【作者】 刘文生； 姜丽娟； 王娟； 饶飞翔； 李美娟；

【Author】 Liu Wensheng,Jiang Lijuan,Wang Juan,Rao Feixiang,Li Meijuan(College of Animal Sciences,South China Agricultural University,Guangzhou 510642,China)

【机构】 华南农业大学动物科学学院；

【摘要】 根据已知的黄颡鱼(Pelteobagrus fulvidraco)生长激素(GH)基因cDNA序列,把黄颡鱼GH成熟肽的cDNA定向插入表达载体pET-28a,转化到大肠杆菌BL21(DE3)。用IPTG诱导重组蛋白表达,SDS-PAGE分析表明黄颡鱼GH以融合蛋白的形式得到了表达,分子量约为20.4KD,与预期的大小一致。在IPTG终浓度1.0mmol/L、温度37℃和培养时间4h的最佳诱导表达条件下,黄颡鱼生长激素基因在大肠杆菌中获得高效表达,其表达量占细胞蛋白总量38%,主要为不溶性的包涵体。养殖试验在室内循环水养殖系统中进行,分别使用0ppm、1ppm、5ppm、10ppm的生长激素对黄颡鱼鱼苗进行浸泡处理,每7d浸泡一次,共浸泡4周。结果表明,1ppm组增重率和特定生长率分别比对照组提高了16.43%(P<0.05)、6.2%(P>0.05);5ppm组增重率和特定生长率分别比对照组提高了11.81%(P<0.05)、4.6%(P>0.05),其他组与对照组没有明显差异。更多还原

【Abstract】 The Pelteobagrus fulvidraco GH cDNA fragment was inserted into pET-28a to construct the expression plasmid,then transformed the expression plasmid into E.coli BL21(DE3) competent cells.The mRNA and expressed protein were assayed by SDS-PAGE.The results showed that a new Protein band was found in SDS-PAGE with molecular mass of about 20.4KD.The recombinant protein largely expressed at 37℃,with 1mmol/L IPTG when induced 4h.Feeding trials were conducted in indoor circulating water cultivation system.Every seven days the four groups respectively soaking the Pelteobagrus fulvidraco GH concentration of 0ppm,1ppm,5ppm and 10ppm,every group soaks four times.The results show that 1ppm group fishes was higher in weight gain(WG) and specific growth rate(SGR),respectively 16.43%(P<0.05) and 6.2%(P>0.05) higher than control group.The 5ppm group fishes was higher in weight gain(WG) and specific growth rate(SGR),respectively 11.81%(P<0.05) and 4.6%(P>0.05) higher than control group.The 10ppm group had no significant difference with the control group.更多还原