Abstract：
Phosphoribosyl pyrophosphate synthetases (EC 2.7.6.1) are key enzymes in the biological synthesis of phosphoribosyl pyrophosphate and are involved in diverse developmental processes. In our previous study, the PRPS1 gene was discovered as a key disease-resistance candidate gene in yellow drum, Nibea albiflora, in response to the infection of Vibrio harveyi, through genome-wide association analysis. This study mainly focused on the characteristics and its roles in immune responses of the PRPS1 gene in yellow drum. In the present study, the NaPRPS1 gene was cloned from yellow drum, encoding a protein of 320 amino acids. Bioinformatic analysis showed that NaPRPS1 was highly conserved during evolution. Quantitative RT-PCR demonstrated that NaPRPS1 was highly expressed in the head-kidney and brain, and its transcription and translation were significantly activated by V. harveyi infection examined by RT-qPCR and immunohistochemistry analysis, respectively. Subcellular localization revealed that NaPRPS1 was localized in cytoplasm. In addition, semi-in vivo pull-down assay coupled with mass spectrometry identified myeloid differentiation factor 88 (MyD88) as an NaPRPS1-interacting patterner, and their interaction was further supported by reciprocal pull-down assay and co-immunoprecipitation. The inducible expression of MyD88 by V. harveyi suggested that the linker molecule MyD88 in innate immune response may play together with NaPRPS1 to coordinate the immune signaling in yellow drum in response to the pathogenic infection. We provide new insights into important functions of PRPS1, especially PRPS1 in the innate immunity of teleost fishes, which will benefit the development of marine fish aquaculture.
摘要：
磷酸核糖焦磷酸合成酶（EC2.7.6.1）是磷酸核糖焦磷酸生物合成中的关键酶，并参与各种发育过程。在我们之前的研究中,PRPS1基因在黄鼓中被发现为关键的抗病候选基因，Nibeaalbiflora,为了应对哈维氏弧菌的感染，通过全基因组关联分析。本研究主要针对黄鼓PRPS1基因的特点及其在免疫应答中的作用进行研究。在本研究中,从黄鼓中克隆出NaPRPS1基因,编码320个氨基酸的蛋白质。生物信息学分析表明，NaPRPS1在进化过程中高度保守。定量RT-PCR显示NaPRPS1在头肾和脑中高表达,通过RT-qPCR和免疫组织化学分析检查，哈维氏弧菌感染显著激活了其转录和翻译，分别。亚细胞定位显示NaPRPS1定位于细胞质中。此外,与质谱联用的半体内下拉试验将骨髓分化因子88（MyD88）鉴定为NaPRPS1相互作用的模式，并且它们的相互作用得到了互惠下拉测定和免疫共沉淀的进一步支持。V.harveyi对MyD88的诱导型表达表明，先天免疫反应中的接头分子MyD88可能与NaPRPS1一起发挥作用，以协调黄鼓中的免疫信号，以响应病原体感染。我们为PRPS1的重要功能提供了新的见解，尤其是PRPS1在硬骨鱼的先天免疫中的作用，这将有利于海洋鱼类养殖的发展。
