奶山羊SERPINA14基因克隆、生物信息学及组织差异表达分析

Cloning,Bioinformatics and Tissue Differential Expression Analysis of SERPINA14 Gene in Dairy Goats

SERPINA14(serpin peptidase inhibitor,clade A(alpha-1 antiproteinase,antitrypsin),member 14)是丝氨酸蛋白酶抑制剂(serine protease inhibitor,SERPIN)家族的重要成员,在蛋白质合成和代谢调控上具有重要作用,且表达蛋白质功能因物种而异。该研究旨在克隆西农萨能奶山羊SERPINA14基因的CDS区,进行生物信息学分析并利用qPCR技术检测其在各组织间及不同泌乳时期乳腺组织mRNA表达水平差异。结果表明,西农萨能奶山羊SERPINA14基因CDS区全长1311 bp,蛋白分子量为49.89 ku,由436个氨基酸组成,等电点大小为9.25,是一种稳定的碱性蛋白质;SERPINA14总平均亲水性-0.113,共有30个磷酸化位点,存在信号肽,有两段跨膜螺旋蛋白且具有SERPIN结构域,为跨膜亲水蛋白;同源性分析显示西农萨能奶山羊SERPINA14的核苷酸序列与山羊(Capra hircus)、绵羊(Ovis aries)、牛(Bos taurus)的同源性分别为100.00%、98.55%、90.08%,与山羊亲缘关系最近,其次是绵羊;不同组织表达分析显示在肾脏组织中表达量最高(P<0.01),其次是乳腺,在小肠中表达量最低;不同泌乳时期乳腺组织表达分析显示在干奶期表达量最高(P<0.01),其次是泌乳盛期,在泌乳前期表达最低。研究结果揭示SERPINA14基因可能参与奶山羊乳蛋白的合成代谢;为后续研究SERPINA14基因调控乳蛋白合成与代谢的机制奠定基础,为实现山羊奶品质的改良提供理论指导。

SERPINA14(serpin peptidase inhibitor,clade A(alpha-1 antiproteinase,antitrypsin),member 14),a member of the serine protease inhibitor(SERPIN)family,plays an important role in the regulation of protein synthesis and metabolism,and the function of expressed protein varies with species.The aim of this study was to clone the CDS region of SERPINA14 gene of Xinong Saanen dairy goats for bioinformatics analysis,and to detect the differences in mRNA expression levels of SERPINA14 gene among different tissues and mammary gland tissues of does during different lactation stages by Real-time quantitative PCR.The results showed that the CDS region of SERPINA14 gene is 1311 bp in length,encoding 436 amino acids.The molecular weight of the protein is 49.89 ku,and the isoelectric point is 9.25.It is a stable basic protein.The total average hydrophilicity of SERPINA14 is-0.113,there are 30 phosphorylation sites,signal peptides and two transmembrane helical proteins and there is a SERPIN domain,which indicates that it is a transmembrane hydrophilic protein.Homology alignment analysis showed that the nucleotide sequence of SERPINA14 gene of Xinong Saanen dairy goats with Capra hircus,Ovis aries and Bos taurus are 100.00%,98.55%and 90.08%,respectively.The goat(Capra hircus)is the closest species with Xinong Saanen dairy goats and then sheep(Ovis aries).Expression analysis of different tissues showed that the highest expression level was found in renal tissues(P<0.01),followed by the mammary gland,and the lowest expression was found in the small intestine.Expression analysis of mammary gland tissue at different lactation stages showed the highest expression level was found in dry lactation(P<0.01),followed by the peak stage,and the lowest expression was found in the early stage.These results suggest that SERPINA14 gene may be involved in milk protein synthesis and metabolism.This study lays a foundation for further study on the mechanism of SERPINA14 gene regulating milk protein synthesis and metabolism,and provides theoretical guidance for the improvement of goat milk quality.