Topology of the Membrane-Associated Hepatitis C Virus Protein NS4B

Topology of the membrane-associated hepatitis C virus protein NS4B.

Hepatitis C virus (HCV) belongs to the Hepacivirus genus in the Flaviviridae family. Among the least known viral proteins in this family is the nonstructural protein NS4B, which has been suggested to be a part of the replication complex. Hydrophobicity plots indicate a common profile among the NS4B proteins from different members of the Flaviviridae family, suggesting a common function. In orde...

Dual topology of the processed hepatitis C virus protein NS4B is influenced by the NS5A protein.

Among the least-known hepatitis C virus proteins is the non-structural protein 4B (NS4B). It localizes to the endoplasmic reticulum (ER) membrane and induces membrane changes, resulting in a membranous web that is reported to be the locale for virus replication. A model was presented previously for the topology of recombinant HCV NS4B of the 1a genotype based on in vitro data. In this model, th...

Palmitoylation and polymerization of hepatitis C virus NS4B protein.

Hepatitis C Virus (HCV) NS4B protein induces a specialized membrane structure which may serve as the replication platform for HCV RNA replication. In the present study, we demonstrated that NS4B has lipid modifications (palmitoylation) on two cysteine residues (cysteines 257 and 261) at the C-terminal end. Site-specific mutagenesis of these cysteine residues on individual NS4B proteins and on a...

Analysis of Immumoreactivity of Heterologously Expressed Non-structural Protein 4B (NS4B) from Hepatitis C Virus (HCV) Genotype 1a

Background: Detection of hepatitis C virus specific antibodies is the initial step in chronic HCV diagnosis.  HCV NS4B is among the most immunogenic HCV antigens and has been widely used in commercial Enzyme Immunoassays (EIA). Additionally, NS4B, a key protein in the virus replication, can be an alternative target for antiviral therapy. Objectives: Development of a new method for high-level ex...

Modulation of the hepatitis C virus RNA-dependent RNA polymerase activity by the NS3 helicase and the NS4B membrane protein