Plant Innate Immunity against Necrotrophic Pathogens

坏死性病原体在感染的早期阶段杀死植物细胞，从死亡的植物细胞中提取营养物质，使病原体生长和增殖，从而引起疾病。为了诱导植物细胞死亡，坏死性病原体向植物组织释放毒素、活性氧和水解酶。植物对坏死性病原体的免疫反应涉及防御机制，如抗菌化合物的产生和病原体诱导的细胞死亡的抑制。植物细胞中不同的防御反应是如何协调调节的，人们知之甚少。拟南芥WRKY33转录因子对植物抗坏死性病原体具有重要意义。缺乏功能性WRKY33基因的植物对坏死性真菌病原菌灰霉病菌（Botrytis cinerea）和油菜互花菌（Alternaria brassicola）的易感性大大增加。WRKY33作为一种转录因子，调控植物核中参与防御反应的基因。此外，WRKY33还与叶绿体转录和自噬相关的蛋白质相互作用，自噬是一种蛋白质降解途径，对营养循环和细胞存活至关重要。本研究将分析WRKY33、叶绿体转录和自噬途径在植物防御坏死性病原体中的调控、功能和协调。研究人员将继续分析wrky33相互作用的叶绿体转录因子在植物抗坏死性病原体中的功能。研究人员将研究自噬的激活、作用和作用机制，以促进植物细胞在对坏死性病原体的反应中存活。此外，研究人员将分析对坏死性病原体的综合免疫反应所需的三种途径的功能相互作用。这些研究的进展将有助于建立一个全面的植物免疫系统来对抗坏死性病原体。这些知识对于开发控制坏死性病原体的新策略是必要的，坏死性病原体在作物和森林植物中引起许多毁灭性疾病。该项目将为研究生和本科生提供培训，包括在科学领域代表性不足的学生。

Necrotrophic pathogens cause diseases by killing plant cells during early stages of infection to extract nutrients from dead plant cells for pathogen growth and proliferation. To induce plant cell death, necrotrophic pathogens release toxins, reactive oxygen species and hydrolytic enzymes into plant tissues. Plant immune responses against necrotrophic pathogens involve defense mechanisms such as production of antimicrobial compounds and suppression of pathogen-induced cell death. How distinct defense responses are coordinately regulated in plant cells is poorly understood. Arabidopsis WRKY33 transcription factor is important for plant resistance to necrotrophic pathogens. Plants lacking a functional WRKY33 gene display greatly increased susceptibility to necrotrophic fungal pathogens Botrytis cinerea and Alternaria brassicicola. As a transcription factor, WRKY33 regulates plant nuclear genes involved in defense responses. In addition, WRKY33 physically interacts with proteins involved in chloroplast transcription and autophagy, a protein degradation pathway critical for nutrient recycling and cell survival. This research will analyze the regulation, functions and coordination of the WRKY33, chloroplast transcription and autophagy pathways in plant defense against necrotrophic pathogens. The investigators will continue functional analysis of WRKY33-interacting chloroplast transcription factors in plant resistance to necrotrophic pathogens. The investigators will examine activation, roles and action mechanisms of autophagy in promoting plant cell survival during responses to necrotrophic pathogens. In addition, the investigators will analyze functional interactions of the three pathways required for an integrated immune response to necrotrophic pathogens. Progress in these studies will help establish a comprehensive plant immune system against necrotrophic pathogens. This knowledge is necessary for development of new and novel strategies for controlling necrotrophic pathogens, which cause many devastating diseases in crop and forest plants. The project will provide training for both graduate and undergraduate students, including students underrepresented in sciences.