ABSTRACT: Fusarium head blight (FHB) is a devastating fungal disease of cereal crops causing substantial reductions in grain quality and yield, impacting Canada’s economy. Fusarium graminearum, the causative agent of FHB in wheat, also produces harmful mycotoxins, including deoxynivalenol (DON), 3-acetyl DON (3ADON), 15-acetyl DON (15ADON), and nivalenol (NIV), which impact livestock and human health upon consumption of contaminated grains in feed and processed foods, respectively. Critically, over the past 15 years, surveillance programs have defined the synthesis of a novel trichothecene, 3ANX, and the deacetylated variant, NX, with increased virulence compared to DON. In this study, we assessed the impact of 3ANX from dual proteome perspectives of wheat and fungi to identify proteins and pathways activated in response to the emerging chemotype. We defined a core wheat proteome detected across all isolates (15ADON- and 15ADON+3ANX-producing, and untreated controls), and explored changes in protein abundance associated with defense response, seed storage and grain development, and reduced photosynthesis upon infection. Conversely, we identified 32 wheat proteins produced only in the presence of 15ADON+3ANX isolates, providing further insight into chemotype-specific responses of wheat. Assessment from the fungal perspective reported 119 proteins exclusive to the 15ADON+3ANX isolates, including those associated with virulence and mycotoxin production. Lastly, investigation of isolate-specific proteome changes showed a significant reduction in mycotoxin protective mechanisms in wheat upon exposure to two 15ADON+3ANX isolates, as well as a novel connection between elevated ergosterol biosynthesis and 3ANX production in F. graminearum. Together, we our study characterizes distinct protein production profiles in wheat and F. graminearum in response to 3ANX treatment and provides evidence that these molecular changes influence fungal virulence and host defense responses
Seyedehsanaz Ramezanpour 