Abstract
Trichothecenes are a family of closely related phytotoxins produced by several phytopathogenic fungi. Trichothecenes has primarily a problem with elicitors in plants, and acts as inhibitors of protein synthesis on eukaryotic ribosome. We revealed that Arabidopsis plants treated with T-2 toxin, one of trichothecenes, indicated dwarfism, curly leaves and short petioles. We found that AtNF-X1 gene, which is an Arabidopsis homolog of the human putative transcriptional repressor NF-X1 is up-regulated in T-2 toxin treated plants. The accumulation of AtNF-X1 mRNA was increased by T-2 toxin treatment. An atnf-x1 mutant was highly sensitive to T-2 toxin compared to the wild type. These results show that AtNF-X1 acts as T-2 toxin-responsive transcriptional factor. Microarray analysis showed that T-2 toxin increased in mRNA levels of WRKY in atnf-x1 mutant. In these results, we suggest that the AtNF-X1 protein acts as a negative regulator for WRKY.
