利用RT-PCR方法从猪沙波病毒CH430株中克隆出非结构蛋白p70基因并测序，结果显示，p70基因全长1 995 nt，编码665个氨基酸，经同源性比对及遗传进化树分析表明，CH430株为基因Ⅲ型沙波病毒毒株。生物信息学分析显示该蛋白理论等电点(pI)为5.96，理论分子质量为72 876.6 u；其序列上共发现25个磷酸化位点，分别为Ser(6)、Thr(13)、Tyr(6)，而蛋白的磷酸化与信号传导有关，预测该蛋白为一重要的信号传导分子；无信号肽和跨膜区；该蛋白含有胰蛋白酶样丝氨酸蛋白酶和RdRp功能域；胰蛋白酶样丝氨酸蛋白酶功能域核心结构为1个由7个β折叠形成柱状结构和1个由1个α螺旋和7个β折叠扭曲平行形成1个不完全的桶状结构共同组成，RdRp功能域核心结构为1个具有3个子结构域空间结构，该结构与右手掌在形态上非常相似，而3个子结构域也被认为是手指、手掌和拇指。
The non-structural protein p70 gene of PoSaV CH430 strain was cloned by RT-PCR and then sequenced in our study.The results showed that the full length of p70 gene was 1 995 nt encoding a protein of 665 aa.Homology alignment and evolutionary tree showed that PoSaV CH430 strain belong to GⅢ.The bioinformatics analysis demonstrated that the isoelectric point and molecular weight of non-structural protein p70 were 5.96 and 72 876.6 u.The protein had no signal peptide and transmenbrane domain.There were 25 phosphorylation sites including 6 Sers, 13 Thrs and 6 Tyrs.Protein phosphorylation was concerned with signal transduction, so this protein may be a signaling molecule.There were Trypsin-like serine proteases and RdRp functional domain.Main structure of trypsin-like serine proteases functional domain was a column structure and an incomplete β-barrel.Main structure of RdRp functional domain was a fold whose organisation has been likened to the shape of a right hand with three subdomains termed fingers, palm and thumb.
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