Evolutionary aspects of immunoglobulin heavy chain variable region (VH) gene subgroups.
Evolutionary aspects of immunoglobulin heavy chain variable region (VH) gene subgroups.
复制标题
免疫球蛋白重链可变区 (VH) 基因亚群的进化方面。
DOI：
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发表时间：
1983
影响因子：
11.1
通讯作者：
D. Givol
中科院分区：
文献类型：
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作者：
G. Rechavi;D. Ram;L. Glazer;R. Zakut;D. Givol
我们分离并测定了两个人生殖系重链可变区（VH）基因的序列，并将它们与小鼠VH基因进行了比较。结果表明，人VHI亚群与小鼠VHII亚群在进化上相关。同一亚组的VH基因中的同源性的进化保留不仅包括编码区，而且包括内含子大小和非编码区中的同源性。这表明VH基因亚组构成了一个经历协同进化的多基因家族。不同物种中同一亚群基因间的同源性大于同一物种中不同亚群基因间的同源性。VHII基因之一在互补决定区2（CDR 2）中含有先前显示在VHIII基因的CDR 2中和在重链多样性区基因中的13个碱基对DH [Wu，T. T. & Kabat，E. A.等人（1982）Proc. Acad. Sci. USA 79，5031-5032]，表明多样性区基因序列插入VH基因中。其中一个人VH基因是假基因，因为终止子，这与我们以前的结果一起，表明VH基因库包含40%的假基因。在一个VH基因中，在基因的5'和3'末端的正向和反向重复序列表明了一个潜在的转座因子，其包含整个VH基因。这是可能的，这样的结构可以促进突变复制和VH基因家族的快速扩展。
We isolated and determined the sequences of two human germ-line heavy chain variable region (VH) genes and compared them with mouse VH genes. The results show that the human VHI subgroup is evolutionarily related to the mouse VHII subgroup. Evolutionary preservation of homologies in VH genes of the same subgroup includes not only the coding region but also intron size and homology in noncoding regions. This suggests that a VH gene subgroup constitutes a multigene family that undergoes concerted evolution. The homology between genes of the same subgroup in different species is greater than that between genes of different subgroups within a species. One of the VHII genes contains, in complementarity-determining region 2 (CDR2), a 13-base-pair previously shown to be in CDR2 of a VHIII gene and in a heavy chain diversity region gene, DH [Wu, T. T. & Kabat, E. A. (1982) Proc. Natl. Acad. Sci. USA 79, 5031-5032], suggesting the insertion of diversity region gene sequences into the VH gene. One of the human VH genes is a pseudogene because of a terminator, which, together with our previous results, shows that the VH gene repertoire contains 40% pseudogenes. In one of the VH genes, direct and inverted repeats at both 5' and 3' ends of the gene suggest a potential transposable element that encompasses the entire VH gene. It is possible that such a structure may facilitate saltatory replication and rapid expansion of VH gene families.