Department of Marine Life Sciences & Fish Vaccine Research Center, Jeju National University, Jeju Self-Governing Province 63243, Republic of Korea; Fish Vaccine Research Center, Jeju National University, Jeju Self-Governing Province 63243, Republic of Korea.
Department of Marine Life Sciences & Fish Vaccine Research Center, Jeju National University, Jeju Self-Governing Province 63243, Republic of Korea; Department of Ocean Sciences, Memorial University of Newfoundland, NL, A1C 5S7, Canada.
Fish Shellfish Immunol. 2017 Oct;69:128-141. doi: 10.1016/j.fsi.2017.08.015. Epub 2017 Aug 14.
Signal transducers and activators of transcription 1 (STAT1) is critically involved in mediating cytokine-driven signaling, and triggers the transcription of target genes to activate cellular functions. Although the structural and functional aspects of STAT members have been well described in mammals, only limited information is available for the STAT genes in teleost fishes. In the present study, two variants of STAT1 genes (RbSTAT1 and RbSTAT1L) were identified from rock bream and characterized at the cDNA and genomic sequence levels. RbSTAT1 and RbSTAT1L were found to share a common domain architecture with mammalian STAT1. Phylogenetic analysis revealed that RbSTAT1 shows a common evolutionary trajectory with other STAT1 counterparts, whereas RbSTAT1L showed a separate path, implying that it could be a novel member of the STAT family. The genomic organizations of RbSTAT1 and RbSTAT1L illustrated a similar exon-intron pattern with 23 exons in the coding sequence. Transcription factor-binding sites, which are mostly involved in the regulation of immune responses, were predicted at the putative promoter regions of the RbSTAT1 and RbSTAT1L genes. SYBR Green qPCR analysis revealed the ubiquitous expression of RbSTAT1 and RbSTAT1L transcripts in different fish tissues with the highest level observed in peripheral blood cells. Significantly modulated transcripts were noted upon viral (rock bream iridovirus [RBIV]), bacterial (Edwardsiella tarda and Streptococcus iniae), and pathogen-associated molecular pattern (lipopolysaccharide and poly I:C) stimulations. The WST-1 cell viability assay affirmed the potential antiviral capacity of RbSTAT1 and RbSTAT1L against RBIV. A possible role of RbSTAT1 and RbSTAT1L in the wound healing process was revealed according to their modulated expression in injured fish. In addition, the transcriptional regulation of RbSTAT1 and RbSTAT1L was analyzed by qPCR following stimulation with rock bream interleukin-10. Taken together, these findings suggest that the STAT1-mediated Janus kinase/STAT pathway might at least in part be involved in the regulatory mechanisms underlying the immune defensive roles against microbial pathogens and the wound healing process.
信号转导子和转录激活子 1（STAT1）在介导细胞因子驱动的信号转导中起着至关重要的作用，并触发靶基因的转录以激活细胞功能。尽管哺乳动物中 STAT 成员的结构和功能方面已经得到了很好的描述，但在鱼类中，STAT 基因的信息却很有限。在本研究中，从石斑鱼中鉴定出两种 STAT1 基因（RbSTAT1 和 RbSTAT1L），并在 cDNA 和基因组序列水平上进行了表征。RbSTAT1 和 RbSTAT1L 被发现具有与哺乳动物 STAT1 共同的结构域架构。系统发育分析表明，RbSTAT1 与其他 STAT1 同源物具有共同的进化轨迹，而 RbSTAT1L 则表现出不同的路径，表明它可能是 STAT 家族的一个新成员。RbSTAT1 和 RbSTAT1L 的基因组组织显示出相似的外显子-内含子模式，编码序列中有 23 个外显子。预测 RbSTAT1 和 RbSTAT1L 基因的启动子区域存在大多数参与免疫反应调节的转录因子结合位点。SYBR Green qPCR 分析显示，RbSTAT1 和 RbSTAT1L 转录本在不同鱼类组织中广泛表达，在外周血中表达水平最高。在病毒（石斑鱼虹彩病毒[RBIV]）、细菌（迟缓爱德华氏菌和鳗弧菌）和病原体相关分子模式（脂多糖和聚 I:C）刺激下，转录本显著调节。WST-1 细胞活力测定证实了 RbSTAT1 和 RbSTAT1L 对 RBIV 的潜在抗病毒能力。根据它们在受伤鱼类中的表达模式，揭示了 RbSTAT1 和 RbSTAT1L 在伤口愈合过程中的可能作用。此外，通过石斑鱼白细胞介素-10 刺激后的 qPCR 分析了 RbSTAT1 和 RbSTAT1L 的转录调控。综上所述，这些发现表明，STAT1 介导的 Janus 激酶/STAT 通路至少部分参与了对微生物病原体的免疫防御作用和伤口愈合过程的调节机制。
