Identification and chemical synthesis of a host cell receptor binding site on hepatitis B virus

ABSTRACT The entry of ecotropic murine leukemia virus (MLV) into cells requires the interaction of the envelope protein (Env) with its receptor, mouse cationic amino acid transporter 1 (mATRC1). An aspartic acid-to-lysine change at position 84 (D84K) of ecotropic Moloney MLV Env abolishes virus binding and infection. We recently identified lysine 234 (rK234) in mATRC1 as a residue that influences virus binding and infection. Here we show that D84K virus infection increased 3,000-fold on cells expressing receptor with an rK234A change and 100,000-fold on cells expressing an rK234D change. The stronger complementation of D84K virus infection by rK234D than by the rK234A receptor suggests that although the major reason for loss of infection of D84K and D84R virus is due to steric hindrance and charge repulsion, the loss of an interaction of D84 with receptor appears to contribute as well. Taken together, these results indicate that D84 is very close to rK234 of mATRC1 in the bound complex and there is likely an interaction between them. The definitive localization of the receptor binding site on SU should facilitate the design of chimeric envelope proteins that target infection to new receptors by replacing the receptor binding site with an exogenous ligand sequence.

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Mechanism of Suppression of Hepatitis B Virus Precore RNA Transcription by a Frequent Double Mutation

Journal of Virology ◽

10.1128/jvi.73.2.1239-1244.1999 ◽

1999 ◽

Vol 73 (2) ◽

pp. 1239-1244 ◽

Cited By ~ 120

Author(s):

Jie Li ◽

Victor E. Buckwold ◽

Man-wai Hon ◽

Jing-hsiung Ou

Keyword(s):

Hepatitis B Virus ◽

Binding Site ◽

Nuclear Receptor ◽

Receptor Binding ◽

Core Promoter ◽

Receptor Binding Site ◽

Rna Transcription ◽

Double Mutation ◽

The Core ◽

B Virus

ABSTRACT A double mutation which converts nucleotide 1765 from A to T and nucleotide 1767 from G to A is frequently found in the hepatitis B virus (HBV) genome isolated from HBV patients with chronic hepatitis symptoms. This double mutation is located in the core promoter that controls the transcription of the precore RNA and the core RNA. In addition, this double mutation also resides in the X protein coding sequence, converting codon 130 from Lys to Met and codon 131 from Val to Ile. Previous studies indicate that this double mutation removes a nuclear receptor binding site in the core promoter, suppresses specifically precore RNA transcription, and enhances viral replication. In this study, we further investigated how this double mutation suppresses precore RNA transcription. We found that this double mutation not only removed the nuclear receptor binding site but also created an HNF1 transcription factor binding site. Further transfection studies using Huh7 hepatoma cells indicate that the removal of the nuclear receptor binding site has no effect on the transcription of HBV RNAs, the two-codon change in the X protein sequence suppresses the transcription of both precore and core RNAs, and the creation of the HNF1 binding site restores the core RNA level. Hence, the specific suppression of precore RNA transcription by this frequent double-nucleotide mutation is the combined result of multiple factors.

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Replication of the Wild Type and a Natural Hepatitis B Virus Nucleocapsid Promoter Variant Is Differentially Regulated by Nuclear Hormone Receptors in Cell Culture

Journal of Virology ◽

10.1128/jvi.75.19.8937-8948.2001 ◽

2001 ◽

Vol 75 (19) ◽

pp. 8937-8948 ◽

Cited By ~ 33

Author(s):

Hong Tang ◽

Anneke K. Raney ◽

Alan McLachlan

Keyword(s):

Hepatitis B Virus ◽

Hepatitis B ◽

Binding Site ◽

Nuclear Hormone Receptor ◽

Wild Type ◽

Nucleotide Substitutions ◽

Receptor Binding Site ◽

Rna Transcription ◽

B Virus ◽

Replication Intermediates

ABSTRACT A natural hepatitis B virus (HBV) variant associated with seroconversion from HBeAg to anti-HBe antibody contains two nucleotide substitutions (A1764T and G1766A) in the proximal nuclear hormone receptor binding site in the nucleocapsid promoter. These nucleotide substitutions prevent the binding of the retinoid X receptor α (RXRα)–peroxisome proliferator-activated receptor α (PPARα) heterodimer without greatly altering the efficiency of binding of hepatocyte nuclear factor 4 (HNF4) to this recognition sequence. In addition, these nucleotide substitutions create a new binding site for HNF1. Analysis of HBV transcription and replication in nonhepatoma cells indicates that RXRα-PPARα heterodimers support higher levels of pregenomic RNA transcription from the wild-type than from the variant nucleocapsid promoter, producing higher levels of wild-type than of variant replication intermediates. In contrast, HNF4 supports higher levels of pregenomic RNA transcription from the variant than from the wild-type nucleocapsid promoter, producing higher levels of variant than of wild-type replication intermediates. HNF1 can support variant virus replication at a low level but is unable to support replication of the wild-type HBV genome. These observations indicate that the replication of wild-type and variant viruses can be differentially regulated by the liver-specific transcription factors that bind to the proximal nuclear hormone receptor binding site of the nucleocapsid promoter. Differential regulation of viral replication may be important in the selection of specific viral variants as a result of an antiviral immune response.

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Epitope–Paratope Interaction of a Neutralizing Human Anti-Hepatitis B Virus PreS1 Antibody That Recognizes the Receptor-Binding Motif

Vaccines ◽

10.3390/vaccines9070754 ◽

2021 ◽

Vol 9 (7) ◽

pp. 754

Author(s):

Jisu Hong ◽

Youngjin Choi ◽

Yoonjoo Choi ◽

Jiwoo Lee ◽

Hyo Jeong Hong

Keyword(s):

Hepatitis B Virus ◽

Hepatitis B ◽

Receptor Binding ◽

Neutralizing Antibody ◽

Hbv Infection ◽

Binding Motif ◽

Alanine Scanning Mutagenesis ◽

B Virus ◽

Complementarity Determining Regions

Hepatitis B virus (HBV) is a global health burden that causes acute and chronic hepatitis. To develop an HBV-neutralizing antibody that effectively prevents HBV infection, we previously generated a human anti-preS1 monoclonal antibody (1A8) that binds to genotypes A–D and validated its HBV-neutralizing activity in vitro. In the present study, we aimed to determine the fine epitope and paratope of 1A8 to understand the mechanism of HBV neutralization. We performed alanine-scanning mutagenesis on the preS1 (aa 19–34, genotype C) and the heavy (HCDR) and light (LCDR) chain complementarity-determining regions. The 1A8 recognized the three residues (Leu22, Gly23, and Phe25) within the highly conserved receptor-binding motif (NPLGFFP) of the preS1, while four CDR residues of 1A8 were critical in antigen binding. Structural analysis of the epitope–paratope interaction by molecular modeling revealed that Leu100 in the HCDR3, Ala50 in the HCDR2, and Tyr96 in the LCDR3 closely interacted with Leu22, Gly23, and Phe25 of the preS1. Additionally, we found that 1A8 also binds to the receptor-binding motif (NPLGFLP) of infrequently occurring HBV. The results suggest that 1A8 may broadly and effectively block HBV entry and thus have potential as a promising candidate for the prevention and treatment of HBV infection.

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