| 摘要: |
| 白细胞介素17受体（Interleukin 17 receptor ， IL-17R）家族与IL-17细胞因子家族介导的各类反应有着密切联系.IL-17RE-like （IL-17REL）是一类最新发现的IL-17受体，其结构与IL-17RE相似，但尚未发现其配体.本研究克隆得到大黄鱼（Larimichthys crocea）IL-17REL（LycIL-17REL）的全长cDNA，其开放阅读框全长1 659个核苷酸，推断可编码一个由552个氨基酸组成的蛋白，含有信号肽、胞外段、跨膜区和胞内段.与其他物种的IL-17REL相似，LycIL-17REL蛋白的胞外段具有一个保守的FN I-like结构域，而胞内段缺少IL-17受体家族保守的SEFIR （SEF and IL-17R）结构域.多序列比对分析表明LycIL-17REL与日本河豚（Takifugu rubripes）IL17REL的氨基酸序列同源性最高，序列一致性可达57-0%.系统进化分析表明，脊椎动物的IL-17受体家族可分为2类，IL-17RA/RB/RD为一类，IL-17RC/RE/REL为一类.其中鱼类及高等脊椎动物的IL-17REL与IL-17RE亲缘关系最近，并且推测二者可能是由同一基因从硬骨鱼类之前的物种中分化而来.组织分布表明LycIL-17REL在所有被检测的组织中为组成型表达，在黏膜相关组织如小肠和鳃中的表达量最高.大黄鱼受嗜水气单胞菌（Aeromonas hydrophila）诱导刺激后，LycIL-17REL在其头肾及鳃中的基因转录水平均显著上调.这表明LycIL-17REL可能在细菌感染引起的免疫反应中起着重要作用. |
| 关键词: 海洋生物学 大黄鱼；IL-17RE-like；分子及表达特征；进化 |
| DOI：10.3969/J.ISSN.2095-4972.2016.01.013 |
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| 基金项目:国家自然科学基金资助项目（31125027, 31001131）；厦门南方海洋研究中心资助项目（13GZP002NF08）；宁波大学水产浙江省重中之重一级学科开放基金资助项目（xkzsc07） |
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| Molecular characterization and evolutionary analysis of IL-17REL in Larimichthys crocea |
| DING Yang,AO Jing qun,AI Chun xiang,CHEN Xin hua |
| (College of Ocean and Earth Sciences， Xiamen University， Xiamen 361005， China;;Key Laboratory of Marine Biogenetic Resources， Third Institute of Oceanography， SOA， Xiamen 361005， China) |
| Abstract: |
| Interleukin 17 receptor （IL-17R） family play important roles in IL-17 cytokine family mediated immune responses. IL-17RE-like is a novel IL-17 receptor whose ligand has not been found yet to date. In this paper， we cloned an IL-17REL homologue from large yellow croaker and named it as LycIL-17REL. The deduced open reading frame （ORF） of LycIL-17REL is 1 659 nucleotides （nt）， encoding a protein of 552 amino acids （aa） which consists of a signal peptide， an extracellular domain， a transmembrane region and an intracellular domain. The extracellular domain of LycIL-17REL possesses a FN I-like domain， while intracellular domain loses the SEFIR domain which is conserved in IL-17R family. Amino acid homology comparison shows that LycIL-17REL has 57-0% identity to Fugu（Takifugu rubripes） IL-17REL. Based on the structural and phylogenetic analysis， the vertebrate IL-17R family members were suggested to be classified into two groups: the IL-17RA/RB/RD group and the IL-17RC/RE/REL group. Besides this， we speculated that vertebrate IL-17REL and IL-17RE were probably differentiated the same ancestor from species older than teleosts. LycIL-17REL was constitutively expressed in all tissues tested， especially in mucosal related tissues such as intestine and gills. The up-regulated expression of LycIL-17REL was observed in head kidney and gills of large yellow croaker stimulated by Aeromonas hydrophila. These results suggested that LycIL-17REL may play an important role in the immune response against bacterial infection. |
| Key words: marine biology Larimichthys crocea IL-17REL molecular and expression evolution. |
