稻曲病是我国水稻三大病害之一，其病原菌分泌的效应蛋白在其侵染水稻的过程中发挥重要作用。稻曲病菌编码的大部分效应蛋白都是不保守的，本研究前期分析193个候选效应蛋白的保守性发现SCRE3在多种子囊菌中高度保守。表达模式分析结果显示SCRE3基因在稻曲病菌侵染水稻时被显著诱导表达，SCRE3强烈抑制植物的免疫反应，并且Δscre3突变体菌株对水稻的致病性显著降低。此外，SCRE3与水稻CIN类TCP转录因子ETF1在酵母中互作。以上研究结果表明SCRE3及其同源蛋白是一类功能未被揭示的关键效应蛋白，它们分布广泛、结构保守，在病原菌致病过程中发挥重要作用，但致病机制未知。基于此，本项目将通过基因敲除、病原菌接种和转录组测序等方法分析SCRE3作用的水稻免疫信号通路，解析其与ETF1互作的生物学意义，揭示其抑制水稻免疫反应的分子机制。研究结果有助于深入理解稻曲病菌独特的侵染机制和发掘水稻抗病基因。

Rice false smut is one of the three major rice diseases in China, and the secreted effectors play an important role during Ustilaginoidea virens infection. Most effectors in U. virens generally share a relatively low amino acid sequence similarity among closely-related fungal species. Previous studies have showed that the effector SCRE3 from U. virens was conserved in multiple ascomycete species by analyzing the conservation of 193 candidate effectors. Expression pattern analysis showed that the transcription of SCRE3 was induced during U. virens infection, and SCRE3 strongly inhibited plant immune response, as well as the pathogenicity of Δscre3 knockout mutants was significantly reduced. In addition, Yeast two-hybrid assay showed SCRE3 interacted with ETF1, a rice TCP CIN-type transcription factor. The results suggest that SCRE3 and its homologous proteins may be a critical unidentified effector family, as well as they are widely distributed and have conserved domains, also play an important role in the infection process of the pathogen, but the pathogenic mechanism is unclear. In view of this, this project intends to further analyze the immune signaling pathways in rice targeted by SCRE3, along with the biological function of the interaction between SCRE3 with ETF1, and illuminate the molecular mechanism of SCRE3-mediated suppression of rice immune response by gene knockout, pathogen inoculation, RNA-Seq, etc. The results will help to further understand the unique infection mechanism of U. virens and excavate rice disease resistance genes.