Fig. 4: Regulation of artA-gene cluster gene expression by C. elegans.

a Expression levels of four genes of the artA cluster (artA, artB, artC, and artD) were repressed after addition of C. elegans. D. flagrans spores were germinated on cellophane paper on LNA medium and grown overnight at 28 °C. Then seven-day-old cultured nematodes (about 50,000) were added and mycelia harvested at the times indicated and processed for quantitative real-time RT PCR analysis (mean ± SD, n = 3 biological with 3 technical replicates; asterisks represent significance levels as determined with the unpaired t test compared to WT; *p < 0.05, artA 0 h vs 6 h, p-value = 0.025; artB 0 h vs 6 h, p-value = 0.027; artC 0 h vs 6 h, p-value = 0.030; artD 0 h vs 6 h, p-value = 0.020). b Scheme of the ascaroside blend isolation (left, pictures were used from the ChemDraw software package). Microscopic visualization of the expression of artA (strain SXY17) after treatment with worms or the ascarosides blend in hyphal tips (right). Scale bar, 20 µm. Source data are provided as a Source Data file.