Carbon source influences Saccharomyces cerevisiae yeast cell survival strategies: quiescence or sporulation

When starving, diploid Saccharomyces cerevisiae yeasts can enter into at least two stable non-dividing states - sporulation or quiescence - and thus survive unfavorable conditions for long periods of time. However, which latent state will be preferred depends on numerous conditions. Here, we showed that budding yeasts can trigger transition into one or the other dormant state depending on the carbon source utilized. When fermentable carbon source (glucose) is present in the growth medium, the diploid S. cerevisiae entered quiescence. On the other hand, when cells were grown in the presence of the energy-rich respiratory carbon source ethanol, yeasts preferably formed ascospores. In both latent states a steady redox balance is maintained. Altogether, these findings strongly suggest that survival strategies in yeasts S. cerevisiae and transition into distinct differentiation programs depend on the cellular metabolic status.