Guo Minglan, Wei Jingguang, Zhou Yongcan, Qin Qiwei
Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, PR China; Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, PR China.
State Key Laboratory Breeding Base for Sustainable Exploitation of Tropical Biotic Resources, College of Marine Science, Hainan University, Haikou 570228, PR China.
Fish Shellfish Immunol. 2016 Feb;49:355-63. doi: 10.1016/j.fsi.2015.12.001. Epub 2015 Dec 9.
c-Jun N-terminal kinase 2 (JNK2) is a multifunctional mitogen-activated protein kinases involving in cell differentiation and proliferation, apoptosis, immune response and inflammatory conditions. In this study, we reported a new JNK2 (Ec-JNK2) derived from orange-spotted grouper, Epinephelus coioides. The full-length cDNA of Ec-JNK2 was 1920 bp in size, containing a 174 bp 5'-untranslated region (UTR), 483 bp 3'-UTR, and a 1263 bp open reading frame (ORF), which encoded a putative protein of 420 amino acids. The deduced protein sequence of Ec-JNK2 contained a conserved Thr-Pro-Tyr (TPY) motif in the domain of serine/threonine protein kinase (S-TKc). Ec-JNK2 has been found to involve in the immune response to pathogen challenges in vivo, and the infection of Singapore grouper iridovirus (SGIV) in vitro. Immunofluorescence staining showed that Ec-JNK2 was localized in the cytoplasm of grouper spleen (GS) cells, and moved to the nucleus after infecting with SGIV. Ec-JNK2 distributed in all immune-related tissues examined. After challenging with lipopolysaccharide (LPS), SGIV and polyriboinosinic polyribocytidylic acid (poly I:C), the mRNA expression of Ec-JNK2 was significantly (P < 0.01) up-regulated in juvenile orange-spotted grouper. Over-expressing Ec-JNK2 in fathead minnow (FHM) cells increased the SGIV infection and replication, while over-expressing the dominant-negative Ec-JNK2Δ181-183 mutant decreased it. These results indicated that Ec-JNK2 could be an important molecule in the successful infection and evasion of SGIV.
c-Jun氨基末端激酶2（JNK2）是一种多功能丝裂原活化蛋白激酶，参与细胞分化与增殖、细胞凋亡、免疫反应及炎症状态。在本研究中，我们报道了一种源自斜带石斑鱼（Epinephelus coioides）的新型JNK2（Ec-JNK2）。Ec-JNK2的全长cDNA大小为1920 bp，包含一个174 bp的5'-非翻译区（UTR）、483 bp的3'-UTR以及一个1263 bp的开放阅读框（ORF），其编码一个由420个氨基酸组成的假定蛋白。Ec-JNK2推导的蛋白序列在丝氨酸/苏氨酸蛋白激酶（S-TKc）结构域中包含一个保守的苏氨酸-脯氨酸-酪氨酸（TPY）基序。已发现Ec-JNK2在体内参与对病原体攻击的免疫反应，并在体外参与新加坡石斑鱼虹彩病毒（SGIV）的感染。免疫荧光染色显示，Ec-JNK2定位于石斑鱼脾脏（GS）细胞的细胞质中，感染SGIV后转移至细胞核。Ec-JNK2分布于所有检测的免疫相关组织中。用脂多糖（LPS）、SGIV和聚肌苷酸-聚胞苷酸（poly I:C）刺激后，斜带石斑鱼幼鱼中Ec-JNK2的mRNA表达显著（P < 0.01）上调。在黑头软口鲦（FHM）细胞中过表达Ec-JNK会增加SGIV的感染和复制，而过表达显性负性Ec-JNK2Δ181-183突变体则会降低感染和复制。这些结果表明，Ec-JNK2可能是SGIV成功感染和逃避过程中的一个重要分子。
