CAREER: Understanding Plastoglobule Lipid Droplet Function Through the ABC1 Atypical Protein Kinases

该项目旨在揭示植物细胞中最丰富的质体脂滴酶的成员如何促进胁迫耐受性和发育转变。该项目的成果将阐明我们对所有植物共同的抗逆性机制的这一知之甚少的组成部分的理解，对农业生产力和粮食安全具有潜在的深远影响。将提供多种教育项目，包括为本科生提供的植物科学培训项目，为公众宣传活动提供的材料，如每年的植物日魅力，以及为研究生提供的蛋白质组学教学模块。这一系列项目将产生长期影响，为本科生提供新的教育机会，提高研究生的课程内容，促进公众对植物对社会贡献的认识，同时促进PI学员的职业发展。植物叶绿体的质体红脂滴被认为是对环境胁迫的适应性反应的主要协调者。然而，对微球功能的理解仍然局限于假设模型，缺乏实验验证的分子功能。该项目的目的是阐明所有六种定位于微球的ABC1蛋白激酶（ABC1Ks）在微球功能中的核心作用。这些ABC1Ks是微球中最丰富的酶，被认为是通过微球蛋白组的磷酸化调节微球功能的主要调节剂。该项目将描述每个ABC1K的蛋白激酶活性，定义塑料微球蛋白的磷酸化调控网络，剖析ABC1Ks独特的N-和C-末端侧翼的功能相关性，并揭示ABC1Ks的生物学功能。这些目标将通过一系列异种表达ABC1Ks的体外激酶分析和敲除和过表达突变系的表型研究来实现，包括大规模的磷蛋白组学和脂质组学研究。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This project seeks to uncover how members of the most abundant enzymes of plastoglobule lipid droplets of plant cells operate to promote stress tolerance and developmental transitions. Outcomes from this project will illuminate our understanding of this poorly understood component of the stress tolerance machinery common to all plants, with potentially far-reaching impacts for agricultural productivity and food security. Multiple educational programs will be provided, including an REU-style training program in the plant sciences for undergraduate students, materials for public outreach events such as the annual Fascination of Plants Day, and a proteomics instructional module for graduate students. This suite of programs will result in long-term impacts that develop novel educational opportunities for undergraduates, enhance course content for graduate students, and promote an appreciation among the general public of plants’ contribution to society, while fostering the career development of the PI’s trainees.Plastoglobule lipid droplets of plant chloroplasts are believed to be a major orchestrator of adaptive responses to environmental stresses. Yet, understanding of plastoglobule function remains limited to hypothetical models, lacking experimentally validated molecular functions. It is the objective of this project to elucidate the central role of all six plastoglobule-localized ABC1 protein kinases (ABC1Ks) in plastoglobule function. These ABC1Ks are the most abundant enzymes of the plastoglobule and are thought to serve as master regulators of plastoglobule function through phospho-regulation of the plastoglobule proteome. This project will characterize the protein kinase activity of each ABC1K, define the phospho-regulatory network of plastoglobules, dissect the functional relevance of the unique N- and C- terminal flanks of ABC1Ks, and unravel the biological functions of the ABC1Ks. These goals will be accomplished through a series of in vitro kinase assays with heterologously expressed ABC1Ks and phenotypic investigations of knock-out and over-expressor mutant lines, including a large-scale phosphoproteomic and lipidomic study.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.