The identification and oxidative stress response of a zeta class glutathione S-transferase (GSTZ1) gene from Apis cerana cerana

Glutathione-S-transferases (GSTs) play an important role in protecting organisms against the toxicity of reactive oxygen species (ROS). However, no information is available for GSTs in the Chinese honey bee (Apis cerana cerana). In this study, we isolated and characterized a zeta class GST gene (AccGSTZ1) from the Chinese honey bee. This gene is present in a single copy and harbors five exons. The deduced amino acid sequence of AccGSTZ1 shared high sequence identity with homologous proteins and contained the highly conserved features of this gene family. The temporal and spatial expression profiles of AccGSTZ1 showed that AccGSTZ1 was highly expressed in fourth instar larvae during development, and the mRNA level of AccGSTZ1 was higher in the epidermis than that in other tissues. The expression pattern under oxidative stress revealed that AccGSTZ1 transcription was significantly upregulated by external factors, such as temperature challenges and H2O2 treatment. The characterization of the purified protein revealed that AccGSTZ1 had low glutathione-conjugating activity, but the recombinant AccGSTZ1 protein displayed high antioxidant activity under oxidative stress. These data suggest that AccGSTZ1 is an oxidative stress-inducible antioxidant enzyme that plays an important role in the protection against oxidative stress and may be of critical importance for the survival of the honey bees.