IPA-1 a Putative Chromatin Remodeler/Helicase-Related Protein of Trichoderma virens Plays Important Roles in Antibiosis Against Rhizoctonia solani and Induction of Arabidopsis Systemic Disease Resistance

Abstract

Trichoderma spp. are filamentous fungi that colonize plant roots conferring beneficial effects to plants, either indirectly through the induction of their defense systems or directly through the suppression of phytopathogens in the rhizosphere. Transcriptomic analyses of Trichoderma spp. emerged as a powerful method for identifying the molecular events underlying the establishment of this beneficial relationship. Here, we focus on the transcriptomic response of Trichoderma virens during its interaction with Arabidopsis seedlings. The main response of T. virens to cocultivation with Arabidopsis was the repression of gene expression. The biological processes of transport and metabolism of carbohydrates were downregulated, including a set of cell wall–degrading enzymes putatively relevant for root colonization. Repression of such genes reached their basal levels at later times in the interaction, when genes belonging to the biological process of copper ion transport were induced, a necessary process providing copper as a cofactor for cell wall–degrading enzymes with the auxiliary activities class. RNA-Seq analyses showed the induction of a member of the SNF2 family of chromatin remodelers/helicase-related proteins, which was named IPA-1 (increased protection of Arabidopsis-1). Sequence analyses of IPA-1 showed its closest relatives to be members of the Rad5/Rad16 and SNF2 subfamilies; however, it grouped into a different clade. Although deletion of IPA-1 in T. virens did not affect its growth, the antibiotic activity of Δipa-1 culture filtrates against Rhizoctonia solani diminished but it remained unaltered against Botrytis cinerea. Triggering of the plant defense genes in plants treated with Δipa-1 was higher, showing enhanced resistance against Pseudomonas syringae but not against B. cinerea as compared with the wild type.

Inferring co-expression networks of Arabidopsis thaliana genes during their interaction with Trichoderma spp.

“…A. thaliana seeds were germinated in Murashige and Skoog medium [1x] containing 10% sucrose (PhytoTechnology Laboratories, USA). Subsequently, the seeds were incubated for ≈12 days at 22 ± 1 °C with a regime of 16 h of light and 8 h of darkness 49 .…”

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

“…10 [89] were routinely grown at 28 • C on potato dextrose agar (PDA) (DIFCO) for 7 and 14 days, respectively. T. atroviride conidia were collected with sterile distilled water and adjusted at 1 × 10 6 mL −1 , whereas B. cinerea conidia were adjusted to 5 × 10 5 mL −1 in inoculation buffer (per 40 mL of stock solution: Sucrose 1.37 g, 1 M KH 2 PO 4 400 µL, 12.5% Tween20: 80 µL) [90].…”

A potential role of salicylic acid in the evolutionary behavior of Trichoderma as a plant pathogen: from Marchantia polymorpha to Arabidopsis thaliana

“…Trichoderma is a genus of filamentous fungi that includes several widely studied species, some of which have been used as biological control agents due to their easy adaptation to diverse climatic and edaphic conditions and their different mechanisms of action. Trichoderma can protect the plant against different pathogens through mechanisms such as mycoparasitism (Guzmán-Guzmán et al 2019 ), antibiosis (Estrada-Rivera et al 2020 ) and competition with the pathogen for space, specific sites of infection and growth factors (Vinale et al 2008 ). Likewise, the establishment of a Trichoderma -plant symbiotic relationship provides a series of indirect benefits such as the promotion of plant growth (Benítez et al 2004 ; Contreras-Cornejo et al 2018 ), increased tolerance against abiotic (Kashyap et al 2017 ; Poveda 2020b ) and biotic stresses caused by fungal pathogens (Poveda 2021a ), nematodes (Poveda et al 2020 ) and even insects (Poveda 2021b ).…”