Lee J S, Trowsdale J, Bodmer W F
Proc Natl Acad Sci U S A. 1982 Jan;79(2):545-9. doi: 10.1073/pnas.79.2.545.
Two cDNA clones, pDRH1 and pDRH2, containing sequences specific for human HLA-DR antigens were isolated from a bank of cDNA clones made from partially purified HLA-DR mRNA from the human lymphoblastoid cell line Maja. The clones were specific for the Mr 34,000 HLA-DR antigen glycoprotein chain. The identity of these clones was established by (i) their ability to hybridize specifically to HLA-DR mRNA in a positive selection assay; (ii) mRNA species hybridizing to the cDNA clones were expressed in B-cell but not in T-cell or fibroblast cell cultures; and (iii) a nucleotide sequence in the longer clone, pDRH2, could be translated into an amino acid sequence that is identical to the limited NH2-terminal amino acid sequence available for the purified HLA-DR antigen Mr 34,000 chain. Analysis of DNA from human, mouse, and human--mouse somatic cell hybrid lines by Southern transfer of restriction endonuclease digests indicated that the HLA-DR heavy chain is encoded in chromosome 6. This finding is compatible with the location of at least one of the HLA-D/DR heavy chain genes within the HLA region. In addition, the sequences coding for HLA-DR heavy chain appear to be present in only one or a few copies in the genome and to be relatively simple in structure.
从由人淋巴母细胞系玛雅（Maja）部分纯化的HLA - DR mRNA构建的cDNA克隆库中，分离出两个含有人类HLA - DR抗原特异性序列的cDNA克隆，即pDRH1和pDRH2。这些克隆对分子量为34,000的HLA - DR抗原糖蛋白链具有特异性。通过以下方式确定了这些克隆的身份：（i）在阳性选择试验中它们与HLA - DR mRNA特异性杂交的能力；（ii）与cDNA克隆杂交的mRNA种类在B细胞培养物中表达，但在T细胞或成纤维细胞培养物中不表达；（iii）较长的克隆pDRH2中的核苷酸序列可以翻译成与纯化的分子量为34,000的HLA - DR抗原链的有限NH2末端氨基酸序列相同的氨基酸序列。通过限制性内切酶消化产物的Southern印迹分析人、小鼠和人 - 小鼠体细胞杂种系的DNA表明，HLA - DR重链由第6号染色体编码。这一发现与HLA - D/DR重链基因中至少一个位于HLA区域内的位置相符。此外，编码HLA - DR重链的序列在基因组中似乎仅以一个或几个拷贝存在，并且结构相对简单。
