Abstract Based on analysis of available genome sequences, five gene lineages of MHC class I molecules (MHC I-U, -Z, -S, -L and -P) and one gene lineage of MHC class II molecules (MHC II-D) have been identified in Osteichthyes. In the latter lineage, three MHC II molecule sublineages have been identified (MHC II-A, -B and -E). As regards MHC class I molecules in Osteichthyes, it is important to take note of the fact that the lineages U and Z in MHC I genes have been identified in almost all fish species examined so far. Phylogenetic studies into MHC II molecule genes of sublineages A and B suggest that they may be descended from the genes of the sublineage named A/B that have been identified in spotted gar (Lepisosteus oculatus). The sublineage E genes of MHC II molecules, which represent the group of non-polymorphic genes with poor expression in the tissues connected with the immune system, are present in primitive fish, i.e. in paddlefish, sturgeons and spotted gar (Lepisosteus oculatus), as well as in cyprinids (Cyprinidae), Atlantic salmon (Salmo salar), and rainbow trout (Oncorhynchus mykiss). Full elucidation of the details relating to the organisation and functioning of the particular components of the major histocompatibility complex in Osteichthyes can advance the understanding of the evolution of the MHC molecule genes and the immune mechanism.

中文翻译：

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骨鱼的主要组织相容性复合体

摘要 基于对现有基因组序列的分析，MHC I 类分子的 5 个基因谱系（MHC IU、-Z、-S、-L 和 -P）和 MHC II 类分子的一个基因谱系（MHC II-D）已被发现。在 Osteichthyes 中鉴定。在后一个谱系中，已经确定了三个 MHC II 分子亚谱系（MHC II-A、-B 和 -E）。关于 Osteichthyes 中的 MHC I 类分子，重要的是要注意这样一个事实，即 MHC I 基因中的谱系 U 和 Z 已在迄今为止检查的几乎所有鱼类物种中得到鉴定。对亚系 A 和 B 的 MHC II 分子基因的系统发育研究表明，它们可能是在斑点雀鹛（Lepisosteus oculatus）中鉴定的名为 A/B 的亚系基因的后裔。MHC II分子的亚系E基因，代表在与免疫系统相关的组织中表达较差的一组非多态性基因，存在于原始鱼类中，即白鲟、鲟鱼和斑点雀鲷（Lepisosteus oculatus），以及鲤科鱼类（Cyprinidae）、大西洋鲑鱼 (Salmo salar) 和虹鳟鱼 (Oncorhynchus mykiss)。全面阐明与骨鱼主要组织相容性复合体的特定成分的组织和功能有关的细节，可以促进对 MHC 分子基因进化和免疫机制的理解。