高脂对银鲳脂肪酸跨膜转运蛋白CD36膜转位的调控作用及其机制研究

High-fat diets can improve the efficiency of fishmeal in farmed fish, but it also increases excessive lipid deposition. Thus, understanding the mechanisms of high-fat diets on lipid deposition is important for the use of high-fat diets. CD36 is a principal fatty acid transporter. After being synthesized, it must be transferred from cytoplasm to the plasma membrane and then mediate the transport of fatty acids across the plasma membrane. Increased translocation of CD36 plays a pivotal role in lipid deposition. And the translocation of CD36 is mainly controlled by the AKT/AS160 pathway. The hypothesis of the project is that high-fat diets could regulate translocation of CD36, and the AKT/AS160 pathway is involved in this process in fish. To test this hypothesis, we use silvery pomfret as model animal. We will investigate the function and mechanism of high-fat diets on the translocation of CD36 in vivo and in vitro with immunofluorescence staining and gene silencing techniques. The studies will provide some basic information about the molecular mechanism of high-fat diets induced-lipid deposition in fish.

高脂饲料能提高养殖鱼类对鱼粉的利用效率，但其应用也导致了鱼体脂肪过度沉积。因此，阐明高脂引起鱼类脂肪过度沉积的机制，对于高脂的广泛应用将具有重要的指导意义。CD36是最主要的脂肪酸跨膜转运蛋白，其合成后必须从细胞质转位到细胞膜才能介导脂肪酸进入细胞内，CD36膜转位增加在动物脂肪过度沉积中起着重要作用；而AKT/AS160是调控动物CD36膜转位的主要信号通路之一。本项目的假设是，高脂能调控鱼类CD36膜转位，AKT/AS160信号通路介导了该过程。本项目将以银鲳为研究对象，利用在体和离体研究模型，结合免疫染色、基因沉默等技术探索高脂对银鲳CD36膜转位的调控作用及其作用机制。本项目的研究成果将为深入研究高脂引起鱼类脂肪过度沉积的分子机制提供基础资料。

高脂饲料能提高养殖鱼类对鱼粉的利用效率，但其应用也导致了鱼体脂肪过度沉积。因此，阐明高脂引起鱼类脂肪过度沉积的机制，对于高脂的广泛应用将具有重要的指导意义。CD36是最主要的脂肪酸跨膜转运蛋白，在动物脂肪过度沉积中起着重要作用。本项目围绕CD36在银鲳脂肪过度沉积中的作用开展相关研究。首先，克隆了银鲳CD36，分析了其分子特征和表达规律，制备了CD36抗体，发现了转录因子PPARγ对CD36的转录调控作用；建立了银鲳肌肉原代细胞和肠细胞系高脂离体研究模型；利用在体和离体研究，阐明了高脂对银鲳CD36表达和脂肪沉积的影响；发现高脂调控银鲳CD36表达和脂肪沉积与热激蛋白GRP78和HSP70有关，初步揭示了CD36诱导银鲳脂肪过度沉积的机制。本项目的研究成果显示CD36在高脂导致银鲳脂肪沉积中起着重要作用，为深入研究高脂引起鱼类脂肪过度沉积的分子机制提供基础资料，也为开发调控鱼类脂代谢的饲料/添加剂提供了靶点和理论基础。