罗非鱼脂肪肝病的脂肪代谢分子调控机制

This research pertains to the popular status quo that of fatty liver disease during the breeding process of Tilapia. It aims at adjustment of nutrition to modify the expression of genes, in order to affect the fat metabolism in Tilapia's liver and consequently prevent its fatty liver disease. In this research application of gene chip technology based on molecular biology was used for Biotin fluorescent labeling the cDNA session technology. Then test and analyze the genetic maps of healthy Tilapia fish and those disordered with fatty liver disease while draw comparisons between the healthy and disordered one. According to the composition of fatty acid in liver, channels of lipid oxidation and transmission, clone and sequence homology analysis were conducted respectively on several genes of enzymes of Tilapia-fatty acid synthase(FAS), lipoprotein lipase(LPL), lipoprotein lipase(HL), enoyl coenzyme A hydratase short chain 1(ECHS1), carnitine acyltransferase(CAT). The genetic compositions and functions were examined based on the results while adopting the real-time PCR assay for studies on the genetic expressions of FAS, LPL, HL, ECHS1, CAT during the pathological process of fatty liver disease.

本项目针对罗非鱼养殖过程中普遍存在的脂肪肝病现状，应用分子生物学的基因芯片技术的Biotin荧光标记cDNA片段，分析和检测正常和脂肪肝病变罗非鱼肝脏基因表达图谱，并对标准图谱和病变图谱进行比较分析；根据肝脏脂肪酸合成、脂肪氧化和脂肪转运途径，对罗非鱼肝脏脂肪酸合成酶（FAS）基因、脂蛋白脂酶(LPL)基因、肝酯酶（HL）基因、烯酰辅酶A水合酶短链1（ECHS1）基因、肉碱酰基转移酶（CAT）基因克隆，进行序列同源性比较，同时分析基因结构和功能，并采用实时荧光定量PCR技术研究脂肪肝病变过程中FAS、LPL、HL、ECHS1、CAT基因的表达。以期通过营养因子的改变调节相关基因的表达，进而影响罗非鱼肝脏的脂肪代谢，最终控制罗非鱼脂肪肝的发生。

本项目针对罗非鱼养殖过程中普遍存在的脂肪肝病现状，研究了吉富罗非鱼脂肪肝病变过程的生长性能、生理机能的变化特征。采用RT-PCR和RACE法对罗非鱼肝脏脂肪、；酸合成酶（FAS）基因、脂蛋白脂酶（LPL）基因、肝酯酶（HL）基因、烯酰辅酶A水合酶短链1（ECHS1）基因、肉碱酰基转移酶（CAT）基因克隆，首次得到以上基因的cDNA全长，同时分析基因结构和功能，并进行序列同源性比较。采用实时荧光定量PCR技术，研究了高脂饲料、高摄食率、不同胆碱及肉胆碱水平条件下的FAS, LPL,HL,ECHS1,CAT基因的表达，探究了罗非鱼脂肪肝病变过程中，这些基因在肝脏脂肪酸合成、脂肪氧化和脂肪转运途径中的作用机制。通过对罗非鱼病变脂肪肝转录组高通量测序的研究，构建了转录组测序文库，初步筛选出与病变脂肪肝脂质代谢密切相关的基因。项目研究成果为进一步寻找新的功能基因及诊断治疗罗非鱼脂肪肝病提供了重要的理论依据。