Dual Transcriptome and Metabolic Analysis of Vitis vinifera cv. Pinot Noir Berry and Botrytis cinerea During Quiescence and Egressed Infection

Abstract

Botrytis cinerea is an important necrotroph in vineyards. Primary infections are mostly initiated by airborne conidia from overwintered sources around bloom, then the fungus remains quiescent from bloom till maturity and egresses at ripeness. We previously described in detail the process of flower infection and quiescence initiation. Here, we complete the characterization studying the cross-talk between the plant and the fungus during pathogen quiescence and egression by an integrated transcriptomic and metabolic analysis of the host and the pathogen. Flowers from fruiting cuttings of the cv. Pinot Noir were inoculated with a GFP-labeled strain of B. cinerea at full cap-off stage, and molecular analyses were carried out at 4 weeks post inoculation (wpi, fungal quiescent state) and at 12 wpi (fungal pre-egression and egression states). The expressed fungal transcriptome highlighted that the fungus remodels its cell wall to evade plant chitinases besides undergoing basal metabolic activities. Berries responded by differentially regulating genes encoding for different PR proteins and genes involved in monolignol, flavonoid, and stilbenoid biosynthesis pathways. At 12 wpi, the transcriptome of B. cinerea in the pre-egressed samples showed that virulence-related genes were expressed, suggesting infection process was initiated. The egressed B. cinerea expressed almost all virulence and growth related genes that enabled the pathogen to colonize the berries. In response to egression, ripe berries reprogrammed different defense responses, though futile. Examples are activation of membrane localized kinases, stilbene synthases, and other PR proteins related to SA and JA-mediated responses. Our results indicated that hard-

Botrytis cinerea Transcriptome during the Infection Process of the Bryophyte Physcomitrium patens and Angiosperms

“…Transcriptional profiling during the B. cinerea infection process has been performed in several angiosperms [ 38 , 39 , 40 , 48 , 49 , 50 , 51 ]. However, no information related to the molecular mechanisms used by B. cinerea during moss invasion is available.…”

Proanthocyanidins and Where to Find Them: A Meta-Analytic Approach to Investigate Their Chemistry, Biosynthesis, Distribution, and Effect on Human Health

“…However, PACs have also been shown effective against fungi infection. Indeed, several experimental studies have reported that after the inoculation of different fungal strains, the plants increased the biosynthesis of PACs, causing a reduction, and in some cases the complete eradication, of the infection [ 71 , 72 , 73 , 74 , 75 , 76 , 77 , 78 ]. Similar phenomena were also observed during insect attack [ 79 , 80 ].…”

Transcriptome Analysis of the Fruit of Two Strawberry Cultivars “Sunnyberry” and “Kingsberry” That Show Different Susceptibility to Botrytis cinerea after Harvest

“…Certain studies have compared the transcriptomes of resistant and sensitive cultivars in the absence of pathogen attack [ 20 , 21 ]. Other studies have compared defense responses between unripe and ripe fruits because B. cinerea is quiescent in green fruit [ 22 , 23 , 24 ].…”