Prunus persica plant endogenous peptides PpPep1 and PpPep2 cause PTI-like transcriptome reprogramming in peach and enhance resistance to Xanthomonas arboricola pv. pruni

Abstract

Background Rosaceae species are economically highly relevant crops. Their cultivation systems are constrained by phytopathogens causing severe losses. Plants respond to invading pathogens through signaling mechanisms, a component of which are of them being plant elicitor peptides (Peps). Exogenous application of Peps activates defense mechanisms and reduces the symptoms of pathogen infection in various pathosystems. We have previously identified the Rosaceae Peps and showed, in an ex vivo system, that their topical application efficiently enhanced resistance to the bacterial pathogen Xanthomonas arboricola pv. pruni (Xap). Results Here we demonstrate the effectiveness of Prunus persica peptides PpPep1 and PpPep2 in protecting peach plants in vivo at nanomolar doses, with 40% reduction of the symptoms following Xap massive infection. We used deep sequencing to characterize the transcriptomic response of peach plants to preventive treatment with PpPep1 and PpPep2. The two peptides induced highly similar massive transcriptomic reprogramming in the plant. One hour, 1 day and 2 days after peptide application there were changes in expression in up to 8% of peach genes. We visualized the transcriptomics dynamics in a background knowledge network and detected the minor variations between plant responses to PpPep1 and PpPep2, which might explain their slightly different protective effects. By designing a P. persica Pep background knowledge network, comparison of our data and previously published immune response datasets was possible. Conclusions Topical application of P. persica Peps mimics the PTI natural response and protects plants against massive Xap infection. This makes them good candidates for deployment of natural, targeted and environmental-friendly strategies to enhance resistance in Prunus species and prevent important biotic diseases.

BoPEP4, a C-Terminally Encoded Plant Elicitor Peptide from Broccoli, Plays a Role in Salinity Stress Tolerance

“…Youxiu) sprouts showed severe salt damage when the NaCl concentration was increased to 200 mM ( Figure S3 ). Similarly to previous reports [ 18 ], we found BoPep4 treatment triggered significant seedling growth inhibition in a concentration-dependent manner, with the minimum inhibition achieved at 100 nM doses ( Figure S4 ). Thus, 100 nM BoPep4 pretreatment followed by 200 mM NaCl treatment was selected for further experiments.…”

“…We observed extensive transcriptional reprogramming of broccoli roots under salinity treatment (NR), as well as combination treatment of BoPep4 with NaCl (PR) compared with the mock control (CR) ( Figure 4 and Table S4 ). There were a variety of DEGs enriched in “plant–pathogen interaction” and “MAPK signaling” pathways ( Figure 4 ), which is consistent with the view established in Arabidopsis and peach that Pep induced major regulation in activation of pattern-triggered immunity (PTI) signaling [ 5 , 18 ]. Pep perception contributing to defense responses depends on the corresponding receptor PEPRs in Arabidopsis [ 8 ].…”

“…It is well known that plant hormones play a critical role in the entire plant’s growth period, especially when surviving in an adverse environment. Pep-induced systemic immune response was described to be related to ethylene (ET), salicylic acid (SA) and jasmonic acid (JA) signal transduction [ 16 , 18 , 31 , 38 ]. In the current study, DEGs related to hormone signaling, with special significance of auxin and ABA hormone signal transduction, were detected.…”

“…Moreover, the presence and pathogen defense activity of Peps within Rosaceae was characterized in [ 17 ]. Prunus persica peptides PpPep1 and PpPep2 were proved to cause PTI-like transcriptome reprogramming at nanomolar doses in vivo [ 18 ]. Interestingly, GmPep914, a novel peptide isolated from soybean leaves, was capable of alkalinizing the media of soybean suspension cells and inducing the expression of genes involved in pathogen defense and phytoalexin production [ 19 ].…”

Bactericidal and plant defense elicitation activities of Eucalyptus oil decrease the severity of infections by Xylella fastidiosa on almond plants

“…RNA samples of 3 plants were pooled in the same Eppendorf tube, and three biological replicates per treatment were analyzed (9 plants/treatment, 3 tubes per treatment). cDNA was synthesized from RNA samples using High-Capacity cDNA Reverse Transcription Kits (Thermo Fisher Scientific Inc.) and was assayed for quantify the expression levels of eight Prunu s genes related to plant defense and previously described in Ruiz et al (2017) ; Tong et al (2009) ; Foix et al. (2021) .…”