Effect of temperature on antioxidant enzyme activities and gene expression in sand worm Perinereis quatrefagesi (Grube, 1878)

Abstract

Polychaetes is one of intertidal animals that face the fluctuations of coastal environment through time. One of important environmental factors to animals is temperature regarding to the fluctuation of temperature in intertidal environment. Human activities could also cause high changes in water temperature by high temperature discharges from urban and industries. Since global warming is still a main issue, an increase of seawater temperature about 3°C could be possible as a prediction. This study aimed to investigate effect of temperature in polychaetes Perinereis quatrefagesi at cellular level, which could be indicated by heat shock response and oxidative stress due to function of basic stress. Responses in the worms at the cellular level were measured using real-time PCR for oxidative stress gene expression and using enzyme assay for protein activities. Different temperatures (27, 29, 31, 33°C) with three replication and different exposure times (0 d, 12 hrs, 1 d, 3 d, 7 d, 14 d, and 28 d) were designed. Results of growth parameters showed a significant change in the final wet weight regarding the different temperature levels. While survival rates and specific growth rates gave a similar pattern with a significant difference at the highest temperature. This growth parameters, therefore, revealed the optimal temperature for culture this species at 29°C, while 27°C and 31°C were also acceptable with regard to the high survival rate. For gene expression, the highest upregulation of hsp70, hsp90, sod, and catalase expressed at 33°C. High rate of upregulation was found at the first 12 hours on all gene, except sod which was non-detectable. An increasing trend of hsp70 with temperatures was a significant difference at the first 12 hours exposure. For enzyme activity, SOD activity showed an increasing trend at the first 12 hours exposure and a decreasing trend at 12 hours later, while the highest peak of SOD activity was found at the end of the experiment for all treatment. The CAT activity demonstrated a significant rise in the first 12 hours. Overall, this study supports the negative effect of high temperatures on aquatic organism in term of significantly low growth parameter and active stress responses; heat shock proteins and antioxidant enzymes, especially at the first 12-24 hours exposure.