内生真菌是新型抗肿瘤物质的重要来源。我们先前从药用植物青蒿中分离出一株内生真菌，即小叶交替孢霉，其粗提物能显著抑制A549肿瘤细胞。我们获得了一个转基因体，命名为AaLaeAOE26，由于全球调控因子AaLaeA的过表达，该转基因体完全丧失了其抗肿瘤活性。基因组再测序分析揭示，插入点位于非编码区域，没有破坏其他基因。代谢组学分析表明，与野生株相比，AaLaeAOE26中二次代谢抗肿瘤物质的水平显著降低，尤其是根据代谢组学分析显示黄酮类物质下调更为明显。进一步比较转录组学分析揭示，编码FAD结合域蛋白(Fla1)的基因明显下调。另一方面，AaFla1的过表达显著增强了对A549的抗肿瘤活性，抑制率较野生株提高了七倍。同时，我们还发现抗肿瘤代谢物质如橡皮素、铁凤元、红景天素、lianinene、人参皂苷Rg2和蟾毒苷的积累显著增加。我们的数据表明，全球调控因子AaLaeA通过控制AaFla1的转录负向影响内生 small> A. alstroemeria产生抗肿瘤化合物。© 2023 Wiley-VCH GmbH.

Endophytic fungi are an important source of novel antitumor substances. Previously, we isolated an endophytic fungus, Alternaria alstroemeria, from the medicinal plant Artemisia artemisia, whose crude extracts strongly inhibited A549 tumor cells. We obtained a transformant, namely AaLaeAOE26 , which completely loses its antitumor activity due to overexpression of the global regulator AaLaeA. Re-sequencing analysis of the genome revealed that the insertion site was in the noncoding region and did not destroy any other genes. Metabolomics analysis revealed that the level of secondary antitumor metabolic substances was significantly lower in AaLaeAOE26 compared with the wild strain, in particular flavonoids were more downregulated according to the metabolomics analysis. A further comparative transcriptome analysis revealed that a gene encoding FAD-binding domain protein (Fla1) was significantly downregulated. On the other hand, overexpression of AaFla1 led to significant enhancement of antitumor activity against A549 with a sevenfold higher inhibition ratio than the wild strain. At the same time, we also found a significant increase in the accumulation of antitumor metabolites including quercetin, gitogenin, rhodioloside, liensinine, ginsenoside Rg2 and cinobufagin. Our data suggest that the global regulator AaLaeA negatively affects the production of antitumor compounds via controlling the transcription of AaFla1 in endophytic A. alstroemeria.© 2023 Wiley-VCH GmbH.