Stress response and expression patterns in wine fermentations of yeast genes induced at the diauxic shift
✍ Scribed by Puig, Sergi; P�rez-Ort�n, Jos� E.
- Publisher
- John Wiley and Sons
- Year
- 2000
- Tongue
- English
- Weight
- 233 KB
- Volume
- 16
- Category
- Article
- ISSN
- 0749-503X
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✦ Synopsis
During wine fermentation yeasts quickly reach a stationary phase, where cells are metabolically active by consuming sugars present in grape must. It is, consequently, of great interest at this stage to identify suitable gene promoters that may be used to induce the expression of genes with enological applications. With this aim, we have studied a group of genes showing an induction peak at the diauxic shift, and possessing stress response elements (STRE) at their promoters. We have determined their induction levels under individualized stress conditions, such as carbon source starvation or high salt concentrations. In all the cases studied, the activation and/or basal transcription are dependent on the transcriptional factors Msn2p and Msn4p. We have analysed the expression patterns and mRNA levels during wine fermentation, and have found that they are all activated at the stationary phase. Finally, we have identi®ed SPI1, a new highly expressed yeast gene which is speci®cally induced at the stationary phase of both microvini®cation and laboratory growth conditions.