Arabidopsis thaliana detoxification gene AtDTX1 is involved in trichothecene 3-acetyl-deoxynivalenol efflux

Authors: Hao, Guixia; Edwards, Jackson; RHOADES, NICHOLAS - Orise Fellow; McCormick, Susan

Submitted to: Frontiers in Plant Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/21/2025
Publication Date: 5/18/2025
Citation: Hao, G., Edwards, J., Rhoades, N., McCormick, S.P. 2025. Arabidopsis thaliana detoxification gene AtDTX1 is involved in trichothecene 3-acetyl-deoxynivalenol efflux. Frontiers in Plant Science. 16:1574367. https://doi.org/10.3389/fpls.2025.1574367.
DOI: https://doi.org/10.3389/fpls.2025.1574367

Interpretive Summary: The fungal pathogen Fusarium graminearum causes Fusarium head blight (FHB) on wheat and produces vomitoxin (deoxynivalenol or DON) and its acetylated forms 3-acetyl-DON and 15- acetyl-DON. These toxins are commonly found in diseased grain and can cause serious health problems in humans and animals. It is critical to develop novel methods to control FHB and mycotoxin contamination due to a lack of resistant plant varieties and emerging fungicide resistant strains. Plant transporters are proteins that can detoxify and dispose toxins from plant cells. To reduce mycotoxin and FHB, we identified an Arabidopsis transporter (AtDTX1) that pumped toxin 3-ADON out of Arabidopsis cells to protect plants. Further research on co-expressing AtDTX1 and Fusarium self-protection gene TRI101 will provide a strategy to reduce FHB and toxin contamination.

Technical Abstract: The fungal pathogen Fusarium graminearum causes Fusarium head blight (FHB) on wheat and produces trichothecene mycotoxins that contaminate grains. Deoxynivalenol (DON) and its acetylated derivatives, including 3-acetyl-DON (3-ADON) and 15-acetyl-DON (15-ADON), are the most common trichothecenes found in contaminated grains, which causes food and feed safety issues. Approaches that detoxify DON can reduce FHB and mycotoxin contamination. Our previous study showed that transgenic Arabidopsis thaliana expressing a F. graminearum 3-O-acetytralferase self-protection enzyme (FgTri101), converted DON to 3-ADON and excreted 3-ADON out of plant cells to protect plant growth and development. The goal of the study was to identify the transporter involved in 3-ADON excretion and utilize it to reduce toxicity and FHB. To identify trichothecene transporter candidates, transcriptomic studies were conducted on FgTri101 transgenic A. thaliana seedlings treated with DON (50 mg/L, 24 h) versus untreated controls. Transcriptomic analyses revealed that three transporter genes, including two A. thaliana detoxification genes (AtDTX1 and AtDTX3) and one ABC transporter (ABCB4), were upregulated by DON treatment. Atdtx1 mutant transported 3-ADON less efficiently than Atdtx3 and Atabcb4 mutants. Therefore, the A. thaliana Col-0 mutant Atdtx1 line was transformed and expressed FgTRI101. The Atdtx1 mutant lines expressing FgTRI101 showed resistance to DON but had significantly shorter roots than the FgTRI101 Col-0 transgenic line. Furthermore, significantly less 3-ADON was detected in the media used to grow the transgenic Atdtx1 mutant seedlings expressing FgTRI101 than the Col-0 seedlings expressing FgTRI101. These data indicate that AtDTX1 is involved in efflux of 3-ADON and that at least another transporter or other mechanism is associated with 3-ADON transport.