Novel Zn(II)Cys Transcription Factor BcFtg1 Enhances the Virulence of the Gray Mold Fungus by Promoting Organic Acid Secretion and Carbon Source Utilization.

The Zn(II)Cys zinc cluster protein family comprises a subclass of zinc-finger proteins that serve as transcriptional regulators involved in a diverse array of fugal biological processes. However, the roles and mechanisms of the Zn(II)Cys transcription factors in mediating , a necrotrophic fungus that causes gray mold in over 1000 plant species, development and virulence remain obscure. Here, we demonstrate that a novel pathogenicity-associated factor (ungal ranscription factor containing the AL4 domain), identified from a virulence-attenuated mutant M20162 from a T-DNA insertion mutant library, plays an important role in oxalic acid (OA) secretion, carbon source absorption and cell wall integrity. Loss of compromises the ability of the pathogen to secrete OA, absorb carbon sources, maintain cell wall integrity, and promote virulence. Our findings provide novel insights into fungal factors mediating the pathogenesis of the gray mold fungus via regulation of OA secretion, carbon source utilization and cell wall integrity.