【摘要】 用BamHI、EcoRV、HindIII、KpnI、PstI和XbaI六种限制性内切酶消化HaSNPVC1株基因组DNA ,电泳后形成的大于 40 0bp的片段数分别为 11、31、13、6、7和 2 5条。预计整个基因组长度为 130 .7kb左右。构建了HaSNPV基因组 6种限制性内切酶的物理图谱 ,并在图谱上定位了 5个同源重复区hr1、hr2、hr3、hr4和hr5以及多角体蛋白 (ph)基因、极早期基因 (ie1)、p10、几丁质酶 (chitinase)基因、DNA聚合酶基因 (DNApol)、解旋酶 (heli case)基因、超氧化物歧化酶基因 (sod)、碱性外切核酸酶基因 (alk exo)、蜕皮甾体尿苷二磷酸葡萄糖转移酶基因(egt)。HaSNPV的基因组结构与其他已知的病毒表现了很明显的差异。p10基因位于BamHI I片段 (1.89kb)上 ,其转录方向与多角体蛋白基因 (polh)相反。p10上游为 p2 6基因 ,下游为p74基因 ,p2 6和 p10基因转录方向一致 ,而 p74基因转录方向与前两者相反。p10基因编码区全长 2 6 1bp ,可编码分子量为 9.3kD ,由 87个氨基酸残基组成的多肽。编码区上游是一个富含AT区 ,在起始密码子ATG上游 - 5 2bp处有杆状病毒晚期基因启动子典型的转录起始位点元件TAAG ,而在翻译终止密码子TGA下游 2 0bp处有转录终止信号AATAAA。更多还原

【Abstract】 The genomic DNA of Helicoverpa armigera single nucleocapsid nucleopolyhedrovirus (C1 clone) was digested with Bam HI, Eco RV, Hin dIII, Kpn I, Pst I and Xba I, respectively, and formed 11, 31, 13, 6, 7, and 25 fragments larger than 400 bp, respectively. The size of genome was estimated to be about 130.7 kb. A detailed physical map was constructed for the six restriction enzymes. The five homologous region, hr1, hr2, hr3, hr4 and hr5, and the ten genes including polyhedrin gene ( ph ), immediate early gene( ie 1), p 74, p 10, chitinase gene, DNA directed DNA polymerase gene ( DNApol ), helicase gene, superoxide dismutase gene( sod ), alkaline exonuclease gene ( alk exo ), ecdysteroid UDP glucosyltransferase gene ( egt ) were identified and their locations in the genome were determined. The genome organization of HaSNPV is quite different from those of other NPVs ever determined. The p 10 gene was located in the fragment Bam HI I(1.89 kb) with the transcriptional direction opposite to the polyhedrin gene. Upstream and downstream of the p 10 gene were p 26 and p 74 gene, respectively. The transcriptional direction of p 26 is the same as that of p 10 gene, and opposite to that of the p 74 gene. The ORF encoding p 10 was 261 nucleotide long and encoding a putative 87 amino acid polypeptide of 9.3 kD. The immediate upsteam region of the p 10 was an A rich region, and a conserved TAAG motif, associated with transcriptional start sites in other p 10 genes, was identified at a site 52 nucleotides upstream of the start codon ATG. A putative polyadenylation signal, AATAAA, was found 20 nucleotides downstream of the termination codon.更多还原