Lefranc M P, Forster A, Rabbitts T H
Nature. 1986;319(6052):420-2. doi: 10.1038/319420a0.
Selective cloning procedures for T-cell-specific complementary DNAs have revealed the existence of a gene designated gamma as well as the main antigen receptor alpha- and beta-chain genes. The gamma-chain genes undergo rearrangement during T-cell differentiation but the patterns and complexity of such rearrangements differ markedly in mouse and human. In mouse, a panel of cytotoxic T-lymphocyte clones exhibit the same rearrangement pattern with a gamma-chain gene probe and a set of three gamma-chain variable (V) genes have been identified in the DNA. Clonal diversity in mouse seems to be confined to V-J (joining) regions. In contrast, human T-cell lines exhibit diverse rearrangements suggestive of a family of differing V gamma genes variously rearranging to the two gamma-chain constant (C) region genes. Here we report the cloning of two very different V gamma genes rearranged to J segments upstream of the two human C gamma genes. Both V gamma genes are rearranged productively but nucleotide sequence comparison shows that they possess very little homology with each other. This shows that human T-cell V gamma genes exist which differ significantly from each other at the nucleotide level and that such diverse genes can be usefully rearranged in different T cells.
针对T细胞特异性互补DNA的选择性克隆程序揭示了一个名为γ的基因以及主要抗原受体α链和β链基因的存在。γ链基因在T细胞分化过程中会发生重排，但这种重排在小鼠和人类中，其模式和复杂性存在显著差异。在小鼠中，一组细胞毒性T淋巴细胞克隆用γ链基因探针显示出相同的重排模式，并且在DNA中已鉴定出一组三个γ链可变（V）基因。小鼠中的克隆多样性似乎局限于V-J（连接）区域。相比之下，人类T细胞系表现出多样的重排，提示存在一系列不同的Vγ基因，它们以不同方式重排至两个γ链恒定（C）区域基因。在此，我们报告克隆了两个非常不同的Vγ基因，它们重排至两个人类Cγ基因上游的J片段。两个Vγ基因均发生了有效重排，但核苷酸序列比较表明它们彼此之间几乎没有同源性。这表明人类T细胞Vγ基因在核苷酸水平上彼此存在显著差异，并且这种多样的基因能够在不同的T细胞中有效地重排。
