基于肠转录组学探究NaHCO3碱度胁迫下红罗非鱼应激响应与耐受机制  

Transcriptomic analysis of stress response and tolerance mechanisms in the intestine of red tilapia(Oreochromis spp.)during NaHCO3 exposure

作　　者：陶易凡 曹巍 华吉祥 李祖辰 姜冰洁 张会昆 马雪彬 路思琪 强俊[1] TAO Yifan;Cao Wei;HUA Jixiang;LI Zuchen;JIANG Bingjie;ZHANG Huikun;MA Xuebin;LU Siqi;QIANG Jun(Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization,Ministry of Agriculture and Rural Affairs,Freshwater Fisheries Research Center,Chinese Academy of Fishery Sciences,Wuxi 214081,China;Hebei Key Laboratory of the Bohai Sea Fish Germplasm Resources Conservation and Utilization,Beidaihe Central Experimental Station,Chinese Academy of Fishery Sciences,Qinhuangdao 066100,China;Tangshan Aquatic Products Technology Promotion Station,Tangshan 063200,China;Cangzhou Academy of Agricultural and Forestry Sciences,Cangzhou 061001,China)

机构地区：[1]中国水产科学研究院淡水渔业研究中心,农业农村部淡水渔业与种质资源利用重点实验室,江苏无锡214081 [2]中国水产科学研究院北戴河中心实验站,河北省渤海鱼类种质资源保护与利用重点实验室,河北秦皇岛066100 [3]唐山市水产技术推广站,河北唐山063200 [4]沧州市农林科学院,河北沧州061001

出　　处：《中国水产科学》2024年第8期897-909,共13页Journal of Fishery Sciences of China

基　　金：国家重点研发计划-政府间国际科技创新合作重点专项(2022YFE0139600);农业生物育种重大专项(2023ZD04065)。

摘　　要：为探究红罗非鱼(Oreochromisspp.)对NaHCO3碱度胁迫的应激响应机制,本研究以初始体重为(73.43±1.62)g的红罗非鱼作为研究对象,进行40 d NaHCO3碱度胁迫,比较NaHCO3碱度胁迫组[CA,(35.51±0.17)mmol/L]和淡水对照组[Con,(1.75±0.08)mmol/L]红罗非鱼血清生理参数、肠组织学和肠转录组差异。结果显示,红罗非鱼血清过氧化氢酶(CAT)活性与总抗氧化能力(TAOC)、丙二醛(MDA)、血氨和尿素氮(BUN)水平在碱度胁迫下显著增加(P<0.05);碱度胁迫导致红罗非鱼肠绒毛缩短和肠上皮损伤等现象的发生;肠转录组学分析共获得2853个差异表达基因,其中上调基因1674个,下调基因1179个。富集分析揭示了红罗非鱼肠组织响应碱胁迫的关键通路(内吞作用、氨基酸生物合成和IgA生成相关肠道免疫网络等),这些途径主要涉及物质跨膜运输、能量代谢和免疫响应等生物学过程。qRT-PCR检测验证12个碱应激响应关键基因转录水平的表达。结果表明,碱度胁迫会损伤红罗非鱼肠道组织结构,并造成其氧化应激;肠道运输、代谢和免疫响应关键基因表达的变化是红罗非鱼耐受高碱度环境的重要策略,本研究结果能够为阐释红罗非鱼对环境碱度的适应性调节机制提供理论参考。The diminishing availability of freshwater resources in recent years has led to a decrease in suitable areas for freshwater aquaculture,which in turn has prompted the use of saline-alkaline water to meet the growing demands.However,the limited application of saline-alkaline water,threatened by the presence of a single species in saline-alkaline aquaculture,notably impedes the development of saline-alkaline aquaculture.A comprehensive understanding of their physiological and molecular mechanisms of salt-alkaline tolerance is essential to cultivate species suitable for saline-alkaline aquaculture.Red tilapia(Oreochromis spp.)has good salinity tolerance;however,the metabolic response of red tilapia under an alkaline environment remains largely unclear.In this study,we compared serum physiological parameters,intestinal histology,and transcriptome in red tilapia between an alkalinity stress group[CA,(35.51±0.17)mmol/L]and a freshwater control group[Con,(1.75±0.08)mmol/L].Exposure to the alkalinity condition for 40 d resulted in increased serum catalase(CAT)activity,total antioxidant capacity(TAOC),malondialdehyde(MDA),ammonia,and urea nitrogen(BUN)levels(P<0.05),indicating an imbalance in ammonia excretion and antioxidant defense occurred in red tilapia under alkalinity stress;notable damage to intestinal fluff,thinning of the intestinal muscle layer,and damage to intestinal epithelial cells were also observed in the CA group,suggesting that alkalinity stress may disrupt normal gut physiological function.To investigate potential regulatory mechanisms associated with the observed biochemical and morphological alterations,we conducted a transcriptome analysis.Principal component analysis(PCA)revealed a clear separation of the samples from each group,suggesting high-quality data.Based on a log2(fold change)of≥1 or≤−1 and P<0.05,we identified a total of 2853 differentially expressed genes(CA vs.Con),including 1674 upregulated and 1179 downregulated genes.A total of 234 Gene Ontology(GO)items were found to be signi

关 键 词：红罗非鱼 碱度胁迫 转录组测序 肠道 盐碱水 

分 类 号：S917[农业科学—水产科学]