Transcriptome changes of fission yeast cells exposed to fumonisin B1 or co-cultured with Fusarium verticillioides

Fusarium verticillioides poses a high food safety risk worldwide due to its mycotoxin production. Successful control of Fusaria may rely on promising biocontrol agents, including yeasts. Although the fission yeast Schizosaccharomyces pombe tolerated Fusarium mycotoxins well, including zearalenone, T2, deoxynivalenol, and fumonisins (FUMs), it did not significantly inhibit the growth of F. verticillioides. Meanwhile fumonisin B1 (FB1) supplementation did not decrease S. pombe cell density in submerged liquid cultures, the colony-forming capability of the yeast was reduced. RNA sequencing showed that S. pombe genes involved in cell adhesion and flocculation were down-regulated after FB1 exposure. In addition, the expression of several hydrolase genes was also altered. In co-cultures with F. verticillioides, genes encoding oxidoreductases and hydrolases and those linked to purine nucleotide metabolisms were down-regulated, while the expression of genes involved in membrane and transport processes was increased. The expression of several F. verticillioides genes also changed after co-cultivation. Oxidoreductase, transmembrane transport, and purine metabolism genes were up-regulated under co-culturing, meanwhile hydrolase genes, together with carbon metabolism and polysaccharide catabolism genes were down-regulated. Co-cultivation also decreased fumonisin production via the down-regulation of genes FUM19, FUM21, and FvATFA encoding the fumonisin transporter, a local Zn(II)2Cys6-type transcriptional regulator and an important global regulator bZIP-type transcription factor, respectively. Although further experiments should clarify the mechanism of the fission yeast-elicited inhibition of fumonisin production, these results may pave the way for the development and implementation of novel, innovative approaches to control mycotoxin production by F. verticillioides in the feed and food chain. Overall design: To investigate the gene expression changes in Schizosaccharomyces pombe and Fusarium verticilloides during co-cultivation using RNA sequencing. Samples: Control S. pombe (14 - S. pombe control) Control F. verticilloides (F3 - F. verticilloides control) Co-cultured S. pombe with F. verticilloides (6 - S. pombe co-cultivated with F. verticilloides) Co-cultured F. verticilloides with S. pombe (Fv3 - F. verticilloides co-cultivated with S. pombe) Each samples have 2 technical replicates. Control Groups: S. pombe and F. verticilloides grown separately. Co-cultivation Groups: S. pombe and F. verticilloides grown together to assess the impact of co-cultivation on gene expression. To investigate the gene expression changes in Schizosaccharomyces pombe in exposure to 0.5 ppm fumonisin B1 Samples: Control S. pombe (K1 - S. pombe control) Control F. verticilloides (M1 - S. pombe treated with 0.5 ppm fumonisin B1) Each samples have 3 technical replicates. Control Group: S. pombe grown in MXGB media. Treated Group: S. pombe grown in MXGB media supplemented with 0.5 ppm fumonisin B1.