Initiation of minus-strand RNA synthesis by the brome mosaicvirus RNA-dependent RNA polymerase: use of oligoribonucleotide primers.
Various DNA- and RNA-dependent RNA polymerases have been reported to use oligoribonucleotide primers to initiate nucleic acid synthesis. For the brome mosaic virus RNA-dependent RNA polymerase (RdRp), we determined that in reactions performed with limited GTP concentrations, minus-strand RNA synthesis can be stimulated by the inclusion of guanosine monophosphate or specific oligoribonucleotides. Furthermore, guanylyl-3',5'-guanosine (GpG) was incorporated into minus-strand RNA and increased the rate of minus-strand RNA synthesis. In the presence of GpG, RdRp's Km for GTP decreased from 50 microM to approximately 3 microM while the Kms for other nucleotides were unaffected. These results have implications for the mechanism of initiation by RdRp.
Kao
C C
CC
Department of Biology, Indiana University, Bloomington 47405, USA.
Sun
J H
JH
D017795:Bromovirus / Q000201:enzymology / Q000235:genetics*; D017931:DNA Primers; D012321:DNA-Directed RNA Polymerases / Q000378:metabolism*; D012367:RNA, Viral / Q000096:biosynthesis* / Q000235:genetics
D017931:DNA Primers; D012367:RNA, Viral; D012321:DNA-Directed RNA Polymerases