乳杆菌属是形成发酵蔬菜特征风味的核心微生物。发酵蔬菜中Kazachstania属酵母菌可通过跨界信号分子胞外囊泡（EVs）miRNA对乳杆菌菌群结构产生调节作用，然而对于该过程的调节模式及分子机制尚不清楚。项目以发酵蔬菜的典型代表四川泡萝卜为研究对象，通过EVs miRNA测序与种水平高通量测序，明确对乳杆菌菌群结构起调节作用的关键EVs miRNA；通过添加外源关键EVs miRNA建立高保真模拟体系，阐明EVs miRNA通过对靶标与非靶标乳杆菌的选择性调控进而调节菌群结构的作用模式；采用富集分析和代谢组学方法，阐释关键EVs miRNA对靶标乳杆菌代谢通路中关键酶系转录表达水平及其代谢物的调控机制，并解析靶标乳杆菌代谢转变对非靶标乳杆菌生长代谢的影响，从跨物种信号传导角度揭示发酵蔬菜中乳杆菌菌群结构的形成规律及分子调节机制。本项目的开展可为我国传统发酵工艺的可控化改进提供理论依据。

Lactobacillus is the critical core microbiota for the formation of characteristic flavor of fermented vegetable. Kazachstania could regulate the Lactobacillus communities via the cross-kingdom signaling molecule-extracellular vesicles miRNA (EVs miRNA), but its exact regulatory mode and mechanisms are still unclear. In this project, Sichuan raddish paocai, a classic fermented vegetable in China, will be selected as the research object to clarify the regulatory mode and molecular mechanism underlying the cross-kingdom interactions between Kazachstania and lactobacillus community. Firstly, the key EVs miRNA, which plays a major role in regulating the Lactobacillus community structure, will be identified by the EVs miRNA sequencing combined with high-throughput sequencing at Lactobacillus species level. Then, to elucidate the regulatory mode which shapes the Lactobacillus community structure, the targeted and non-targeted Lactobacillus species will be systematically differentiated through adding the exogenous miRNA mimics to the high-fidelity simulation system of fermented vegetable. Finally, the enrichment analysis and metabolomics will be adopted to illuminate the mechanism underlying the regulatory effect of EVs miRNA on the transcription and expression levels of key enzymes and metabolites in relevant metabolic pathway of targeted Lactobacillus species, thus further addressing the effect of the changes in metabolism of targeted Lactobacillus species on the growth of non-targeted Lactobacillus species. Overall, in this study, the regulatory mode and the molecular mechanism underlying the formation of Lactobacillus community structure shaped by EVs miRNA from Kazachstania could be clarified from the perspective of cross-kingdom signal transduction. This study will contribute to the controllable improvement of fermentation technology for traditional fermented food in China.