Zebrafish HSC70 promoter to express carp muscle-specific creatine kinase for acclimation under cold condition

Zebrafish (Danio rerio) is used as a model system for in vivo studies. To expand the research scope of physical, biochemical and physiological studies, a cold-tolerant model of zebrafish was developed. The common carp (Cyprinus carpio) muscle form of creatine kinase (CK, EC 2.7.3.2) can maintain enzymatic activity at a temperature of around 15A degrees C. However, a cold-inducible promoter of zebrafish, hsc 70 (heat shock protein 70 cognate), is able to increase the expression of gene product by 9.8 fold at a temperature of 16A degrees C. Therefore, the carp CK gene was promoted by hsc 70 and transfected into zebrafish embryos. Resulting transgenic zebrafish survived and could maintain its swimming behavior at 13A degrees C, which was not possible with the wild-type zebrafish. The swimming distance of the transgenic fish was 42% greater than that of the wild type at 13A degrees C. This new transgenic fish model is ideal for studies of ectothermal vertebrates in low-temperature environments.