Hosokawa T, Tanioka Y, Tanigawa M, Matsumoto Y, Onodera T, Matsumoto Y
Department of Molecular Immunology, School of Agriculture and Life Sciences, University of Tokyo, Japan.
J Vet Med Sci. 1998 Jun;60(6):725-9. doi: 10.1292/jvms.60.725.
Major histocompatibility complex (MHC) of pigs is known as swine leukocyte antigen (SLA). The cDNA encoding a new allele of SLA class II DQ beta-chain was successfully isolated from a CSK miniature pig (derived from Göttingen strain) and characterized by sequence analyses. SLA-DQB cDNA fragment encoding beta 2-domain was amplified by reverse transcriptase-polymerase chain reaction using the sequences preserved in a various vertebrates as primers. Using non-radioisotope technique with the PCR product as a probe, cDNA clone G01 was isolated from a spleen cDNA library, and nucleotide sequence of this clone was determined. This clone encompassed a whole SLA-DQ beta-chain coding region, containing a total length of 1161 nucleotides with an open reading frame (ORF) of 786 nucleotides, 5' untranslated region of 15 nucleotides, and 3' untranslated region of 360 nucleotides ending with a canonical polyadenylation signal, followed by a poly A tail. Sequence comparisons of the ORF of this clone with those of known SLA-DQB genes confirmed that this clone is a new allele (SLA-DQB*G01). Phylogenetic analysis of the nucleotide sequences of swine, human, and murine MHC class II genes indicated that SLA-DQB was more similar to HLA-DQB1 than H-2A beta. Comparison of the nucleotide and deduced amino acid sequences among SLA-DQB alleles showed that the SLA-DQ beta-chain polymorphism was found almost in beta 1-domain which contains the antigenic peptide binding sites.
猪的主要组织相容性复合体（MHC）被称为猪白细胞抗原（SLA）。从一只CSK小型猪（源自哥廷根品系）中成功分离出编码SLA II类DQβ链新等位基因的cDNA，并通过序列分析对其进行了表征。以各种脊椎动物中保存的序列为引物，通过逆转录聚合酶链反应扩增编码β2结构域的SLA - DQB cDNA片段。使用非放射性同位素技术，以PCR产物为探针，从脾脏cDNA文库中分离出cDNA克隆G01，并测定了该克隆的核苷酸序列。该克隆包含整个SLA - DQβ链编码区，全长1161个核苷酸，开放阅读框（ORF）为786个核苷酸，5'非翻译区为15个核苷酸，3'非翻译区为360个核苷酸，末端带有典型的多聚腺苷酸化信号，随后是一个多聚A尾巴。将该克隆的ORF与已知SLA - DQB基因的ORF进行序列比较，证实该克隆是一个新等位基因（SLA - DQB*G01）。对猪、人和小鼠MHC II类基因的核苷酸序列进行系统发育分析表明，SLA - DQB与HLA - DQB1的相似性高于H - 2Aβ。比较SLA - DQB等位基因之间的核苷酸和推导的氨基酸序列表明，SLA - DQβ链多态性几乎存在于包含抗原肽结合位点的β1结构域中。
