黄羽肉鸡胰蛋白酶原基因的克隆及蛋白结构预测和功能分析

采用分子克隆技术克隆了黄羽肉鸡胰蛋白酶原(TRY)基因,并运用多种生物信息学软件对TRY蛋白质结构和功能进行了分析和预测,研究TRY在禽类消化过程中的作用.结果表明:黄羽肉鸡TRY基因的开放阅读框全长747 bp,由248个氨基酸残基组成,其中包含15个氨基酸的信号肽(MKFLVLVAFLGVAVA)和10个氨基酸的激活肽(FPISDEDDDK);该蛋白分子质量为26.1 ku,含有信号肽,不含有糖基化位点,有11个磷酸化位点;此外,该蛋白属于疏水性蛋白,但不存在跨膜区.氨基酸序列比对的结果表明:黄羽肉鸡TRY具有丝氨酸蛋白酶的保守结构特征,如含有催化三联体氨基酸(组氨酸-64、天冬氨酸-110和丝氨酸-203);具有构成6个二硫键所需的12个半胱氨酸残基等.序列一致性分析表明,黄羽肉鸡TRY与纯种鸡的同源性最高,达98.8%.

Molecular cloning,structure prediction and function analysis of trypsinogen in yellow broiler

To elucidate the function of trypsinogen ( TRY) in the process of digestion in poultry, TRY gene of yellow broiler was successfully cloned, and a series of bioinformatics software were used to analyze and predict the structure and function of TRY. Re-sults showed that full-length of open reading frame ( ORF) of TRY was 747 bp, which encoded 248 amino acids. TRY has a signal peptide of 15 amino acids ( MKFLVLVAFLGVAVA) and an activation peptide of 10 amino acids ( FPISDEDDDK) . The molecular weight of TRY was 26.1 ku, with 11 phosphorylation sites but no glycosylation site. TRY was hydrophobic without transmembrane domain. Alignment analysis based on the amino acid sequences revealed that TRY from yellow broiler was highly conservative, which included the catalytic triad ( His-64, Asp-110 and Ser-203) , with 12 cysteines forming 6 disulfide bonds. Homology analysis indi-cated that TRY from yellow broiler and purebred chicken had the highest homology at 98.8%.