不同乳脂率德宏奶水牛乳腺组织脂滴形成相关基因的表达研究

Expression of Genes Related to Lipid Droplet Formation in Mammary Tissue of Dehong Dairy Buffalo with Different Milk Fat Contents

本研究旨在探索脂滴形成相关基因嗜乳脂蛋白(BTN1A1)、黄嘌呤脱氢酶(XDH)、围脂滴蛋白1(PLIN1)和PLIN2在不同乳脂率德宏奶水牛乳腺组织中的表达差异。试验选取同一养殖小区的健康德宏奶水牛216头,采集乳样,用乳品分析仪测定乳脂率。根据乳脂率测定结果,分为低乳脂率组(L组,<7.0%)、中乳脂率组(M组,7.5%±0.5%)和高乳脂率组(H组,>8.0%),每组选取第2胎、年龄相近、处于泌乳中期的德宏奶水牛各3头,采集乳样,进行乳脂率测定;屠宰后采集乳腺组织,提取总RNA,利用实时荧光定量PCR技术检测脂滴形成相关基因的mRNA表达水平,并与乳脂率及脂肪酸含量进行相关性分析。试验结果显示,BTN1A1、XDH、PLIN1和PLIN2基因具有相同的表达趋势:H组>M组>L组;其中H组德宏奶水牛乳腺组织BTN1A1、XDH、PLIN1和PLIN2基因mRNA表达水平均极显著高于M组和L组(P<0.01);M组BTN1A1基因表达水平与L组差异不显著(P>0.05),但XDH、PLIN1和PLIN2基因mRNA表达水平均极显著高于L组(P<0.01)。相关性分析表明,BTN1A1、XDH、PLIN1和PLIN2基因表达水平均与乳脂率、总脂肪酸、长链脂肪酸及不饱和脂肪酸含量呈极显著正相关(P<0.01)。本研究结果表明,BTN1A1、XDH、PLIN1和PLIN2基因在乳腺组织的表达可能对德宏奶水牛的乳脂合成及分泌有显著促进作用,可为深入解析脂滴形成相关基因在泌乳过程中的调控机制提供参考。

The purpose of this study was to explore the expression differences of BTN1A1、XDH、PLIN1 and PLIN2 genes which were lipid droplet formation related genes in the mammary tissue of Dehong dairy buffalo with different milk fat contents.216 healthy Dehong dairy buffaloes with the same breeding community were selected in this experiment.Milk samples were collected,and milk fat contents were detected by milk composition analyzer.According to the determination result of milk fat contents,the experiments were divided into low milk fat content group(L group,<7.0%),medium milk fat content group(M group,7.5%±0.5%)and high milk fat content group(H group,>8.0%).Three Dehong dairy buffaloes with second fetuses,similar age and in the middle lactation stage were selected in each group.After slaughter,the breast tissue was collected and the total RNA was extracted.The mRNA expression levels of lipid droplet formation related genes in mammary tissue were detected by Real-time quantitative PCR,and the correlation between the lipid droplet formation related genes expression and milk fat contents,fatty acid contents were analyzed.The results showed that the same expression trend of BTN1A1,XDH,PLIN1 and PLIN2 genes were fallow as:group H>group M>group L.The mRNA expression levels of BTN1A1,XDH,PLIN1 and PLIN2 genes in the mammary tissue of Dehong dairy buffalo in group H were extremely significantly higher than those in group M and group L(P<0.01).The expression level of BTN1A1 gene was no significant difference between group M and group L(P>0.05),but the mRNA expression levels of XDH,PLIN1 and PLIN2 genes in group M were extremely significantly higher than those in group L(P<0.01).Correlation analysis showed that the expression levels of BTN1A1,XDH,PLIN1 and PLIN2 genes were significantly positively correlated with milk fat contents,total fatty acids,long chain fatty acids and unsaturated fatty acids contents(P<0.01).The results of this study indicated that the expression of BTN1A1,XDH,PLIN1 and PLIN2 in mammary tissue might have a positive effect on milk fat synthesis and secretion in Dehong dairy buffalo,which would provide a reference for further explanation of regulation mechanisms on lipid droplet formation related genes during lactation.