MicroRNAs (miRNAs) 在动植物中参与基因表达调控，并已有深入研究，但在真菌中对miRNAs的认识却较少。丝状真菌黄曲霉因产生强致癌物黄曲霉毒素（Aflatoxin, AF）而引起广泛关注。我们前期通过黄曲霉野生型产毒株、5-氮杂胞苷及没食子酸处理后的非产毒株小RNA测序数据，证实黄曲霉中存在类miRNAs分子。本项目将对黄曲霉中的类miRNAs进行功能研究，重点关注类miRNAs在AF生物合成中的作用。主要研究内容有：（1）检测不同发育阶段类miRNAs的表达情况，明确其表达模式；（2）对类miRNAs进行敲除及过表达，对突变株进行表型及次级代谢物等指标的检测，明确其在黄曲霉中的作用；（3）对类miRNAs可能调控的靶基因进行调控关系验证，并进行上下游通路分析，阐明类miRNAs参与AF合成调控的具体机制。本研究将为进一步解析AF等次级代谢物合成调控机制提供新的理论依据。

MicroRNAs (miRNAs) regulate gene expression in animals and plants and have been deeply studied, but the role of miRNAs in fungi was less understood. Filamentous fungi Aspergillus flavus has caused wide concerns due to the production of carcinogenetic aflatoxin (AF). We have demonstrated the existence of miRNA-like RNAs (milRNAs) in A. flavus through the small RNA sequencing data of wild type A. flavus (aflatoxin-producing), and 5-azacytidine (5-AC) and gallic acid (GA) treated non-aflatoxin producing A. flavus. In this research, we will undertake the functional study of milRNAs in A. flavus, and focus on the role of milRNAs in AF biosynthesis. The main contents are: (1) we will detect the milRNAs expression in different development stage, and demonstrated the expression pattern of milRNAs; (2) we will conduct the deletion and over-expression of milRNAs to confirm the effects of milRNAs in A. flavus by detection of phenotypes and secondary metabolites production in milRNAs mutant strains; (3) we will verify the regulatory role of milRNAs on target genes and analyze the upstream and downstream pathways to illustrate the specific regulatory mechanism of milRNAs on AF synthesis. Our research will provide new perspectives for further illustration of AF and other secondary metabolites synthesis mechanism.