Arabidopsis thioredoxin gene (AtTrx5) enhances plant resistance to Sclerotinia.

Sclerotinia is a significant disease that harms the production of cruciferous crops. S. sclerotiorum can induce host to produce excessive reactive oxygen species (ROS), resulting in host cell death, and Trx plays an important role in host antioxidant process. Screening and identifying the relationship between Trx and Sclerotinia resistance will provide genetic resources for plant resistance breeding. In this study, a key gene AtTrx5 was selected from A. thaliana through bioinformatics and transcriptome data analysis. AtTrx5 has the closest relationship with Brassica napus BnaA08g04320D with 85% amino acid homology. Trx5 showed up-regulated expression in the homologous gene in rape. The lesion area of the AtTrx5 overexpression lines was reduced by 30%-39% compared with the WT, while the lesion area of T-DNA mutant was increased by about 39.2% at 24 hpi with S. sclerotiorum. The expression level of AtTrx5 in the overexpression lines was higher than wide type, while AtTrx5 was lower in the T-DNA mutant during the infection. DAB staining, H₂O₂ content, • O^2- content indicated that the accumulation of ROS in T-DNA mutants was significantly higher than that of wide type; while the accumulation of ROS was significantly less in overexpression lines. [ABSTRACT FROM AUTHOR]