Differential expression of the heat shock protein Hsp70 in natural populations of the tilapia, Sarotherodon melanotheron, acclimatised to a range of environmental salinities

Abstract

These results indicate that, although S. melanotheron can colonise extremely saline environments, the overexpression of Hsp70 combined with the higher Naka mRNA expression reveals that this represents a chronic stress. The induction of Hsp70 was, therefore, a biomarker of chronic hyper-osmotic stress which presumably can be linked to the impaired growth performance and precocious reproduction that have been demonstrated in the populations at the extremely saline sites.