title: Overexpression of PDE2 or SSD1-V in Saccharomyces cerevisiae W303-1A strain renders it ethanol-tolerant.
abstract: Understanding the genetic basis of the yeast ability to proliferate and ferment in the presence of restrictive concentrations of ethanol is of importance to both science and technology. In this study, we searched for genes that improve ethanol tolerance in ethanol-sensitive strains. To screen for suppressors of ethanol sensitivity, we introduced a 2µ-based genomic library, prepared from the ethanol-tolerant yeast S288C, into the ethanol-sensitive strain W303-1A. Two genomic fragments from this library rescued the ethanol sensitivity of W303-1A. One contained the PDE2 gene, which when over-expressed, conferred ethanol tolerance. Surprisingly, the effect of PDE2 was not mediated via MSN2/MSN4 transcription factors, as it was able to improve ethanol tolerance in msn2Δmsn4Δ strain. In the second genomic fragment, it was the N-terminal region of the SSD1 gene that carried the ethanol-tolerant phenotype. The SSD1-V allele of the polymorphic SSD1 gene expressed from a low-copy number plasmid also resulted in the tolerant phenotype. Both SSD1 and PDE2 seemed to improve ethanol tolerance by maintaining robustness of the yeast cell wall.
authors.affiliation: Department of Biological Chemistry, Institute of Life Sciences, Hebrew University of Jerusalem, Jerusalem, Israel.
authors.forename: Liat
authors.initials: L
authors.lastname: Avrahami-Moyal
authors.forename: Sergei
authors.initials: S
authors.lastname: Braun
authors.forename: David
authors.initials: D
authors.lastname: Engelberg
mesh_terms: D002473:Cell Wall / Q000502:physiology; D054678:Cyclic Nucleotide Phosphodiesterases, Type 2 / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D000431:Ethanol / Q000378:metabolism / Q000633:toxicity*; D005285:Fermentation; D015870:Gene Expression; D010957:Plasmids; D012441:Saccharomyces cerevisiae / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D029701:Saccharomyces cerevisiae Proteins / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism
chemical_list: D029701:Saccharomyces cerevisiae Proteins; C485219:Ssd1 protein, S cerevisiae; D000431:Ethanol; D054678:Cyclic Nucleotide Phosphodiesterases, Type 2