绒山羊不同肌肉组织及肌内脂肪细胞的基因表达分析

Gene Expression Analysis on Different Muscles and Intramuscular Adipocytes in Cashmere Goat

试验旨在研究脂肪沉积关键基因在内蒙古白绒山羊的表达规律,以期深入分析绒山羊肌内脂肪沉积特征。利用实时荧光定量PCR技术检测PPARγ、FTO、Lipin、LPL、HSL、A-FABP和Perilipin 7个基因在绒山羊10个不同肌肉组织及肌内前体脂肪细胞分化的3个时期(早期(D3)、中期(D7)、末期(D11))、诱导分化关键时间点(24、48、72和96h)的变化,分别从组织和细胞角度对其进行分析,并研究其与肌内脂肪含量的关系。结果表明,FTO基因的表达水平高于其他基因;Lipin基因的表达量最低;LPL和HSL是脂肪合成和分解的关键酶类,其表达趋势大致相同,仅仅在腰大肌和斜方肌这两个部位的表达模式相反。A-FABP和Perilipin基因表达模式也较为特殊,整体表达量较低,前者仅仅在胸下矩肌中有较高表达,后者在股二头肌中有较高表达。从细胞水平分析发现Lipin、PPARγ、A-FABP和Perilipin的表达模式相似,随着前体脂肪细胞培养日龄的增加和甘油三酯的积聚,其表达量逐渐升高;Lipin基因在各个时间点的表达丰度极低;HSL基因的表达量随分化程度的升高而逐渐降低;Perilipin基因仅仅在诱导分化的后期有较高表达。相关性统计分析发现,PPARγ基因mRNA与肌内脂肪多呈负相关;而其他成脂基因HSL、LPL、FTO、Lipin、Perilipin、A-FABP mRNA与肌内脂肪含量多呈正相关。因此,脂肪沉积关键基因的表达具有特异性,总体上看基因表达量为FTO>PPARγ>LPL>HSL>A-FABP>Perilipin>Lipin,该结果为进一步研究脂肪沉积机制及优化山羊肉品质奠定基础。

The objective of this study was to discover the expression of key genes for fatty deposition in Inner Mongolia cashmere goat,so that deeply analysize the change features of intramuscular fat deposition.Real-time PCR was used to detect the expression pattern of seven different genes（PPARγ,FTO,Lipin,LPL,HSL,A-FABP and Perilipin）in ten different muscle tissues,and in intramuscular adipocyte for three periods as early（D3）,middle（D7）,and end（D11）,as well as the changes in key points of induced differentiation time（24,48,72 and 96h）.The correlation between the seven genes and the intramuscular fat content was researched from the prospective of analyzing the tissues and cells.The results showed that FTOgene mRNA had a higher expression in different tissues than that of other genes.While the Lipin gene mRNA expressionwas the lowest than others,LPL and HSL were the key enzymes in the fat synthesis and splitting,the expression trends of which were basically similar,they only showed the opposite expression pattern in the psoas major muscle,and trapezius A-FABPand Perilipingene expression patterns were more special,the overall expression level was lower,the former＇s expression level was higher in next moment chest muscle than other tissues,while the latter＇s expression level was higher in biceps femoris muscle than other tissues.Analyzing from the cell level,the expression patterns of Lipin,PPARγ,A-FABP and Perilipin were similar,with the increase of adipocytes cultivating day age and the triglyceride accumulation,the corresponding expression level increased gradually;The expression abundance of Lipingene in each time point was extremely low;The expression level of HSLgene reduced gradually as the differentiation degree increases;The expression level of Perilipin gene was higher only in the late period of induction and differentiation.Through statistical analysis of the correlation,the PPARγgene mRNA of cashmere goat formed negative correlation with intramuscular fat;While other adipogenic genes like HSL,LPL,FTO,Lipin,Perilipinand A-FABP mRNA formed positive correlation with intramuscular fat content.Therefore,the key gene expression of fat deposition had the specificity,generally,the amount of gene expression by quantitative analysis was FTOPPARγLPLHSLA-FABPPerilipinLipin,such results lay foundation for further researching the fat deposition mechanism and improving the quality of cashmere goat.