论文部分内容阅读
脂多糖-β-1,3-葡聚糖结合蛋白(LGBP)作为一种模式识别受体在甲壳动物的先天免疫中占有重要地位。利用SMART RACE技术,从三疣梭子蟹(Portunus trituberculatus)血细胞中克隆得到一条LGBP基因。该基因cDNA序列全长为1378bp,包括1095bp的开放阅读框(ORF),共编码365个氨基酸,在基因的5’端还含有138bp的非编码区(UTR),3’端含有144bp的UTR。预测的成熟肽相对分子质量为39825.24k,等电点为4.49。同时,用生物信息学方法对该基因的序列和二级结构进行了初步分析。RT-PCR结果显示:LGBP基因在被检测的组织,包括血细胞、肝胰腺、心脏、鳃和肌肉中都有表达。用金黄色葡萄球菌(Staphyloccocus aureus)和溶藻弧菌(Vibrio alginolyticus)刺激三疣梭子蟹后,发现在实验48h内,混合细菌刺激组血细胞中LGBP基因的表达量明显高于生理盐水对照组,推测该基因在抵抗细菌感染的免疫过程中发挥着积极的作用。
Lipopolysaccharide-β-1,3-glucan binding protein (LGBP), as a pattern recognition receptor, plays an important role in the innate immunity of crustacean. A LGBP gene was cloned from blood cells of Portunus trituberculatus using SMART RACE technology. The full-length cDNA sequence of this gene is 1378bp, including a 1095bp open reading frame (ORF) encoding a total of 365 amino acids. It also contains a 138bp non-coding region (UTR) at the 5 ’end of the gene and a 144 bp UTR at the 3’ end. The predicted relative molecular mass of mature peptide was 39825.24k, and the isoelectric point was 4.49. At the same time, bioinformatics methods were used to analyze the sequence and secondary structure of the gene. The result of RT-PCR showed that LGBP gene was expressed in the tested tissues, including blood cells, hepatopancreas, heart, gill and muscle. After Staphyloccocus aureus and Vibrio alginolyticus were stimulated with Portunus trituberculatus, the expression of LGBP in blood cells of mixed bacteria stimulation group was significantly higher than that of saline control group within 48h The gene plays an active role in the immune response against bacterial infections.