茶尺蠖核型多角体病毒多角体蛋白基因核苷酸序列及其在Baculoviridae中的地位(英文)

Nucleotide Sequence of the Polyhedrin Gene of Ectropis obliqua Single Enveloped Nucleopolyhedrovirus and the Placement of the Virus in Baculoviridae *

茶尺蠖核型多角体病毒（ＥｏＳＮＰＶ）基因组的ｐｏｌｈ和ｅｇｔ基因区约１４．２ｋｂ的酶切图谱被构建．ｅｇｔ基因位于ｐｏｌｈ基因上游约４．８ｋｂ处，但转录方向与ｐｏｌｈ基因相反．ＥｃｏＲⅤ－Ｌ片段ｐｏｌｈ基因及其旁侧的１１２５核苷酸序列被测定．ｐｏｌｈ基因编码区长７３８核苷酸，可编码２４６氨基酸的多肽．起始密码子ＡＴＧ上游是一个富含ＡＴ（ＡＴ占７１．２％）的启动子区，在－５２核苷酸处有杆状病毒晚期基因启动子转录起始基序ＡＴＡＡＧ．在终止密码子下游２０８核苷酸有一个ｐｏｌｙ（Ａ）信号，ＡＡＴＡＡＡ．但ＥｏＳＮＰＶｐｏｌｈ基因起始密码子ＡＴＧ相邻核苷酸序列为ＧＴＡＡＴＧＴ，其－３是个Ｇ，这与已知的１６种其它杆状病毒ｐｏｌｈ基因－３位置均是Ａ不相同．在分析了ＥｏＳＮＰＶ和ＨａＳＮＰＶ多角体蛋白基因核苷酸序列的基础上，通过ＭＡＬＩＧＮ程序，比较了目前已发表的２６种杆状病毒包涵体蛋白的序列，ＥｏＳＮＰＶ与黄杉毒蛾核型多角体病毒（ＯｐＳＮＰＶ）的同源性为最高，核苷酸序列的同源性为８３．０％，氨基酸序列达９４．７％；与其它２０种鳞翅目ＮＰＶ的同源性也很高，核苷酸序列同源性为７２．６％～８１．９％，氨基酸序列为８３．７％～９３?

A restriction endonuclease map was constructed for the 14 2 kb polyhedrin gene region of Ectropis obliqua single enveloped nucleopolyhedrovirus (EoSNPV) genome.The ecdysteroid UDP glucosyl transferase ( egt ) gene was localized 4 8 kb upstream of the polyhedrin gene and transcribed in the opposite direction.A portion of the Eco RⅤ L fragment containing the polyhedrin gene was sequenced.An open reading frame of 738 nucleotides encoding a putative 246 amino acid polypeptide representing the polyhedrin gene was determined.A conserved ATAAG motif,associated with transcriptional start sites in other polyhedrin genes,was identified 51 nucleotides upstream of the EoSNPV polyhedrin gene.a putative polyadenylation signal,AATAAA,was found 208 nucleotides downstream of the termination codon.The sequence surrounding the start condon ATG in the polyhedrin gene was GTAATGT,with G at position 3 instead of A as in other NPV's polyhedrin genes.Phylogenetic analysis of the polyhedrin gene shows that EoSNPV is a member of the previously described lepidopteran NPV group Ⅱ and that it is most closely related to the polyhedrin gene of Orgyia pseudotsugata SNPV.