Functional Genomic Analysis of Wine Yeast

A similar study, profiling transcripts of ECU 18 using the same syn- 

Since SAGE was used, this study was able to quantify messages not 

One of the major areas of research interest in wine strains of S. cerevisiae is the analysis of response to stress. This focus is motivated by both practical and fimdamental interests. The production of wine imposes both biotic and abiotic stresses on the yeast. The principal stresses encountered are high osmolarity, high ethanol, extremes of temperature, nutrient limitation, and presence of inhibitory metabolites (Bisson, 1999). Genomic analysis of the response to each of these types of stress has been conducted (Alexandre et al., 2001 Aranda and del Olmo, 2004 Backhus et al., 2001 Erasmus et al., 2003 Kuhn et al., 2001 Marks et al., 2003 Rep et al., 2000 Rossignol et al., 2006 Sahara et al., 2002). Several 

FIGURE 4 Cyclical nature of the adaptation to stress during wine fermentation. Cells 

In wine strains, the response to increasing ethanol is quite complex. This is because ethanol rarely increases in the absence of other stress factors, such as nutrient limitation, and is accompanied by acetaldehyde production which is itself a stress factor (Aranda and del Olmo, 2004). Short-term ethanol stress has been evaluated in an attempt to dissect the responses specific to this compoimd (Alexandre et al., 2001). Approximately 3.1% of the transcripts analyzed increased in expression in response to exposure to ethanol. Of these genes, 49.4% belong to the ESR genes however, this represents only 73 of the 300 known ESR genes. 

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