Effects of the cucumber mosaic virus 2a protein on aphid-plant interactions in Arabidopsis thaliana.
The cucumber mosaic virus has an additional function in Arabidopsis thaliana, which is to stimulate feeding deterrence against aphids
Abstract
The cucumber mosaic virus (CMV) 2a RNA-dependent RNA polymerase protein has an additional function in Arabidopsis thaliana, which is to stimulate feeding deterrence (antixenosis) against aphids. Antixenosis is thought to increase the probability that aphids, after acquiring CMV particles from brief probes of an infected plant’s epidermal cells, will be discouraged from settling and instead will spread inoculum to neighbouring plants. The amino acid sequences of 2a proteins encoded by a CMV strain that induces antixenosis in A. thaliana (Fny-CMV) and one that does not (LS-CMV) were compared to identify residues that might determine the triggering of antixenosis. These data were used to design reassortant viruses comprising Fny-CMV RNAs 1 and 3, and recombinant CMV RNA 2 molecules encoding chimeric 2a proteins containing sequences derived from LS-CMV and Fny-CMV. Antixenosis induction was detected by measuring the mean relative growth rate and fecundity of aphids (Myzus persicae) confined on infected and on mock-inoculated plants. An amino acid sequence determining antixenosis induction by CMV was found to reside between 2a protein residues 200 and 300. Subsequent mutant analysis delineated this to residue 237. We conjecture that the Fny-CMV 2a protein valine-237 plays some role in 2a protein-induced antixenosis.
This is a publication arising from the Sustainable Crop production for International Development (SCPRID) programme.
Citation
Rhee S, Watt L, Bravo A, Murphy A, Carr J (2020). Effects of the cucumber mosaic virus 2a protein on aphid–plant interactions in Arabidopsis thaliana. Molecular Plant Pathology 21: 1248– 1254.
Link
Effects of the cucumber mosaic virus 2a protein on aphid-plant interactions in Arabidopsis thaliana