Metallothioneines and Hsp70 as biomarkers of cadmium contamination in aquatic organisms

In order to evaluate exposure to a polluant and/or the deleterious efects of a pollutant on organisms, biomarkers are increasingly used. Among these, stress proteins of the 70 type (Hsp 70) and metallothioneins (MTs) are by far the molecules that offer the widest spectrum of applications for biomonitoring of heavy metal pollution, in particular cadmium, a pollutant very common in the environment. However, a few questions remain when these biomarkers are used on organisms in toto. In order to better understand the mechanisms inducing these proteins, their distribution and roles in aquatic organisms, our laboratory analyses the effects of Cd2+ on the synthesis of MTs and Hsp70 in various types of tissues isolated from the euryhaline crab, Eriocheir sinensis.