Jang Ju Hye, Kim Hyun, Kim Yu Jin, Cho Ju Hyun
Research Institute of Life Science, Gyeongsang National University, Jinju 52828, South Korea.
Division of Life Science, Gyeongsang National University, Jinju 52828, South Korea.
Fish Shellfish Immunol. 2016 Apr;51:53-63. doi: 10.1016/j.fsi.2016.02.012. Epub 2016 Feb 10.
NOD1 has important roles in innate immunity as sensor of microbial components derived from bacterial peptidoglycan. In this study, we identified genes encoding components of the NOD1 signaling pathway, including NOD1 (OmNOD1) and RIP2 (OmRIP2) from rainbow trout, Oncorhynchus mykiss, and investigated whether OmNOD1 has immunomodulating activity in a rainbow trout hepatoma cell line RTH-149 treated with NOD1-specific ligand (iE-DAP). The deduced amino acid sequence of OmNOD1 contained conserved CARD, NOD and LRR domains. Loss-of-function and gain-of-function experiments indicated that OmNOD1 is involved in the expression of pro-inflammatory cytokines. Silencing of OmNOD1 in RTH-149 cells treated with iE-DAP decreased the expression of IL-1β, IL-6, IL-8 and TNF-α. Conversely, overexpression of OmNOD1 resulted in up-regulation of IL-1β, IL-6, IL-8 and TNF-α expression. In addition, RIP2 inhibitor (gefitinib) significantly decreased the expression of these pro-inflammatory cytokines induced by iE-DAP in RTH-149 cells. These findings highlight the important role of NOD1 signaling pathway in fish in eliciting innate immune response.
NOD1作为细菌肽聚糖衍生的微生物成分的传感器，在先天免疫中发挥着重要作用。在本研究中，我们从虹鳟（Oncorhynchus mykiss）中鉴定出编码NOD1信号通路成分的基因，包括NOD1（OmNOD1）和RIP2（OmRIP2），并研究了在用NOD1特异性配体（iE-DAP）处理的虹鳟肝癌细胞系RTH-149中，OmNOD1是否具有免疫调节活性。OmNOD1推导的氨基酸序列包含保守的CARD、NOD和LRR结构域。功能丧失和功能获得实验表明，OmNOD1参与促炎细胞因子的表达。在用iE-DAP处理的RTH-149细胞中，沉默OmNOD1可降低IL-1β、IL-6、IL-8和TNF-α的表达。相反，过表达OmNOD1导致IL-1β、IL-6、IL-8和TNF-α表达上调。此外，RIP2抑制剂（吉非替尼）显著降低了iE-DAP在RTH-149细胞中诱导的这些促炎细胞因子的表达。这些发现突出了NOD1信号通路在鱼类引发先天免疫反应中的重要作用。
