Editor: Hyun Kang
Identification and classification of genes required for tolerance to freeze–thaw stress revealed by genome-wide screening of Saccharomyces cerevisiae deletion strains
Article first published online: 21 SEP 2006
FEMS Yeast Research
Volume 7, Issue 2, pages 244–253, March 2007
How to Cite
Ando, A., Nakamura, T., Murata, Y., Takagi, H. and Shima, J. (2007), Identification and classification of genes required for tolerance to freeze–thaw stress revealed by genome-wide screening of Saccharomyces cerevisiae deletion strains. FEMS Yeast Research, 7: 244–253. doi: 10.1111/j.1567-1364.2006.00162.x
- Issue published online: 21 SEP 2006
- Article first published online: 21 SEP 2006
- Received 17 April 2006; revised 11 July 2006; accepted 20 July 2006.First published online 21 September 2006.
- baker's yeast;
- freeze–thaw stress;
- bread baking;
- yeast deletion mutant collection
Yeasts used in bread making are exposed to freeze–thaw stress during frozen-dough baking. To clarify the genes required for freeze–thaw tolerance, genome-wide screening was performed using the complete deletion strain collection of diploid Saccharomyces cerevisiae. The screening identified 58 gene deletions that conferred freeze–thaw sensitivity. These genes were then classified based on their cellular function and on the localization of their products. The results showed that the genes required for freeze–thaw tolerance were frequently involved in vacuole functions and cell wall biogenesis. The highest numbers of gene products were components of vacuolar H+-ATPase. Next, the cross-sensitivity of the freeze–thaw-sensitive mutants to oxidative stress and to cell wall stress was studied; both of these are environmental stresses closely related to freeze–thaw stress. The results showed that defects in the functions of vacuolar H+-ATPase conferred sensitivity to oxidative stress and to cell wall stress. In contrast, defects in gene products involved in cell wall assembly conferred sensitivity to cell wall stress but not to oxidative stress. Our results suggest the presence of at least two different mechanisms of freeze–thaw injury: oxidative stress generated during the freeze–thaw process, and defects in cell wall assembly.