Pathogenesis and Gene Regulation of Entomopoxvirus

描述(申请人提供)：虫痘病毒(EPV)是最多的 脊椎动物正痘病毒(OPV)的远亲，如牛痘(VV) 天花(天花)。脊椎动物痘病毒在 转移受感染宿主的免疫和其他防御反应。我们有 完成了蚕豆核型多角体病毒(Amacta moorei，AmEPV)的基因组序列 几种在细胞培养中容易生长和容易形成的EPV 被操纵了。AmEPV会导致昆虫的致命性传播性感染，但 缺乏作为致病因子的免疫修饰物基因 脊椎动物痘病毒。我们计划重点关注AmEPV感染的主要方面 毒蛾幼虫作为痘病毒致病模型的研究 在低等真核生物中。我们有三个具体目标。第一个具体目标是 对感染沙门氏菌幼虫的病理生物学进行量化和完整的表征 AMEPV通过直接注射或喂食(每OS)。这些研究将 包括感染全程、传播评估、产量和 细胞参与。在我们的第二个具体目标中，我们将确定为什么AMEPV， 与任何其他已知的痘病毒不同的是，痘病毒编码病毒的第三个或额外的亚基 编码的聚(A)聚合酶，一种对病毒信使核糖核酸合成必不可少的酶。这 该病毒的不同寻常的特征有望洞察一些基本的生物学 控制所有痘病毒的基因表达。在我们的第三个具体目标中，我们将 研究特定基因在AmEPV感染的病理生物学中的作用。我们 将首先集中研发一种“库尼茨型”的蛋白酶抑制剂和一种1365 氨基酸ABC转运蛋白基因，这两个基因在任何 其他病毒。我们将首先使用一个过程生成“击倒”，该过程通过 设计还将告诉我们，基因是否对生长至关重要。病毒 将评估所选基因的缺失对发病机制的影响。我们 我还计划扩大这些研究，并检查病毒编码的超氧化物 超氧化物歧化酶(SOD)和凋亡抑制蛋白(IAP)作为其他 可能在感染过程中发挥重要作用的基因。每个基因 将被评估为生化功能。总的来说，建议的 实验将阐明病毒通过哪些额外的多样性来对抗 寄主生物体的防御。

DESCRIPTION (provided by applicant): Entomopoxviruses (EPV's) are the most distant relatives of vertebrate orthopoxviruses (OPV's) such as vaccinia (VV) and variola (smallpox). Vertebrate poxviruses, are particularly masterful in deflecting the immune and other defense responses of the infected host. We have completed the genomic sequence of the EPV from Amsacta moorei (AmEPV), one of the few EPV's which can be easily grown in cell culture and readily manipulated. AmEPV, causes a lethal, disseminated infection of insects but is devoid of the immune modifier genes known to act as virulence factors of vertebrate poxviruses. We plan to focus on the major aspects of AmEPV infection of Lymantria dispar (LD) larvae as a model for the pathogenesis of poxviruses in lower eukaryotes. We have three Specific Aims. The first Specific Aim is to quantify and completely characterize the pathobiology of larvae infected with AmEPV by either direct injection or by feeding (per os). These studies will include a full time course of infection, evaluation of spread, yields and cellular involvement. In our second Specific Aim, we will determine why AmEPV, unlike any other known poxvirus encodes a third or "extra" subunit of the viral encoded poly (A) polymerase, an enzyme essential for viral mRNA synthesis. This unusual feature of the virus promises insight into some of the basic biology of gene expression governing all poxviruses. In our third Specific Aim, we will examine the role of specific genes on the pathobiology of AmEPV infections. We will initially concentrate on a "Kunitz-type" protease inhibitor and a 1365 amino acid ABC transporter gene neither of which have been reported in any other virus. We will begin by generating "knockouts" using a procedure which by design will also tell us whether the gene is essential for growth. Virus deleted for the selected gene will be evaluated for effects on pathogenesis. We also plan to extend these studies and examine virus encoded superoxide dismutase (SOD) and inhibitor of apoptosis protein (IAP) as examples of other genes likely to play significant roles in the infectious process. Each gene will be evaluated for biochemical function. Collectively, the proposed experiments will elucidate added diversity by which viruses counter the defenses of host organisms.