The Fusarium verticillioides minichromosome negatively regulates the biosynthesis of carcinogenic fumonisins during maize infection

fumonisin levels in infected maize kernels, yet causes comparable stalk rot and leaf blight as FvSZ22. Notably, ΔChr12/Chr12-harboring the fumonisin biosynthetic gene cluster (FBGC) from FvSZ22 and Chr12 from LNF15-11-produces drastically higher levels of both fumonisins, linked to the FBGC upregulation. This study underscores the indispensability of minichromosomes in regulating mycotoxin biosynthesis and fungal adaptation to environmental stress.