title: Poly(A)- and primer-independent RNA polymerase of Norovirus.
abstract: Replication of positive-strand caliciviruses is mediated by a virus-encoded RNA-dependent RNA polymerase (RdRp). To study the replication of Norovirus (NV), a member of the family Caliciviridae, we used a recombinant baculovirus system to express an enzymatically active RdRp protein from the 3D region of the NV genome and defined conditions for optimum enzymatic activity. Using an RNA template from the NV 3' genomic region, we observed similar levels of enzymatic activity in assays with and without a poly(A) tail. RdRp activity was not significantly affected by the addition of an RNA primer to the reaction mixture. Thus, the NV RdRp exhibited primer- and poly(A)-independent RNA polymerase activity. While the RdRp inhibitor phosphonoacetic acid inhibited NV RdRp activity, another gliotoxin did not. The active recombinant NV RdRp will be of benefit to studies of NV replication and will facilitate the development of specific inhibitors of NV proliferation.
authors.affiliation: R&D Center, BioMedical Laboratories, Kawagoe, Saitama 350-1101, Japan.
authors.forename: Shuetsu
authors.initials: S
authors.lastname: Fukushi
authors.forename: Shigeyuki
authors.initials: S
authors.lastname: Kojima
authors.forename: Reiko
authors.initials: R
authors.lastname: Takai
authors.forename: Fuminori B
authors.initials: FB
authors.lastname: Hoshino
authors.forename: Tomoichiro
authors.initials: T
authors.lastname: Oka
authors.forename: Naokazu
authors.initials: N
authors.lastname: Takeda
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Katayama
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Kageyama
mesh_terms: D000818:Animals; D016367:Baculoviridae / Q000235:genetics; D001483:Base Sequence; D002460:Cell Line; D004279:DNA, Viral / Q000235:genetics; D004791:Enzyme Inhibitors / Q000494:pharmacology; D066298:In Vitro Techniques; D029322:Norovirus / Q000201:enzymology* / Q000235:genetics* / Q000502:physiology; D010746:Phosphonoacetic Acid / Q000494:pharmacology; D012313:RNA / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012367:RNA, Viral / Q000235:genetics / Q000378:metabolism; D012324:RNA-Dependent RNA Polymerase / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism*; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D014779:Virus Replication
chemical_list: D004279:DNA, Viral; D004791:Enzyme Inhibitors; C034477:RNA primers; D012333:RNA, Messenger; D012367:RNA, Viral; D011994:Recombinant Proteins; D012313:RNA; D012324:RNA-Dependent RNA Polymerase; D010746:Phosphonoacetic Acid