STRUCTURE OF HEPATITIS B CORE AND E PROTEINS

本项目的总体目标是阐明 B型肝炎核心抗原（HBcAg）与 B e型肝炎（HBeAg）抗原。 这些抗原是一种复合物的一部分 B型肝炎病毒抗原和宿主抗体系统， 描述人类感染这种病毒的特征。 存在这些 抗原和抗体广泛用于诊断感染， 也用于疾病的预后。 HBeAg蛋白，分享其大部分 氨基酸序列与HBcAg相同，但抗原性不同。 这种抗原性差异必然反映了蛋白质结构的差异。 虽然HBeAg在疾病中的作用尚不清楚，但它已被广泛应用。 最近表明，它可能在慢性疾病的发展中发挥作用。 新生儿感染期间感染。 更详细地理解 这种蛋白质的结构可以更好地了解其 功能 这两种蛋白质之间的结构和抗原关系将 使用酿酒酵母表达系统进行研究。 两 将使用不同的表达载体。 一个指导合成， 蛋白质的细胞内积累，而另一个进行 蛋白质的合成和分泌。 蛋白质对应于 HBCAG、HBeAg和这些的突变体将从每一种中产生和纯化。 这些系统，并受到物理，化学和免疫化学 分析. 这些研究将使我们能够确定 环境（细胞内与细胞外）的物理和 这些蛋白质的抗原结构。

The overall goal of this project is to elucidate the structural basis for the antigenic differences between the hepatitis B core (HBcAg) and Hepatitis B e (HBeAg) antigens. These antigens are part of a complex system of Hepatitis B viral antigens and host antibodies which characterize human infection by this virus. The presence of these antigens and anti-bodies are widely used for diagnosis of infection and also for prognosis of the disease. HBeAg protein, shares most of its amino acid sequence with the HBcAg, and yet is antigenically distinct. Such antigenic differences must reflect protein structural differences. Although the function of HBeAg during the disease is unknown, it has been recently suggested that it may play a role in the development of chronic infection during neonatal infection. A more detailed understanding of the structure of this protein may provide better insight into its function. The structural and antigenic relationship between these two proteins will be investigated using Saccharomyces cerevisiae expression systems. Two different expression vectors will be used. One directs synthesis and intra-cellular accumulation of the protein while the other carries out synthesis and secretion of the protein. Proteins corresponding to the HBCAG, HBeAg and mutants of these will be produced and purified from each of these systems and subjected to physical, chemical, and immunochemical analysis. These studies will allow us to determine the role of the environment (intracellular vs extracellular) on the physical and antigenic structure of these proteins.