MLO Signaling in Polarized Plasma Membrane Domains

人类已经利用植物的力量，通过授粉的直接产物种子提供大部分卡路里。 植物扎根在原地，因此在自然界中不断受到生物和非生物胁迫的攻击，同时也努力生长和繁殖。 随着世界人口在不断变化的气候中继续增长，确保粮食安全的能力取决于更好地了解植物细胞如何对环境信号做出适当反应。该项目使用授粉和尖端生长细胞作为模型系统，用于解剖植物细胞如何感知来自其他细胞的信号，并调整其反应以促进有益的相互作用并阻止有害的相互作用。这项研究有可能影响社会，因为如果全球气候变化以目前的速度继续下去，植物将面临极端环境，从而导致新的方法来增强有益的植物-生物相互作用。除了通过本科生、研究生和博士后的直接参与来培养下一代科学家外，该项目还将通过在市中心社区中心开展的暑期教育推广和指导计划，提高STEM参与率，并在高中阶段加强代表性不足的少数民族的教育。在感知和反应入侵生物体分泌的外部信号或试图入侵导致的细胞壁扰动方面发挥关键作用。已提出FERONIA（FER）和相关RLK是细胞外扰动的传感器，其触发导致与入侵细胞通信的信号转导级联。在授粉中，FER信号传导的一个结果是信号介导的MLO蛋白NORTIA向雌性配子体助细胞中的极化膜结构域的运输。FER介导的MLO蛋白向离散极性膜结构域的运输可能是一种机制，可以提高细胞外反应的体积。然而，知识是缺乏在何种程度上MLO蛋白作为放大器的FER信号在其他部分的植物。本项目的总体目标是了解RLK信号传导与MLO积累之间的联系以及极化膜结构域的功能。中心假设是FER信号到细胞外空间的MLO放大是RLK调节极化膜结构域处的植物-生物相互作用和极化细胞扩增中的常见机制，并且用于调节细胞对外部信号的响应。总体目标将通过三个具体目标来实现：1）测试FER/MLO信号传导模块在植物-生物相互作用和尖端生长细胞中的保守性; 2）确定FER和MLO活性在极化膜结构域中的交叉;和3）鉴定在极化膜结构域中参与MLO功能的新蛋白质。该奖项反映了NSF的法定使命，并被认为值得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。

Humans have harnessed the power of plants to provide the bulk of their calories through seeds which are a direct product of pollination. Plants are rooted in place and are therefore continually assaulted by both biotic and abiotic stressors in nature while also striving to grow and reproduce. As the world population continues to grow in a changing climate, the ability to ensure food security relies on a better understanding of how plant cells make the appropriate response to signals from their environment. This project uses pollination and tip-growing cells as model systems for dissecting how plant cells perceive signals from other cells and scale their responses to promote beneficial interactions and discourage harmful interactions. This research has the potential to impact society by leading to new approaches for enhancing beneficial plant-biotic interactions in the extreme environments that plants will face if global climate change continues at its current pace. In addition to training the next generation of scientists through direct participation of undergraduates, graduate students, and a postdoc, this project will also enhance STEM participation and education of underrepresented minorities at the high school level through a summer educational outreach and mentoring program at an inner city community center.Receptor-like kinases (RLKs) play key roles in perceiving and reacting to external signals secreted from an invading organism or cell wall perturbations that result from attempted invasions. FERONIA (FER) and related RLKs have been proposed to be sensors of extracellular perturbations that trigger a signal transduction cascade that results in communication with the invading cell. In pollination, one outcome of FER signaling is the signal-mediated trafficking of the MLO protein NORTIA to a polarized membrane domain in the synergid cells of the female gametophyte. FER-mediated trafficking of MLO proteins to discrete polar membrane domains may act as a mechanism to turn up the volume on the extracellular response. However, knowledge is lacking on the extent to which MLO proteins act as amplifiers of FER signaling in other parts of the plant. The overall objective of this project is to understand the link between RLK signaling and MLO accumulation and function at polarized membrane domains. The central hypothesis is that MLO amplification of FER signals to the extracellular space is a common mechanism in RLK regulation of both plant-biotic interactions at polarized membrane domains and polarized cell expansion and acts to modulate the cellular response to external signals. The overall objective will be met through three specific aims: 1) testing conservation of the FER/MLO signaling module in plant-biotic interactions and tip-growing cells; 2) determining the intersection of FER and MLO activities in polarized membrane domains; and 3) identifying new proteins involved in MLO function in polarized membrane domains.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.