Search bioRxivSearch

Biology subjects

Schnepper, A. P.

Publications and source records attributed to Schnepper, A. P..

3 recordsLinked to original sources

The ethanol tolerance in Saccharomyces cerevisiae under a phenomics perspective

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.

systems biology

LncRNAs of Saccharomyces cerevisiae dodge the cell cycle arrest imposed by the ethanol stress

Ethanol impairs many subsystems of Saccharomyces cerevisiae, including the cell cycle. Cyclins and damage checkpoints drive the cell cycle. Two ethanol-responsive lncRNAs in yeast interact with cell cycle proteins, and here we investigated the role of these RNAs on the ethanol-stressed cell cycle. Our network dynamic modeling showed that the higher and lower ethanol tolerant strains undergo a cell cycle arrest during the ethanol stress. However, lower tolerant phenotype arrest in a later phase leading to its faster population rebound after the stress relief. Two lncRNAs can skip the arrests mentioned. The in silico overexpression of lnc9136 of SEY6210 (a lower tolerant strain), and CRISPR-Cas9 partial deletions of this lncRNA, evidenced that the one induces a regular cell cycle even under ethanol stress; this lncRNA binds to Gin4 and Hsl1, driving the Swe1p, Clb1/2, and cell cycle. Moreover, the lnc10883 of BY4742 (a higher tolerant strain) interacts to the Mec1p and represses Bub1p, circumventing the DNA and spindle damage checkpoints keeping a normal cell cycle even under DNA damage. Overall, we present the first evidence of the direct roles of lncRNAs on cell cycle proteins, the dynamics of this system in different ethanol tolerant phenotypes, and a new cell cycle model.

systems biology

Long non-coding RNAs bind to proteins relevant to the ethanol tolerance in yeast: a systems biology view

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.

microbiology