Transcriptomic and metabolomic insights into the role of the flgK gene in the pathogenicity of Pseudomonas plecoglossicida to orange-spotted grouper (Epinephelus coioides).
Transcriptomic and metabolomic insights into the role of the flgK gene in the pathogenicity of Pseudomonas plecoglossicida to orange-spotted grouper (Epinephelus coioides).
复制标题
转录组和代谢组学对FLGK基因在pseudomonas plecoglossicida对橙斑斑点（Epinephelus coioides）致病性中的作用的作用。
DOI：
10.24272/j.issn.2095-8137.2022.216
复制
发表时间：
2022-11-18
影响因子：
4.9
通讯作者：
中科院分区：
文献类型：
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作者：
杀舌假单胞菌是引起大黄鱼和斜带石斑鱼内脏白色斑点病的病原菌。此前，RNA测序显示，在感染过程中，在橙斑石斑鱼脾脏中，P. plecoglossicida flgK基因表达显著上调。为探讨flgK基因在杀多舌疫霉致病性中的作用，采用RNA干扰（RNAi）技术沉默flgK基因，筛选出沉默效率最高（89.40%）的突变株（flgK-RNAi株）进行进一步研究。结果表明，flgK基因沉默显著减弱了杀褶舌原杆菌的运动性、粘附性和生物膜形成。与用野生型杀舌类赤藓菌菌株感染的那些鱼相比，用flgK-RNAi菌株感染的橙斑石斑鱼显示存活率增加55%，首次死亡时间延迟一天，脾脏中的病原体更少，脾脏表面的白色斑点更少。flgK的RNAi显著影响了感染的橙斑石斑鱼脾脏的转录组和代谢组。京都基因和基因组百科全书（KEGG）富集分析显示，C型凝集素受体信号通路是变化最显著的免疫相关通路，丝裂原活化蛋白激酶（MAPK）信号通路与多种免疫相关通路相关。此外，精氨酸生物合成和甘油磷脂代谢是最显着改变的代谢相关途径。这些结果表明flgK是杀多舌类疫霉的一个毒力基因。此外，flgK似乎参与调节P. plecoglossicida中的运动性、粘附性和生物膜形成，以及调节橙斑石斑鱼对P. plecoglossicida感染的炎症和免疫应答。
Pseudomonas plecoglossicida is the pathogen responsible for visceral white spot disease in large yellow croaker (Larimichthys crocea) and orange-spotted grouper (Epinephelus coioides). Previously, RNA sequencing showed that P. plecoglossicida flgK gene expression was significantly up-regulated in orange-spotted grouper spleens during infection. To explore the role of flgK in P. plecoglossicida pathogenicity, RNA interference (RNAi) was performed to silence the P. plecoglossicida flgK gene, and the mutant (flgK-RNAi strain) with the best silencing efficiency (89.40%) was chosen for further study. Results showed that flgK gene silencing significantly attenuated P. plecoglossicida motility, adhesion, and biofilm formation. Compared to those fish infected with the wild-type strain of P. plecoglossicida, orange-spotted grouper infected with the flgK-RNAi strain showed a 55% increase in the survival rate and a one-day delay in time of first death, with fewer pathogens in the spleen and fewer white spots on the spleen surface. RNAi of flgK significantly affected the transcriptome and metabolome of the spleen in infected orange-spotted grouper. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis showed that the C-type lectin receptor signaling pathway was the most significantly changed immune-related pathway and the mitogen-activated protein kinase (MAPK) signaling pathway was related to multiple immune-related pathways. Furthermore, arginine biosynthesis and glycerophospholipid metabolism were the most significantly changed metabolism-related pathways. These findings suggest that flgK is a virulence gene of P. plecoglossicida. Furthermore, flgK appears to be involved in the regulation of motility, adhesion, and biofilm formation in P. plecoglossicida, as well as in the regulation of inflammatory and immune responses of orange-spotted grouper to P. plecoglossicida infection.