Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 1987 Jun;7(6):2212-20.
doi: 10.1128/mcb.7.6.2212-2220.1987.

Elements involved in oxygen regulation of the Saccharomyces cerevisiae CYC7 gene

R S Zitomer, J W Sellers, D W McCarter, G A Hastings, P Wick, C V Lowry

Elements involved in oxygen regulation of the Saccharomyces cerevisiae CYC7 gene

R S Zitomer et al. Mol Cell Biol. 1987 Jun.

Abstract

The CYC7 gene of Saccharomyces cerevisiae encodes the minor species, iso-2, of the cytochrome c protein. Its expression is governed by two regulatory sequences upstream from the gene: a positive site which stimulates transcription 240 base pairs 5' from the protein-coding sequence (-240) and a negative site which inhibits transcription at -300. In this study, the nature of the positive site and its relationship to the negative site has been investigated. Expression of the CYC7 gene is weakly inducible by oxygen. This effect was greatly enhanced by the semidominant CYP1-16 mutation in the trans-acting gene CYP1. The weak oxygen regulation in wild-type cells and the enhanced induction in CYP1-16 mutants were found to be mediated through the positive site. A mutational analysis of this site implicated at least part of a tandem, direct repeat of 9 base pairs as essential for the functioning of this site. The relationship between the positive and negative sites was investigated by comparing the expression of the intact gene with that of derivatives lacking either one or the other site. The expression of the gene containing only the negative site was actually stimulated anaerobically, while the gene containing the positive site alone, although having higher expression aerobically than anaerobically, had higher anaerobic expression than did the intact gene. Thus, it appeared that the combination of the positive and negative sites suppressed anaerobic expression. A model which attempts to explain these properties of the two sites and account for the regulation of the expression of the intact gene is presented.

PubMed Disclaimer

References

    1. J Biol Chem. 1982 Jul 10;257(13):7756-61 - PubMed
    1. Annu Rev Genet. 1971;5:257-96 - PubMed
    1. Gene. 1982 Oct;19(3):269-76 - PubMed
    1. Proc Natl Acad Sci U S A. 1982 Dec;79(23):7214-7 - PubMed
    1. Proc Natl Acad Sci U S A. 1966 Jun;55(6):1498-504 - PubMed

Publication types