Mutations in the coat protein-binding cis-acting RNA motifs debilitate RNA recombination of Brome mosaic virus.
We have previously described the efficient homologous recombination system between 5' subgenomic RNA3a (sgRNA3a) and genomic RNA3 of Brome mosaic virus (BMV) in barley protoplasts (Sztuba-Solińska et al., 2011a). Here, we demonstrated that sequence alterations in the coat protein (CP)-binding cis-acting RNA motifs, the Bbox region (in the intercistronic RNA3 sequence) and the RNA3 packaging element (PE, in the movement protein ORF), reduced crossover frequencies in protoplasts. Additionally, the modification of Bbox-like element in the 5' UTR region strongly debilitated crossovers. Along the lines of these observations, RNA3 mutants not expressing CP or expressing mutated CPs also reduced recombination. A series of reciprocal transfections demonstrated a functional crosstalk between the Bbox and PE elements. Altogether, our data imply the role of CP in sgRNA3a-directed recombination by either facilitating the interaction of the RNA substrates and/or by creating roadblocks for the viral replicase.
Plant Molecular Biology Center and the Department of Biological Sciences, Northern Illinois University, DeKalb, IL 60115, USA.
Joanna
J
Sztuba-Solińska
Sean W
SW
Fanning
James R
JR
Horn
Jozef J
JJ
Bujarski
D020121:5' Untranslated Regions; D001483:Base Sequence; D017795:Bromovirus / Q000235:genetics*; D036022:Capsid Proteins / Q000235:genetics*; D023061:Gene Order; D016679:Genome, Viral; D008969:Molecular Sequence Data; D009154:Mutation; D009690:Nucleic Acid Conformation; D059372:Nucleotide Motifs; D016366:Open Reading Frames; D011485:Protein Binding; D011523:Protoplasts / Q000378:metabolism; D020871:RNA Stability; D012367:RNA, Viral / Q000235:genetics* / Q000378:metabolism; D011995:Recombination, Genetic; D012045:Regulatory Sequences, Nucleic Acid; D014162:Transfection
D020121:5' Untranslated Regions; D036022:Capsid Proteins; D012367:RNA, Viral