Isolation and characterization of Toll-like receptor 9 in half-smooth tongue sole Cynoglossus semilaevis
Isolation and characterization of Toll-like receptor 9 in half-smooth tongue sole Cynoglossus semilaevis
复制标题
半滑舌鳎Toll样受体9的分离和表征
DOI：
10.1016/j.fsi.2009.02.005
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发表时间：
2009-03-01
影响因子：
4.7
通讯作者：
Zhang, Quanqi
中科院分区：
文献类型：
--
作者：
Yu, Yan;Zhong, Qiwang;Zhang, Quanqi
Toll样受体（Toll like receptor，TLR）是机体天然免疫和适应性免疫的重要感受器，通过识别多种PAMP并启动信号转导而发挥作用。TLR 9作为TLR家族的一员，介导识别细菌和病毒基因组中常见的未甲基化CpG二核苷酸基序。本研究从半滑舌鳎（Cynoglossus semilaevis）中克隆了TLR 9基因。在4588 bp的基因组序列中，鉴定出3个外显子，2个内含子，5'端非翻译区长度为23 bp，3'端非翻译区长度为342 bp。推测的氨基酸序列长1062个残基，包括一个典型的保守的胞质Toll/白细胞介素-1受体（TIR）结构域，14个亮氨酸丰富的重复序列（LRR）基序，具有大于60%的同一性，以金头鲷鲷和日本比目鱼的直系同源物。定量RT-PCR分析表明，csTLR 9广泛表达，尤其是在脾脏和性腺。非活性鳗弧菌免疫后，脾脏和头肾中csTLR 9 mRNA水平未观察到统计学显著变化。In C.在半滑舌鳎个体发育中，csTLR 9的表达似乎受到发育调节。母体TLR 9 mRNA的存在和TLR 9在变态期表达的显著下降表明TLR 9可能参与了C.半滑舌鳎发育比较csTLR 9与哺乳动物和其他鱼类TLR 9的序列和表达谱表明，TLR 9的主要功能可能在脊椎动物中是保守的，尽管存在物种特异性特征。(C)2009爱思唯尔有限公司版权所有。
Toll-like receptors (TLRs) are considered as key sensors to trigger the host's innate immune system and adaptive immune responses by recognizing various PAMPs and initiating signal transduction. TLR9, as a member of TLR family, mediates the recognition of unmethylated CpG dinucleotide motifs commonly found in both bacterial and viral genomes. In the current study, the TLR9 gene was isolated from one of flatfish species, half-smooth tongue sole (Cynoglossus semilaevis). In the 4588 bp genomic sequence, three exons, two introns, and 5' UTR of 23 bp and 3' UTR of 342 bp were identified. Putative amino acid sequence was 1062 residues long, including a typical conserved cytosolic Toll/interleukin-1 receptor (TIR) domain, 14 leucine-rich repeat (LRR) motifs, with greater than 60% identity to gilthead sea bream Sparus aurata and Japanese flounder Paralichthys olivaceus orthologs. Quantitative RT-PCR analysis indicated a broad expression of csTLR9, especially in spleen and gonads. No statistically significant changes were observed for csTLR9 mRNA levels in spleen and head kidney after inactive Vibrio anguillarum immunisation. In C. semilaevis ontogeny, the expression of csTLR9 appeared to be developmentally regulated. The presence of maternal TLR9 mRNA and the dramatic decrease of TLR9 expression at metamorphic stage indicated TLR9 might be involved in C. semilaevis development. Comparing sequence and expression profile of csTLR9 with mammalian and other piscine TLR9s suggested that the main function of TLR9 might be conserved across vertebrates, although species-specific features were present. (C) 2009 Elsevier Ltd. All rights reserved.