| Human DJ-1 (HsDJ-1) is a well-known protein, associated with the early-onset Parkinson’s disease (PD) and some cancers. In the fission yeast Schizosaccharomyces pombe, there are one SpDJ-1 which is the most closely related homolog of DJ-1 and five Hsp31 proteins (Hsp3101, Hsp3102, Hsp3103, Hsp3104, Hsp3105) which are weakly homologous to it. DJ-1 and its homologs have been primarily implicated in oxidative stress in various species, however, the case in S. pombe and the mechanism of how HsDJ-1 executes the function remains to be determined.In this study, we focus on the issues of determining the subcellular localizations of protein SpDJ-1 and Hsp31 under the different promoters, the expression level during their different growth periods, the function of SpDJ-1 in protecting cells from oxidative stress, and make a preliminary study about its mechanism.Firstly, we examined the localization of the C-terminal GFP fusions of SpDJ-1 and Hsp3101-3105. We found that under the control of the intermediate-strength nmtl promoter, SpDJ-1, Hsp3101, Hsp3105 are localized in the nucleus and cytoplasm, Hsp3102 and Hsp3104 is only localized in the cytoplasm. While under the control of their own promoters, SpDJ-1 and Hsp3101 are localized in the nucleus and cytoplasm, Hsp3102 is only localized in the cytoplasm, not in nucleus. Results show that those homologous proteins are localized in different organelles which indicates that their functions maybe different. Secondly, through the method of western blot, we found that all those proteins’expression level was gradually increased from the logarithmic phase to the steady state, and then remained unchanged, indicate ing that these proteins may function at the stable phage. In the last, we dectected the response of the yeast in which SpDJ-1 was knock-out or overexpressed to the oxidative stress induced by the reagents called TBHP and H2O2 or to the thermal stimulus, we affirmed the effect of SpDJ-1 of protecting cells from stresses.
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