Prokaryotic expression of chicken interferon- fusion protein and its effect on expression of poultry heat shock protein 70 under heat stress

摘要

Interferons have attracted considerable attention due to their vital roles in the host immune response and low induction of antibiotic resistance. In this study, total RNA was extracted from spleen cells of chicken embryos inoculated with Newcastle disease vaccine, and the full-length chicken interferon- (ChIFN-) gene was amplified by RT-PCR. The full complementary DNA sequence of the ChIFN- gene was 495bp long and was cloned into the prokaryotic expression vector pProEXHT(b). The plasmid was transformed into Escherichia coli DH5 and the expression of ChIFN- was induced by isopropyl -D-1-thiogalactopyranoside. Sodium dodecyl sulfate - polyacrylamide gel electrophoresis and Western blot results showed the expressed fusion protein had a molecular weight of approximately 18kDa and was recognized by an anti-His mAb. Moreover, ChIFN- was found to demonstrate anti-viral activity in vitro. To test the in vivo function of ChIFN- in broilers under heat stress, a total of 100 broilers were randomly assigned to either a control group or a treated group, in which they were hypodermically injected with recombinant ChIFN-. Results demonstrated ChIFN- affects the messenger RNA expression levels of heat shock protein 70 (HSP70) in the heart and lung tissues, and decreases the concentration of HSP70 in serum. Therefore, we conclude recombinant ChIFN- can reduce heat stress to some extent in vivo.