Overexpression of transcription factor AtMYB44 facilitates Botrytis infection in Arabidopsis

Botrytis cinerea is a nonspecific necrotrophic fungal pathogen that attacks many crop plants. It triggers plants to generate large amounts of ROS and induces local cell death to facilitate infection. In this study, we found that transgenic AtMYB44 overexpression in Arabidopsis resulted in stronger ROS burst, greater cell death, and more severe necrosis symptoms than the wild-type and atmyb44 mutant plants following Botrytis infection. Additionally, infected leaves of plants overexpressing AtMYB44 displayed stronger activities of the antioxidative enzymes than other plants. Our findings suggest that the ROS burst is probably associated with AtMYB44-mediated signaling in response to Botrytis attack.

► Reactive oxygen species are important molecules in A. thalinia-B. cinerea interactions.
► AtMYB44 overexpressing Arabidopsis increases susceptibility to Botrytis infection.
► More H2O2 accumulation facilitates infection in AtMYB44 overexpressing Arabidopsis.