稀有鮈鲫芳香化酶基因的表达及内分泌干扰物(EDCs)暴露对其表达的影响

Expression of Cytochrome P450 Aromatase Genes and Effects of EDCs Exposure on Their Expression in Rare Minnow(Gobiocypris rarus)

克隆稀有鮈鲫芳香化酶基因（cyp19a和cyp19b）片段,半定量方法检测其组织表达特异性,实时定量PCR检测2基因在孵化后18~50 d幼鱼的发育阶段表达情况,对成鱼进行3 d的乙炔基雌二醇（EE2,1 nmol/L）和壬基酚（NP,1μmol/L）药物暴露试验,实时定量PCR检测它们对2个基因表达的影响。结果显示,克隆获得759 bp的cyp19a和407 bp的cyp19b片段,cyp19a主要在卵巢中表达,cyp19b主要在脑中表达。在幼鱼发育阶段,cyp19a的表达没有显著差异,cyp19b在38 d后出现明显的下降;成体稀有鮈鲫cyp19a受到EE2极显著抑制（0.23倍,P〈0.01）,但NP抑制效果不显著（0.59倍）,cyp19b在EE2和NP暴露后都有上调的趋势（1.83、1.02倍）。说明cyp19基因可以作为EDCs的作用靶分子,有助于对高等脊椎动物包括人类进行预测和风险评估。

Two cytochrome P450 aromatase gene fragments（cyp19a,cyp19b） were cloned from ovary and brain in rare minnow respectively.The tissue distribution was studied using RT-PCR method.By real-time PCR,the expression of cyp19 in developing fish from 18 to 50 days after hatching was measured.After 3-day exposure of EE2（1 nmol/L） and NP（1 μmol/L） in adult rare minnow,the effects on cyp19 genes were studied using real-time PCR.The results show 759 bp of cyp19 a and 407 bp of cyp19b were cloned from rare minnow.cyp19a and cyp19b were predominantly expressed in ovary and brain respectively.There was no significant difference of cyp19a in developing fish,while cyp19b was significantly declined from fish of 38 d.cyp19 a in adult rare minnow was quite significantly depressed by EE2（0.23 fold,P0.01）,but not by NP.EE2 and NP had no significant effects on cyp19b with an increasing trend（1.83 fold,1.02 fold）.The results revealed that cyp19 can be a target molecular for EDCs（endocrine disrupting chemicals）.And it also helps to predict the adverse effects of EDCs on vertebrate and human.