Wu Yueh-Lung, Liu Catherine Y Y, Wu Carol P, Wang Chia-Hung, Lee Song-Tay, Chao Yu-Chan
Institute of Biotechnology, National Cheng Kung University, No.1, University Road, Tainan 701, Taiwan.
Virus Res. 2008 Aug;135(2):247-54. doi: 10.1016/j.virusres.2008.04.001. Epub 2008 May 16.
HzNV-1 is a non-occluded virus belongs to the family of the baculovirus. One of the first detectable transcripts expressed by HzNV-1 virus infection is a 6.2 kb gene, hhi1, located in the HindIII-I fragment of the viral genome. Here we show that infection of baculovirus Autographa californica multiple nucleopolyhedrovirus (AcMNPV) could activate the expression of the hhi1 promoter. By using constructs containing progressive deletions of the upstream regulatory regions of the hhi1 gene, we demonstrated that the most highly activated area was located between nucleotides -62 to +277 of the hhi1 promoter. We subsequently searched the entire 130 kb AcMNPV genome and identified two baculovirus genes, ie1 and p35, that their cooperation is required for the activation of the hhi1 promoter. Further, by taking advantages of a baculovirus DNA chip and low background baculovirus gene expressions in the mammalian cells, we went on to identify a specific set of baculoviral genes, including orf21 and orf25, that could be specifically activated by the combination of ie1 and p35 genes. We conclude that a unique cooperative mechanism of ie1 and p35 exists in the genome of AcMNPV, which can activate the expression of a specific set of AcMNPV and HzNV-1 promoters.
HzNV-1是一种属于杆状病毒科的非包涵体病毒。HzNV-1病毒感染后最早可检测到的转录本之一是一个位于病毒基因组HindIII-I片段的6.2 kb基因hhi1。在此我们表明，苜蓿银纹夜蛾多粒包埋核型多角体病毒（AcMNPV）的感染可激活hhi1启动子的表达。通过使用含有hhi1基因上游调控区逐步缺失的构建体，我们证明了激活程度最高的区域位于hhi1启动子的核苷酸-62至+277之间。我们随后搜索了整个130 kb的AcMNPV基因组，并鉴定出两个杆状病毒基因ie1和p35，它们的协同作用是激活hhi1启动子所必需的。此外，利用杆状病毒DNA芯片以及哺乳动物细胞中杆状病毒基因表达背景较低的优势，我们继续鉴定出一组特定的杆状病毒基因，包括orf21和orf25，它们可被ie1和p35基因的组合特异性激活。我们得出结论，AcMNPV基因组中存在ie1和p35独特的协同机制，该机制可激活一组特定的AcMNPV和HzNV-1启动子的表达。
