Takeuchi H, Figueroa F, O'hUigin C, Klein J
Max-Planck-Institut für Biologie, Abteilung Immungenetik, Tübingen, Germany.
Immunogenetics. 1995;42(2):77-84. doi: 10.1007/BF00178581.
The zebrafish (Brachydanio rerio) offers many advantages for immunological and immunogenetic research and has the potential for becoming one of the most important nonmammalian vertebrate research models. With this in mind, we initiated a systematic study of the zebrafish major histocompatibility complex (Mhc) genes. In this report, we describe the cloning and characteristics of the zebrafish class I A genes coding for the alpha chains of the alpha beta heterodimer and thus complete the identification of all four classes and subclasses of the Mhc in this species. We describe the full class I alpha cDNA sequence as well as the exon-intron organization of the class I A genes, including intron sequences. We identify three families of class I A genes which we designate Brre-UAA, -UBA, and -UCA. The three families originated about the time of the divergence of cyprinid and salmonid fishes. All three families are members of an ancient lineage that diverged from another, older lineage also represented in cyprinid fishes before the radiation of teleost orders. The fish class I A genes therefore evolve differently from mammalian class I A genes, in which the establishment of lineages and families mostly postdates the divergence of orders.
斑马鱼（Brachydanio rerio）在免疫学和免疫遗传学研究方面具有诸多优势，有潜力成为最重要的非哺乳类脊椎动物研究模型之一。基于此，我们启动了对斑马鱼主要组织相容性复合体（Mhc）基因的系统研究。在本报告中，我们描述了编码αβ异二聚体α链的斑马鱼I类A基因的克隆及特征，从而完成了该物种Mhc所有四个类别和亚类的鉴定。我们描述了完整的I类α cDNA序列以及I类A基因的外显子 - 内含子结构，包括内含子序列。我们鉴定出三个I类A基因家族，分别命名为Brre - UAA、 - UBA和 - UCA。这三个家族大约起源于鲤科鱼类和鲑科鱼类分化之时。所有这三个家族都是一个古老谱系的成员，该谱系在硬骨鱼目辐射之前就已从另一个在鲤科鱼类中也存在的更古老谱系分化出来。因此，鱼类I类A基因的进化方式与哺乳类I类A基因不同，在哺乳类中，谱系和家族的形成大多发生在目分化之后。
