title: Autophagy protein ATG5 interacts transiently with the hepatitis C virus RNA polymerase (NS5B) early during infection.
abstract: Autophagy is an important cellular process by which ATG5 initiates the formation of double membrane vesicles (DMVs). Upon infection, DMVs have been shown to harbor the replicase complex of positive-strand RNA viruses such as MHV, poliovirus, and equine arteritis virus. Recently, it has been shown that autophagy proteins are proviral factors that favor initiation of hepatitis C virus (HCV) infection. Here, we identified ATG5 as an interacting protein for the HCV NS5B. ATG5/NS5B interaction was confirmed by co-IP and metabolic labeling studies. Furthermore, ATG5 protein colocalizes with NS4B, a constituent of the membranous web. Importantly, immunofluorescence staining demonstrated a strong colocalization of ATG5 and NS5B within perinuclear regions of infected cells at 2 days postinfection. However, colocalization was completely lacking at 5DPI, suggesting that HCV utilizes ATG5 as a proviral factor during the onset of viral infection. Finally, inhibition of autophagy through ATG5 silencing blocks HCV replication.
authors.affiliation: Institut National de la Recherche Scientifique-Institut Armand-Frappier (INRS-IAF), Laval, Québec, Canada.
authors.forename: Carl
authors.initials: C
authors.lastname: Guévin
authors.forename: David
authors.initials: D
authors.lastname: Manna
authors.forename: Claudia
authors.initials: C
authors.lastname: Bélanger
authors.forename: Kouacou V
authors.initials: KV
authors.lastname: Konan
authors.forename: Paul
authors.initials: P
authors.lastname: Mak
authors.forename: Patrick
authors.initials: P
authors.lastname: Labonté
mesh_terms: D000071187:Autophagy-Related Protein 5; D002460:Cell Line; D005786:Gene Expression Regulation / Q000502:physiology; D020868:Gene Silencing; D016174:Hepacivirus / Q000201:enzymology*; D006801:Humans; D008869:Microtubule-Associated Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D020798:Two-Hybrid System Techniques; D017361:Viral Nonstructural Proteins / Q000235:genetics / Q000378:metabolism*; D014779:Virus Replication; D012324:RNA-Dependent RNA Polymerase
chemical_list: D000071187:Autophagy-Related Protein 5; D008869:Microtubule-Associated Proteins; D017361:Viral Nonstructural Proteins; C502778:ATG5 protein, human; C087036:NS-5 protein, hepatitis C virus; D012324:RNA-Dependent RNA Polymerase