Three members in JAK/STAT signal pathway from the sea cucumber Apostichopus japonicus: Molecular cloning, characterization and function analysis
Three members in JAK/STAT signal pathway from the sea cucumber Apostichopus japonicus: Molecular cloning, characterization and function analysis
复制标题
海参JAK/STAT信号通路的三个成员：分子克隆、表征和功能分析。
DOI：
10.1016/j.fsi.2015.07.019
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发表时间：
2015-10-01
影响因子：
4.7
通讯作者：
Jin, Chunhua
中科院分区：
文献类型：
--
作者：
Shao, Yina;Li, Chenghua;Jin, Chunhua
JAK/STAT信号转导通路在宿主防御细菌感染中起着关键作用。本研究首次从仿刺参（Apostichopus）中克隆了JAK/STAT级联反应中3个分子STAT 5、FOXP和SOCS 2的全长cDNA（分别命名为AjSTAT 5、AjFOXP和AjSOCS 2），并研究了它们对灿烂弧菌（Vibrio splendidus）感染和LPS暴露的免疫功能。该基因全长2643 bp，含787个氨基酸残基，包括蛋白质相互作用结构域、STAT-a结构域、DNA结合结构域和SH 2结构域。推测的AjFOXP含有ZnF_C2H2结构域、亮氨酸拉链样结构域和FH结构域，这些结构域被认为是FOXP亚家族的代表性特征。AjSOCS 2的氨基酸序列与脊椎动物SOCS相似，含有SH 2结构域和SOCS box结构域。系统进化树进一步支持这3个蛋白均属于海参JAK/STAT信号通路的新成员。组织特异性表达分析表明，这三个基因在所有检测的组织中普遍表达。AjSTAT 5和AjFOXP均在肠、腱和呼吸树中优势表达，在肌肉中表达较弱。而AjSOCS 2在肌肉中的表达量最高，在呼吸树中的表达量最低。结果表明，在刺激条件下，AjSOCS 2、AjSTAT 5和AjFOXP的mRNA表达水平均显著上调，其中AjSOCS 2的表达水平与AjSTAT 5和AjFOXP的表达水平相反。siRNA沉默AjSTAT 5可抑制AjFOXP的表达，但可诱导AjSOCS 2的表达，提示AjSTAT 5可能直接调控AjFOXP，而AjSOCS 2主要通过抑制JAK/STAT通路发挥作用。本研究为进一步了解JAK/STAT信号转导通路在海参天然免疫应答中的作用奠定了基础。(C)2015爱思唯尔有限公司版权所有。
The JAK/STAT signal transduction pathway plays a critical role in host defense against bacterial infections. In the present study, we firstly cloned the full-length cDNAs of three molecules in JAK/STAT cascade, STAT5, FOXP and SOCS2, from sea cucumber Apostichopus japonicus (denoted as AjSTAT5, AjFOXP, AjSOCS2, respectively) and investigated their immune functions towards Vibrio splendidus infection and LPS exposure. The AjSTAT5 cDNA was composed of 2643 bp consisting of 787 amino acid residues which included protein interaction domain, STAT-a domain, DNA binding domain and SH2 domain. The putative AjFOXP contained a ZnF_C2H2 domain, the leucine zipper-like domain and FH domain, all of which were thought to be the representative characteristics of FOXP subfamily. The deduced amino acids sequence of AjSOCS2 included an SH2 domain and SOCS box domain similar to vertebrate SOCS counterparts. Phylogenetic trees further supported that all these three identified proteins belonged to novel members of JAK/STAT signal pathway in sea cucumber. Tissue specific expression analysis showed that three genes were ubiquitously expressed in all examined tissues. AjSTAT5 and AjFOXP were both dominantly expressed in intestine, tentacle and respiratory tree, and weak in muscle. In contrary, the peak expression of AjSOCS2 was observed in muscle and lowest in respiratory tree. The V. splendidus challenge and LPS exposure could both significantly up-regulate the mRNA expression of three genes, in which AjSOCS2 showed opposite expression trends to those of AjSTAT5 and AjFOXP. Silencing the AjSTAT5 by siRNA depressed the AjFOXP expression, but induced the expression level of AjSOCS2, revealing that AjSTAT5 might directly modulate AjFOXP, and AjSOCS2 function primarily by acting as a potent inhibitor involve in JAK/STAT pathway. The present study would expand our understanding on JAK/STAT signaling transduction pathway in modulating the innate immune responses of sea cucumber. (C) 2015 Elsevier Ltd. All rights reserved.