Interleukin-1 receptor antagonist (IL-1Ra) is an antagonist of IL-1β binding IL-1β receptors but does not induce intracellular responses or signal transduction. In this study, the full-length complementary DNA (cDNA) of the IL-1Ra gene (OaIL-1Ra) was identified from sheep (Ovis aries) using rapid amplification of cDNA ends PCR and submitted to GenBank with the accession number KC425613. The OaIL-1Ra cDNA comprised an open reading frame of 525 bp encoding a protein of 19765.8 Da, a 5′-untranslated region (UTR) of 27 bp, and a 3′-UTR of 676 bp with a poly(A) tail. Recombinant OaIL-1Ra with bioactivity was expressed in a prokaryotic expression system, and a monoclonal antibody against native OaIL-1Ra was prepared. Through Western blot analyses, the OaIL-1Ra protein was widely expressed in lung, heart, spleen, liver, kidney, muscle, intestine, lymphonodi, rumen, and white blood cells, with the highest levels in liver and spleen. The expression of OaIL-1Ra in primary cultured white blood cells of sheep were highly induced in a time-dependent manner when challenged with different bacteria. These results implied that OaIL-1Ra is associated with immune responses during bacterial infections.

中文翻译：

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绵羊（Ovis aries）的新型白介素-1受体拮抗剂的表征。

白介素-1受体拮抗剂（IL-1Ra）是与IL-1β结合的IL-1β受体的拮抗剂，但不诱导细胞内应答或信号转导。在这项研究中，通过快速扩增cDNA末端PCR从绵羊（Ovis aries）中鉴定出IL-1Ra基因（OaIL-1Ra）的全长互补DNA（cDNA），并提交给GenBank，登录号为KC425613。该OaIL素-1受体拮抗剂cDNA包含一个525 bp的开放阅读框，编码一个19765.8 Da的蛋白质，一个27'bp的5'-非翻译区（UTR），和一个带有poly（A）尾巴的676 bp的3'-UTR。在原核表达系统中表达具有生物活性的重组OaIL-1Ra，并制备了针对天然OaIL-1Ra的单克隆抗体。通过蛋白质印迹分析，OaIL-1Ra蛋白在肺，心脏，脾脏，肝脏，肾脏，肌肉，肠，淋巴结，瘤胃和白细胞中广泛表达，在肝脏和脾脏中含量最高。当用不同的细菌攻击时，OaIL-1Ra在绵羊原代培养的白细胞中的表达以时间依赖性方式被高度诱导。这些结果暗示OaIL-1Ra与细菌感染期间的免疫应答有关。