Abstract:

In order to explore the role of protein kinase TOS3 in signal pathway of response to nutrient stress in Saccharomyces cerevisiae, the ORF of TOS3 was amplified by PCR, and TOS3 was cloned into multicopy expression vector pYES2/NTA to construct recombinant expression plasmid pYES2/NTA-TOS3, the recombinant plasmid was transformed into yeast cells and this cell was TOS3 overexpression cells. This yeast cells were induced to overexpress TOS3 protein with His6 tag. The fusion protein tagged with His6 was identified by Western blot. Finally, TOS3 overexpression cell, TOS3 deletion mutant, wide type cell and wide type cell with load vector were treated with H2O2. The results showed: there was no difference between the growth states of four kinds cells before treatment; after treatment of H2O2, at 125 time dilution sport, the growth state of wide type cell was a little better than TOS3 deletion mutant, and the growth state of TOS3 overexpression cell was better than wide type cell and wide type cell with load vector. The tolerance of wide type cell to H2O2 stress was stronger than TOS3 dilution mutant; and the tolerance of TOS3 overexpression cell was stronger than wide type cell under oxidative stress treatment, this indicated that TOS3 could regulate oxidative stress response positively.