中国西门塔尔牛MC3R和MC4R基因组织表达谱及其在脂肪组织中表达水平与背膘厚度的相关性研究

The Tissues Profile of MC3R and MC4R and the Association of Their Expression in the Adipose with Backfat Thickness in Chinese Simmental Cattle

为探索调控肉牛脂肪沉积的关键基因表达规律,筛选影响肉牛肥育性状的候选基因,本研究采用137头18月龄肉用中国西门塔尔公牛,屠宰并采集组织样品,根据背膘厚度胴体测定值分成高、低2组,每组各选择15个个体,利用荧光实时定量技术对MC3R和MC4R基因在组织中的表达特征及其在不同个体脂肪组织中的表达水平进行分析。结果表明,MC3R和MC4R基因在睾丸、小肠、心脏、胰腺、淋巴、肾脏、脾脏、肝脏、肺脏、肌肉和脂肪组织中均有不同程度的表达,MC3R和MC4R基因在不同组之间的表达差异显著(P<0.05),且与背膘厚度呈显著相关(r=0.784,P<0.05;r=0.836,P<0.05)。结果说明MC3R和MC4R基因与肉牛背膘厚度有显著相关,是影响肉牛肥育性状的候选基因。

In order to explore the expression rule of key gene and screen the candidate gene affecting fat deposition,30 samples from 137 slaughtered 18 month Chinese simmental beef cattle were divided into thick（H） and thin（L） backfat groups,and the expression of MC3R and MC4R were analyzed in the adipose of different samples and other tissues.The result indicated that both the MC3R and MC4R expressed in the heart,liver,spleen,lung,kidney,muscle,adipose,thymus,small intestine,lymph and testis.The abundances of both the MC3R and MC4R mRNA in adipose were higher in L group than those in H group（P0.05）,and correlated with backfat thickness（r=0.784,P0.05;r=0.836,P0.05;respectively）.The results indicate that MC3R and MC4R had significant relationship with backfat thickness and might be a candidate gene for fattening in beef cattle.