Polian vesicle is thought to produce coelomocytes and contribute to the sea cucumber's immune system. Our previous work has indicated that polian vesicle was responsible for cell proliferation at 72 h post pathogenic challenge. However, the transcription factors related to the activation of effector factors and the molecular process behind this remained unknown. In this study, to reveal the early functions of polian vesicle in response to the microbe, a comparative transcriptome sequencing of polian vesicle in V. splendidus-challenged Apostichopus japonicus, including normal group (PV 0 h), pathogen challenging for 6 h (PV 6 h) and 12 h (PV 12 h) was performed. Compared PV 0 h to PV 6 h, PV 0 h to PV 12 h, and PV 6 h to PV 12 h, we found 69, 211, and 175 differentially expressed genes (DEGs), respectively. KEGG enrichment analysis revealed the DEGs, including several transcription factors such as fos, FOS-FOX, ATF2, egr1, KLF2, and Notch3 between PV 6 h and PV 12 h were consistently enriched in MAPK, Apelin and Notch3 signaling pathways related to cell proliferation compared with that in PV 0 h. Important DEGs involved in cell growth were chosen, and their expression patterns were almost the same as the transcriptome profile analysis by qPCR. Protein interaction network analysis indicated that two DEGs of fos and egr1 were probably significant as key candidate genes controlling cell proliferation and differentiation in polian vesicle after pathogenic infection in A. japonicus. Overall, our analysis demonstrates that polian vesicles may play an essential role in regulating proliferation via transcription factors-mediated signaling pathway in A. japonicus and provide new insights into hematopoietic modulation of polian vesicles in response to pathogen infection.

Polian 囊泡被认为可以产生体腔细胞并有助于海参的免疫系统。我们之前的工作表明，多糖小泡负责致病性攻击后 72 小时的细胞增殖。然而，与效应因子激活相关的转录因子及其背后的分子过程仍然未知。在这项研究中，为了揭示 polian 囊泡响应微生物的早期功能，对V. splendidus攻击的刺参中的 polian 囊泡进行了比较转录组测序，包括正常组（PV 0 h），病原体攻击 6 h（PV 6 h）和 12 h（PV 12 h）。比较 PV 0 h 到 PV 6 h、PV 0 h 到 PV 12 h 和 PV 6 h 到 PV 12 h，我们分别发现了 69、211 和 175 个差异表达基因 (DEG)。KEGG 富集分析显示，DEGs，包括几个转录因子，如 fos、FOS-FOX、ATF2、egr1、KLF2 和 PV 12 小时之间的 Notch3，在MAPK 、Apelin 和 Notch3中持续富集细胞增殖相关信号通路与PV 0 h相比。选择了参与细胞生长的重要 DEG，它们的表达模式与 qPCR 的转录组谱分析几乎相同。蛋白质相互作用网络分析表明，fos和egr1的两个DEGs可能作为控制刺参病原体感染后多囊泡细胞增殖和分化的关键候选基因具有重要意义。总的来说，我们的分析表明，多囊泡可能通过转录因子介导的信号通路在刺参中调节增殖中发挥重要作用，并为多囊泡响应病原体感染的造血调节提供新的见解。