In mammals, the transcription factors paired box-5 (Pax-5) and B-lymphocyte-induced maturation protein-1 (Blimp-1) maintain strict command of B-cell differentiation from hematopoietic stem cells to plasma cells. Here, we identified the Pax-5 and Blimp-1 genes and their predicted proteins in the orange-spotted grouper (Epinephelus coioides). Grouper Pax-5 was predicted to contain a paired box domain and a positive regulator domain, and five zinc fingers were predicted in grouper Blimp-1. Sequence alignment revealed that grouper Pax-5 and Blimp-1 shared a high sequence identity with that of other teleosts, particularly in the functional motifs. Tissue distribution analysis demonstrated that all tissues studied from healthy grouper expressed Pax-5 and Blimp-1. Pax-5 had the highest expression in vital lymphoid tissues (p < 0.05), whereas Blimp-1 expression was relatively equal among tissues (p> 0.05). In view of the conserved functions of Pax-5 and Blimp-1, we studied the progression of B cell differentiation in mucosal and systematic immunity by detecting the expression of these genes after infection with the parasite Cryptocaryon irritans and following vaccination with Vibrio harveyi. The expression level of grouper Blimp-1, IgM and IgT were significantly upregulated (p < 0.05), and the response occurred earlier in the systemic immune than the mucosal immune.

在哺乳动物中，成对的转录因子与box-5（Pax-5）和B淋巴细胞诱导的成熟蛋白1（Blimp-1）配对，可以严格控制B细胞从造血干细胞分化为浆细胞的过程。在这里，我们在橙色斑斑的石斑鱼（Epinephelus coioides）中鉴定了Pax-5和Blimp-1基因及其预测的蛋白质）。石斑鱼Pax-5预计包含成对的框结构域和一个正调节域，并且在石斑鱼Blimp-1中预计有五个锌指。序列比对显示，石斑鱼Pax-5和Blimp-1与其他硬骨鱼有着高度的序列同一性，特别是在功能性基序中。组织分布分析表明，健康石斑鱼研究的所有组织均表达Pax-5和Blimp-1。Pax-5在重要淋巴组织中的表达最高（p <0.05），而Blimp-1在组织中的表达相对相等（p > 0.05）。鉴于Pax-5和Blimp-1的保守功能，我们通过检测寄生虫感染后这些基因的表达，研究了粘膜和系统免疫中B细胞分化的进程隐孢子虫irritans以及接种哈维弧菌的疫苗。石斑鱼Blimp-1，IgM和IgT的表达水平显着上调（p <0.05），并且在全身免疫中比粘膜免疫更早发生反应。