二花脸猪Smad4基因的克隆与卵巢组织mRNA的表达水平

目的]了解二花脸猪Smad4(common-mediator Sma4)基因的序列特征和组织表达特征,分析二花脸猪与商品猪卵巢组织中Smad4基因mRNA表达水平的差异.方法]采用克隆测序技术获得二花脸猪Smad4基因cDNA序列,利用生物信息学方法分析二花脸猪Smad4基因的序列特征和蛋白的理化性质、高级结构,RT-PCR检测其组织表达特征,并采用real-time PCR技术检测二花脸猪与商品猪卵巢组织中Smad4基因mRNA的表达水平.结果]二花脸猪Smad4基因编码区序列全长1 659 bp,编码一个含有5 52个氨基酸残基的蛋白质,氨基酸序列与其它哺乳动物的同源性均在98％以上；二花脸猪Smad4也包括3个典型的结构域(MH1、SAD和MH2).二花脸猪Smad4基因在所检测的组织中均有表达,且卵巢组织中mRNA的表达水平极显著高于商品猪(P＜0.01).结论]二花脸猪Smad4基因可能拥有其它哺乳动物Smad4基因相同的功能及其可能与猪高繁殖力间有一定相关.

Cloning and mRNA Expression of Smad4 Gene in Ovaries of Erhualian Pig

【Objective】To investigate The sequence features and tissue distribution patterns of Smad4 gene in Erhualian pigs were investigated, and the Smad4 mRNA expression differences in ovarian tissue between Erhualian and commercial cross pigs were analyzed. 【Method】The cDNA sequence of Smad4 gene was obtained by cloning and sequencing techniques in Erhualian pigs, the gene sequence characteristics, physical and chemical properties and the 3D structure of Smad4 protein were analyzed by using bioinformatics methods. The tissue distribution patterns of Smad4 gene were detected by RT-PCR, and then the mRNA expression levels were detected in ovarian tissue of Erhualian and commercial cross pigs by real-time PCR.【Result】The full length of Smad4 gene coding sequence was 1 659 bp in Erhualian pigs, encoding for a protein with 552 amino acid residues. The coding amino acid sequence was highly conservative with other mammals (more than 98% identity). Same as other mammals, Smad4 protein in Erhualian pigs also had three typical structural domains (MH1, SAD and MH2). RT-PCR assays revealed that Smad4 gene of Erhualian pigs widely expressed in all tissues. In addition, Smad4 mRNA levels in Erhualian pig ovary was significantly higher than that in commercial pigs (P＜0.01). 【Conclusion】 The Smad4 gene in Erhualian pigs may be own the same function as other mammals and exert probably associated with the pig prolificacy.