title: Silencing of hepatitis A virus infection by small interfering RNAs.
abstract: Infection by hepatitis A virus (HAV) can cause acute hepatitis and, rarely, fulminant liver failure, in particular in patients chronically infected with hepatitis C virus. Based on our previous observation that small interfering RNAs (siRNAs) can silence translation and replication of the firefly luciferase-encoding HAV replicon, we now exploited this technology to demonstrate the effect of siRNAs on viral infection in Huh-7 cells. Freshly and persistently infected cells were transfected with siRNAs targeting various sites in the HAV nonstructural genes. Compared to a single application, consecutive siRNA transfections targeting multiple sequences in the viral genome resulted in a more efficient and sustained silencing effect than a single transfection. In most instances, multiple applications of a single siRNA led to the emergence of viral escape mutants with mutated target sites that rendered these genomes resistant to RNA interference (RNAi). Efficient and sustained suppression of the viral infectivity was achieved after consecutive applications of an siRNA targeting a computer-predicted hairpin structure. This siRNA holds promise as a therapeutic tool for severe courses of HAV infection. In addition, the results provide new insight into the structural bases for sequence-specific RNAi.
authors.affiliation: Institute of Medical Molecular Biology, University of Lübeck, Ratzeburger Allee 160, 23562 Lübeck, Germany. koussov@molbio.uni-luebeck.de
authors.forename: Yuri
authors.initials: Y
authors.lastname: Kusov
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Kanda
authors.forename: Ann
authors.initials: A
authors.lastname: Palmenberg
authors.forename: Jean-Yves
authors.initials: JY
authors.lastname: Sgro
authors.forename: Verena
authors.initials: V
authors.lastname: Gauss-Müller
mesh_terms: D045744:Cell Line, Tumor; D020868:Gene Silencing / Q000187:drug effects*; D016174:Hepacivirus / Q000187:drug effects* / Q000235:genetics; D006505:Hepatitis / Q000235:genetics / Q000378:metabolism / Q000517:prevention & control*; D006801:Humans; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000737:chemistry / Q000235:genetics / Q000494:pharmacology*; D012367:RNA, Viral / Q000096:biosynthesis* / Q000235:genetics; D014779:Virus Replication / Q000187:drug effects / Q000235:genetics
chemical_list: D034741:RNA, Small Interfering; D012367:RNA, Viral