Bao Yonghua, Wu Sun, Zang Yunlong, Wang Hui, Song Xiangfeng, Xu Chunyang, Xie Bohong, Guo Yongchen
Department of Basic Immunology, Xinxiang Medical University, Jinsui Street, Xinxiang 453003, PR China.
Vet Immunol Immunopathol. 2012 Jun 15;147(1-2):44-50. doi: 10.1016/j.vetimm.2012.04.018. Epub 2012 Apr 20.
To date, most jawed vertebrate species encode more than one immunoglobulin light (IgL) chain isotypes. It has been shown that several bird species (chickens, white Pekin or domestic duck, and zebra finches) exclusively express lambda isotype. We analyze here the genomic organization of another bird species turkey IgL genes based on the recently released genome data. The turkey IgL locus located on chromosome 17 spans approximately 75.2kb and contains a single functional V(λ) gene, twenty V(λ) pseudogenes, and a single functional J(λ)-C(λ) block. These data suggest that the genomic organization of bird IgL chain genes seems to be conserved. Ten cDNA clones from turkey Igλ chain containing almost full-length V(λ), J(λ) and C(λ) segments were acquired. The comparison of V(λ) cDNA sequences to all the germline V(λ) segments suggests that turkey species may be generating IgL chain diversity by gene conversion and somatic hypermutation like the chicken. This study provides insights into the immunoglobulin light chain genes in another bird species.
迄今为止，大多数有颌脊椎动物物种编码不止一种免疫球蛋白轻链（IgL）同种型。已表明几种鸟类（鸡、白来航鸡或家鸭以及斑胸草雀）仅表达λ同种型。我们在此基于最近发布的基因组数据，分析另一种鸟类火鸡IgL基因的基因组组织。位于17号染色体上的火鸡IgL基因座跨度约为75.2kb，包含一个功能性V(λ)基因、二十个V(λ)假基因以及一个功能性J(λ)-C(λ)模块。这些数据表明鸟类IgL链基因的基因组组织似乎是保守的。获得了十个来自火鸡Igλ链的几乎包含全长V(λ)、J(λ)和C(λ)片段的cDNA克隆。将V(λ)cDNA序列与所有种系V(λ)片段进行比较表明，火鸡物种可能像鸡一样通过基因转换和体细胞超突变产生IgL链多样性。这项研究为另一种鸟类的免疫球蛋白轻链基因提供了见解。
