Molecular characterization of the Cysteine2-Histidine2 transcription factor Ace1 in Fusarium verticillioides

Abstract

Fusarium verticillioides is a pathogen of corn that causes yield losses and food safety issues due to mycotoxin production. This research project focuses on a cysteine2- histidine2 transcription factor, named FvAce1, which is predicted to play a critical role in regulating fungal colonization of corn kernels and subsequent mycotoxin production. In particular, earlier studies have shown that FvAce1 is critical for utilization of sorbitol as carbon source in F. verticillioides. The objective of this study was to test the hypothesis that F. verticillioides FvAce1 shares conserved function with Trichoderma reesei Ace1. To test this hypothesis, we created a construct harboring T. reesei Ace1 gene, and complemented F. verticillioides FvAce1 null mutant. If the function of the two genes is conserved, we would anticipate restoration of wild-type phenotypes in the complemented F. verticillioides strain. The result showed that the complemented strains were able to grow on sorbitol as the sole carbon source, which suggested T. reesei Ace1 can restore the loss of function caused by FvAce1 mutation. Better understanding of how F. verticillioides FvAce1 regulate diseases on corn and mycotoxin production can lead to improve disease and mycotoxin management.