title: An efficient viral vector for functional genomic studies of Prunus fruit trees and its induced resistance to Plum pox virus via silencing of a host factor gene.
abstract: RNA silencing is a powerful technology for molecular characterization of gene functions in plants. A commonly used approach to the induction of RNA silencing is through genetic transformation. A potent alternative is to use a modified viral vector for virus-induced gene silencing (VIGS) to degrade RNA molecules sharing similar nucleotide sequence. Unfortunately, genomic studies in many allogamous woody perennials such as peach are severely hindered because they have a long juvenile period and are recalcitrant to genetic transformation. Here, we report the development of a viral vector derived from Prunus necrotic ringspot virus (PNRSV), a widespread fruit tree virus that is endemic in all Prunus fruit production countries and regions in the world. We show that the modified PNRSV vector, harbouring the sense-orientated target gene sequence of 100-200 bp in length in genomic RNA3, could efficiently trigger the silencing of a transgene or an endogenous gene in the model plant Nicotiana benthamiana. We further demonstrate that the PNRSV-based vector could be manipulated to silence endogenous genes in peach such as eukaryotic translation initiation factor 4E isoform (eIF(iso)4E), a host factor of many potyviruses including Plum pox virus (PPV). Moreover, the eIF(iso)4E-knocked down peach plants were resistant to PPV. This work opens a potential avenue for the control of virus diseases in perennial trees via viral vector-mediated silencing of host factors, and the PNRSV vector may serve as a powerful molecular tool for functional genomic studies of Prunus fruit trees.
authors: London Research and Development Centre, Agriculture and Agri-Food Canada (AAFC), London, ON, Canada.
authors: Hongguang
authors: H
authors: Cui
authors: London Research and Development Centre, Agriculture and Agri-Food Canada (AAFC), London, ON, Canada.
authors: Aiming
authors: A
authors: Wang
mesh_terms: D060467:Disease Resistance / Q000235:genetics; D018745:Genome, Plant / Q000235:genetics*; D010935:Plant Diseases / Q000235:genetics* / Q000821:virology*; D010940:Plant Proteins / Q000235:genetics; D030821:Plants, Genetically Modified / Q000235:genetics* / Q000821:virology*; D017801:Plum Pox Virus / Q000472:pathogenicity*; D027861:Prunus / Q000235:genetics* / Q000821:virology*; D034622:RNA Interference
chemical_list: D010940:Plant Proteins
keywords: 
  Prunus necrotic ringspot virus
  ; 
  eukaryotic translation initiation factor 4E
  ; functional genomics; sharka; viral vector; virus-induced gene silencing