WOODCHUCK VIRUS--MOLECULAR BIOLOGICAL STUDIES

土拨鼠肝炎病毒（WHV）是分类和血清学 与B型肝炎病毒（HBV）有关。 感染这些病毒 病毒与急性和慢性肝炎及肝细胞 癌在各自的宿主，这些协会似乎是 本质上是病因学的。 因此，土拨鼠的WHV感染提供了一种 相关的和方便的模型来了解HBV感染的 人类 进行了以下实验：（1）变异性 测定了感染动物中WHV基因组的含量。(2)血清池 发现有和没有缺陷的病毒诱导相同的 慢性携带者的百分比。 这表明， WHV接种物中的缺陷病毒不是WHV接种的先决条件。 建立持续性嗜肝DNA病毒感染。(3)寡核苷酸 定向诱变用于将点突变引入 前核心和X基因以及开放阅读框5和6，以确定 这些基因在土拨鼠病毒复制中的重要性 转染测定。(4)克隆了WHV和HBVX基因启动子 导入载体pSVOCAT中，以比较人和 土拨鼠细胞(5)在制备中克隆了WHV的纽约株 进行DNA测序

The woodchuck hepatitis virus (WHV) is taxonomically and serologically related to the hepatitis B virus (HBV). Infection with each of these viruses is associated with acute and chronic hepatitis and hepatic cell carcinoma in their respective hosts and these associations appear to be etiological in nature. Thus, WHV infection of woodchucks provides a relevant and convenient model for understanding HBV infections of humans. The following experiments were performed: (1) The variability of WHV genomes in an infected animal was determined. (2) Serum pools with and without defective virus were found to induce the same percentage of chronic carriers. This suggests that the presence of defective virus in a WHV inoculum is not a prerequisite for the establishment of persistent hepadnavirus infections. (3) Oligonucleotide directed mutagenesis was used to introduce point mutations in the precore and X genes as well as open reading frames 5 and 6 to determine the importance of these genes in virus replication using woodchuck transfection assays. (4) The WHV and HBV X gene promoters were cloned into the vector pSVOCAT to compare promoter strength in human and woodchuck cells. (5) A New York strain of WHV was cloned in preparation for DNA sequencing.