Salicylic acid is an indispensable component of the Ny-1 resistance-gene-mediated response against Potato virus Y infection in potato

Abstract

The purpose of the study was to investigate the role of salicylic acid (SA) signalling in Ny-1-mediated hypersensitive resistance (HR) of potato (Solanum tuberosum L.) to Potato virus Y (PVY). The responses of the Ny-1 allele in the Rywal potato cultivar and transgenic NahG-Rywal potato plants that do not accumulate SA were characterized at the cytological, biochemical, transcriptome, and proteome levels. Analysis of noninoculated and inoculated leaves revealed that HR lesions started to develop from 3 d post inoculation and completely restricted the virus spread. At the cytological level, features of programmed cell death in combination with reactive oxygen species burst were observed. In response to PVY infection, SA was synthesized de novo. The lack of SA accumulation in the NahG plants led to the disease phenotype due to unrestricted viral spreading. Grafting experiments show that SA has a critical role in the inhibition of PVY spreading in parenchymal tissue, but not in vascular veins. The whole transcriptome analysis confirmed the central role of SA in orchestrating Ny-1-mediated responses and showed that the absence of SA leads to significant changes at the transcriptome level, including a delay in activation of expression of genes known to participate in defence responses. Moreover, perturbations in the expression of hormonal signalling genes were detected, shown as a switch from SA to jasmonic acid/ethylene signalling. Viral multiplication in the NahG plants was accompanied by downregulation of photosynthesis genes and activation of multiple energy-producing pathways.

Potato virus Y infection hinders potato defence response and renders plants more vulnerable to Colorado potato beetle attack

“…A positive correlation between SA and GA, and negative feedback between JA/ET and GA in potato after PVY infection was shown previously (Baebler et al . ). A possible mechanism for this action suggested for Arabidopsis is via the DELLA proteins, which are growth repressor proteins that are degraded by a GA‐dependent mechanism (Navarro et al .…”

Review Article: Molecular Mechanisms of Resistance to Potato virus X and Y in Potato

“…In response to PVY infection, SA is synthesised de novo. The whole transcriptome analysis confirmed the central role of SA in orchestrating Ny-1-mediated responses and showed that the absence of SA leads to significant changes at the transcriptome level, including a delay in activation of expression of genes known to participate in defence responses (Baebler et al, 2014).…”

Plant immunity against viruses: antiviral immune receptors in focus

“…The lack of SA accumulation in the NahG potato plants (transgenic lines deficient in SA accumulation) causes unrestricted viral spreading and consequent disease symptoms (Baebler et al, 2014). Transcriptomic analysis confirmed the central role of SA in inducing the Ny-1-mediated responses and showed that the absence of SA leads to significant changes at the gene expression level, including a delay in activation of defence genes.…”

“…The SA defence response is also triggered by Potato virus Y (PVY) and Tomato ringspot virus (ToRSV) (Jovel et al, 2011;Baebler et al, 2014). The lack of SA accumulation in the NahG potato plants (transgenic lines deficient in SA accumulation) causes unrestricted viral spreading and consequent disease symptoms (Baebler et al, 2014).…”