Chicken CD69 and CD94/NKG2-like genes in a chromosomal region syntenic to mammalian natural killer gene complex
Chicken CD69 and CD94/NKG2-like genes in a chromosomal region syntenic to mammalian natural killer gene complex
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DOI：
10.1007/s00251-007-0220-z
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发表时间：
2007-07-01
期刊：
影响因子：
3.2
通讯作者：
Zhu, James J.
中科院分区：
文献类型：
--
作者：
Chiang, Hsin-I;Zhou, Huaijun;Zhu, James J.
在哺乳动物中，自然杀伤（NK）细胞c型凝集素受体编码在一个称为自然杀伤基因复合物（NKC）的基因簇中。目前还没有在鸡肉中发现NKC。相反，在主要组织相容性复合体中发现了NK受体基因。本研究在1号染色体上与哺乳动物NKC区同源的区域发现了两个新的鸡c型凝集素样受体基因。染色体位置用荧光原位杂交验证。基于三维结构建模、序列同源性、染色体定位和进化分析，一个受体是哺乳动物分化簇69 （CD69）的同源物，另一个受体与CD94和NKG2高度同源。与在硬骨鱼类中发现的CD94/NKG2基因一样，鸡的CD94/NKG2基因同时具有人类CD94和NKG2A的特征。与哺乳动物NKC不同，这两种鸡c型凝集素受体并非紧密相连，根据鸡草图基因组序列，这两种受体之间有4200万个碱基对的距离。位于哺乳动物NKC外的其他几个基因的排列在鸡、人类和小鼠中是保守的。鸡NK c型凝集素样受体在NKC共合区表明该染色体区域在哺乳动物与鸟类分化之前就存在了。
In mammals, natural killer (NK) cell C-type lectin receptors were encoded in a gene cluster called natural killer gene complex (NKC). The NKC is not reported in chicken yet. Instead, NK receptor genes were found in the major histocompatibility complex. In this study, two novel chicken C-type lectin-like receptor genes were identified in a region on chromosome 1 that is syntenic to mammalian NKC region. The chromosomal locations were validated with fluorescent in situ hybridization. Based on 3D structure modeling, sequence homology, chromosomal location, and phlylogenetic analysis, one receptor is the orthologue of mammalian cluster of differentiation 69 (CD69), and the other is highly homologous to CD94 and NKG2. Like CD94/NKG2 gene found in teleostean fishes, chicken CD94/NKG2 has the features of both human CD94 and NKG2A. Unlike mammalian NKC, these two chicken C-type lectin receptors are not closely linked but separated by 42 million base pairs according to the chicken draft genome sequence. The arrangement of several other genes that are located outside the mammalian NKC is conserved among chicken, human, and mouse. The chicken NK C-type lectin-like receptors in the NKC syntenic region indicate that this chromosomal region existed before the divergence between mammals and aves.