Journal of Biological Chemistry · 2004 · 96 citations · 39 references
Life SciencesBiologyMolecular BiologyMolecular VirologyPlant VirologyVirologyPlant Virus ReplicationViral Genome OrganizationViral Protein ProcessingViral ReplicationViral Rna BiologyVirus Genome OrganizationBinding CapacityGenome ReplicationRna Virus BiologyViral PolymerasesViral Polyprotein ProcessingViral Rna Genome OrganizationViral Rna ProcessingViral Rna Synthesis
Poty- and picornaviruses share similar genome organizations and polyprotein processing strategies. By analogy to picornaviruses it has been proposed that the genome-linked protein VPg may serve as a primer for genome replication of potyviruses. The multifunctional VPg of potato virus A (PVA; genus Potyvirus) was found to be uridylylated by NIb, the RNA polymerase of PVA. The nucleotidylation activity of NIb is more efficient in the presence of Mn(2+) than Mg(2+) and does not require an RNA template. Our results suggest that the nucleotidylation reaction exhibits weak preference for UTP over the other NTPs. An NTP-binding experiment with oxidized [alpha-(32)P]UTP revealed that PVA VPg contains an NTP-binding site. Deletion of a 7-amino acid-long putative NTP-binding site from VPg reduced nucleotide-binding capacity and debilitated uridylylation reaction. These results provide evidence that VPg may play a similar role in RNA synthesis of potyviruses as it does in the case of picornaviruses.
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A mechanism for initiating RNA-dependent RNA polymerization
Sarah J. Butcher, Jonathan M. Grimes, Eugene V. Makeyev et al. · Nature · 2001 · 491 citations
Protein-primed RNA synthesis by purified poliovirus RNA polymerase
Aniko V. Paul, Jacques H. van Boom, Dmitri V. Filippov et al. · Nature · 1998 · 378 citations