The study of epigenetic mechanism of ethanol tolerance genetic instability of yeast

Abstract:

The improved yeast strains obtained through classical breeding methods, such as the mutation and the acclimatization, easily lost their acquired characteristics during the process of passage or conservation. We investigated the epigenetic molecular mechanism of genetic instability about the yeast acquired traits. The relationship between the genetic stability of ethanol tolerance and the change of H3K4 methylation level of promoters of pro1, tps1, sod1 was studied in the process of yeast strain breeding for improving ethanol tolerance or passage of improved strains without ethanol stress. The results showed that the genetic stability of ethanol tolerance was regulated by epigenetic variation of some genes in the yeast. The genetic instability of acquired traits of yeast might result from its epigenetic variation of relative genes because many environmental factors influenced on the epigenetic molecular modification in cells.