Gene organization of DC and DX subregions of the human major histocompatibility complex.
Gene organization of DC and DX subregions of the human major histocompatibility complex.
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人类主要组织相容性复合体的 DC 和 DX 亚区的基因组织。
DOI：
10.1073/pnas.82.10.3410
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发表时间：
1985
影响因子：
11.1
通讯作者：
Strominger,JL
中科院分区：
文献类型：
--
作者：
Okada,K;Boss,JM;Prentice,H;Spies,T;Mengler,R;Auffray,C;Lillie,J;Grossberger,D;Strominger,JL
人类主要组织相容性复合体 (MHC) 的 DC 和 DX 亚区已从人类 B 细胞系 Priess 制成的粘粒文库中克隆出来。 DC 亚区长 48 KB，包括 DC α 和 DC β 基因。第二个类似 DC 的区域是 DX 亚区域，长 35 kb，包含 DX α 基因和新发现的称为 DX beta 的 β 基因。由于DC和DX基因在核苷酸序列、基因大小、外显子-内含子组织和转录方向方面高度同源，因此DC和DX亚区可能是通过祖先α-β基因对的复制产生的。核苷酸测序表明所有四个基因都具有完整的编码序列和启动子区域。这四个基因和七个其他II类基因的上游启动子序列在核苷酸-69至-78和-98至-110处的同源性突出了这些先前描述的保守元件。此外，还观察到侧翼α基因特异性和β基因特异性序列的显着保守性。 Priess DNA 与 DC α 和 DC β cDNA 探针以及分离的粘粒克隆的 Southern 印迹比较表明，（i）人类染色体仅编码两个 DC α 相关基因和两个 DC β 相关基因，即 DC α、DX α、DC β 和 DX β，以及（ii）DC 和 DX 亚区在 Priess 细胞中是纯合的。
The DC and DX subregions of the human major histocompatibility complex (MHC) have been cloned from a cosmid library made from a human B-cell line, Priess. The DC subregion, 48 kilobases, includes the DC alpha and DC beta genes. A second DC-like region, the DX subregion, 35 kilobases, contains the DX alpha gene and a newly found beta gene termed DX beta. Since the DC and DX genes are highly homologous in nucleotide sequence, gene size, exon-intron organization, and direction of transcription, the DC and DX subregions were presumably generated by duplication of an ancestral alpha-beta gene pair. Nucleotide sequencing indicates that all four genes have intact coding sequences and promoter regions. Homology between the upstream promoter sequences of these four genes and seven other class II genes at nucleotides -69 to -78 and -98 to -110 highlights these previously described conserved elements. Moreover, a striking conservation of flanking alpha-gene-specific and beta-gene-specific sequences has been observed. Comparison of Southern blots of Priess DNA with DC alpha and DC beta cDNA probes with isolated cosmid clones showed that (i) the human chromosome encodes only two DC alpha-related and two DC beta-related genes, namely, DC alpha, DX alpha, DC beta, and DX beta, and (ii) the DC and DX subregions are homozygous in Priess cells.