Ephrin B2在猪不同组织中的表达谱和基因多态性与产仔数的关联分析

Expression profile of Ephrin B2in different tissues of swine and association of gene polymorphism and litter size

为研究促红细胞生成素产生肝细胞配体B2(Ephrin B2)对母猪繁殖性能的影响,探讨其作为影响猪产仔数主效候选基因的可能性,采用Real-time PCR方法检测了Ephrin B2在猪肝脏、肾脏、膀胱、卵巢、输卵管、子宫体和子宫内膜组织中的表达谱;然后用PCR-SSCP方法在长白猪、大白猪、杜洛克猪、二花脸猪、苏钟猪、梅山猪和金华猪7个品种共717头母猪中检测了Ephrin B2基因的多态性,并与猪产仔数进行了关联分析。结果表明,各组织中Ephrin B2的mRNA表达量不同,按大小排序依次为:子宫内膜>子宫体>膀胱>肾脏>卵巢>输卵管>肝脏,除肾脏与膀胱间的表达量差异不显著外,其他任意组织两两间的Ephrin B2表达量均差异显著(P<0.05)或极显著(P<0.01)。Ephrin B2第4外显子上检测到1个SNP突变,命名为EphrinB2_4,为T→C突变,C为优势等位基因,长白、大白和杜洛克猪中基因型CC与TT间在产仔数上均差异显著(P<0.05);在长白、大白、杜洛克、梅山和金华猪种中的等位基因频率为C>T。以上结果表明,EphrinB2_4位点的CC基因型可作为在猪高产仔数性状的标记基因型,进行标记辅助选择育种。

In order to explore the feasibility of erythropoietin-producing hepatocellular ligand B2（Ephrin B2） as a major candidate gene affecting litter size in pigs,expression of Ephrin B2 profile was studied in tissues of liver,kidney,bladder,ovary,oviduct,uterus and endometrial of pigs by real-time PCR.Furthermore,Ephrin B2 gene DNA polymorphism had been studied in 717 sows from 7 breeds,including Landrace,Yorkshire,Duroc,Erhualian,Suzhong,Meishan and Jinhua.The association of gene polymorphism and reproductive traits was also assessed.The results showed that Ephrin B2 mRNA expression level was different in various tissues,sorted as bladder kidney ovary oviduct liver.Except for kidney and bladder,other tissues showed significant difference in the expression level of Ephrin B2（P0.05）.A SNP（single nucleotide polymorphism） was found in exon 4 of Ephrin B2,named EphrinB2_4,being T→C mutation.C was a predominant allele.Genotype TT was significantly different from CC in litter size of Landrace,Yorkshire and Duroc breeds.Allele frequency of C was higher than that of T in Landrace,Yorkshire,Duroc,Meishan and Jinhua breeds.It indicated that genotype CC at EphrinB2_4 could be used as a molecular marker of high litter size,and applied in marker-assisted selection of swine.