College of Animal Sciences, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China.
College of Animal Sciences, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China.
Dev Comp Immunol. 2019 Dec;101:103452. doi: 10.1016/j.dci.2019.103452. Epub 2019 Jul 15.
NFIL3 is a transcriptional activator of the IL-3 promoter in T cells. In vertebrates, it has been characterized as an essential regulator of several cellular processes such as immunity response, apoptosis and NK cells maturation. However, the identification and functional characterization of NFIL3 still remains unclear in arthropods. In this study, the NFIL3 homologue was firstly cloned and characterized in mud crab Scylla paramamosain. The full-length of SpNFIL3 was 2, 041 bp in length with an open reading frame of 1, 509 bp, containing a conserved basic region of leucin zipper domain. The qRT-PCR analysis indicated that SpNFIL3 was significantly highly expressed in hepatopancreas and in hemocytes. Moreover, the SpNFIL3 transcription could be up-regulated after the challenge of Vibrio alginolyticus or virus-analog Poly (I:C). The dual-luciferase reporter assays revealed that SpNFIL3 could activate NF-κB pathway. The immunofluorescence assay indicated SpNFIL3 was located in nucleus. After NFIL3 was interfered in vivo and in vitro, the expressions of two NF-κB members (SpRelish and SpDorsal), six antimicrobial peptide genes (SpCrustin and SpALF2-6) and pro-inflammatory cytokine SpIL-16 were suppressed, and the bacteria clearance capacity of crabs was also markedly impaired in NFIL3 silenced crabs. These results indicated that SpNFIL3 played crucial role in the innate immunity of S. paramamosain and it also brought new insight into the origin and evolution of NFIL3 in arthropods and even in invertebrates.
NFIL3 是 T 细胞中 IL-3 启动子的转录激活因子。在脊椎动物中，它已被鉴定为几个细胞过程的必需调节剂，如免疫反应、细胞凋亡和 NK 细胞成熟。然而，在节肢动物中，NFIL3 的鉴定和功能特征仍然不清楚。在本研究中，首次在泥蟹 Scylla paramamosain 中克隆和表征了 NFIL3 同源物。SpNFIL3 的全长为 2041bp，开放阅读框为 1509bp，含有一个保守的亮氨酸拉链结构域的碱性区域。qRT-PCR 分析表明，SpNFIL3 在肝胰腺和血细胞中表达水平显著较高。此外，SpNFIL3 的转录可以在受到弧菌或病毒类似物 Poly (I:C) 挑战后上调。双荧光素酶报告基因检测显示 SpNFIL3 可以激活 NF-κB 途径。免疫荧光分析表明 SpNFIL3 位于细胞核内。在体内和体外干扰 NFIL3 后，两个 NF-κB 成员（SpRelish 和 SpDorsal）、六个抗菌肽基因（SpCrustin 和 SpALF2-6）和促炎细胞因子 SpIL-16 的表达受到抑制，并且 NFIL3 沉默蟹的细菌清除能力也明显受损。这些结果表明 SpNFIL3 在 S. paramamosain 的先天免疫中发挥着重要作用，它也为 NFIL3 在节肢动物甚至无脊椎动物中的起源和进化提供了新的见解。
