RNA duplex unwinding activity of alfalfa mosaic virus RNA-dependent RNA polymerase.
An RNA-dependent RNA polymerase (RdRp) purified from alfalfa mosaic virus-infected tobacco is capable of synthesizing in vitro full-size RNAs of minus and plus polarities. However, the enzyme is not able to perform a complete replication cycle in vitro. The products were found to be completely base-paired to their templates. The enzyme was able to use double-stranded RNA as a template for RNA synthesis if it could initiate from a single-stranded promoter. The inability (of most) of our enzyme preparations to create a single-stranded initiation site could explain why they could not perform a complete replication cycle in vitro. This is the first report on duplex RNA unwinding activities by a plant viral RdRp.
de Graaff
M
M
Institute of Molecular Plant Sciences, Leiden University, The Netherlands.
Houwing
C J
CJ
Lukács
N
N
Jaspars
E M
EM
D017794:Alfalfa mosaic virus / Q000201:enzymology*; D012330:RNA, Double-Stranded / Q000378:metabolism; D012367:RNA, Viral / Q000378:metabolism*; D012324:RNA-Dependent RNA Polymerase / Q000378:metabolism*
D012330:RNA, Double-Stranded; D012367:RNA, Viral; D012324:RNA-Dependent RNA Polymerase