College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, China.
College of Grassland Agriculture, Northwest A&F University, Yangling, 712100, China.
Dev Comp Immunol. 2024 Nov;160:105234. doi: 10.1016/j.dci.2024.105234. Epub 2024 Jul 26.
Mink are susceptible to viruses such as SARS-CoV-2, H1N1 and H9N2, so they are considered a potential animal model for studying human viral infections. Therefore, it is important to study the immune system of mink. Immunoglobulin (Ig) is an important component of humoral immunity and plays an important role in the body's immune defense. In this study, we described the gene loci structure of mink Ig germline by genome comparison, and analysed the mechanism of expression diversity of mink antibody library by 5'RACE and next-generation sequencing (NGS). The results were as follows: the IgH, Igκ and Igλ loci of mink were located on chromosome 13, chromosome 8 and chromosome 3, respectively, and they had 25, 36 and 7 V genes, 3, 5 and 7 J genes and 10 DH genes, respectively. Mink Ig heavy chain preferred the IGHV1, IGHD2 and IGHJ4 subgroups, κ chain mainly use the IGKV1, IGKJ1 and IGHL4 subgroups, and λ chain mainly use the IGLV3 and IGLJ3 subgroups. Linkage diversity analysis revealed that N nucleotide insertion was the main factor affecting the linkage diversity of mink Igs. On the mutation types of mink Ig Somatic Hypermutation (SHM), the high mutation types of heavy chain were mainly G > A, C > T, T > C, A > G, C > A, G > T, A > C, and T > G; the high mutation types of κ chain were G > A and T > C; and the high mutation types of λ chain were G > A and A > G. The objective of this study was to analyse the loci structure and expression diversity of Ig in mink. The results contribute to our comprehension of Ig expression patterns in mink and were valuable for advancing knowledge in mink immunogenetics, exploring the evolution of adaptive immune systems across different species, and conducting comparative genomics research.
水貂易感染 SARS-CoV-2、H1N1 和 H9N2 等病毒，因此被认为是研究人类病毒感染的潜在动物模型。因此，研究水貂的免疫系统非常重要。免疫球蛋白（Ig）是体液免疫的重要组成部分，在机体免疫防御中发挥着重要作用。本研究通过基因组比较描述了水貂 Ig 胚系基因座结构，并通过 5'RACE 和下一代测序（NGS）分析了水貂抗体库表达多样性的机制。结果如下：水貂的 IgH、Igκ 和 Igλ 基因座分别位于第 13 号、第 8 号和第 3 号染色体上，分别具有 25、36 和 7 个 V 基因、3、5 和 7 个 J 基因和 10 个 DH 基因。水貂 Ig 重链主要偏好 IGHV1、IGHD2 和 IGHJ4 亚群，κ 链主要使用 IGKV1、IGKJ1 和 IGHL4 亚群，λ 链主要使用 IGLV3 和 IGLJ3 亚群。连锁多样性分析表明，N 核苷酸插入是影响水貂 Ig 连锁多样性的主要因素。在水貂 Ig 体细胞高频突变（SHM）的突变类型上，重链的高突变类型主要为 G>A、C>T、T>C、A>G、C>A、G>T、A>C 和 T>G；κ 链的高突变类型为 G>A 和 T>C；λ 链的高突变类型为 G>A 和 A>G。本研究旨在分析水貂 Ig 的基因座结构和表达多样性。研究结果有助于我们了解水貂 Ig 的表达模式，为水貂免疫遗传学的研究提供了有价值的参考，同时也有助于探索不同物种适应性免疫系统的进化以及比较基因组学的研究。
