文献类型：期刊文献

中文题名：胡子鲇脑型芳香化酶基因全长cDNA克隆及表达

英文题名：Molecular cloning and expression of Cyp19a1b cDNA in Clarias fuscus

作者：孙晶[1,2];李广丽[1,2];朱春华[1,2];吴天利[1,2];邓思平[1,2]

机构：[1]广东海洋大学水产学院,广东湛江524025;[2]南海水产经济动物增养殖广东普通高校重点实验室,广东海洋大学,广东湛江524025

年份：2012

卷号：19

期号：3

起止页码：408

中文期刊名：中国水产科学

外文期刊名：Journal of Fishery Sciences of China

收录：CSTPCD、、北大核心2011、Scopus、CSCD2011_2012、北大核心、CSCD

基金：广西科学研究与技术开发计划重点项目(桂科合1140009-4)

语种：中文

中文关键词：胡子鲇;P450芳香化酶基因;RT-PCR;性腺分化;表达

外文关键词：Clarias fuscus; Cypl 9al; RT-PCR; sex differentiation; mRNA expression

中文摘要：采用RT-PCR和RACE法,克隆了胡子鲇(Clarias fuscus)脑型芳香化酶基因Cyp19a1b,应用荧光实时定量PCR检测其在前脑、下丘脑、脑垂体、肝、精巢和卵巢6种组织,以及性腺分化前后(出膜后12～30 d)全鱼中的mRNA表达。结果表明,Cyp19a1b cDNA全长2 347 bp,5′端非编码区219 bp,3′端[不包括poly(A)]596 bp,开放阅读框(ORF)1 503 bp,编码500个氨基酸,推测其编码蛋白质分子量为56.388 kD。序列分析及分子系统进化树结果表明,胡子鲇Cyp19a1b氨基酸序列与非洲鲇(Clarias gariepinus)Cyp19a1b同源性最高,达95.6%;与南方大口鲇(Silurusmeridionalis)、黄颡鱼(Pelteobagrus fulvidraco)、斑马鱼(Danio rerio)、斑点叉尾(Ictalurus punctatus)、赤点石斑鱼(Epinephelus akaara)、鲤(Cyprinus carpio)、鲫(Carassius auratus)及稀有鲫(Gobiocypris rarus)Cyp19a1b同源性达75%以上,但与上述鱼类的性腺型芳香化酶基因(Cyp19a1a)同源性低于62%,表明其为脑型芳香化酶,同源性分析结果与根据传统形态学和生化特征分类的结果相一致。荧光实时定量PCR结果显示,Cyp19a1b在胡子鲇上述组织中均有表达,其中下丘脑中表达量最高,肝和精巢最低,在脑部的表达存在明显的性别差异(P<0.05)。此外,在胡子鲇性腺分化前(出膜后12 d)Cyp19a1b即开始表达,但分化前后表达量无显著性差异(P>0.05)。结果暗示Cyp19a1b可能不是引起胡子鲇性腺分化的直接因素,但其可能通过"下丘脑垂体性腺轴"对性腺分化过程产生间接影响。

外文摘要：A cDNA encoding Cypl9alb was derived from Clarius fuscus using RT-PCR and RACE. The cDNA was 2 347 bp with a 219 bp 5＇UTR, a 596 bp 3＇UTR （excluding poly （A））, and a 1 503 bp ORF, which encoded 500 amino acids and had a predicted mol wt of 56.388 kD. Sequence and phylogenetic analyses indicated that the C. fuscus Cypl9alb shared 95.6% sequence identity with clarias gariepinus and 〉75% identity with Silurus merid- ionalis, Pelteobagrus fulvidraco, Danio rerio, lctalurus punctatus, Cyprinus carpio, Carassius auratus, Gobio- cypris rarus, and Epinephelus akaara. In contrast, there was low sequence identity （〈62%） with Cypl9ala for these species. Therefore, the gene was classified into the Cyp19alb subfamily. This is consistent with the classifi- cation based on traditional morphology and biochemistry. Cyp19alb mRNA was expressed primarily in the fore- brain, hypothalamus, and pituitary, and to a lesser extent in the liver, testis and ovary. We observed differences in the level of expression in brain between males and females （P〈0.05）. Cyp19alb was expressed prior to sex dif- ferentiation in C. fuscus, but there was no difference in the level of expression between prior and post to sex dif- ferentiation （12-30 d after hatching）. Our results suggest that Cyp19alb is not directly involved in mediating sex differentiation in C. fuscus, but may t^lav an indirect role by acting on the hvoothalamic-oituitarv-lzonadal axis.