过表达山羊ATF3抑制肌内前体脂肪细胞分化

Overexpression of ATF3 inhibits the differentiation of goat intramuscular preadipocytes

本研究旨在探究山羊转录激活因子3(activating transcription factor 3,ATF3)对肌内前体脂肪细胞分化的影响,并从分子水平阐明其可能作用途径。利用基因重组方法构建pEGFP-N1-ATF3过表达重组质粒,脂质体转染肌内前体脂肪细胞,通过油红O脂肪染色法从细胞形态学水平确定对分化的影响,利用实时荧光定量PCR(qRT-PCR)技术检测脂肪细胞分化标记基因相对表达水平,从分子水平确定对分化的影响。最终成功构建pEGFP-N1-ATF3过表达载体,转染山羊肌内前体脂肪细胞后发现脂滴积聚被抑制,qRT-PCR检测到脂肪细胞分化标志基因PPARγ、C/EBPα、SREBP1极显著下调(P<0.01),C/EBPβ、AP2显著下调(P<0.05),通过ALGGEN PROMO程序预测PPARγ、C/EBPα和AP2的启动子区域存在ATF3结合位点。研究表明,过表达山羊ATF3抑制肌内前体脂肪细胞脂滴积聚,这种作用通过下调PPARγ、C/EBPα和AP2来实现,研究结果为阐明山羊ATF3调控肌内前体脂肪细胞分化机制提供重要的基础数据。

The aim of this study was to investigate the effect of activating transcription factor 3(ATF3)on the differentiation of intramuscular preadipocytes in goat,and to elucidate its possible action pathway at the molecular level.In this study,the recombinant plasmid of goat pEGFP-N1-ATF3 was constructed,and the intramuscular preadipocytes were transfected with liposomes.The relative expression levels of adipocyte differentiation marker genes were detected by quantitative real-time PCR(qRT-PCR).After transfection of goat intramuscular preadipocytes with the goat pEGFP-N1-ATF3 overexpression vector,it was found that the accumulation of lipid droplets was inhibited,and the adipocyte differentiation markers PPARγ,C/EBPαand SREBP1 were extremely significantly down-regulated(P<0.01),while C/EBPβand AP2 were significantly down-regulated(P<0.05).The ATF3 binding sites were predicted to exist in the promoter regions of PPARγ,C/EBPαand AP2 by the ALGGEN PROMO program.The overexpression of goat ATF3 inhibits the accumulation of lipid droplets in intramuscular preadipocytes,and this effect may be achieved by down-regulating PPARγ,C/EBPαand AP2.These results may facilitate elucidation of the regulatory mechanism of ATF3 in regulating the differentiation of goat intramuscular preadipocytes.