鸭极低密度脂蛋白受体和载脂蛋白E受体2在肌肉组织中的发育性表达模式研究

Developmental Expression Patterns of VLDLRand ApoER2 Genes in Duck Muscles

为探索极低密度脂蛋白受体（verylowdensitylipoproteinreceptor，VLDLR）和载脂蛋白E受体2（apolipoproteinEreceptor2，ApoER2）在鸭肌内脂肪性状发育中的作用机制，本研究应用实时荧光定量PCR检测了VLDLR和ApoER2基因在1-8周龄北京鸭胸肌、腿肌、心肌中的表达丰度，分析其在早期生长阶段的发育性变化。结果显示VLDLR和ApoER2在鸭不同肌肉中的表达具有组织特异性。VLDLR基因mRNA丰度在3种肌肉组织中变化较大，且明显呈现上升下降（胸肌）、下降-上升-下降上升（腿肌）及下降-上升下降（心肌）3种模式的变化；ApoER2基因mRNA表达量在胸肌第3周龄时达最高（P〈0．01），在腿肌组织中前6周保持相对较低水平，在后2周迅速上升，且显著高于其余各周（P〈0．01），而在心肌组织中呈上升-下降趋势，且在前2周表达量显著高于其余各周（P〈0．01）。同周龄VLDLR和ApoER2基因mRNA的表达量在不同部位肌肉中表现出明显差异。以上结果说明，VLDLR和ApoER2基因在鸭肌内脂肪性状形成中起到了重要作用，且存在着时空特异性。

To identify the possible role of very low density lipoprotein receptor （VLDLR） and apolipoprotein E receptor 2 （ApoER2） genes in duck muscles, the developmental changes of VLDLR and ApoER2 mRNA level in breast muscle, leg mus- cle and cardiac muscle during duck early growth stages were investigated using Real-time fluorescent quantity PCR. The results showed that VLDLR and ApoER2 mRNA expression level was different in different muscle tissues from 1 to 8 week in duck and had tissue-dependent. Three expression patterns of VLDLR mRNA during growth were found： Fluctuating expression as up-down （breast muscle）, as down-up down-up （leg muscle） and as down up down （cardiac muscle）. For ApoER2 mRNA ex- pression level, in breast muscle, the mRNA expression level was the highest （P〈0.01） in 3 week old duck. In leg muscle, the mRNA expression level kept a low level in the first 6 weeks, then had a significant increase in 7 and 8 weeks, which was signif- icantly higher than that of other weeks （P〈0.01）. During the cardiac tissue development, the mRNA expression level presen- ted as up-down with growing, and had a higher expression level in the first 2 weeks （P〈0.01）. In the same week VLDLR and ApoER2 mRNA expression level had tissue-dependent in muscles of three different sites in duck. Our results indicated that VLDLR and ApoER2 genes could play an important role in intramuscular fat accumulation with spatial and temporal specificity during duck early growth stages.