【作者】 董传举； 张江凡； 李胜杰； 吕红皂； 徐鹏； 李学军；

【Author】 DONG Chuanju;ZHANG Jiangfan;LI Shengjie;LV Hongzao;XU Peng;LI Xuejun;College of Fisheries, Henan Normal University;

【机构】 河南师范大学水产学院； 中国水产科学研究院珠江水产研究所； 厦门大学海洋与地球学院；

【摘要】 IL17 receptor(IL17R)基因家族在哺乳动物中包含五个成员,均为I型单次跨膜蛋白。作为IL17基因的受体,IL17R在宿主防御和免疫损伤等方面均有重要作用。鲤鱼和草鱼作为鲤科鱼类最具代表性的两种鱼类,不仅是全球范围内的重要养殖品种,也大量应用于基因起源进化的研究。本研究中,通过对鲤鱼和草鱼基因组数据的序列比对和分析,分别识别了9个和5个IL17R基因家族成员,并进行基因注释和命名。系统进化分析结果表明,该基因家族具有一定的保守性,且不存在硬骨鱼特有的基因。比较基因组分析结果显示,与四足动物相比,大多数硬骨鱼类IL17R基因没有明显增多。而鲤鱼与草鱼等硬骨鱼类相比,除IL17RB外,所有IL17R基因家族成员均加倍。鲤鱼和草鱼健康组织的表达谱分析结果同样表明,鲤鱼IL17R基因的不同拷贝之间已经发生了快速进化及亚功能化,并且这种现象在鲤鱼四倍体基因组中普遍存在。鲤鱼与其他脊索动物IL17R基因家族的比较分析,有助于基因起源分化及全基因组复制后功能分化的研究,也为重要免疫相关基因的发掘和基因组演化机制等理论研究奠定一定基础。更多还原

【Abstract】 To date, five members of the IL17 receptor(IL17R) family, IL17 RE have been reported in mammals. All of them are single transmembrane proteins. As one of the important mediators of immune responses, IL17 R expression has been linked with the protection of immunity, excessive tissue inflammation and immune damage. As the representative species of Cyprinidae, common carp(Cyprinus carpio) and grass carp(Ctenopharyngodon idellus) are two widespread freshwater fish which have cultural histories. These two specises have become the vital significance materials to study the origin and evolution of genes in terms of organic evolutionary history. We identified and characterized nine IL17 R and five IL17 R homologues from their genomic databases respectively. Along with gene annotation and nomenclature, phylogenetic analysis based on amino acid sequences of the IL17 R proteins in 12 species showed highly conservative and no specific genes in teleosts. However, comparative genomics analysis of these species revealed that no extensive IL17 R gene copies in the teleost lineage compared with tetrapods. Nevertheless, except for IL17 RB genes, all of the members showed extensive gene duplications. Expression profiling showed that most of the IL17 R genes are expressed with tissue-specific. We postulated that the expansion of the IL17 R genes in common carp allowed the acquisition of novel functions and subfunctionalization during evolution. Our study had provided insights into gene duplication, divergence post multiple rounds of whole genome duplication.更多还原