Identification of the role of the HSP150 gene on the genotoxicity of zinc oxide nanoparticles in Saccharomyces cerevisae

Abstract

Nanoparticles can easily reach soil,water and foodstuffs. The zinc oxide nanoparticle (ZnONP), which is a type of nanoparticle with known antiviral/microbial properties used frequently in cosmetic UV protection products, can damage the cell membrane/wall complex in Saccharomyces cerevisiae after exposure. However, the capacity of hsp150, an o-mannosylated heat shock protein needed for the strength of the S. cerevisiae cell wall, to prevent ZnONP toxicity/genotoxicity has not been investigated before. In this study, HSP150 gene of S. cerevisiae cells was deleted and the effects on the toxicity caused by ZnONPs were investigated by MTT, cell wall/membrane damage analyses and zymolyase susceptibility test. In addition, the level of oxidative DNA damage was determined by 8-OHdG test in the HSP150 deficient cells (hsp150 Delta). IC50 values observed in hsp150 Delta cells were lower than the wild type cells. In addition, the lowest dose of ZnONPs (250 mu g/mL) was significant enough to damage the cellular integrity in hsp150 Delta cells and DNA damage levels observed in the hsp150 Delta cells exposed to the lowest dose of the nanoparticles were nearly 2.5 times higher than the wild type cells. Therefore, it can be concluded that the HSP150 gene is needed for the cellular protection against ZnONP toxicity and genotoxicity.