Functional Characterization of Naturally Occurring Variants of Human Hepatitis B Virus Containing the Core Internal Deletion Mutation

AUTOR(ES)

Yuan, Thomas Ta-Tung

FONTE

American Society for Microbiology

RESUMO

Naturally occurring variants of human hepatitis B virus (HBV) containing the core internal deletion (CID) mutation have been found frequently in HBV carriers worldwide. Despite numerous sequence analysis reports of CID variants in patients, in the past decade, CID variants have not been characterized functionally, and thus their biological significance to HBV infection remains unclear. We report here two different CID variants identified from two patients that are replication defective, most likely due to the absence of detectable core protein. In addition, we were unable to detect the presence of the precore protein and e antigen from CID variants. However, the production of polymerase appeared to be normal. The replication defect of the CID variants can be rescued in trans by complementation with wild-type core protein. The rescued CID variant particles, which utilize the wild-type core protein, presumably are enveloped properly since they can be secreted into the medium and band at a position similar to that of mature wild-type Dane particles, as determined by gradient centrifugation analysis. Our results also provide an explanation for the association of CID variants with helper or wild-type HBV in nature. The significance of CID variants in HBV infection and pathogenesis is discussed.

Documentos Relacionados

• Subtype-Independent Immature Secretion and Subtype-Dependent Replication Deficiency of a Highly Frequent, Naturally Occurring Mutation of Human Hepatitis B Virus Core Antigen
• The Mechanism of an Immature Secretion Phenotype of a Highly Frequent Naturally Occurring Missense Mutation at Codon 97 of Human Hepatitis B Virus Core Antigen
• Naturally occurring missense mutation in the polymerase gene terminating hepatitis B virus replication.
• Effects of a naturally occurring mutation in the hepatitis B virus basal core promoter on precore gene expression and viral replication.
• Naturally Occurring Mutations Define a Novel Function of the Hepatitis B Virus Core Promoter in Core Protein Expression