Secretome Analysis of Arabidopsis–Trichoderma atroviride Interaction Unveils New Roles for the Plant Glutamate:Glyoxylate Aminotransferase GGAT1 in Plant Growth Induced by the Fungus and Resistance against Botrytis cinerea

Abstract

The establishment of plant–fungus mutualistic interaction requires bidirectional molecular crosstalk. Therefore, the analysis of the interacting organisms secretomes would help to understand how such relationships are established. Here, a gel-free shotgun proteomics approach was used to identify the secreted proteins of the plant Arabidopsis thaliana and the mutualistic fungus Trichoderma atroviride during their interaction. A total of 126 proteins of Arabidopsis and 1027 of T. atroviride were identified. Among them, 118 and 780 were differentially modulated, respectively. Bioinformatic analysis unveiled that both organisms’ secretomes were enriched with enzymes. In T. atroviride, glycosidases, aspartic endopeptidases, and dehydrogenases increased in response to Arabidopsis. Additionally, amidases, protein-serine/threonine kinases, and hydro-lyases showed decreased levels. Furthermore, peroxidases, cysteine endopeptidases, and enzymes related to the catabolism of secondary metabolites increased in the plant secretome. In contrast, pathogenesis-related proteins and protease inhibitors decreased in response to the fungus. Notably, the glutamate:glyoxylate aminotransferase GGAT1 was secreted by Arabidopsis during its interaction with T. atroviride. Our study showed that GGAT1 is partially required for plant growth stimulation and on the induction of the plant systemic resistance by T. atroviride. Additionally, GGAT1 seems to participate in the negative regulation of the plant systemic resistance against B. cinerea through a mechanism involving H2O2 production.

Insights into the ecological generalist lifestyle of Clonostachys fungi through analysis of their predicted secretomes

“…upon contact with the plant hosts Phaseolus vulgaris and Arabidopsis thaliana , and Clonostachys spp. might behave similarly ( González-López et al, 2021 ; da Silva et al, 2022 ). Alternatively, these genomic adaptations may indicate a greater capacity for saprophytic growth of Clonostachys spp., which may also influence its usefulness in biocontrol applications.…”

Comparative Secretome Analyses of Trichoderma/Arabidopsis Co-cultures Identify Proteins for Salt Stress, Plant Growth Promotion, and Root Colonization

“…Numerous studies investigated the Trichoderma secretome in symbiotic interactions with hosts (e.g., Gómez-Mendoza et al, 2014;Lamdan et al, 2015;González-López et al, 2021;Zhao et al, 2021). Besides similarities in the protein patterns and their interpretation (cf.…”

Molecular interaction between plants and Trichoderma species against soil-borne plant pathogens

“…The gene most preferentially expressed in T. virens during its interaction with tomato was revealed to be a secreted quino-protein, glucose dehydrogenase. Several studies on the secretome of different species of Trichoderma co-cultured with plants have reported an increased expression of genes encoding glycosidases and peptidases during the initial phase of their interaction ( Lamdan et al., 2015 ; González-López et al., 2021 ). Reduction in tomato root colonization by a T. harzianum mutant with a silenced thpg1 gene encoding endopolygalactouronase indicates the probable role of fungal glycosidases and peptidases in plant– Trichoderma interactions.…”