (oxygen-induced) genes are coordinately regulated by the ROX1 gene. We report here that heme, known as an inducer of aerobic genes, also causes inhibition of ANB1 expression. Thus, in combination with the ROX1 gene product heme has an opposite effect on the expression of anaerobic and aerobic genes. Accumulation of ANB1 mRNA was sharply decreased in anaerobic cells grown in the presence of heme. This effect must operate at the level of transcription since heme also inhibited accumulation of CYC1 mRNA from an ANB1-CYC1 fusion. Heme precursors did not appear to function either as inhibitors or as activators. Oxygen itself also had no effect on transcription of ANB1. Repression by heme cannot be attributed to the respiratory competence conferred by heme since both ANB1 and the aerobic genes tr-1 and CYC1 were regulated normally in [rho 0] mutants. The results are consistent with a classical allosteric coeffector function for heme, although more indirect explanations are tenable. A role for the ROX1 gene product in transcriptional regulation can be inferred from the observation that there was no inhibition of ANB1 expression by heme in rox1 mutants. Judging from this epistasis the rox1 phenotype is not due to a defect in heme production; this would indicate that the ROX1 factor functions by mediating the effect of heme on transcription.
Full text
PDF



Images in this article
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Davidson E. H., Jacobs H. T., Britten R. J. Very short repeats and coordinate induction of genes. Nature. 1983 Feb 10;301(5900):468–470. doi: 10.1038/301468a0. [DOI] [PubMed] [Google Scholar]
- Gollub E. G., Liu K. P., Dayan J., Adlersberg M., Sprinson D. B. Yeast mutants deficient in heme biosynthesis and a heme mutant additionally blocked in cyclization of 2,3-oxidosqualene. J Biol Chem. 1977 May 10;252(9):2846–2854. [PubMed] [Google Scholar]
- Greenblatt J., Schleif R. Arabinose C protein: regulation of the arabinose operon in vitro. Nat New Biol. 1971 Oct 6;233(40):166–170. doi: 10.1038/newbio233166a0. [DOI] [PubMed] [Google Scholar]
- Guarente L., Lalonde B., Gifford P., Alani E. Distinctly regulated tandem upstream activation sites mediate catabolite repression of the CYC1 gene of S. cerevisiae. Cell. 1984 Feb;36(2):503–511. doi: 10.1016/0092-8674(84)90243-5. [DOI] [PubMed] [Google Scholar]
- Guarente L., Mason T. Heme regulates transcription of the CYC1 gene of S. cerevisiae via an upstream activation site. Cell. 1983 Apr;32(4):1279–1286. doi: 10.1016/0092-8674(83)90309-4. [DOI] [PubMed] [Google Scholar]
- Lowry C. V., Weiss J. L., Walthall D. A., Zitomer R. S. Modulator sequences mediate oxygen regulation of CYC1 and a neighboring gene in yeast. Proc Natl Acad Sci U S A. 1983 Jan;80(1):151–155. doi: 10.1073/pnas.80.1.151. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lowry C. V., Zitomer R. S. Oxygen regulation of anaerobic and aerobic genes mediated by a common factor in yeast. Proc Natl Acad Sci U S A. 1984 Oct;81(19):6129–6133. doi: 10.1073/pnas.81.19.6129. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Richter K., Ammerer G., Hartter E., Ruis H. The effect of delta-aminolevulinate on catalase T-messenger RNA levels in delta-aminolevulinate synthase-defective mutants of Saccharomyces cerevisiae. J Biol Chem. 1980 Sep 10;255(17):8019–8022. [PubMed] [Google Scholar]
- Saltzgaber-Müller J., Schatz G. Heme is necessary for the accumulation and assembly of cytochrome c oxidase subunits in Saccharomyces cerevisiae. J Biol Chem. 1978 Jan 10;253(1):305–310. [PubMed] [Google Scholar]
- Struhl K., Stinchcomb D. T., Scherer S., Davis R. W. High-frequency transformation of yeast: autonomous replication of hybrid DNA molecules. Proc Natl Acad Sci U S A. 1979 Mar;76(3):1035–1039. doi: 10.1073/pnas.76.3.1035. [DOI] [PMC free article] [PubMed] [Google Scholar]