title: Role of the influenza virus heterotrimeric RNA polymerase complex in the initiation of replication.
abstract: Both transcription and replication of the influenza virus RNA genome are catalysed by a virus-specific RNA polymerase. Recently, an in vitro assay, based on the synthesis of pppApG, for the initiation of replication by recombinant RNA polymerase in the absence of added primer was described. Here, these findings are extended to show that adenosine, AMP and ADP can each substitute for ATP in reactions catalysed by either recombinant ribonucleoprotein or RNA polymerase complexes with either model virion RNA (vRNA) or cRNA promoters. The use of either adenosine or AMP, rather than ATP, provides a convenient, sensitive and easy assay of replication initiation. Moreover, no pppApG was detected when a PB1-PA dimer, rather than the trimeric polymerase, was used to catalyse synthesis, contrasting with a previous report using baculovirus-expressed influenza RNA polymerase. Overall, it is suggested that the heterotrimeric polymerase is essential for the initiation of replication.
authors.affiliation: Sir William Dunn School of Pathology, Chemical Pathology Unit, University of Oxford, South Parks Road, Oxford, OX1 3RE, UK.
authors.forename: Tao
authors.initials: T
authors.lastname: Deng
authors.affiliation: Sir William Dunn School of Pathology, Chemical Pathology Unit, University of Oxford, South Parks Road, Oxford, OX1 3RE, UK.
authors.forename: Jane L
authors.initials: JL
authors.lastname: Sharps
authors.affiliation: Sir William Dunn School of Pathology, Chemical Pathology Unit, University of Oxford, South Parks Road, Oxford, OX1 3RE, UK.
authors.forename: George G
authors.initials: GG
authors.lastname: Brownlee
mesh_terms: D000241:Adenosine / Q000502:physiology; D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate / Q000502:physiology; D002460:Cell Line; D012321:DNA-Directed RNA Polymerases / Q000737:chemistry / Q000378:metabolism*; D019281:Dimerization; D006801:Humans; D009690:Nucleic Acid Conformation; D009975:Orthomyxoviridae / Q000502:physiology*; D011401:Promoter Regions, Genetic / Q000235:genetics / Q000502:physiology; D021122:Protein Subunits / Q000378:metabolism; D018075:RNA, Complementary / Q000235:genetics / Q000378:metabolism; D012367:RNA, Viral / Q000235:genetics / Q000378:metabolism; D012324:RNA-Dependent RNA Polymerase / Q000378:metabolism; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000378:metabolism; D012261:Ribonucleoproteins / Q000235:genetics / Q000378:metabolism; D014764:Viral Proteins / Q000378:metabolism; D014779:Virus Replication
chemical_list: C061290:PA protein, influenza viruses; C502893:PB2 protein, influenza virus; D021122:Protein Subunits; D018075:RNA, Complementary; D012367:RNA, Viral; D011994:Recombinant Proteins; D012261:Ribonucleoproteins; D014764:Viral Proteins; C077346:influenza virus polymerase basic protein 1; D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate; D012324:RNA-Dependent RNA Polymerase; D012321:DNA-Directed RNA Polymerases; D000241:Adenosine