When yeast cells are inoculated into grape must for vinification they find stress conditions because of osmolarity, which is due to very high sugar concentration, and pH lower than 4. In this work an analysis of the expression of three osmotic stress induced genes (GPD1, HSP12 and HSP104) under microvinification conditions is shown as a way to probe those stress situations and the regulatory mechanisms that control them. The results indicate that during the first hours of microvinification there is an increase in the GPDI mRNA levels with a maximum about one hour after inoculation, and a decrease in the amount of HSP12 and HSP104 mRNAs, although with differences between them. The RNA steady-state levels of all the genes considered, and in some cases the microvinification progress are significantly affected by the composition of the must (pH, nature of the osmotic agent and carbon source). These results point out the importance of the control of these parameters and the yeast molecular response during the first hours of vinification for an accurate winemaking process.

中文翻译：

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通过使用渗透胁迫反应基因作为探针进行微葡萄收获期的最初几个小时的研究。

当将酵母细胞接种到葡萄中进行酿酒时，它们会由于渗透压而发现压力条件，因为渗透压是由于糖浓度很高，pH值低于4。在这项工作中，我们分析了三种渗透压诱导基因（GPD1， HSP12和HSP104）在微酿酒条件下被显示为探测那些压力情况和控制它们的调节机制。结果表明，在微接种的最初几个小时内，接种后约一小时，GPDI mRNA的水平最高，而HSP12和HSP104 mRNA的量却有所下降，尽管两者之间存在差异。所考虑的所有基因的RNA稳态水平，在某些情况下，微量葡萄酿酒的进程会受到必需液成分（pH，渗透剂和碳源的性质）。这些结果指出了在精确的酿酒过程中，在酿造的最初几个小时中控制这些参数和酵母分子反应的重要性。