title: The C-terminal priming domain is strongly associated with the main body of bacteriophage ϕ6 RNA-dependent RNA polymerase.
abstract: Double-stranded RNA viruses encode a single protein species containing RNA-dependent RNA polymerase (RdRP) motifs. This protein is responsible for RNA transcription and replication. The architecture of viral RdRPs resembles that of a cupped right hand with fingers, palm and thumb domains. Those using de novo initiation have a flexible structural elaboration that constitutes the priming platform. Here we investigate the properties of the C-terminal priming domain of bacteriophage ϕ6 to get insights into the role of an extended loop connecting this domain to the main body of the polymerase. Proteolyzed ϕ6 RdRP that possesses a nick in the hinge region of this loop was better suited for de novo initiation. The clipped C-terminus remained associated with the main body of the polymerase via the anchor helix. The structurally flexible hinge region appeared to be involved in the control of priming platform movement. Moreover, we detected abortive initiation products for a bacteriophage RdRP.
authors: Department of Biosciences, University of Helsinki, Biocenter 2, 00014 University of Helsinki, Finland.
authors: L Peter
authors: LP
authors: Sarin
authors: Sam
authors: S
authors: Wright
authors: Qing
authors: Q
authors: Chen
authors: Linda H
authors: LH
authors: Degerth
authors: David I
authors: DI
authors: Stuart
authors: Jonathan M
authors: JM
authors: Grimes
authors: Dennis H
authors: DH
authors: Bamford
authors: Minna M
authors: MM
authors: Poranen
mesh_terms: D017126:Bacteriophage phi 6 / Q000737:chemistry* / Q000201:enzymology*; D008954:Models, Biological; D008958:Models, Molecular; D011485:Protein Binding; D012324:RNA-Dependent RNA Polymerase / Q000737:chemistry* / Q000378:metabolism*; D014158:Transcription, Genetic; D014764:Viral Proteins / Q000737:chemistry* / Q000378:metabolism*; D014779:Virus Replication
chemical_list: D014764:Viral Proteins; D012324:RNA-Dependent RNA Polymerase