Gene cloning and sequence analysis of swine (crossbreeding pig) interleukin-6

The peripheral blood monocytes of swine(Crossbreeding Pig)were isolated and cultured in vitro Whereafter we extracted the total RNA from the cells and amplified the gene of interleukin6 with reverse transcription polymerase chain reaction(RTPCR)after the cells were incubated with the proper inducer(LPS or ConA)for 48 hours.The RTPCR product was cloned nto the pMD18T vector,and the extracted plasmid was sequenced after then.The result indicated that a recombinant plasmid(denoted as pMDpIL6)including the interleukin6 gene was obtained,Sequence analysis indicated that the cDNA of the interleukin6 gene was 716bp in length,where the open reading frame(ORF)was 636bp in length encoding 211 amino acids which was 24KD in molecular weight,and the isoelectric point of the interleukin6 protein was 5.5.The sequence of recombinant interleukin6 was compared with those from the swine of different origins in Genbank,and it only differed in one amino acid.Then,the recombinant interleukin6 was aligned with those from the different species in Genbank,and the homology of the sequence of amino acid residues ranged from 78.1% to 90.1%.Meanwhile,our result suggested that the interleukin[CD*2]6 gene was of species diversity,and that different animals were closer on the phylogenetic tree while their interleukin6 genes were closer in sequence distances.