藏绵羊PPARα基因遗传变异特征及组织表达分析

Genetic Variation Characteristics and Tissue Expression Analysis of PPARα Gene in Tibetan Sheep

PPARα(Peroxisome proliferator activated receptorsα)基因参与调控线粒体脂肪酸β氧化,在能量代谢中具有重要作用,是动物高原低氧适应的主要候选基因之一。本研究采用PCR-SSCP和测序方法检测2个品种(藏绵羊,湖羊) PPARα基因P1区核苷酸变异及遗传特征。采用实时荧光定量PCR (quantitative real-time PCR, qRT-PCR)检测藏羊与湖羊心脏、肝脏、脾脏、肺脏、肾脏、骨骼肌6个组织的相对表达量。检测表明:在扩增区域发现2个SNPs (c.515-22A>G, c.515-10C>T)对应的等位基因A、B。基因频率在2个群体间具有统计学意义(p<0.01),藏绵羊的优势基因型为AB,湖羊优势基因型为AA。推测AB基因型个体可能更有利于藏绵羊适应高原低氧环境,可作为藏绵羊低氧适应选育的分子标记。PPARα基因在2个绵羊的6个组织中均有不同程度的表达且具有品种间差异性。PPARα基因在藏绵羊心脏的表达量极显著的低于其余5个组织(p<0.01),而2个品种间,藏绵羊各组织的表达量均低于湖羊,其中在心脏、肝脏、肺脏3个组织表达量极显著的低于湖羊(p<0.01)。本研究可丰富绵羊基因组学内容,为藏绵羊低氧适应研究提供基础数据。

PPARα(Peroxisome proliferator activated receptorsα)gene is involved in the regulation of mitochondrial fatty acidβoxidation,which plays an important role in energy metabolism.It is one of the major candidate genes for animals adapting to the hypoxic environment of plateau.In the study,using PCR-SSCP and sequencing methods,nucleotide variation and genetic characteristics in P1 region of PPARαin two sheep breeds(Tibetan sheep,Hu sheep)were detected.The relative expression levels of six tissues included heart,liver,spleen,lung,kidney,skeletal muscle of Tibetan sheep and Hu sheep were detected by qRT-PCR.The results indicated that two corresponding alleles A and B of SNPs(c.515-22 A>G,c.515-10 C>T)were found in the amplification regions.Gene frequencies between the two groups had statistical significance(p<0.01),the advantage genotype of Tibetan sheep was AB,and the advantage genotype of Hu sheep was AA.It was speculated that AB genotype individuals might be more beneficial to hypobaric hypoxia adaptation,which could be used as the molecular marker for the breeding of hypoxia adaptation in Tibetan sheep.PPARαgene was expressed differently in six tissues of two sheep and had differences in varieties.The expression of PPARαgene in heart of Tibetan sheep was significantly lower than that of other five tissues(p<0.01).Among the two varieties,the expression of tissues of the Tibetan sheep was lower than those of the Hu sheep,and the expression in heart,liver and lung was significantly lower than those of the Hu sheep(p<0.01).This study could enrich the contents of sheep genomics and provide basic data for the study of hypoxia adaptation of Tibetan sheep.