Profiling Plant Proteome and Transcriptome Changes during Grapevine Fanleaf Virus Infection

Viruses can elicit
varying types and severities of symptoms during
plant host infection. We investigated changes in the proteome and
transcriptome of Nicotiana benthamiana plants infected by grapevine fanleaf virus (GFLV) with an emphasis
on vein clearing symptom development. Comparative, time-course liquid
chromatography tandem mass spectrometry and 3′ ribonucleic
acid sequencing analyses of plants infected by two wildtype GFLV strains,
one symptomatic and one asymptomatic, and their asymptomatic mutant
strains carrying a single amino acid change in the RNA-dependent RNA
polymerase (RdRP) were conducted to identify host biochemical pathways
involved in viral symptom development. During peak vein clearing symptom
display at 7 days post-inoculation (dpi), protein and gene ontologies
related to immune response, gene regulation, and secondary metabolite
production were overrepresented when contrasting wildtype GFLV strain
GHu and mutant GHu-1EK802GPol. Prior to the
onset of symptom development at 4 dpi and when symptoms faded away
at 12 dpi, protein and gene ontologies related to chitinase activity,
hypersensitive response, and transcriptional regulation were identified.
This systems biology approach highlighted how a single amino acid
of a plant viral RdRP mediates changes to the host proteome (∼1%)
and transcriptome (∼8.5%) related to transient vein clearing
symptoms and the network of pathways involved in the virus–host
arms race.