RNA-dependent RNA polymerases of dsRNA bacteriophages.
Genome replication and transcription of riboviruses are catalyzed by an RNA-dependent RNA polymerase (RdRP). RdRPs are normally associated with other virus- or/and host-encoded proteins that modulate RNA polymerization activity and template specificity. The polymerase complex of double-stranded dsRNA viruses is a large icosahedral particle (inner core) containing RdRP as a minor constituent. In phi6 and other dsRNA bacteriophages from the Cystoviridae family, the inner core is composed of four virus-specific proteins. Of these, protein P2, or Pol subunit, has been tentatively identified as RdRP by sequence comparisons, but the role of this protein in viral RNA synthesis has not been studied until recently. Here, we overview the work on the Pol subunits of phi6 and related viruses from the standpoints of function, structure and evolution.
Makeyev
Eugene V
EV
Department of Biosciences, Institute of Biotechnology, University of Helsinki, P.O. Box 56, Viikinkaari 5, FIN-00014 Helsinki, Finland. makeyev@mcb.harvard.edu
Grimes
Jonathan M
JM
D000595:Amino Acid Sequence; D017126:Bacteriophage phi 6 / Q000201:enzymology / Q000235:genetics / Q000254:growth & development; D001483:Base Sequence; D017910:Cystoviridae / Q000201:enzymology / Q000235:genetics / Q000254:growth & development; D019143:Evolution, Molecular; D008954:Models, Biological; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011487:Protein Conformation; D012367:RNA, Viral / Q000096:biosynthesis / Q000235:genetics; D012324:RNA-Dependent RNA Polymerase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid; D014158:Transcription, Genetic
D012367:RNA, Viral; D012324:RNA-Dependent RNA Polymerase