Cloning and sequencing of chicken interleukin-2 gene

The chicken interleukin-2 gene, a cDNA fragment about 450bp in length, was amplified from ConA-stimulated chicken spleen cells by RT-PCR using a pair of primers which were designed and synthesized according to the ChIL-2 gene sequence in GenBank published by Sundick. The gene was inser- ted into pBluescriptⅡKS(+) and identified by endonuclease and DNA sequencing. The result of sequence analysisshowed that the gene encoding a protein of 142 amino acids residues. An amino acid absence was found at the region of 49 compared with all other published chicken IL-2 genes. The cloned gene was the only chicken IL-2 gene that an amino acid is absent at the region. The other amino acids were consistent with that of Broiler, SC and Xiaoshan chickens and there are close relationships among them, but there is 1-4 amino acids difference between the deduced amino acids sequence from the cloned gene and that from Kestrel Leghorn, Leghorn SPF, Obese, Silky, Chenren and Xianju chickens.