Ethanol (EtOH) alters many cellular processes in yeast. An integrated view of different EtOH-tolerant phenotypes and their long noncoding RNAs (lncRNAs) is not yet available. Here, large-scale data integration showed the core EtOH-responsive pathways, lncRNAs, and triggers of higher (HT) and lower (LT) EtOH-tolerant phenotypes. LncRNAs act in a strain-specific manner in the EtOH stress response. Network and omics analyses revealed that cells prepare for stress relief by favoring activation of life-essential systems. Therefore, longevity, peroxisomal, energy, lipid, and RNA/protein metabolisms are the core processes that drive EtOH tolerance. By integrating omics, network analysis, and several other experiments, we showed how the HT and LT phenotypes may arise: (1) the divergence occurs after cell signaling reaches the longevity and peroxisomal pathways, with CTA1 and ROS playing key roles; (2) signals reaching essential ribosomal and RNA pathways via SUI2 enhance the divergence; (3) specific lipid metabolism pathways also act on phenotype-specific profiles; (4) HTs take greater advantage of degradation and membraneless structures to cope with EtOH stress; and (5) our EtOH stress-buffering model suggests that diauxic shift drives EtOH buffering through an energy burst, mainly in HTs. Finally, critical genes, pathways, and the first models including lncRNAs to describe nuances of EtOH tolerance are reported here.

The ethanol disturbs the cell cycle, transcription, translation, protein folding, cell wall, membranes, and many Saccharomyces cerevisiae metabolic processes. Long non-coding RNAs (lncRNAs) are regulatory molecules binding onto the genome or proteins. The number of lncRNAs described for yeast is still scarce, and little is known concerning their roles in the system. There is a lack of knowledge concerning how lncRNAs are responsive to the ethanol tolerance in yeast and whether they act in this tolerance. Hence, by using RNA-Seq data from S. cerevisiae strains with different ethanol tolerance phenotypes, we found the severe ethanol responsive lncRNAs. We modeled how they participate in the ethanol tolerance by analyzing lncRNA-protein interactions. The results showed that the EtOH tolerance responsive lncRNAs, in both higher tolerant and lower tolerant phenotypes, work on different pathways: cell wall, cell cycle, growth, longevity, cell surveillance, ribosome biogenesis, intracellular transport, trehalose metabolism, transcription, and nutrient shifts. In summary, lncRNAs seems to interconnect essential systems’ modules to overcome the ethanol stress. Finally, here we also found the most extensive catalog of lncRNAs in yeast.

Ethanol (EtOH) is a substantial stressor for Saccharomyces cerevisiae . Data integration from strains with different phenotypes, including EtOH stress-responsive lncRNAs, are still not available. We covered these issues seeking systems modifications that drive the divergences between higher (HT) and lower (LT) EtOH tolerant strains under their highest stress conditions. We showed that these phenotypes are neither related to high viability nor faster population rebound after stress relief. LncRNAs work on many stress-responsive systems in a strain-specific manner promoting the EtOH tolerance. Cells use membraneless RNA/protein storage and degradation systems to endure the stress harming, and lncRNAs jointly promote EtOH tolerance. CTA1 and longevity are primer systems promoting phenotype-specific gene expression. The lower cell viability and growth under stress is a byproduct of sphingolipids and inositol phosphorylceramide dampening, acerbated in HTs by sphinganine, ERG9, and squalene overloads; LTs diminish this harm by accumulating inositol 1-phosphate. The diauxic shift drives an EtOH buffering by promoting an energy burst under stress, mainly in HTs. Analysis of mutants showed genes and lncRNAs in three strains critical for their EtOH tolerance. Finally, longevity, peroxisome, energy and lipid metabolisms, RNA/protein degradation and storage systems are the main pathways driving the EtOH tolerance phenotypes.