[Objective] This study aimed to obtain IL-10 (interleukin 10) full-length cDNA of common carp (Cyprinus carpio L.) and conduct the sequence analysis. [Method] The differentially expressed cDNA fragment was obtained by DD-RTPCR (differential display RT-PCR). The cDNA library of peripheral blood leukocytes which were separated from common carp and stimulated by mitogen was screened with a probe labeled with DIG (digoxigenin). The IL-10 full-length cDNA was cloned from 0.8×104 pfu of recombinant phages, and the sequence analysis and homology comparison were carried out. [Result] Sequence analysis indicated that the IL-10 full-length cDNA of common carp was 1 117 bp long, containing a 55 bp 5’-UTR, a 522 bp 3’-UTR, and a 540 bp open reading frame(ORF) encoding 179 amino acids. In addition, there were three mRNA instability motifs (ATTTA) in the 3’-untranslated region. The deduced protein sequence shared typical sequence features of the IL-10 family. Homology comparison indicated that the obtained sequence shared 89.1% homology with the carp IL-10 gene from GenBank. [Conclusion] This study laid foundation for further study of the expression manner, functional characteristic and regulation mechanism of IL-10 in vivo and the interaction mechanism in the inflammatory reaction and immune response.
[Objective] The research aimed to carry out the cloning, identification and sequence analysis of full-length cDNA of carp interferon γ-2β （IFNγ-2β）. [Method] The cDNA library of peripheral blood leucocytes which were separated from carp and stimulated with mitogen was screened by a probe labeled with DIG. The IFNγ- 2β EST sequence was picked out from the constructed cDNA library of peripheral blood leucocyte, and the full length of carp interferon γ-2β was cloned. In addition, the sequence analysis was carried out. [Result] Three positive clones were obtained. Sequence analysis indicated that the sequence had a 119 bp 5’-UTR and a 218 bp 3’-UTR, and the open reading frame （ORF）of this gene was 537 bp which putatively coded 178 amino acids and there were several instable motifs for mRNA （ATTTA） in the 3’-untranslated region. Its homology with IFN from GenBank was up to 97% . Analysis on protein sequence and structure showed that the predicted protein sequence was identified as an IFN family signature. [Conclusion] The research laid the foundation for further studying the expression manner, function characteristic and regulation mechanism of IFNγ-2β in vivo and the action mechanism in the inflammatory reaction, emergency reaction and immune response.
