CAREER: Regulatory Mechanisms of Pathogen-Mediated Cellular Stress Signaling in Arabidopsis: Taking Plant Molecular Biology to the Urban Garden

非技术摘要：这个项目将建立一个创新和连贯的平台，显著提高我们对病原体介导的植物内质网(ER)胁迫的理解，培训下一代少数族裔科学家，并让城市社区参与公民科学。该项目的研究范围涉及细胞压力和未折叠蛋白质的积累与植物免疫系统之间的独特联系。在病原体攻击下，植物细胞增加新肽的产生，从而给内质网中的蛋白质折叠机制带来负担，导致细胞应激。通过这个项目，研究人员将了解在拟南芥中有效缓解这种逆境反应的分子机制。从这项研究中获得的见解将通过阐明培育能够在细胞压力增加的情况下发挥作用的作物的机制来影响农业科学，这对更可持续的未来是必要的。亚利桑那州伯明翰是全国人口最多样化和最贫困的城市之一(74%的非裔美国人，25%处于贫困线以下)，研究人员处于独特的地位，可以通过面向代表不足和社会经济贫困的少数群体的外联计划来促进与植物生物学相关的教育。研究人员将实施一个综合服务和发现为基础的学习推广平台“OutPace”(推广植物病理学诊所和教育)，面向本科生和公民科学家：当地社区花园的低收入城市园艺家庭。OutPace将使学生能够获得基于实验室和田间的植物免疫知识，并帮助社区种植者诊断植物疾病。这些努力与当前旨在加强公民参与和可持续生活以及与城市营养不良和饥饿作斗争的区域倡议很好地结合起来。技术摘要：肌醇需求酶1(IRE1)是一种高度保守的真核细胞内质网应激感受器。虽然慢性内质网应激与后生动物免疫紊乱有关，但IRE1a在植物免疫中的作用仍然难以捉摸。最近，这位首席研究者首次建立了已知的拟南芥免疫信号中转录因子bZIP60的IRE1a与其客户mRNA之间的联系。基于这些发现，研究人员将把他们的研究问题扩展到植物免疫中ER信号的其他关键领域，并解决以下目标：1)了解在ER振荡胁迫条件下生物胁迫依赖的IRE1a激活和失活的分子机制；2)阐明IRE1a在细胞适应或病原体介导的细胞死亡中的调节机制；3)破译IRE1a和水杨酸受体NPR1之间的反馈机制；4)全基因组范围内发现和表征新的IRE1a底物。为了实现这些目标，研究人员将使用成熟的和新开发的方法，包括：突变/转基因植物研究，基于植物荧光报告的显微镜，病原体感染和细胞死亡分析，蛋白质-蛋白质相互作用和酶分析，基于酵母报告的新系统，转录图谱，以及生物信息学辅助分析。

NON-TECHNICAL ABSTRACT:This project will establish an innovative and coherent platform to significantly enhance our understanding of pathogen-mediated endoplasmic reticulum (ER) stress in plants, train next-generation minority scientists, and engage an urban community in citizen science. The research scope of the project addresses a unique connection between the cellular stress and accumulation of unfolded proteins, and the plant immune system. Upon pathogen attack, plant cells increase production of new peptides, which consequently puts a burden on the protein folding machinery in the ER and causes cellular stress. Through this project, the investigators will learn about the molecular mechanisms underlying the efficient alleviation of this stress response in Arabidopsis. The insights gained from this research will impact the agricultural sciences by elucidating mechanisms to develop crop plants with the capacity to function under increased cellular stress - a necessity for a more sustainable future.Situated in Birmingham, AL, a city that has one of the most diverse and impoverished populations nationwide (74% African American, 25% below the poverty line), the investigators are in a unique position to foster plant biology-related education through outreach programs for underrepresented and socioeconomically underprivileged minorities. The investigators will implement an integrative service- and discovery-based learning outreach platform "OUTPACE" (OUTreach plant PAthology Clinic & Education) that is directed towards undergraduate students and citizen scientists: low-income urban gardening families of the local Community Gardens. OUTPACE will enable the students to acquire laboratory- and field-based knowledge of plant immunity and assist community growers in diagnosing plant diseases. These efforts are well aligned with current regional initiatives to enhance civic engagement and sustainable living, and combat urban malnutrition and hunger. TECHNICAL ABSTRACT:Inositol-Requiring Enzyme 1 (IRE1) is a highly conserved eukaryotic endoplasmic reticulum (ER) stress sensor. While chronic ER stress is linked with metazoan immune disorders, the role of IRE1a in plant immunity remains elusive. Recently, the principal investigator established the first known connection between the IRE1a and its client mRNA for the bZIP60 transcription factor in Arabidopsis immune signaling. Based on these findings, the investigators will expand their research questions to other key areas of ER signaling in plant immunity and address the following objectives: 1) Understanding the molecular mechanisms of biotic stress-dependent IRE1a activation and deactivation under oscillating ER stress conditions; 2) Elucidating the regulatory mechanisms of IRE1a functions in cellular adaptation or pathogen-mediated cell death; 3) Deciphering the feedback mechanisms between IRE1a and the salicylic acid receptor NPR1; 4) Genome-wide discovery and characterization of novel IRE1a substrates. To achieve these goals, the investigators will employ well-established and newly developed methodologies, including: mutant/transgenic plants studies, in planta fluorescent reporter-based microscopy, pathogen infections and cell death assays, protein-protein interaction and enzymatic assays, a novel yeast reporter-based system, transcriptional profiling, and bioinformatics-aided analyses.