Replication of a hepatitis A virus replicon detected by genetic recombination in vivo.
Unlike other picornaviruses, hepatitis A virus (HAV) replicates so inefficiently in cell culture that the study of its RNA biosynthesis presents a major experimental challenge. To assess viral RNA replication independent of particle formation, a subgenomic replicon representing a self-replicating RNA was constructed by replacing the P1 domain encoding the capsid proteins with the firefly luciferase sequence. Although translation of the HAV replicon was as efficient as a similar poliovirus replicon, the luciferase activity derived from replication of the HAV construct was more than 100-fold lower than that of poliovirus. The replication capacity of the HAV replicon was clearly demonstrated by its ability to recombine genetically with a non-viable, full-length HAV genome that served as capsid donor and thus to rescue a fully infectious virus. In contrast to a replication-deficient replicon, co-expression of the genetically marked and replication-competent HAV replicon with several lethally mutated HAV genomes resulted in the successful rescue of infectious HAV with a unique genetic marker. Our data suggest: (i) that autonomous HAV RNA replication does not require sequences for the HAV structural proteins; and (ii) that low-level genome replication can unequivocally be demonstrated by the rescue of infectious virus after co-expression with non-viable genomes.
Gauss-Müller
Verena
V
Institute of Medical Molecular Biology, Medical University of Lübeck, Ratzeburger Allee 160, D-23538 Lübeck, Germany1.
Kusov
Yuri Y
YY
Institute of Medical Molecular Biology, Medical University of Lübeck, Ratzeburger Allee 160, D-23538 Lübeck, Germany1.
D000818:Animals; D002460:Cell Line; D016679:Genome, Viral; D030041:Hepatitis A virus / Q000235:genetics*; D008156:Luciferases / Q000235:genetics; D012367:RNA, Viral / Q000096:biosynthesis*; D011995:Recombination, Genetic; D012093:Replicon; D015678:Viral Structural Proteins / Q000235:genetics; D014779:Virus Replication
D012367:RNA, Viral; C096539:VP1 protein, hepatitis A virus; D015678:Viral Structural Proteins; D008156:Luciferases