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对棉铃虫单核衣壳核多角体病毒 (Helicoverpaarmigerasingle -nucleocapsidnucleopolyhedrovirus,HaSNPV)基因组中EcoRI N片段进行序列分析 ,获得了完整的解螺旋酶基因 (hel) ,其开放阅读框大小为 376 2bp ,编码一个分子量为 14 6kD的蛋白质。在hel起始密码子ATG上游 5 0位有强晚期启动子转录起始信号ATAAG ,在 112位和 189位存在两个TATAbox ,但未发现早期转录信号CAGT。其在终止密码子下游第 12位有一PolyA终止信号AATAAA。在其它真核或原核解螺旋酶中存在的 7个保守基元 (I、Ia、II、III、Ⅳ、Ⅴ、Ⅵ) ,只有 5个 (I、Ia、II、III、Ⅳ)在杆状病毒中保守同源性比较发现 ,HaSNPV解螺旋酶的氨基酸序列与甜菜夜蛾核多角体病毒 (SpodopteraexigueMNPV ,SeMNPV)的解螺旋酶具有最高的同源性 (6 6 % ) ,与Xestiac nigrum颗粒体病毒 (XcGV)解螺旋酶的同源性最低 (43% )。HaSNPV解螺旋酶基因是第一个报道的单粒包埋核多角体病毒的解螺旋酶基因
Sequence analysis of the EcoRI N fragment in the genome of Helicoverpa armigera genome single nucleocapsid nucleopolyhedrovirus (HaSNPV) resulted in the complete helicase gene (hel) with an open reading frame size of 376 2bp encoding a The molecular weight of 14 6kD protein. There is a strong late promoter transcription start signal ATAAG at helper start codon ATG 50 and two TATAbox at 112 and 189 but no early transcription signal CAGT was found. It has a PolyA termination signal AATAAA at position 12 downstream of the stop codon. Of the seven conserved motifs (I, Ia, II, III, IV, V, VI) present in other eukaryotic or prokaryotic helicases, only five (I, Ia, II, III, The amino acid sequence of HaSNPV helicase showed the highest homology (66%) with the helicase of Spodoptera exigua MNPV (SeMNPV), which was similar to the Xestiac nigrum granule Virus (XcGV) helicase has the lowest homology (43%). The HaSNPV helicase gene is the first reported single-core-contained nuclear polyhedrosis virus helicase gene