不同病原菌刺激下三疣梭子蟹主要组织LGBP基因的时序表达

脂多糖-β-1,3-葡聚糖结合蛋白（lipopolysaccharide-β-1,3-glucan binding protein,LGBP）作为一种模式识别受体能够识别革兰氏阴性菌和真菌的细胞壁多糖成分脂多糖和β-1,3-葡聚糖,在甲壳动物的免疫系统中占有重要地位,为了解LGBP在蟹类动物抗菌免疫应答中的作用,采用SYBR Green I实时荧光定量PCR方法,对分别经溶藻弧菌,酵母菌,溶-酵混合菌、金黄色葡萄球菌刺激6 h、12 h、24 h、48 h的三疣梭子蟹血细胞、肝胰腺、肌肉3种组织LGBP基因的相对表达量进行了检测。结果显示,LGBP基因在3种组织中的时序表达量总体趋势基本一致,呈现＂上升-下降-再上升-下降＂的趋势,各实验组在实验6 h时表达量均达到了峰值;不同病原菌刺激下LGBP基因在梭子蟹肝胰腺和血细胞中的表达量明显高于肌肉,且溶-酵混合菌刺激组织LGBP的表达量最高,酵母菌和溶藻弧菌刺激组次之,金黄色葡萄球菌组最低,说明LGBP主要参与蟹类抵抗革兰氏阴性菌和真菌侵入的免疫防御反应,但对革兰氏阳性菌也有一定的作用。

Temporal expression of the LGBP gene in mainly tissues of Portunus trituberculatas challenged by different pathogens

LGBP（ lipopolysaccharide-β-1,3-glucan binding protein） is a pattern recognition receptor involving the recognition of lipopolysaccharide and β-1,3-glucan from Gram-negative bacteria and fungal cells. It acts as a important role in innate immunity of crustacean. The study investigated the relative expressions of the LGBP gene in hemocytes,hepatopancreas and muscle of Portunus trituberculatas with real-time qPCR,and the crabs were infected with Vbrio alginolyticus,Candida lusitaniae,mixed Vibrio alginolyticus and Candida lusitaniae,and Staphyloccocus aureus,respectively. The results showed that the overall trend of the relative expressions of the LGBP gene in three tissues was consistent,showing up-down then up-down trend. The LGBP gene expressed highest at 6 h post-injection in each group,and expressed significantly higher in hemocytes and hepatopancreas than in muscle,with the highest level observed in Vibrio alginolyticus-injected group,and the lowest level was found in Staphyloccocus aureus-injected group.