表观遗传调控挖掘无花果拟盘多毛孢次级代谢产物的结构多样性

Structure diversity of fungal secondary metabolite plays an important role in development of the modern drug. Activation of cryptic gene cluster leading to discovery of novel compound provides an efficient way to improve the structural diversity. Epigenetic regulation strategy shows an unique advantage in activating cryptic gene clusters. Here, we will conduct the following research based on epigenetic regulation strategy using Pestalotiopsis fici as materials: 1) to identify the epigenetic regulation factors in P. fici by blast search sequence homology of proteins characterized in model fungi such as CclA. and obtain the mutants by gene knock-out methodologies. 2) to isolate and elucidate the compounds from mutants in which the cryptic gene clusters are activated, meanwhile to evaluate the biological activity. 3) to investigate the effect of different epigenetic regulators on the content of the regulated secondary metabolites with quantitative analysis method and the underlying mechanisms. The approaches used in this study will greatly accelerate the discovery of new natural compounds and be very helpful to activation of silent gene cluster. This study will be very significant in structural diversity development of fungal secondary metabolite from complicated environments.

真菌次级代谢产物结构多样性是现代天然药物开发的基础，从真菌基因组中激活“沉默”的基因簇到新化合物发现将是提高结构多样性的有效途径之一。表观遗传调控技术在激活“沉默”基因簇发现化合物等方面展现其独特优势。本项目拟以全基因组测序完成的无花果拟盘多毛孢为材料，基于表观遗传调控策略，开展如下研究：1）以模式真菌中调控次级代谢的重要表观遗传调控因子，如CclA等为靶标进行蛋白序列比对，鉴定该菌中的同源基因，利用遗传敲除获得突变株；2）对突变株中“沉默”基因激活后表达的化合物进行分离纯化、结构鉴定及生物活性评价等；3）通过定量分析考察不同表观调控因子对所调控化合物含量的影响，对其机制进行初步探讨。该研究将会大大加速新天然产物发现的步伐，并对复杂环境来源真菌“沉默”基因簇的激活及次级代谢结构多样性开发具有重要参考价值。

真菌次级代谢产物结构多样性是现代天然药物开发的基础，从真菌基因组中激活“沉默”的基因簇到新化合物发现将是提高结构多样性的有效途径之一。表观遗传调控技术在激活“沉默”基因簇发现化合物等方面展现其独特优势。本项目以全基因组测序完成的无花果拟盘多毛孢为材料，基于表观遗传调控和遗传敲除策略，获得表观遗传调控因子CclA和HdaA基因以及COP9核小体亚基csnE基因缺失突变株；并对其相应的突变株中“沉默”基因激活后表达的化合物进行分离纯化、结构鉴定；获得了15个新的聚酮类化合物和5个新结构化合物。此外，PfCclA、PfHdaA和PfcsnE对无花果拟盘多毛孢发育和次级代谢具有调控作用，这也为研究CSN复合体对其他真菌生长发育及次级代谢产物的研究提供依据，进而为揭示次级代谢产物的生理生态功能奠定基础。该研究将会大大加速新天然产物发现的步伐，并对复杂环境来源真菌“沉默”基因簇的激活及次级代谢结构多样性开发具有重要参考价值。