Analysis of the hypoxia-induced ADH2-promoter of the respiratory yeast Pichia stipitis reveals a new mechanism for sensing of oxygen limitation in yeast

Summary, in English

We introduced a reporter gene system into Pichia stipitis using the gene for the artificial green fluorescent protein (GFP), variant yEGFP. This system was used to analyse hypoxia-dependent PsADH2 regulation. Reporter gene activity was only found under oxygen limitation on a fermentable carbon source. The promoter was not induced by oxygen limitation in the Crabtree-positive yeast Saccharomyces cerevisiae. Promoter deletions revealed that a region of 15 bp contained the essential site for hypoxic induction. This motif was different from the known hypoxia response elements of S. cerevisiae but showed some similarity to the mammalian HIF-1 binding site. Electrophoretic mobility shift assays demonstrated specific protein binding to this region under oxygen limitation. Similar to the S. cerevisiae heme sensor system, the promoter was induced by Co2+. Cyanide was not able to mimic the effect of oxygen limitation. The activation mechanism of PsADH2 also, in this respect, has similarities to the mammalian HIF-1 system, which is inducible by Co2+ but not by cyanide. Thus, the very first promoter analysis in P. stipitis revealed a hitherto unknown mechanism of oxygen sensing in yeast.

• Author: Volkmar Passoth; Marita Cohn; B. Schäfer; Bärbel Hahn-Hägerdal; U. Klinner
• Department/s: Molecular Cell Biology; Applied Microbiology; Molecular Genetics and Genetics
• Publishing year: 2003
• Language: English
• Pages: 39-51
• Publication/Series: Yeast
• Volume: 20
• Issue: 1
• Links: http://dx.doi.org/10.1002/yea.933
• Document type: Journal article
• Publisher: John Wiley & Sons Inc.
• Topic: Biological Sciences; Industrial Biotechnology
• Keywords: hypoxia; green fluorescent; alcohol dehydrogenase; promoter analysis; protein; oxygen limitation
• Status: Published
• Research group: Molecular Genetics and Genetics
• ISBN/ISSN/Other: ISSN: 1097-0061