GENETIC ANALYSIS OF HDV/HBV INTERACTION

丁型肝炎病毒（HDV）开创了动物病毒窝藏的先例， 显示与植物类病毒相似性的环状RNA基因组， 类病毒 因此，HDV代表了人类中的一类新的病毒因子 具有致病特性。 此外，HDV是一种缺陷病毒， 无法自主复制，但需要 共感染B型肝炎病毒（HBV）以引发感染。 病毒 颗粒由HBV表面抗原的包膜组成， RNA基因组和携带δ抗原的HDV编码多肽。 HDV病毒粒子进入易感细胞后， 自主地，但需要HBV包膜蛋白的存在才能 病毒颗粒的形成将确保繁殖。 HDV 可以被认为是需要HBV包膜的有缺陷的药物， 抑制辅助HBV复制的干扰剂。 这 该提案将重点关注HBV和HDV之间的相互作用，包括 识别HBV和HDV形成所需的功能 感染性HDV颗粒，以及HDV对 HBV复制。 将开发一种离体组织培养系统 以协助完成此次调查 的具体目标 提出了以下几点建议：1）确定实验条件， HDV颗粒的体外生产; 2）建立HDV颗粒的体外生产条件。 体外感染性试验; 3）鉴定HBV表面结构域 HDV颗粒的形态发生和感染性所需的蛋白质 体外; 4）鉴定所需的δ抗原的结构域， 与HDV RNA和HBV表面蛋白相互作用以形成 5）研究其它HDV ORF的表达需要 用于生产HDV颗粒的产品;以及6）研究 HDV复制和颗粒形成对HBV复制的影响。 这些问题的答案应该提供有价值的见解，在设计 抗病毒策略。 HBV上结构域的鉴定 与肝细胞上HDV受体结合的表面蛋白应 也方便了。 这种受体的鉴定可能有助于 也从这个项目的成就，并将被视为一个 这个项目的未来发展。

Hepatitis delta virus (HDV) set the precedent for an animal virus harboring a circular RNA genome that displays similarities with the plant viroids and virusoids. As such, HDV represents a new class of viral agent in humans with pathogenic properties. In addition, HDV is a defective virus that cannot replicate autonomously, but requires the helper functions of coinfecting hepatitis B virus (HBV) to initiate an infection. The viral particle is composed of an envelope of HBV surface antigen which encloses the RNA genome and an HDV encoded polypeptide bearing the delta antigen. Upon entry of HDV virions into susceptible cells, HDV RNA replicates autonomously, but the presence of HBV envelope proteins is required for the formation of viral particles that will ensure propagation. Therefore, HDV can be considered a defective agent that needs the HBV envelope, and an interfering agent that suppresses the replication of the helper HBV. This proposal will focus on the interaction between HBV and HDV, including the identification of the HBV and HDV functions required for the formation of infectious HDV particles, and the interference phenomenon of HDV on the replication of HBV. An in vitro tissue culture system will be developed to facilitate the achievement of this investigation. The specific aims of this proposal are: 1) to determine the experimental conditions for the production of HDV particles In vitro; 2) to establish the conditions for infectivity assays in vitro; 3) to identify the domains of the HBV surface proteins required for the morphogenesis and infectivity of HDV particles in vitro; 4) to identify the domains of the delta antigen required for the interaction with HDV RNA and HBV surface protein for formation of particles; 5) to study the requirement for the expression of other HDV ORF products for the production of HDV particles; and 6) to study the effect of HDV replication and particle formation on the replication of HBV. Answers to these questions should provide valuable insight in the designing of antiviral strategies. Identification of the domain(s) on the HBV surface protein that bind to the HDV receptor on the hepatocyte should be facilitated as well. The identification of such a receptor may benefit also from the achievement of this project and will be considered as a future extension of this project.