A small yeast RNA blocks hepatitis C virus internal ribosome entry site (HCV IRES)-mediated translation and inhibits replication of a chimeric poliovirus under translational control of the HCV IRES element.
Hepatitis C virus (HCV) infection frequently leads to chronic hepatitis and cirrhosis of the liver and has been linked to development of hepatocellular carcinoma. We previously identified a small yeast RNA (IRNA) capable of specifically inhibiting poliovirus (PV) internal ribosome entry site (IRES)-mediated translation. Here we report that IRNA specifically inhibits HCV IRES-mediated translation both in vivo and in vitro. A number of human hepatoma (Huh-7) cell lines expressing IRNA were prepared and characterized. Constitutive expression of IRNA was not detrimental to cell growth. HCV IRES-mediated cap-independent translation was markedly inhibited in cells constitutively expressing IRNA compared to control hepatoma cells. However, cap-dependent translation was not significantly affected in these cell lines. Additionally, Huh-7 cells constitutively expressing IRNA became refractory to infection by a PV-HCV chimera in which the PV IRES is replaced by the HCV IRES. In contrast, replication of a PV-encephalomyocarditis virus (EMCV) chimera containing the EMCV IRES element was not affected significantly in the IRNA-producing cell line. Finally, the binding of the La autoantigen to the HCV IRES element was specifically and efficiently competed by IRNA. These results provide a basis for development of novel drugs effective against HCV infection.
Das
S
S
Department of Microbiology and Immunology and Jonsson Comprehensive Cancer Center, School of Medicine, University of California, Los Angeles, California 90095, USA.
Ott
M
M
Yamane
A
A
Tsai
W
W
Gromeier
M
M
Lahser
F
F
Gupta
S
S
Dasgupta
A
A
D001324:Autoantigens / Q000378:metabolism; D006528:Carcinoma, Hepatocellular / Q000235:genetics; D006367:HeLa Cells; D016174:Hepacivirus / Q000187:drug effects* / Q000235:genetics / Q000502:physiology; D006526:Hepatitis C / Q000188:drug therapy; D006801:Humans; D008113:Liver Neoplasms / Q000235:genetics; D017955:Poliovirus / Q000502:physiology*; D014176:Protein Biosynthesis / Q000187:drug effects*; D012331:RNA, Fungal / Q000494:pharmacology*; D012261:Ribonucleoproteins / Q000378:metabolism; D014407:Tumor Cells, Cultured; D014779:Virus Replication / Q000187:drug effects*; D015003:Yeasts / Q000235:genetics*; D000097585:SS-B Antigen
D001324:Autoantigens; D012331:RNA, Fungal; D012261:Ribonucleoproteins; D000097585:SS-B Antigen