Project description:Theory and experiment suggest that organisms would benefit from pre-adaptation to future stressors based on reproducible environmental fluctuations experienced by their ancestors. Yet mechanisms driving pre-adaptation remain enigmatic. We report that the [SMAUG+] prion allows yeast to anticipate nutrient repletion after periods of starvation, providing a strong selective advantage. By transforming the landscape of post-transcriptional gene expression, [SMAUG+] regulates the decision between two broad growth and survival strategies: mitotic proliferation or meiotic differentiation into a stress-resistant state. [SMAUG+] is common in laboratory yeast strains, where standard propagation practice produces regular cycles of nutrient scarcity followed by repletion. Distinct [SMAUG+] variants are also widespread in wild yeast isolates from multiple niches, establishing that prion polymorphs can be utilized in natural populations. Our data provide a striking example of how protein-based epigenetic switches, hidden in plain sight, can establish a transgenerational memory that integrates adaptive prediction into developmental decisions.
Project description:Comparison between [gar-] and [GAR+] samples of the W303 background grown in 2% glucose. Three separate [gar-] and [GAR+] cultures were grown to late exponential phase (OD600~0.8) prior to phenol-chloroform extraction. Biological replicates are [gar-] samples #1, 2, and 3 and [GAR+] samples #1, 2, and 3. [gar-] and [GAR+] sample sets were compared to determine transcriptional differences.
Project description:Sfp1p is known to form the [ISP+] prion in Saccharomyces cerevisiae. Interestingly enough, the consequences and phenotypes of Sfp1p prionization and its absence are quite different. In order to understand the origin of this difference, we compared transcription profiles of an [ISP+], sfp1delta strains against the control strain (SFP1 [isp-]).
Project description:Reprogramming a non-methylotrophic industrial host, such as Saccharomyces cerevisiae, to a synthetic methylotroph reprents a huge challenge due to the complex regulation in yeast. Through TMC strategy together with ALE strategy, we completed a strict synthetic methylotrophic yeast that could use methanol as the sole carbon source. However, how cells respond to methanol and remodel cellular metabolic network on methanol were not clear. Therefore, genome-scale transcriptional analysis was performed to unravel the cellular reprograming mechanisms underlying the improved growth phenotype.
