里氏木霉Set2通过调控转录因子Ypr1的表达进而控制sorbicillinoids的生物合成

Trichoderma reesei Set2 modulates sorbicillinoid biosynthesis via regulating the expression of transcription factor Ypr1

摘要:

【目的】Sorbicillinoids是里氏木霉合成的一类重要的天然活性物质，具有抗肿瘤、抗氧化及抗病毒等多种生物活性。本研究主要是为了阐明TrSet2在里氏木霉sorbicillinoids合成调控过程中的生物学功能及其作用机制。【方法】基于生物信息分析技术鉴定里氏木霉TrSet2编码基因。采用基因敲除和过表达手段，分别构建Trset2基因敲除和过表达菌株并评估其sorbicillinoids合成能力。同时在Trset2基因敲除菌株中，过表达转录激活因子Ypr1，明确TrSet2和Ypr1之间的调控关系。【结果】Trset2基因敲除菌株完全丧失了合成sorbicillinoids的能力。相反，过表达Trset2导致sorbicillinoids合成的水平显著增加。进一步研究发现，在Trset2基因敲除菌株中过表达转录激活因子Ypr1逆转了其不能合成sorbicillinoids的表型。【结论】本研究明确了TrSet2在里氏木霉合成sorbicillinoids过程中的正向调控作用，其作用机制是通过控制转录因子Ypr1的表达水平实现的。这为基于调控机理控制里氏木霉发酵过程中sorbicillinoids的产生或构建高水平合成sorbicillinoids的细胞工厂提供了理论依据和指导。

Abstract:

[Objective] Sorbicillinoids are important natural active compounds synthesized by Trichoderma reesei and exhibit various biological activities, such as antineoplastic, antioxidative, and antiviral properties. In this study, we aimed to clarify the biological functions and regulatory mechanisms of TrSet2 during sorbicillinoid biosynthesis in T. reesei. [Methods] Weidentified the gene encoding TrSet2 in T. reesei using bioinformatic analysis, and investigated its functions in sorbicillinoid biosynthesis by knockouting and overexpressing Trset2 gene. In addition, the transcription activator Ypr1 was overexpressed in Trset2 knockout strain to elucidate the regulatory mechanism between TrSet2 and Ypr1. [Results] Knockout of Trset2 led to the strain's inability to synthesize sorbicillinoids. Conversely, overexpression of Trset2 resulted in a significant increase in sorbicillinoid secretion. Further studies showed that overexpression of Ypr1 in Trset2 knockout strain restored sorbicillinoid production. [Conclusion] TrSet2 positively regulated the sorbicillinoid biosynthesis via controlling the expression of Ypr1. Our results facilitated the control of sorbicillinoid secretion during the fermentation of T. reesei and the development of cell factories for high-level synthesis of sorbicillinoids based on the regulatory mechanism.