Regulation of nutrient-stress signaling through the plant vascular system

通过植物维管系统调节营养胁迫信号

• 批准号: RGPIN-2019-04421
• 负责人: Ham, ByungKook
• 金额: $ 2.4万
• 依托单位: University of Saskatchewan
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=745730
• 关键词: Regulation; nutrient; stress; signaling; through

Application of nitrogen/phosphorous/potassium fertilizers enables us to achieve enhanced productivity in agriculture. Modern breeding program has sought to develop crop species to increase nutrient use efficiency for achieving sustainable crop yield and ensuring global food security under reduced/limited fertilizer inputs. Once plants face limitations in mineral nutrient availability, roots are usually the first tissues to respond to these stress conditions which are sensed by root-localized mechanisms; the root translates these stresses into the root-derived signals that are transported through the xylem to communicate the challenging conditions to the shoot. Delivery of these signals to vegetative tissues elicits production of specific output signals that enter the phloem to carry commands from the shoot, back to the root, to integrate the requirements for developmental and physiological processes. Although there is clear evidence in the literature that the plant vascular system functions as the effective communication pathway, much remains to be discovered in terms of the signaling components in these pathways and how they function in mineral nutrient homeostasis. The long-term goal of my research program is to verify molecular regulatory mechanisms in nutrient-stress signaling, mediated by the root-shoot communication through the plant vascular system, especially the phloem. To advance the knowledge of the phloem function in long-distance nutrient-stress signaling, I outline here a strategy to identify regulatory mechanisms involved in integrating nutrient homeostasis by phloem-mediated long-distance signaling molecules. Limited information is available on the role of phloem mobile molecules in nutrient-stress signaling, and the utilization of functional genomics, bioinformatics, physiological and protein biochemistry studies will be involved to address the following objectives: 1) Determine which nutrient-stress responsive phloem proteins traffic to the root and shoot apex, 2) Characterize mobile transcription factors which function in gene regulatory pathways at the sites the signals are delivered to responsive sink tissues, 3) Validate the role of these identified phloem-mobile signaling molecules in plant developmental adaptive responses to nutrient-stress conditions. The studies described in this proposal will provide increased understanding and new insights into molecular regulatory mechanisms that serve in nutrient uptake and utilization in plants, mediated by phloem-based systems. This knowledge would offer potential gene targets and a basis for breeding programs aimed at enhancing nutrient use efficiency in crop plants.

施用氮/磷/钾肥使我们能够提高农业生产力。现代育种计划寻求开发作物品种，以提高养分利用效率，从而在减少/限制肥料投入的情况下实现可持续作物产量并确保全球粮食安全。一旦植物面临矿物营养可用性的限制，根通常是第一个对这些胁迫条件做出反应的组织，这些胁迫条件由根定位机制感知;根将这些胁迫转化为根源信号，这些信号通过木质部传输，以将挑战性条件传达给芽。将这些信号传递到营养组织，可以产生特定的输出信号，这些信号进入韧皮部，将命令从芽传回根，以整合发育和生理过程的要求。虽然在文献中有明确的证据表明植物维管系统作为有效的通信途径发挥作用，但在这些途径中的信号传导组分以及它们如何在矿物质营养体内平衡中发挥作用方面仍有许多有待发现。我的研究计划的长期目标是验证营养胁迫信号的分子调控机制，通过植物维管系统，特别是韧皮部的根-茎通讯介导。为了推进知识的韧皮部功能在长距离营养胁迫信号，我在这里概述了一个策略，以确定参与整合营养稳态的韧皮部介导的长距离信号分子的监管机制。关于韧皮部移动的分子在营养胁迫信号传导中的作用的信息有限，将利用功能基因组学、生物信息学、生理学和蛋白质生物化学研究来解决以下目标：1）确定哪些营养胁迫响应性韧皮部蛋白质运输到根和芽尖，2）表征移动的转录因子，所述转录因子在基因调控途径中在信号被递送到响应性接收组织的位点处起作用，3）阐明这些韧皮部移动信号分子在植物发育适应性反应中的作用。本提案中描述的研究将为植物营养吸收和利用的分子调控机制提供更多的理解和新的见解，这些机制由韧皮部系统介导。这些知识将提供潜在的基因靶点，并为旨在提高作物养分利用效率的育种计划提供基础。