棉铃虫核型多角体病毒p40基因序列分析

Sequence Analysis of the Helicoverpa armigera Nuclear Polyhedrosis Virus p40 Gene

克隆了棉铃虫 (Helicoverpaarmigera)单粒包埋型核型多角体病毒 (HaSNPV)基因组HindⅢ H、J片段 ,其长度分别为 10kb和 6 .7kb。通过对克隆片段末端测序 ,得到HaSNPVp40基因全序列。p40基因编码区全长 96 6bp ,预计可编码 36 .kD的多肽。HaSNPVp40基因核苷酸序列与HzSNPVp40基因有 98%的相同性。这两种基因与BmNPVp40(GenBank -L33180 )和AcMNPVgp41(GenBank -L2 2 85 8)的氨基酸序列相似性 43%左右 ,但四种蛋白对应于HzSNPVp40、HaSNPVp40的 2 8～ 2 77氨基酸区域 ,同源性高达 6 2 % ,并且存在一个保守的亲水性结构域。进一步将在基因组中相邻的HindⅢ -H、J两片段用BamHⅠ、EcoRⅠ、HindⅢ、PstⅠ四种限制性内切酶进行了分析。

The Hind Ⅲ-H?J fragments of Helicoverpa armigera single nucleocapsid nucleopolyhedrovirus (HaSNPV) qenome were cloned. By sequencing the terminus of the cloned fragments, an ORF encoding the HaSNPV p40 was identified. The coding region was 966 bp long and potential to encode a 36.6kD pepetide. The HaSNPV p40 exhibits 98% identity with HzSNPV p40 at the nucleotide sequence. The two genes diverged significantly from BmNPV p40 and AcMNPV gp41.The predicted amino acid sequences have less than 45% homology between HaSNPV p40?HzSNPV p40 and BmNPV p40 or AcMNPV gp41, but four genes have a conserved hydrophilic domain. In this region they have 62% homology. Further more, we determined that Hind Ⅲ-H fragment links with J fragment in the genome and the two fragments were analasysed with four restriction endonucleases (BamH Ⅰ?EcoR Ⅰ?Hind Ⅲ?Pst Ⅰ) .