Proteomic analysis of the phytopathogenic soilborne fungusVerticillium dahliaereveals differential protein expression in isolates that differ in aggressiveness

Abstract

Verticillium dahliae is a soilborne fungus that causes a vascular wilt disease of plants and losses in a broad range of economically important crops worldwide. In this study, we compared the proteomes of highly (Vd1396-9) and weakly (Vs06-14) aggressive isolates of V. dahliae to identify protein factors that may contribute to pathogenicity. Twenty-five protein spots were consistently observed as differential in the proteome profiles of the two isolates. The protein sequences in the spots were identified by LC-ESI-MS/MS and MASCOT database searches. Some of the identified sequences shared homology with fungal proteins that have roles in stress response, colonization, melanin biosynthesis, microsclerotia formation, antibiotic resistance, and fungal penetration. These are important functions for infection of the host and survival of the pathogen in soil. One protein found only in the highly aggressive isolate was identified as isochorismatase hydrolase, a potential plant-defense suppressor. This enzyme may inhibit the production of salicylic acid, which is important for plant defense response signaling. Other sequences corresponding to potential pathogenicity factors were identified in the highly aggressive isolate. This work indicates that, in combination with functional genomics, proteomics-based analyses can provide additional insights into pathogenesis and potential management strategies for this disease.

Overexpression of StRbohA in Arabidopsis thaliana enhances defence responses against Verticillium dahliae

“…For example, it is intriguing that the isolates that were deemed highly (Vs 06-14) and weakly (Vd1396-9) aggressive on Arabidopsis in this study did exactly the opposite on potato and sunflower [36]. The effects of these isolates as observed on potato and sunflower were not an artefact, since such results were verified in other previous experiments [29,32,36,46]. In addition, the results we obtained on Arabidopsis are similar to those we had on canola (results not shown), which is a close relative to Arabidopsis.…”

“…Many of our recent studies that used proteomic [29], metabolomic [30,31] and transcriptomic approaches [32,33] to investigate the mechanisms underlying V. dahliae virulence, evoked the importance of ROS in host-V. dahliae interactions. Thus, better understanding of the role of ROS in such mechanisms is an important step towards developing sustainable solutions for verticillium and other wilts.…”

Verticillium wilts in crop plants: Pathogen invasion and host defence responses

“…The task becomes even more complex when such variability is combined with the pathogen's strong responsiveness to environmental clues, resulting in an even more diverse population of the pathogen. The diversity of V. dahliae has been extensively studied, using strains from different crops and origins, and covering everything from morphology to several 'omics' in describing V. dahliae strains (Klosterman et al 2009;El-Bebany et al 2010, 2011. Most studies made an effort to link genetic diversity markers with phenotypes such as pathogenicity, virulence, and vegetative compatibility (Daayf et al 1995;Alkher et al 2009aAlkher et al , 2009bEl-Bebany et al 2013b).…”

Genetic diversity ofVerticillium dahliaefrom olive trees in Tunisia based on RAMS and IGS-RFLP analyses

“…Useful information on the diversity of V. dahliae populations has been provided by vegetative compatibility groupings (VCG), especially when combined with pathogenicity studies (Daayf et al 1995;Dobinson et al 2000;Korolev et al 2008;Alkher et al 2009). However, understanding the complex population structure of this fungus and its ability to infect different crops cannot be achieved using these techniques alone and usually requires further molecular analysis (El-Bebany et al 2010.…”