Plant Science, Agronomy and Crop Science, Agricultural and Biological Sciences, General Agricultural and Biological Sciences
2
Scopus Publications
Scopus Publications
The CAPE1 peptide confers resistance against bacterial wilt in tomato Weiqi Zhang, Marc Planas-Marquès, Moyan Liang, Qingshan Zhang, Annemarie Vermeulen, Farnusch Kaschani, Markus Kaiser, Frank L W Takken, Nuria S Coll, Marc Valls Journal of Experimental Botany, 2025 Bacterial wilt caused by Ralstonia solanacearum is one of the most destructive bacterial diseases for which no effective treatment exists. There is an urgent need to understand the basis of resistance against this pathogen in order to engineer efficient strategies in the field. We previously demonstrated that resistant tomato plants limit bacterial movement in the apoplast and the xylem. As a first step to dissect the underlying mechanisms, we analysed the apoplast proteome upon challenge with R. solanacearum in the susceptible tomato cultivar Marmande and the resistant cultivar Hawaii 7996. Here, we described the xylem proteome in these same cultivars and compared it with the apoplastic proteome, revealing variety-dependent and infection-dependent changes. This proteomic analysis led to the identification of pathogenesis-related 1 (PR1) proteins as highly induced upon infection. Since PR1b was the most abundant PR1 protein in both the apoplast and the xylem, we concentrated on this family member to study the role of PR1s in the interaction between tomato and R. solanacearum. Surprisingly, lack of PR1b resulted in enhanced resistance to R. solanacearum in tomato, which could be due to an up-regulation of homologous genes in a compensatory effect as has been reported before. PR1 processing by an unknown protease in tomato results in the generation of the CAPE peptide. Treatment of tomato plants with the CAPE1 peptide resulted in restriction of R. solanacearum growth, via defence gene reprogramming. Future work in the lab will help determine which tomato secreted proteases cleave PR1s to generate CAPEs.
The Tomato PR-5 Proteins PR-5x and NP24 Exert Antifungal Activity Against Fusarium oxysporum Margarita Šimkovicová, Alicia Invernón Garrido, Ilse A. W. Bakker, Bas Beerens, Moyan Liang, Martijn Rep, Núria S. Coll, Marc Valls, Frank L. W. Takken Plant Pathology, 2025 Vascular wilt diseases, caused by the soilborne pathogen Fusarium oxysporum (Fo), significantly impact agriculture and horticulture. Traditional management strategies are often environmentally harmful and not effective once the pathogen has entered the host. Consequently, understanding the molecular mechanisms underlying resistance to pathogenic Fo strains is crucial for developing novel control strategies. In tomato, resistance to F. oxysporum f. sp. lycopersici (Fol) can be mediated by R genes, such as I‐1 , I‐2 or I‐3 , or by Fo endophytes. Fol inoculation of resistant lines results in high accumulation of pathogenesis‐related 5 (PR‐5) proteins. However, the role of xylem‐localised PR‐5 proteins in Fol resistance in tomato plants remains unknown. Here, we demonstrate that apoplastic fluid enriched with recombinant PR‐5x or NP24 exhibits antifungal activity against Fol. Using CRISPR/Cas9‐mediated gene editing and overexpression studies, the role of PR‐5x and NP24 in disease resistance was studied. Loss‐of‐function mutations in either PR‐5 isoform did not compromise Fol resistance. However, overexpression of NP24 in tomato plants resulted in decreased susceptibility to Fol and surprisingly enhanced susceptibility to Ralstonia solanacearum . The role of PR‐5x in Fol resistance remains undetermined as lines overexpressing the transgene could not be identified. Our findings suggest that PR‐5 proteins are involved in restricting Fol proliferation in the xylem vasculature and thereby contribute to disease resistance.
