Department of Pathology and Laboratory Medicine, Emory Vaccine Center, School of Medicine, Emory University, USA.
Curr Genomics. 2012 Apr;13(2):95-102. doi: 10.2174/138920212799860652.
Immunoglobulins (or antibodies) are an essential element of the jawed vertebrate adaptive immune response system. These molecules have evolved over the past 500 million years and generated highly specialized proteins that recognize an extraordinarily large number of diverse substances, collectively known as antigens. During vertebrate evolution the diversification of the immunoglobulin-encoding loci resulted in differences in the genomic organization, gene content, and ratio of functional genes and pseudogenes. The tinkering process in the immunoglobulin-encoding loci often gave rise to lineage-specific characteristics that were formed by selection to increase species adaptation and fitness. Immunoglobulin loci and their encoded antibodies have been shaped repeatedly by contrasting evolutionary forces, either to conserve the prototypic structure and mechanism of action or to generate alternative and diversified structures and modes of function. Moreover, evolution favored the development of multiple mechanisms of primary and secondary antibody diversification, which are used by different species to effectively generate an almost infinite collection of diverse antibody types. This review summarizes our current knowledge on the genomics and evolution of the immunoglobulin-encoding loci and their protein products in jawed vertebrates.
免疫球蛋白（或抗体）是有颌脊椎动物适应性免疫反应系统的一个重要组成部分。这些分子在过去的 5 亿年中不断进化，生成了高度专业化的蛋白质，能够识别数量异常庞大的各种不同物质，统称为抗原。在脊椎动物进化过程中，免疫球蛋白编码基因座的多样化导致了基因组组织、基因含量以及功能基因和假基因比例的差异。在免疫球蛋白编码基因座的“修补”过程中，经常会产生出由选择形成的、具有种系特异性的特征，以提高物种的适应性和适合度。免疫球蛋白基因座及其编码的抗体不断受到相反的进化力量的影响，这些力量或是为了保持原型结构和作用机制，或是为了产生替代的、多样化的结构和作用模式。此外，进化有利于发展多种主要和次要的抗体多样化机制，不同物种利用这些机制有效地产生了几乎无限多样的抗体类型。本综述总结了我们目前对有颌脊椎动物免疫球蛋白编码基因座及其蛋白质产物的基因组学和进化的了解。
