乙型肝炎病毒基因组剪接变异体结构分析

Structural analysis of spliced variants of hepatitis B virus genomes

目的 了解乙型肝炎病毒 (HBV)基因组剪接变异体的基因结构及特点。方法 从慢性乙型肝炎患者血清中扩增并克隆HBV基因组剪接变异体DNA ,测序并比较基因结构特点。结果 共获得 10种HBV基因组剪接变异体 ,基因组大小介于 76 5～ 2 0 39bp之间。导致剪接变异体产生的 5′端供体位点和 3′端受体位点各 6个。HBV基因组剪接变异体在C、前 S1、前 S2及S编码区存在不同程度的缺失 ,但均保留与致病密切相关的X基因以及病毒复制、包装所必须的DNA序列。

Objective To study the structure of spliced variants of hepatitis B virus (HBV) genomes and elucidate their potential pathogenicity. Methods Amplified the spliced variants of hepatitis B virus genomes by mean of PCR from the serum of the patients with chronic hepatitis B, sequenced and analysis the characteristics of such genomes. Results 10 different types of the spliced variants of hepatitis B virus genomes were obtained with the molecular weight ranging from 765 bp to 2039 bp. There were 6 splicing donor sites and 6 accepter sites, respectively in HBV genomes. All spliced variants showed one or more deletions in the regions coding for core, preS1, preS2 and surface protein, while retained thepathogenic X gene and cis elements which were essential for viral replication and packaging. Conclusions Spliced variants of hepatitis B virus genomes were commonly detected in the serum from chronic Hepatitis B patients, the characteristic structure of such variants implied that they might closely co-related with the pathogenicity of HBV.