中文摘要：

为了深入了解绵羊主要组织相容性复合体（MHC）ClassⅡa区段基因组结构,利用已构建的中国美利奴细毛羊细菌人工染色体（BAC）文库和MHC区段高密度物理图谱研究ClassⅡa的基因组成。ClassⅡa亚区包括BAC克隆225J15、283N15和271H22,基因组大小为333 962bp。对ClassⅡa已知的基因座DRB1、DRA、DQB1、DQB2、DQA1和DQA2设计特异性引物,克隆出这6个基因的全长序列。将这6个基因定位在ClassⅡa基因组上,6个基因的基因组长度分别为10.8、3.5、8.7、9.4、3.5和5.7kb。选取编码MHC-Ⅱ类分子α链的DQA1和编码MHC-Ⅱ类分子β链的DRB1进行原核表达,SDS-PAGE检测蛋白质大小分别为28ku和30ku。

英文摘要：

For a deeper understanding of the genomic organization of sheep major histocompatibility complex class Ⅱa region,a bacterial artificial chromosome（BAC） library of Chinese Merino fine-wool sheep and high-density physical map constructed by our laboratory were used to study the Ⅱa organization.Class Ⅱa region includes the BAC clone 225J15,283N15 and 271H22,and the contig size is 333 962 bp.Specific primers for the Class Ⅱa known loci DRB1,DRA,DQB1,DQB2,DQA1 and DQA2 were designed to clone the 6 full length genes.The 6 genes were located in the Class Ⅱa region,and the genomic sequence lengths of these genes were 10.8 kb,3.5 kb,8.7 kb,9.4 kb,3.5 kb and 5.7 kb respectively.The DQA1 encoding MHC-Ⅱ molecular α chain and DRB1 encoding MHC-Ⅱ molecular β chain were proceed to the prokaryotic expression.The protein size was detected by SDS-PAGE and the molecular weights of them were 28 ku and 30 ku respectively.Then it can lay the foundation for the corresponding study of gene function.