Hepatitis C virus infection activates an innate pathway involving IKK-α in lipogenesis and viral assembly.

TitleHepatitis C virus infection activates an innate pathway involving IKK-α in lipogenesis and viral assembly.
Publication TypeJournal Article
Year of Publication2013
AuthorsLi Q, Pène V, Krishnamurthy S, Cha H, Liang JT
JournalNature medicine
Volume19
Issue6
Pagination722-9
Date Published2013 Jun
Abstract

Hepatitis C virus (HCV) interacts extensively with host factors to not only establish productive infection but also trigger unique pathological processes. Our recent genome-wide siRNA screen demonstrated that IκB kinase-α (IKK-α) is a crucial host factor for HCV. Here we describe a new nuclear factor κB (NF-κB)-independent and kinase-mediated nuclear function of IKK-α in HCV assembly. HCV, through its 3' untranslated region, interacts with DEAD box polypeptide 3, X-linked (DDX3X) to activate IKK-α, which translocates to the nucleus and induces a CBP/p300-mediated transcriptional program involving sterol regulatory element-binding proteins (SREBPs). This innate pathway induces lipogenic genes and enhances core-associated lipid droplet formation to facilitate viral assembly. Chemical inhibitors of IKK-α suppress HCV infection and IKK-α-induced lipogenesis, offering a proof-of-concept approach for new HCV therapeutic development. Our results show that HCV uses a novel mechanism to exploit intrinsic innate responses and hijack lipid metabolism, which may contribute to high chronicity rates and the pathological hallmark of steatosis in HCV infection.

DOI10.1371/journal.pntd.0002460
Alternate JournalNat. Med.