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柞蚕传染性软腐病病毒是从感染吐白水软化病的柞蚕体内分离的一株小RNA病毒,属于软腐病病毒属(Iflavirus),含解旋酶结构域的2C蛋白是该病毒的功能蛋白质之一.以感染柞蚕软腐病病毒的柞蚕蛹cDNA为模板,PCR获得2C蛋白的编码基因,并利用Bac-to-Bac表达系统构建重组杆粒pFastBac-Dual-GFP-Hel 2C,在昆虫细胞Sf9中表达了该病毒的2C蛋白.对重组2C蛋白的三磷酸核苷水解酶(NTPase)活性和解旋酶活性进行检测的结果显示:重组2C蛋白具有NTPase活性,能够水解4种NTP,并且具有解旋酶活性,能够解旋3'端至5'端方向单链突出的双链DNA.初步推测2C蛋白在柞蚕传染性软腐病病毒复制中发挥水解三磷酸核苷和解旋DNA链的作用.“,”Antheraea pernyi iflavirus is a new small RNA virus isolated from A.pernyi larvae showing vomiting disease.2C protein,which contains the helicase domain,is one of its functional proteins.In this study,A.pernyi iflavirus cDNA was used as template to amplify the coding gene of 2C protein.Bac-to-Bac expression system was used to construct recombinant bacmid pFastBac-Dual-GFP-Hel 2C,which was used to express 2C protein in Sf9 insect cells.Enzymatic activity analyses on nucleotide triphosphotase (NTPase) and helicase displayed that the recombinant 2C protein has NTPase activity,being able to hydrolyze 4 kinds of NTPs.This protein also possesses a helix-destabilizing activity,which could disrupt DNA-DNA duplexes with 3'end single-stranded overhangs.It is preliminarily inferred that 2C protein plays roles in hydrolysis of nucleotide triphosphates and unwinding of DNA strand during replication of A.pernyi iflavirus.