Zhang Xiumei, Zhang Pengjuan, Li Chenghua, Li Ye, Jin Chunhua, Zhang Weiwei
School of Marine Sciences, Ningbo University, Ningbo, Zhejiang Province 315211, China.
School of Marine Sciences, Ningbo University, Ningbo, Zhejiang Province 315211, China.
Dev Comp Immunol. 2015 Jan;48(1):138-42. doi: 10.1016/j.dci.2014.10.001. Epub 2014 Oct 13.
The TNF-α signaling cascade is involved in the regulation of a variety of biological processes, including cell proliferation, differentiation, apoptosis and the immune response in vertebrates. Here, two regulatory genes, lipopolysaccharide-induced tumor necrosis factor α factor (LITAF) and baculoviral inhibitor of apoptosis repeat-containing 2 (BIRC2), were identified in coelomocytes from the sea cucumber Apostichopus japonicus by RNA-seq and RACE (denoted as AjLITAF and AjBIRC2, respectively). The full-length cDNA of AjLITAF was 1417 bp, with a 5' untranslated region (UTR) of 189 bp, a 3' UTR of 637 bp with one cytokine RNA instability motif (ATTTA) and an open reading frame (ORF) of 591 bp encoding a polypeptide of 196 amino acid residues and a predicted molecular weight of 22.1 kDa. The partial AjBIRC2 cDNA was 2324 bp with a 5' UTR of 145 bp, a 3' UTR of 469 bp and a complete ORF of 1710 bp encoding a polypeptide of 569 amino acid residues. Analysis of the deduced amino acid sequences revealed that both genes shared a remarkably high degree of structural conservation with their mammalian orthologs, including a highly conserved LITAF domain in AjLITAF and three types of BIR domains in AjBIRC2. Spatial expression analysis revealed that AjLITAF and AjBIRC2 were expressed at a slightly lower level in the intestine and tentacle tissues compared with the other four tissues examined. After challenging the sea cucumbers with Vibrio splendidus, the expression levels of AjLITAF and AjBIRC2 in coelomocytes were increased by 2.65-fold at 6 h and 1.76-fold at 24 h compared with the control group. In primary cultured coelomocytes, a significant increase in the expression of AjLITAF and AjBIRC2 was detected after 6 h of exposure to 1 µg mL(-1) LPS. Together, these results suggest that AjLITAF and AjBIRC2 might be involved in the sea cucumber immune response during the course of a pathogenic infection or exposure to pathogen-associated molecular pattern (PAMP) molecules.
肿瘤坏死因子-α（TNF-α）信号级联反应参与调控多种生物学过程，包括脊椎动物的细胞增殖、分化、凋亡及免疫反应。在此，通过RNA测序和RACE技术，在仿刺参体腔细胞中鉴定出两个调控基因，即脂多糖诱导肿瘤坏死因子α因子（LITAF）和含杆状病毒凋亡抑制重复序列2（BIRC2）（分别命名为AjLITAF和AjBIRC2）。AjLITAF的全长cDNA为1417 bp，5'非翻译区（UTR）为189 bp，3'UTR为637 bp，带有一个细胞因子RNA不稳定基序（ATTTA），开放阅读框（ORF）为591 bp，编码一个由196个氨基酸残基组成的多肽，预测分子量为22.1 kDa。AjBIRC2的部分cDNA为2324 bp，5'UTR为145 bp，3'UTR为469 bp，完整的ORF为1710 bp，编码一个由569个氨基酸残基组成的多肽。对推导的氨基酸序列分析表明，这两个基因与其哺乳动物直系同源基因在结构上具有高度的保守性，包括AjLITAF中高度保守的LITAF结构域和AjBIRC2中的三种BIR结构域。空间表达分析显示，与所检测的其他四种组织相比，AjLITAF和AjBIRC2在肠和触手组织中的表达水平略低。用灿烂弧菌攻击海参后，与对照组相比，体腔细胞中AjLITAF和AjBIRC2的表达水平在6小时时增加了2.65倍，在24小时时增加了1.76倍。在原代培养的体腔细胞中，暴露于1 μg mL(-1)脂多糖6小时后，检测到AjLITAF和AjBIRC2的表达显著增加。综上所述，这些结果表明AjLITAF和AjBIRC2可能在致病性感染或暴露于病原体相关分子模式（PAMP）分子过程中参与海参的免疫反应。
