小麦赤霉病严重危害我国和世界小麦生产，发病麦粒中的真菌毒素DON严重危害人畜健康。前期研究发现，cAMP-PKA信号途径可参与调控禾谷镰刀菌致病性并影响DON产生，但该信号途径调控DON产生的分子机制尚不清楚，对其下游转录因子及作用机制也缺乏了解。为此，项目拟深入分析cAMP-PKA信号途径对DON毒素合成的调控机制；通过对该信号通路上PKA两个催化亚基基因双敲除突变体不同表型角变子重测序及结果分析、验证，确定cAMP-PKA信号通路下游相关转录因子；对这些转录因子进行功能分析，并明确它们之间的相互作用关系以及与MAPK信号通路之间的作用关系，确定受两个信号通路共同调控的下游转录因子；同时明确这些下游转录因子在DON毒素产生中的作用。研究结果将会进一步了解cAMP-PKA信号通路在赤霉菌致病和产毒方面的作用机制，为小麦赤霉病的防控和新型杀菌剂的研发提供有效的理论依据。

Wheat scab or head blight caused by Fusarium graminearum is one of the most important diseases of wheat and barley worldwide. It not only causes significant yield losses but also results in the contamination of infected kernels with mycotoxins, such as deoxynivalenol (DON) that are harmful to human and animals. Although the functions of cAMP-PKA pathway in F. graminearum have been studied, genetic mechanisms responsible for the regulation of DON synthesis by this pathway are not clear. To date, there are no studies on downstream targets and transcription factors (TFs) of the cAMP-PKA pathway in this important pathogen. In this study, we will further analyze the regulatory mechanisms of cAMP-PKA pathway on DON production and toxisome formation. Genes responsible for suppressing growth, DON production and infection defects of the cpk1 cpk2 double mutant will be identified and characterized for suppressor mutations. We also propose identify and characterize downstream TFs of the cAMP-PKA pathway and determine their functional relationships. Some of them may be co-regulated by the cAMP-PKA singaling and MAP kinase pathways and are important for the cross-talking between these two important pathways. In additional, we will analyze the regulatory mechanisms of downstream TFs on DON production. Results from the proposed study will significantly improve our understanding for the roles of cAMP-PKA pathway in plant infection and DON production in F. graminearum. In the long run, this study will provide useful information for developing novel fungicide targets and scab disease control strategies.