Molecular dissection of hepatitis C virus expression

Area of Science:

• Hepatology
• Virology
• Molecular Biology

Background:

• The 5' untranslated region (5' UTR) of the hepatitis C virus (HCV) genome is crucial for viral gene expression.
• The 5' UTR is a potential target for antiviral therapies.

Purpose of the Study:

• To analyze the functional role of the HCV 5' UTR in vivo and in vitro.
• To investigate the interaction of cellular proteins with the HCV 5' UTR.

Main Methods:

• Generation of transgenic mice with a reporter gene containing the complete HCV 5' UTR.
• Analysis of cellular protein binding to the 5' UTR using gel shift assays and affinity purification.
• Comparison of protein-RNA complex formation in adult and young mice, as well as in human liver extracts.

Main Results:

• Transgenic mice showed protein accumulation specifically in periportal hepatocytes.
• Gel shift analysis revealed the presence of trans-acting proteins binding to a specific cis-acting element within the HCV 5' UTR in adult mice and humans, but not in young mice.
• Evidence suggests these proteins recognize a stemmed RNA structure within the 5' UTR.

Conclusions:

• Cellular factors regulate HCV 5' UTR expression in a tissue- and differentiation-specific manner.
• The binding of specific proteins to the HCV 5' UTR is age-dependent in mice.
• These findings highlight the importance of host-viral interactions in HCV replication and suggest potential therapeutic targets.