Fig. 1

Loss of BP1 function upregulates DON production in Fusarium graminearum. A Diagram of the deoxynivalenol (DON) biosynthesis pathway. B Expression levels of TRI genes, as determined by transcriptome deep sequencing (RNA-seq; data were normalized to wild-type PH-1; ΔBP1/PH-1). C Relative transcript levels of TRI genes in wild-type PH-1 and ΔBP1 as determined by reverse transcription quantitative PCR (RT-qPCR). Transcript levels were normalized to ACTIN, with levels in PH-1 set to 1. Different lowercase letters denote significant differences at P = 0.05. D Genome browser view of normalized BP1-GFP chromatin immunoprecipitation sequencing (ChIP-seq) peaks at representative TRI loci. The track scale is 0–300. E Verification of ChIP-seq results by ChIP-qPCR of the indicated TRI genes in ΔBP1::BP1-GFP (the complementation strain, ΔBP1-C) using an anti-GFP antibody. Different lowercase letters denote significant differences at P = 0.05. F Toxisome formation in the wild-type PH-1, ΔBP1, and ΔBP1-C strains inoculated on a wheat (Triticum aestivum) leaf for 2 days. G GFP signal intensity for each strain, with levels in PH-1 set to 1. Different lowercase letters denote significant differences at P = 0.05. H Immunoblot analysis of proteins isolated from the same set of samples used in F, detected with an anti-GFP antibody. GAPDH was used as a loading control. I DON contents in the wild-type PH-1, ΔBP1, and ΔBP1-C complement strains after 7 days of incubation in YEPD medium. Different lowercase letters denote significant differences at P = 0.05 based on one-way ANOVA test