Chen Xiao-Wu, Wei Qun, Wang Zhi-Peng, Wang Chun-Lei, Bi Yan-Hui, Gu Yi-Feng
Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, Shanghai Ocean University, Shanghai 201306, China.
Department of Surgical Oncology and Institute of Clinical Medicine, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, China; Department of Internal Medicine, University of Texas Southwestern Medical Center at Dallas, 6000 Harry Hines Boulevard, Dallas, TX 75390-9133, USA.
Dev Comp Immunol. 2016 Oct;63:1-9. doi: 10.1016/j.dci.2016.05.005. Epub 2016 May 12.
The interferon (IFN) regulatory factor 3 (IRF3) is a member of the IFN regulatory transcription factor family, which binds to the IFN-stimulated response element (ISRE) within the promoter of IFN genes and IFN-stimulated genes. In this study, the IRF3 cDNA of sea perch Lateolabrax maculatus (SpIRF3) was identified, which contained 1781 bp with an open reading frame of 1398 bp that coded a 465 amino acid protein. The SpIRF3 protein shared conserved characterizations with its homologues and displayed the conserved DNA-binding domain, IRF association domain, serine-rich C-terminal domain, and tryptophan residue cluster. Phylogenetic analysis illustrated that SpIRF3 belonged to the IRF3 subfamily. Subcellular localization analysis showed that SpIRF3 mainly resided in the cytoplasm without stimuli but translocated into nuclei in the presence of poly I:C. Real-time PCR data indicated that SpIRF3 was transcriptionally up-regulated by poly I:C stimulation in various organs. Moreover, reporter assay revealed that SpIRF3 functioned as a modulator in triggering the IFN response by inducing the activity of IFN and ISRE-containing promoter. These data revealed that SpIRF3 was a potential molecule in the IFN immune defense system against viral infection.
干扰素调节因子3（IRF3）是干扰素调节转录因子家族的成员，它与干扰素基因和干扰素刺激基因启动子中的干扰素刺激反应元件（ISRE）结合。在本研究中，鉴定了花鲈（Lateolabrax maculatus）的IRF3 cDNA（SpIRF3），其长度为1781 bp，开放阅读框为1398 bp，编码一个465个氨基酸的蛋白质。SpIRF3蛋白与其同源物具有保守特征，并具有保守的DNA结合结构域、IRF关联结构域、富含丝氨酸的C末端结构域和色氨酸残基簇。系统发育分析表明，SpIRF3属于IRF3亚家族。亚细胞定位分析表明，在无刺激时SpIRF3主要位于细胞质中，但在存在聚肌胞苷酸（poly I:C）时会转移到细胞核中。实时PCR数据表明，在各种器官中，poly I:C刺激可使SpIRF3转录上调。此外，报告基因检测显示，SpIRF3通过诱导含IFN和ISRE的启动子的活性，在触发IFN反应中起调节作用。这些数据表明，SpIRF3是干扰素免疫防御系统中抵抗病毒感染的一个潜在分子。
