Tissue- and stressor-specific differential expression of two hsc70 genes in carp.

Two genes expressing 70 kDa heat shock proteins were identified in Cyprinus carpio. The sequence similarities and the intron-interrupted structure of the coding regions indicate that carp Hsc70-1 and Hsc70-2 belong to the Hsp70 cognate subfamily. The expressions of the two hsc70 genes were followed by semi-quantitative RT-PCR. Both genes are expressed under unstressed conditions in a characteristic tissue-specific manner. Inducibility of the response to elevated temperature, cold shock, and Cd treatment was investigated in the liver and muscle, in whole-animal experiments. Both genes were insensitive to or only weakly induced by the stressors, with two exceptions: Cd treatment resulted in an 11-13-fold enhanced induction of hsc70-1 in the liver and cold shock enhanced induction of hsc70-2 in the muscle by 7.5-10-fold.