The ryegrass mottle virus genome codes for a sobemovirus 3C-like serine protease and RNA-dependent RNA polymerase translated via -1 ribosomal frameshifting.
In the course of sobemovirus gene cloning the complete genome of Ryegrass mottle virus (RGMoV) was sequenced. Sequence analysis revealed differences including missing and extraneous nucleotides in comparison to the previously published sequence (Zhang, Toriyama, Takanashi, J. Gen. Plant Pathol. 67, 63 (2001)). A gene coding for a typical sobemovirus 3C-like serine protease was identified in ORF2a after multiple sequence alignment analysis. The newly identified 57-amino-acid stretch in ORF2a showed similarities ranging from 38.5 to 50.9% among sequenced genes of sobemovirus proteases. ORF analysis of the RGMoV polyprotein coding sequence demonstrated the arrangement of ORF2b coding for RNA-dependent RNA polymerase (RdRP) in the -1 frame in regard to ORF2a. The localization of conserved among sobemoviruses slippery sequence (UUUAAAC) at the 3'-end of ORF2a suggests the translation of RdRP via a -1 ribosomal frameshifting mechanism, allowing to include the RGMoV in the sobemovirus group with a Cocksfoot mottle virus-like (CfMV-like) genome organization.
Balke
Ina
I
Protein Engineering, Latvian Biomedical Research and Study Centre, Ratsupites 1, Riga 1067, Latvia.
Resevica
Gunta
G
Zeltins
Andris
A
D000595:Amino Acid Sequence; D018965:Frameshifting, Ribosomal / Q000235:genetics*; D016679:Genome, Viral; D008129:Lolium / Q000821:virology*; D008969:Molecular Sequence Data; D016366:Open Reading Frames / Q000235:genetics; D010942:Plant Viruses / Q000201:enzymology* / Q000235:genetics*; D014176:Protein Biosynthesis; D012324:RNA-Dependent RNA Polymerase / Q000096:biosynthesis / Q000235:genetics*; D012697:Serine Endopeptidases / Q000096:biosynthesis / Q000235:genetics*; D017361:Viral Nonstructural Proteins / Q000096:biosynthesis / Q000235:genetics
D017361:Viral Nonstructural Proteins; D012324:RNA-Dependent RNA Polymerase; D012697:Serine Endopeptidases