Abstract
Although information regarding morphogenesis of the hepatitis C virus (HCV) is accumulating, the mechanism(s) by which the HCV genome encapsidated remains unknown. In the present study, in cell cultures producing HCV, the molecular ratios of 3’ end- to 5’ end-regions of the viral RNA population in the culture medium were markedly higher than those in the cells, and the ratio was highest in the virion-rich fraction. The interaction of the 3’ untranslated region (UTR) with Core in vitro was stronger than that of the interaction of other stable RNA structure elements across the HCV genome. A foreign gene flanked by the 3’ UTR was encapsidated by supplying both viral NS3-NS5B proteins and Core-NS2 in trans. Mutations within the conserved stem-loops of the 3’ UTR were observed to dramatically diminish packaging efficiency, suggesting that the conserved apical motifs of the 3´ X region are important for HCV genome packaging. This study provides evidence of selective packaging of the HCV genome into viral particles and identified that the 3’ UTR acts as a cis-acting element for encapsidation.
Highlights
It is known that positive strand RNA viruses package their genome via replication-coupled processes [1,2,3]
Cell culture systems provide a powerful tool for deciphering the life cycle of the hepatitis C virus (HCV), the mechanisms of encapsidation of the viral genome into infectious particles remain to be uncovered
We characterized the properties of HCV RNAs in a cell culture system by determining their integrity in virus-replicating cells and in culture supernatants, and we found that over-distributed
Summary
It is known that positive strand RNA viruses package their genome via replication-coupled processes [1,2,3]. For several viruses, viral particle assembly occurs via recognition of particular sequences or structures termed packaging signals that are unique to the viral genes. These signals are more conserved than other parts of the viral genomes and are usually highly structured. Mutations in the 3’ X region were shown to abort replication [6,7], which illustrates the important role of the 3’ UTR in replication Both the length and the composition of the poly (U/UC) tract are critical for HCV genome replication [8]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
