Differential responses to virus challenge of laboratory and wild accessions of australian species of nicotiana, and comparative analysis of RDR1 gene sequences

PLoS One. 2015 Mar 30;10(3):e0121787. doi: 10.1371/journal.pone.0121787. eCollection 2015.

Abstract

Nicotiana benthamiana is a model plant utilised internationally in plant virology because of its apparent hyper-susceptibility to virus infection. Previously, others showed that all laboratory accessions of N. benthamiana have a very narrow genetic basis, probably originating from a single source. It is unknown if responses to virus infection exhibited by the laboratory accession are typical of the species as a whole. To test this, 23 accessions of N. benthamiana were collected from wild populations and challenged with one to four viruses. Additionally, accessions of 21 other Nicotiana species and subspecies from Australia, one from Peru and one from Namibia were tested for susceptibility to the viruses, and for the presence of a mutated RNA-dependent RNA polymerase I allele (Nb-RDR1m) described previously from a laboratory accession of N. benthamiana. All Australian Nicotiana accessions tested were susceptible to virus infections, although there was symptom variability within and between species. The most striking difference was that plants of a laboratory accession of N. benthamiana (RA-4) exhibited hypersensitivity to Yellow tailflower mild mottle tobamovirus infection and died, whereas plants of wild N. benthamiana accessions responded with non-necrotic symptoms. Plants of certain N. occidentalis accessions also exhibited initial hypersensitivity to Yellow tailflower mild mottle virus resembling that of N. benthamiana RA-4 plants, but later recovered. The mutant Nb-RDR1m allele was identified from N. benthamiana RA-4 but not from any of 51 other Nicotiana accessions, including wild accessions of N. benthamiana, demonstrating that the accession of N. benthamiana used widely in laboratories is unusual.

Publication types

  • Comparative Study

MeSH terms

  • Australia
  • Cucumovirus / pathogenicity
  • Genes, Plant*
  • Genetic Predisposition to Disease
  • Molecular Sequence Data
  • Mutation
  • Nicotiana / classification
  • Nicotiana / genetics*
  • Nicotiana / virology*
  • Plant Diseases / genetics
  • Plant Diseases / virology
  • Plant Proteins / genetics*
  • Potyvirus / pathogenicity
  • RNA-Dependent RNA Polymerase / genetics*
  • Species Specificity
  • Tobamovirus / pathogenicity
  • Tospovirus / pathogenicity

Substances

  • Plant Proteins
  • RNA-Dependent RNA Polymerase

Associated data

  • GENBANK/KM411303
  • GENBANK/KM411304
  • GENBANK/KM411305
  • GENBANK/KM411306
  • GENBANK/KM411307
  • GENBANK/KM411308
  • GENBANK/KM411309
  • GENBANK/KM411310
  • GENBANK/KM411311
  • GENBANK/KM411312
  • GENBANK/KM411313
  • GENBANK/KM411314
  • GENBANK/KM411315
  • GENBANK/KM411316
  • GENBANK/KM411317
  • GENBANK/KM411318
  • GENBANK/KM411319
  • GENBANK/KM411320
  • GENBANK/KM411321
  • GENBANK/KM411322
  • GENBANK/KM411323
  • GENBANK/KM411324
  • GENBANK/KM411325
  • GENBANK/KM411326
  • GENBANK/KM411327
  • GENBANK/KM411328
  • GENBANK/KM411329
  • GENBANK/KM411330
  • GENBANK/KM411331
  • GENBANK/KM411332
  • GENBANK/KM411333
  • GENBANK/KM411334
  • GENBANK/KM411335
  • GENBANK/KM411336
  • GENBANK/KM411337
  • GENBANK/KM411338
  • GENBANK/KM411339
  • GENBANK/KM411340
  • GENBANK/KM411341
  • GENBANK/KM411342
  • GENBANK/KM411343
  • GENBANK/KM411344
  • GENBANK/KM411345
  • GENBANK/KM411346
  • GENBANK/KM411347
  • GENBANK/KM411348
  • GENBANK/KM411349
  • GENBANK/KM411350
  • GENBANK/KM411351
  • GENBANK/KM411352
  • GENBANK/KM411353

Grants and funding

Murdoch University provided MJR with an adjunct professorial position and scholarship to collect the plant samples described here. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.