Stress Protein Profile of Pesticide Exposed Fish

Abstract

Response to stress is well documented in many different biological systems. A common feature of this response at the molecular level is the induction of a set of proteins, which were first named heat- shock proteins (HSPs). These proteins are involved in the protection, enhanced survival and restoration of normal activities of stressed cells. Present study evaluated stress protein response of Etroplus suratensis exposed to pesticide, endosulfan. Specimens were collected from Vembanadu Lake. Pesticide tested was endosulfan (OC). Protein profiles of the gills, liver and muscle of controlled and exposed fish were analysed by SDS-PAGE technique. The result revealed considerable differences in the protein profiles of the gills, liver and muscle of both controlled and exposed fish. In the exposed fish noticeable stress response was detected in all the seven groups. Most of the proteins in the HMWP, HSP80, HSP70, LMWP and VLMWP groups were supressed throughout exposure and recovery. Augmentation of a few proteins occurred in HMWP, HSP60, and LMWP groups. Four proteins were newly elicited in HMWP, HSP60 and LMWP group. Available information shows that HSP70 family is a popular choice for biomarker research. Induction of these proteins is vital to the protection of stressed cells. But the present result showed that HSP70 is not a sensitive indicator of pesticide stress. The response of HSP60 family was more regular under pesticide stress. Considering the chaperone function of these proteins, it would be reasonable to presume that these proteins would serve as better biomarker than HSP70 in pesticide induced stress in fish.