Interplay between host cell and hepatitis C virus in regulating viral replication.

Viral life cycle as that of the hepatitis C virus (HCV) completely relies on host cell infrastructure, presupposing that the virus has evolved mechanisms to utilize and control all cellular molecules or pathways required for viral life cycle. Hence, HCV must have acquired the ability to gain access to key pathways controlling processes, such as cell growth, apoptosis and protein synthesis, which are all considered to also be crucial for liver regeneration. This occurs in a balanced way permitting persistent replication of viral genomes and production of infectious particles without endangering host cell viability and survival. In particular during the last decade, accumulating evidence indicates that HCV utilizes signaling pathways of the host with major impact on cellular growth, viability, cell cycle or cellular metabolism, such as epidermal growth factor-receptor mediated signals, the PI3K/Akt cascade or the family of Src kinases. Furthermore, HCV specifically interacts with parts of the cellular machinery involved in protein translation, processing, maturation and transport, such as components of the translation complex, the heat shock protein family, the immunophilins or the vesicle-associated membrane protein-associated proteins A and B. The present review focuses on the interplay between viral proteins and these factors of the host cell enabling the virus to utilize host cell infrastructure.