Glutathione reductase, a biomarker of pollutant and stress in Pacific abalone

Abalone are frequently exposed to several environmental factors including heavy metal toxicity, thermal stress, H2O2-stress, starvation, viral and bacterial infection that can induce oxidative stress. Glutathione reductase is a vital enzyme in the antioxidant defense system that catalyzes the reduction of oxidized glutathione to reduced glutathione. The present study aimed to identify and localize glutathione reductase in Pacific abalone (Hdh-GR) and assess its potential role in stress physiology, heavy metal toxicity, immune response, gonadal development, and metamorphosis. The mRNA expression of Hdh-GR was upregulated in response to thermal stress, starvation, H2O2-stress, and cadmium-exposed toxicity. The induced mRNA expression was also quantified in immune-challenged abalone. Moreover, the Hdh-GR expression was significantly higher during metamorphosis. The Hdh-GR mRNA expression showed an inverse relationship with ROS production in heat stressed Pacific abalone. These results suggest that Hdh-GR has central role in the stress physiology, immune response, gonadal development, and metamorphosis of Pacific abalone. [Display omitted] •Hdh-GR, a biomarker gene was characterized from Pacific abalone.•Fluorescence in-situ hybridization confirmed the localization of Hdh-GR in DG.•Heavy metal (Cd) toxicity, ROS-induction (H2O2), and thermal stress induces Hdh-GR expression.•Virus infection, bacterial infection, and starvation also induces Hdh-GR expression.•Hdh-GR may have defensive role against excessive ROS production.