FEATURES OF TRI101, THE TRICHOTHECENE 3-O-ACETYLTRANSFERASE GENE, RELATED TO THE SELF-DEFENSE MECHANISM IN FUSARIUM-GRAMINEARUM

A structural gene of Tri101, which encodes trichothecene 3-O-acetyltra nsferase, was isolated as a 3-kb XTroI-XbaI fragment from the trichoth ecene producer Fusarium graminearum strain F15. The gene contained no introns, and the coding region was 0.7-kb downstream of a putative UTP -ammonia ligase gene which obviously is not related to the biosynthesi s of trichothecenes. Tri101 was expressed when T-2 toxin was added, bu t this induction was not dependent on the expression level of Tri6, a transcription activator gene in the trichothecene biosynthetic and reg ulatory gene cluster.