Disruption of YCP4 enhances freeze-thaw tolerance in Saccharomyces cerevisiae.

Hyun-Soo Kim

doi:10.1007/s10529-022-03228-z

Abstract

This study aimed to identify genes related to freeze-thaw tolerance and elucidate the tolerance mechanism in yeast Saccharomyces cerevisiae as an appropriate eukaryote model. In this study, one tolerant strain exposed to freeze-thaw stress was isolated by screening a transposon-mediated mutant library and the disrupted gene was identified to be YCP4. In addition, this phenotype related to freeze-thaw tolerance was confirmed by deletion and overexpressing of this corresponding gene. This mutant strain showed a freeze-thaw tolerance by reducing the intracellular level of reactive oxygen species and the activation of the MSN2/4 and STRE-mediated genes such as CTT1 and HSP12. Disruption of YCP4 in S. cerevisiae results in increased tolerance to freeze-thaw stress.

Highlights

Freezing and thawing is a type of stress that can cause serious physiological injury to cells, including cell wall and cell membrane damage, DNA and protein degeneration, due to the formation of ice crystals and cell dehydration (Hsu et al 1979; Mazur 1970)
The response of cells to freezing and thawing stress is not known in detail, it is generally accepted that freeze-thaw tolerance is related to factors including growth phase (Werner-Washburne et al 1993), respiratory metabolism (Lewis et al/ 1993), and lipid composition of the membrane (Gélinas et al 1991)
The yeast Saccharomyces cerevisiae become more resistant to freeze-thaw stress by adding glycerol (Izawa et al 2004) and accumulation of trehalose as cryoprotectants (Nakamura et al 2009), the mechanisms underlying freeze-thaw tolerance has not been completely understtod in the eukaryotes

Summary

Results

One tolerant strain under exposure to freeze-thaw stress was isolated by screening a transposon-mediated mutant library and the disrupted gene was identified to be YCP4. This phenotype related to freeze-thaw tolerance was comfirmed by deletion and overexpressing of this corresponding gene. This mutant strain showed a freeze-thaw tolerance by the reduction in the intracellular level of reactive oxygen species (ROS) and the activation of the MSN2/4 and STRE-mediated genes such as CTT1 and HSP12

Introduction

Materials And Methods

Results And Discussion