【摘要】 为揭示大口黑鲈(Micropterus salmoides)MyD88基因结构特征及其在先天性免疫反应中的功能，本研究克隆了大口黑鲈MyD88的cDNA序列，通过荧光定量PCR分析MyD88 mRNA的组织分布及其对嗜水气单胞菌(Aeromonas hydrophila)感染的响应。结果表明，大口黑鲈MyD88CDS序列为867 bp,编码288个氨基酸，具有典型的死亡结构域和TIR(Toll/IL-1 receptor domain, TIR)结构域，其氨基酸序列与其他硬骨鱼类具有高度保守性，和小口黑鲈的同源性为99.5%。MyD88基因在大口黑鲈各组织均有表达，鳃中的表达量最高，其次为肝脏、皮肤和鳍条。经嗜水气单胞菌感染后，在肝脏、脾脏、肾脏和鳃中MyD88基因的相对表达量均显著上调，表明MyD88基因可能参与大口黑鲈抵御嗜水气单胞菌感染的免疫应答过程。本研究结果为探索MyD88基因在大口黑鲈先天免疫中的功能以及TLR信号通路中响应致病菌的作用提供参考。更多还原

【Abstract】 MyD88 is an adaptor molecule in toll-like receptor and interleukin-1 receptor signalling.There are many studies on the function of MyD88 in teleost fish, but few reports in largemouth bass.This study cloned the cDNA sequence of MyD88 in largemouth bass and analyzed the tissue distribution of MyD88 mRNA and its response to Aeromonas hydrophila infection using quantitative real-time PCR(qPCR) fluorescence analysis to elucidate the structural characteristics of the MyD88 gene and its function in innate immune responses in largemouth bass.The results showed that the cDNA sequence of MyD88 in largemouth bass was 867bp long, encoding 288 amino acids, with typical death domains and Toll/IL-1 receptor(TIR) domains.Its amino acid sequence exhibited high conservation among other teleost fishes, with a homology of 99.5% with that of smallmouth bass.The MyD88 gene was expressed in various tissues of largemouth bass, with the highest expression in the gills, followed by the liver, skin, and fins.After infection with hydrophila,the relative expression levels of the MyD88 gene were significantly upregulated in the liver, spleen, kidney, and gills.The results indicated that MyD88 gene was involved in the immune response of largemouth bass against Aeromonas hydrophila infection.This research provides insights into the function of the MyD88 gene in the innate immunity of largemouth bass and its role in responding to pathogenic bacteria in the Toll-like receptor(TLR) signalling pathway.更多还原