HCV Virion and Its Life Cycle
Hepatitis C virus is a small enveloped virus with a 9.6 kb positive-sense single-stranded RNA genome that encodes a unique large polyprotein, which is processed by cellular and virally encoded proteases to produce at least 10 mature structural and nonstructural (NS) proteins (Figure 2). Amongst the structural proteins, the two envelope glycoproteins, E1 and E2, are essential components of the HCV virion envelope and are necessary for viral entry and fusion with cellular membrane. The latter is an important step for the release of HCV nucleocapsid in the cell cytoplasm and initiation of HCV polyprotein translation in a membranous web made of the NS proteins and host cell proteins called 'replication complex', located in close contact with perinuclear membranes. HCV 5'-nontranslated region contains a highly structured element, called internal ribosome entry site (IRES), which is essential for the initiation of HCV polyprotein translation. Amongst the NS proteins, the NS3 serine-like protease and the RNA-dependent RNA polymerase (RdRp), which is encoded by the NS5 region, are essential for viral maturation and replication, and therefore represent ideal targets for the development of small molecule anti-HCV compounds.[11,12] Genome encapsidation occurs in the endoplasmic reticulum and nucleocapsids are enveloped and matured into the Golgi apparatus before they are released in the pericellular space by exocytosis (Figure 1).
Aliment Pharmacol Ther. 2008;27(10):866-884. © 2008 Blackwell Publishing
Cite this: Review Article: Novel Therapeutic Options for Chronic Hepatitis C - Medscape - May 15, 2008.