EAGER: Breaking the walls down: Understanding the role of cell wall components in root growth regulation under water deficit conditions

渴望：打破细胞壁：了解细胞壁成分在缺水条件下根系生长调节中的作用

• 批准号: 2318661
• 负责人: Priya Voothuluru
• 金额: $ 29.9万
• 依托单位: University of Missouri-Columbia
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-08-01 至 2025-07-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2318661&HistoricalAwards=false
• 关键词: EAGER; Breaking; walls; down; Understanding

The overall goal of this project is to elucidate the changes in cell wall composition and cell wall mechanics that allow maize primary roots to maintain growth under water limited conditions. Limited water availability is a major environmental factor constraining plant development, in turn adversely affecting plant performance and crop yields. One of the prominent responses of plants to water limitation is the maintenance of root growth, enabling access to water from deeper soil profiles. Substantial changes in cell wall composition are implicated in root growth maintenance under water limitation. However, due to technical challenges, the molecular and physiological mechanisms involved in root growth maintenance under water limitation remain unknown. Such understanding is critical for improving crop productivity in normal and stressful environments and for sustainable bioenergy production. This research integrates biochemical and biomechanical information from sub-cellular to organ-level responses of root tissues to decipher the functional role of cell wall components in regulating root growth. Successful completion of these state-of-the-art studies will provide proof-of-concept for quantitative analyses of plant cell walls exhibiting different compositional and functional characteristics. This multi-disciplinary approach will enable the identification of design rules for the interactions of different components within the cell wall matrix and their impacts on plant growth and morphogenesis under normal and stressful environments. The fundamental knowledge and the technological advances developed through this project will ultimately enhance agricultural productivity under normal and stressful environments by allowing predictions about how plants, especially crop plants like maize, will respond to climate change. The project will provide interdisciplinary training and mentoring for a graduate student at the University of Central Florida, an Hispanic-Serving Institution, and at least two undergraduate researchers, contributing to workforce development.Maize primary and nodal roots preferentially maintain growth under water stress conditions, compared to shoot tissues that show growth inhibition. Within the primary root growth zone, the apical region completely maintains cell elongation and growth even under severe water stress, whereas the basal region shows reduced cell elongation and growth deceleration. These spatially differential responses are associated with changes in cell wall yielding properties and potentially changes in cell wall composition. The overall goal of this project is to elucidate the changes in cell wall composition and wall mechanics that enable primary roots to maintain growth under water stress conditions. The specific objectives are to first reveal the differential cell wall compositional changes occurring within the growth zone of maize primary roots grown under water limitation compared to well-watered primary roots, and subsequently to assess the mechano-chemical changes occurring in the cell walls of the growth zone of primary roots under water stress to correlate them with cell wall extensibility and root growth. Integration of cell wall compositional analyses with biochemical and biomechanical studies from sub-cellular to organ-level scales will enable deeper understanding of plant growth under normal and water limited conditions. This multi-scale approach will unveil how components interact within the cell wall matrix and how they impact cell expansion and plant growth under water stress conditions. In the long-term, knowledge from these studies will pave the way to selectively alter cell wall components to promote stress-responsive growth in plants and optimize them for sustainable food and energy production.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.

本项目的总体目标是阐明细胞壁组成和细胞壁力学的变化，使玉米初生根在水分限制条件下保持生长。有限的水资源是制约植物生长的一个主要环境因素，反过来又对植物生长和作物产量产生不利影响。植物对水分限制的一个突出反应是维持根系生长，使其能够从更深的土壤剖面获得水分。细胞壁组成的实质性变化与水分限制下根系生长的维持有关。然而，由于技术上的挑战，参与水分限制下的根生长维持的分子和生理机制仍然未知。这种理解对于在正常和压力环境中提高作物产量以及可持续的生物能源生产至关重要。这项研究整合了从根组织的亚细胞到器官水平反应的生物化学和生物力学信息，以破译细胞壁组分在调节根生长中的功能作用。这些最先进的研究的成功完成将为表现出不同组成和功能特征的植物细胞壁的定量分析提供概念验证。这种多学科的方法将使识别的设计规则的细胞壁基质内的不同成分的相互作用和它们对植物生长和形态发生的影响下正常和压力的环境。通过该项目开发的基础知识和技术进步将最终提高正常和压力环境下的农业生产力，预测植物，特别是玉米等作物将如何应对气候变化。该项目将提供跨学科的培训和指导，在中央佛罗里达，西班牙裔服务机构的大学的研究生，至少有两名本科生的研究人员，有助于劳动力的发展。玉米的初级和节的根优先保持水分胁迫条件下的生长，相比，拍摄组织，显示生长抑制。在主根生长区内，即使在严重的水分胁迫下，顶端区域也完全保持细胞伸长和生长，而基部区域显示细胞伸长和生长减速减少。这些空间差异的反应与细胞壁屈服性质的变化和细胞壁组成的潜在变化有关。本项目的总体目标是阐明细胞壁组成和壁力学的变化，使初级根在水分胁迫条件下保持生长。具体的目标是首先揭示差异细胞壁组成的变化发生在生长区的玉米初生根生长在水分限制下，浇水良好的初生根相比，随后评估的机械力化学变化发生在细胞壁的生长区的初生根在水分胁迫下，将它们与细胞壁的伸展性和根的生长。将细胞壁成分分析与从亚细胞到器官水平的生化和生物力学研究相结合，将使人们能够更深入地了解正常和水分限制条件下的植物生长。这种多尺度方法将揭示组分如何在细胞壁基质内相互作用，以及它们如何在水分胁迫条件下影响细胞扩增和植物生长。从长远来看，从这些研究中获得的知识将为选择性改变细胞壁成分铺平道路，以促进植物的应激反应生长，并优化它们以实现可持续的食品和能源生产。该奖项反映了NSF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。