早胜牛CD36基因第9外显子多态性及不同组织mRNA表达分析

Analysis of Polymorphism of CD36 Gene Exon 9 and mRNA Expression in Different Tissues of Zaosheng Cattle

为探讨早胜牛脂肪酸转位酶(CD36)基因第9外显子多态性与肉用性状的相关性,试验以早胜牛为研究对象,用PCR-SSCP技术对早胜牛CD36基因第9外显子进行遗传多态性检测,分析SNP位点与早胜牛肉用性能的关联性。同时用实时荧光定量PCR法分析CD36基因在早胜牛不同组织的mRNA表达差异性及其与肌内脂肪含量的相关性。结果显示:CD36基因第9外显子在T83125C位点存在一个SNP,具有TT和TC 2种基因型,TC型的宰前活重、胴体重、肌内脂肪都显著高于TT型(P<0.05);CD36基因在4个组织中均有表达,表达水平由高到低依次为心脏、腿肌、背最长肌和肝脏,心脏的mRNA表达量显著高于肝脏(P<0.05),背最长肌中CD36基因mRNA表达量与IMF含量呈显著正相关(P<0.05),相关系数为0.855。说明CD36基因T83125C位点可作为早胜牛肉用性状分子标记位点,CD36基因可作为早胜牛肌内脂肪沉积和肉用性状的候选基因。

To research the correlation between the polymorphism of CD36 gene exon 9 and meat traits and its expression characteristics in different tissues of Zaosheng cattle,the genetic polymorphism of CD36 gene exon 9 of Zaosheng cattle was detected by PCR-SSCP.The correlation between SNP loci and the characteristics of Zaosheng meat was analyzed,at the same time,the mRNA expression difference of CD36 gene in different tissues and its correlation with intramuscle fat content of Zaosheng cattle were analyzed by real-time fluorescence quantitative PCR.The results showed that there is an SNP in exon 9 of CD36 gene at loci T83125C,which contains TT and TC genotypes.The live weight,carcass weight and intramuscular fat of TC genotype are significantly higher than that of TT genotype(P<0.05).The mRNA expression of CD36 gene is expressed in all 4 tissues,and the expression level from high to low is heart,leg muscle,longissimus dorsi muscle and liver.The mRNA expression level in heart is significantly higher than that in liver(P<0.05).The mRNA expression level of CD36 gene in longissimus dorsi muscle is significantly positively correlated with IMF content(P<0.05),and the correlation coefficient is 0.855.These results indicate that the T83125C locus of CD36 gene could be used as a molecular marker site for meat traits in Zaosheng cattle,and CD36 gene could be used as a candidate gene for intramuscularfat deposition and meat traits in Zaosheng cattle.