Origin and Evolution of the Self-Nonself Discrimination System : Role of Genome Duplication in the Emergence of the Adaptive Immune System

脊椎动物的自我-非自我辨别系统是在进化过程中建立起来的。因此，要了解该系统的生物学意义，仅研究人类和小鼠是不够的。因此，这个项目的目的是研究mammals.to到各种动物的自我-非自我辨别系统的结构和功能。首席研究员发现，人类和小鼠等哺乳动物的基因组包含与主要组织相容性复合体（MHC）同源的区域。这些区域和MHC区域似乎已经分歧作为基因组复制的结果，发生在脊椎动物进化的早期，最有可能在一个共同的祖先有颚脊椎动物。Flajnik博士继续他对非洲爪蟾MHC基因组组织的研究。他还研究了鲨鱼Ig样NAR基因多样化的分子机制。Du Pasquier博士发现了大量属于CTX基因家族的人类基因。考夫曼博士测定了鸡MHC的完整核苷酸序列，发现与哺乳动物的情况不同，鸡MHC不含LMP基因，但含有C型凝集素样NK受体基因。

The self-nonself discrimination system of vertebrates was built over evolutionary time. Therefore, to understand the biological significance of the system, it is insufficient to study only humans and mice. The aim of this project was, therefore, to study the structure and function of the self-nonself discrimination system in a wide variety of animals ranging from mammals.to fish. The head investigator discovered that the genome of mammals such as humans and mice contains the regions paralogous to the major histocompatibility complex (MHC). These regions and the MHC region appear to have diverged as a result of genome duplication that took place early in vertebrate evolution, most likely in a common ancestor of jawed vertebrates. Dr. Flajnik continued his work on the genomic organization of the Xenopus MHC. He also studied the molecular mechanisms by which the shark Ig-like NAR gene diversifies. Dr. Du Pasquier identified a large number of human genes belonging to the CTX gene family. Dr. Kaufman determined the complete nucleotide sequence of the chicken MHC and found that, unlike the situation in mammals, the chicken MHC does not contain the LMP genes, but that it contains C-type lectin-like NK receptor genes.