Gene Expression Analysis in Freshwater Mussels (Unio stevenianus) Collected from Pollutant-Associated Environment

Abstract

Common pollutants found in rivers include sewage, pesticides, heavy metals, nutrients from agricultural runoff, and pathogens. The resulting pollution can alter the physiological processes of living systems and cause environmental stress in aquatic environments. The need to monitor the effects of pollution in aquatic ecosystems has been driven by environmental and human health concerns. Freshwater mussels, which play an important role in freshwater ecosystems, are constantly exposed to a wide variety of contaminants as filter feeders. The sessile nature of mussels and their relatively long life span make them useful indicator species for monitoring and assessment of water quality. The aim of this study is to determine physiological stress in Unio stevenianus living in Karasu river, whose pollution level is increasing daily, by Cox gene expression. Real-time PCR analysis using β-actin as a reference gene was used for gene expression. The expression level of the Cox gene was higher in the Zeve region than in the Arısu region. The lower level in Arısu region indicates that water quality criteria are better in this region than in Zeve region. Expression studies should be carried out in U. stevenianus by selecting different genes specific to certain pollutants.