Abstract In the present study, the complete characterization of cDNA and genomic sequences of IL-1β and IL-8, as well as the expression profile of these genes in the South American fish pacu (Piaractus mesopotamicus) is provided. The full-length pmIL-1β cDNA was composed of 1208 nucleotides that would produce a precursor peptide with 273 amino acid residues. A putative caspase-1 cleavage site, similar to what is found in mammalian IL-1β, was identified producing a mature peptide with a theoretical molecular weight of 17.21 kDa. The pmIL-8 cDNA sequence consisted of 1019 nucleotides which encoded a 95-amino acid protein with a theoretical molecular weight of 10.43 kDa that showed all typical CXC chemokine features, including a 20-residue signal peptide and four conserved cysteine residues. Constitutive mRNA expression was detected for both genes in the liver, head kidney, gill, intestine, skin and spleen. After a bacterial challenge, up-regulation was detected for both pmIL-1β and pmIL-8 in the spleen and head kidney at 12 h post-infection. At 24 h post-infection there was a decrease in the expression of both genes, with pmIL-8 showing a significant down-regulation in the liver and head kidney when compared to the control groups.

中文翻译：

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南美鱼类 Piaractus mesopotamicus 中促炎细胞因子 IL-1β 和 IL-8 的分子特征和基因表达分析

摘要 在本研究中，提供了 IL-1β 和 IL-8 的 cDNA 和基因组序列的完整表征，以及这些基因在南美太平洋鱼 (Piaractus mesopotamicus) 中的表达谱。全长 pmIL-1β cDNA 由 1208 个核苷酸组成，可产生具有 273 个氨基酸残基的前体肽。一个推定的 caspase-1 切割位点，类似于在哺乳动物 IL-1β 中发现的，被鉴定为产生理论分子量为 17.21 kDa 的成熟肽。pmIL-8 cDNA 序列由 1019 个核苷酸组成，编码 95 个氨基酸的蛋白质，理论分子量为 10.43 kDa，显示所有典型的 CXC 趋化因子特征，包括 20 个残基信号肽和四个保守的半胱氨酸残基。在肝脏、头肾、鳃、肠、皮肤和脾脏中检测到两种基因的组成型 mRNA 表达。在细菌攻击后，在感染后 12 小时检测到脾脏和头肾中 pmIL-1β 和 pmIL-8 的上调。感染后 24 小时，两种基因的表达均下降，与对照组相比，pmIL-8 在肝脏和头肾中显示出显着下调。