Activation of silent biosynthetic gene clusters in fungi remains a challenge for discovery of new useful natural products. In this work, we identify a group of silent secondary metabolite gene clusters in Aspergillus nidulans that are induced by rice (Oryza sativa). Using reverse phase HPLC purification on extracts of rice, we identified the plant hormone gibberellic acid as one compound present in rice extracts that induced these silent genes. Additionally, select secondary metabolite (SM) genes activated by rice were tested for responses to several plant hormones which produced distinctly different transcriptomic profiles in A. nidulans. These observations support the idea that phytohormones play an important role in regulating fungal SM biosynthesis while additionally serving as a source of natural product chemical libraries to screen for useful compounds.

真菌中沉默生物合成基因簇的激活仍然是发现新的有用天然产物的挑战。在这项工作中，我们确定了由水稻（水稻（Oryza sativa））诱导的构巢曲霉中一组沉默的次生代谢产物基因簇。通过对稻米提取物进行反相HPLC纯化，我们确定了植物激素赤霉素是稻米提取物中存在的一种诱导这些沉默基因的化合物。此外，测试了水稻激活的次生代谢产物（SM）基因对几种植物激素的反应，这些激素在构巢曲霉中产生截然不同的转录组谱。这些观察结果支持以下观点：植物激素在调节真菌SM生物合成中起着重要作用，同时还充当天然产物化学文库的来源，以筛选有用的化合物。