【作者】 韩红兵； 徐署光； 连正兴； 陆泉枝； 李宁；

【Author】 HAN Hong-bing, XU Shu-guang, LIAN Zheng-xing, LU Quan-zhi, LI Ning(1.College of Animal Science and technology, China Agricultural University, Beijinl00094; 2. State Key Laboratory of Agrobiotechnology, Beijing 100094; 3. Laboratory of Animal Genetics and Breeding, Ministry of Agriculture, Beijing100094;China)

【机构】 中国农业大学动物科技学院农业部畜禽遗传育种重点实验室； 农业生物技术国家重点实验室农业部畜禽遗传育种重点实验室；

【摘要】 IL-12是调节体内产生免疫反应的一个重要细胞因子,是目前所有发现的细胞因子中对体内免疫活性细胞的诱导作用和调节作用最强、范围最广的一类。IL-12由35kDa（P40）和40kDa（P40）两个亚基通过二硫键相连组成异源二聚体糖蛋白。根据已发表的IL-12两个亚基P40cDNA序列（NM₀00882）与P40cDNA序列（NM₀02187）设计两对引物。以LPS刺激的人脐血淋巴细胞为材料,采用RT-PCR技术从总的RNA扩增人IL-12基因,包括完整的前体蛋白编码序列。所得到的序列与GeneBank中发表的一致,但与CLMF、NKSF序列有所差异。P40同CLMF相比,244aa密码子GAC（Asp）→GAT（Asp）、247aa密码子ACG（Thr）→ATG（Met）;与NKSF比较,44aa密码子GTC（Val）→GTG（Val）。P40同NKSF比较239aa密码子AAC（Asn）→AAG（Lys）,291aa密码子ACC（Thr）→ACG（Thr）;P40同CLMF相比较,氨基酸与核苷酸序列完全一致。通过与不同物种氨基酸及核苷酸序列比较分析,P40亚基与其他动物的同源性80%以上P40亚基与其他动物同源性在70%的水平。序列分析结果表明克隆的IL-12基因序列是正确的、可靠的。更多还原

【Abstract】 Based on the published human of IL-12 cDNA sequences in GenBank, two sets of primers were designed and synthesized. The total RNA was extracted from LPS-stimulated lymphocytes of cord blood of a Chinese newborn, then cDNAs of p40 (1100 bp) and p40 (870 bp) subunits of IL-12 were amplified by RT-PCR and cloned into pMDIS- T vector respectively. Compared our acquired sequence with the submitted sequences in the GenBank by using the BLAST, it was showed that the sequences were identical to that published in GenBank. But difference do exist when compared to the foreign sequences of CLMF, NKSF. Sequence analysis showed that the cloned sequence of p40 summit had a similarity over 80% and p40 subunit over 70% by sequence alignment of amino acids and nucleotides with other kinds of animals.更多还原