%0 Journal Article %A Suzuki, Ryosuke %A Matsuura, Yoshiharu %A Suzuki, Tetsuro %A Ando, Ayako %A Chiba, Joe %A Harada, Shizuko %A Saito, Izumu %A Miyamura, Tatsuo %T Nuclear localization of the truncated hepatitis C virus core protein with its hydrophobic C terminus deleted %D 1995 %J Journal of General Virology, %V 76 %N 1 %P 53-61 %@ 1465-2099 %R https://doi.org/10.1099/0022-1317-76-1-53 %I Microbiology Society, %X SUMMARY The core protein of hepatitis C virus (HCV) is considered to be cleaved from the N terminus of the large precursor polyprotein by cellular signalase. The HCV cDNA encoding the core protein was expressed (i) in monkey COS cells by a plasmid expression vector driven by the SRα promoter, and (ii) in insect cells by a recombinant baculovirus. The expressed product had an M r of 22000 and was located in the cytoplasm. When the C-terminal hydrophobic domains were deleted, however, the truncated core proteins were translocated into the nucleus. The truncated core proteins were located in the nucleus even when they were expressed as a fusion protein with E. coli β-galactosidase, which is essentially localized in the cytoplasm. Plasmids containing HCV cDNAs with a deletion in one of the regions encoding clusters of basic amino acids were expressed in COS cells and the localization of the core protein was examined. The residues PRRGPR were suggested to play an important role in nuclear localization. HCV is an RNA virus and its life cycle was originally considered to be confined to the cytoplasm; the present study, however, suggests that the HCV core protein can translocate into the nucleus under certain circumstances. %U https://www.microbiologyresearch.org/content/journal/jgv/10.1099/0022-1317-76-1-53