生物钟是植物从时间上调控免疫系统，平衡生长和抗病以提高其对环境适应性的一种重要手段。另一方面，病原菌也可能会利用植物的生物钟，实现增强其致病性的目的。我们将以病原效应子和与之互作的植物蛋白为切入点，探究病原菌如何影响生物钟这一亟待解决的科学问题。初步研究显示TCP家族转录因子与多个病原效应子互作，其中CHE为生物钟的核心组分。因此，本项目将以拟南芥为研究材料，以CHE为重点研究对象，利用免疫共沉淀与质谱法鉴定与其互作的蛋白；利用转录组测序及染色质免疫共沉淀技术鉴定其调控的下游基因；并进一步明确来源于细菌、真菌和卵菌三种不同类型病原菌的效应子对CHE的亚细胞定位、蛋白互作、下游调控基因和生物钟相关表型的影响。本项目的预期结果是阐明病原效应子通过TCP转录因子调控植物生物钟的细胞分子机制；通过发现不同来源的效应子作用于生物钟的共性特征，为今后设计具有广谱抗病性和较好环境适应性的作物提供新思路。

Circadian clock plays a critical role in the temporal regulation of the plant immune system to balance growth and defense, which is key to the improved fitness of plants. On the other hand, pathogen may hijack plant circadian clock to enhance its pathogenicity. However, little is known about how pathogen affects the plant circadian clock. We aim to focus on pathogen effectors and their interacting host proteins to address this important scientific question. Previous studies have revealed that a large number of effectors from bacteria, oomycete and fungal pathogen interact with only a small set of plant host proteins, which include several TCP family transcription factors (TFs). CHE, also known as TCP21, is among these pathogen target proteins and functions as a plant central clock component. Therefore, CHE is a potential connecting point linking pathogen effectors and plant circadian clock. In this study, we will mainly investigate how pathogen effectors affect plant circadian clock through CHE in the model plant Arabidopsis. First, we will perform immunoprecipitation and mass spectrometry to identify CHE interacting proteins. Meanwhile, RNA-seq and ChIP-seq will be used to find downstream genes regulated by CHE. Based on these transcriptome and proteome data, we will further explore how different pathogen effectors affect CHE subcellular localization, its interactome and its downstream genes. Finally, whether pathogen effectors modulate clock gene expression, circadian output gene expression, plant fitness and pathogen resistance will be assessed. In summary, this study is expected to dissect the molecular mechanisms of how pathogen effectors regulate Arabidopsis circadian clock through TCP TFs. The shared pathogenesis by different types of pathogens uncovered by this project may facilitate the rational design of crops with broad-spectrum pathogen resistance and enhanced fitness in the future.