PDF(Pubmed)
Abstract：
To enhance our understanding of teleost reproductive physiology, we identified six Sichuan bream (Sinibrama taeniatus) vitellogenin genes (vtg1-6) and characterized their sequence structures. We categorized them into type Ⅰ (vtg1,4,5 and 6), type Ⅱ (vtg2) and type Ⅲ (vtg3) based on differences in their subdomain structure. The promoter sequence of vtgs has multiple estrogen response elements, and their abundance appears to correlate with the responsiveness of vtg gene expression to estrogen. Gene expression analyses revealed that the vitellogenesis of Sichuan bream involves both heterosynthesis and autosynthesis pathways, with the dominant pathway originating from the liver. The drug treatment experiments revealed that 17β-estradiol (E2) tightly regulated the level of vtg mRNA in the liver. Feeding fish with a diet containing 100 μg/g E2 for three weeks significantly induced vtg gene expression and ovarian development, leading to an earlier onset of vitellogenesis. Additionally, it was observed that the initiation of vtg transcription required E2 binding to its receptor, a process primarily mediated by estrogen receptor alpha in Sichuan bream. The findings of this study provide novel insights into the molecular information of the vitellogenin gene family in teleosts, thereby contributing to the regulation of gonadal development in farmed fish.
摘要：
为了提高我们对硬骨鱼生殖生理学的认识，我们鉴定了六个四川bream（Sinibramataeniatus）卵黄蛋白原基因（vtg1-6），并表征了它们的序列结构。我们将它们分为Ⅰ型(vtg1、4、5和6)，Ⅱ型(vtg2)和Ⅲ型(vtg3)基于其亚结构域结构的差异。vtgs的启动子序列具有多个雌激素反应元件，它们的丰度似乎与vtg基因表达对雌激素的反应性相关。基因表达分析表明，川鱼卵黄发生涉及异合成和自合成途径。主要途径来源于肝脏。药物治疗实验表明，17β-雌二醇（E2）紧密调节肝脏中vtgmRNA的水平。用含有100μg/gE2的饮食喂养鱼三周显着诱导vtg基因表达和卵巢发育，导致卵黄发生更早。此外,观察到vtg转录的启动需要E2与其受体结合，这一过程主要由川鱼的雌激素受体α介导。这项研究的发现为硬骨鱼卵黄蛋白原基因家族的分子信息提供了新的见解，从而有助于调节养殖鱼类的性腺发育。
