稻曲病严重影响我国水稻安全生产和稻米品质。有性生殖是稻曲病菌重要的繁殖方式，申请者克隆了稻曲病菌交配型基因座；本项目拟在前期研究基础上，阐明交配型基因座MAT1-2位点调控稻曲病菌有性生殖过程；构建MAT1-2位点基因MAT1-2-1和MAT1-2-8的敲除突变体及回复突变体，分析其在有性生殖过程中生物学特性；采用qRT-PCR和荧光蛋白标记技术明确MAT1-2-1 和MAT1-2-8的表达规律及表达产物亚细胞定位；通过转录组测序比较基因敲除突变体与野生型菌株差异，分析参与MAT1-2位点调控的基因，同时采用酵母双杂交、基因功能互补等方法筛选和验证MAT1-2-1、MAT1-2-8互作因子，解析相关因子参与MAT1-2位点调控稻曲病菌有性生殖的信号网络。预期结果对在分子水平认识稻曲病菌有性生殖和侵染循环过程、制定稻曲病防控策略有重要价值。

Rice false smut, caused by Ustilaginoidea virens, is an important disease of rice in the worldwide, also heavily reduced the quantity and quality of rice. The sexual reproduction process of U. virens played an important role in the infection cycle. However, the molecular mechanism of sexual reproduction is still uncovered. We have cloned the mating-type idiomorphs of U. virens (MAT1-1 and MAT1-2), and proved this pathogen as a heterothallic ascomycetous fungus. To further elucidate the mechanisms of mating-type idiomorph MAT1-2 involving in sexual reproduction, we will carry out studies in this project as follows: 1) Construct single-gene knockout, double-gene knockout and complementary mutants of MAT1-2-1 and MAT1-2-8 mating-type genes in MAT1-2 idiomorph, respectively. Study the biological characteristics, sclerotia formation and sexual reproduction processes after inoculating these mutants in combination with MAT1-1 mating-type strains on rice; 2) Explain the temporal and spatial expression patterns of the mating-type genes in MAT1-2 idiomorph and subcellular localization of their protein, by using the real-time PCR and GFP fusion expression technologies respectively; 3) Analysis the transcriptomes of gene-deletion mutants and wild-type strain mentioned in “1)” to carry out the differentially expressed genes associated with the MAT1-2 idiomorph; The MAT1-2-1 and MAT1-2-8 will be employed as bait to screen 2-4 interaction factors by using yeast two-hybrid technology; 4) Study will be further focused on the interaction factors mentioned in“3)”, to elucidate their function in the sexual reproduction of U. virens. Generally, this research project will be therefore of great significance to reveal the sexual life cycle and molecular mechanism of sexual reproduction process of U. virens, and also will be valuable for understanding the pathogenic mechanisms of U. virens and disease epidemic rules and development of the disease control strategy.