He Feng, Wen Hai Shen, Dong Shuang Lin, Shi Bao, Chen Cai Fang, Wang Lian Shun, Yao Jun, Mu Xing Jiang, Zhou Yu Guo
Key Laboratory of Mariculture Ministry of Education, Ocean University of China, Qingdao, 266003, People's Republic of China.
Fish Physiol Biochem. 2009 Aug;35(3):333-40. doi: 10.1007/s10695-008-9237-y. Epub 2008 Jun 7.
Cytochrome P450 aromatase, which is encoded by the CYP19a gene, converts androgens to estradiol. Considerable evidence suggests that estrogens play an important role in fish reproductive process. Therefore CYP19a is an excellent candidate gene for reproductive traits. Variants in the promoter of the CYP19a gene might also be involved in the control of aromatase expression and affect regulatory mechanism linking cholesterol metabolism to the synthesis of sex steroids. In this study, nine single-nucleotide polymorphisms (SNPs) were detected with polymerase chain reaction-single stranded conformational polymorphism (PCR-SSCP), namely A-680G, G-672A, AGTAGT-649 inserting or deleting, T-623C, C-410A, T7-454A, T-402C, TTTCCAGACTGA-345 inserting or deleting, and G-297C. Nine SNPs within the promoter of the CYP19a gene were tested for association with four reproductive traits [serum testosterone (T), serum 17beta-estradiol (E(2)), hepatosomatic index (HSI), and gonadosomatic index (GSI)] in a population of 50 female Japanese flounder individuals. A locus, P3 (TTTCCAGACTGA-345 inserting or deleting, G-297C), was significantly associated with 17beta-estradiol (E(2)) level (P < 0.05) in female Japanese flounder. In addition, there was significant association between one diplotype based on nine SNPs and reproductive trait. The genetic effect for E(2) level of diplotype D3 was significantly higher than those of other diplotypes (P < 0.05). Results indicate that these genetic effects of those variants on E(2) level may help to explain CYP19a gene status in the reproductive endocrinology of Japanese flounder.
细胞色素P450芳香化酶由CYP19a基因编码，可将雄激素转化为雌二醇。大量证据表明，雌激素在鱼类繁殖过程中发挥重要作用。因此，CYP19a是繁殖性状的一个优秀候选基因。CYP19a基因启动子中的变异也可能参与芳香化酶表达的调控，并影响将胆固醇代谢与性类固醇合成联系起来的调节机制。在本研究中，采用聚合酶链反应-单链构象多态性（PCR-SSCP）检测到9个单核苷酸多态性（SNP），即A-680G、G-672A、AGTAGT-649插入或缺失、T-623C、C-410A、T7-454A、T-402C、TTTCCAGACTGA-345插入或缺失以及G-297C。在50尾雌性牙鲆个体群体中，对CYP19a基因启动子内的9个SNP与4个繁殖性状[血清睾酮（T）、血清17β-雌二醇（E₂）、肝体指数（HSI）和性腺指数（GSI）]进行了关联分析。一个位点P3（TTTCCAGACTGA-345插入或缺失、G-297C）与雌性牙鲆的17β-雌二醇（E₂）水平显著相关（P < 0.05）。此外，基于9个SNP的一种双倍型与繁殖性状之间存在显著关联。双倍型D3对E₂水平的遗传效应显著高于其他双倍型（P < 0.05）。结果表明，这些变异对E₂水平的遗传效应可能有助于解释CYP19a基因在牙鲆繁殖内分泌学中的状态。
