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.

该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有限的条件下保持生长。有限的可用水量是限制植物发育的主要环境因素，进而对植物性能和作物产量产生不利影响。植物对水分限制的显着反应之一是维持根系生长，从而能够从更深的土壤剖面获取水分。细胞壁组成的显着变化与水分限制下根系生长的维持有关。然而，由于技术挑战，水分限制下根系生长维持的分子和生理机制仍然未知。这种理解对于提高正常和压力环境下的作物生产力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化和生物力学信息，以破译细胞壁成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具有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。这种多学科方法将能够确定细胞壁基质内不同成分相互作用的设计规则，及其在正常和应激环境下对植物生长和形态发生的影响。通过该项目开发的基础知识和技术进步将通过预测植物，特别是玉米等农作物如何应对气候变化，最终提高正常和压力环境下的农业生产力。该项目将为西班牙裔服务机构中佛罗里达大学的一名研究生和至少两名本科生研究人员提供跨学科培训和指导，为劳动力发展做出贡献。与表现出生长抑制的芽组织相比，玉米初生根和节根在水分胁迫条件下优先维持生长。在初生根生长区内，即使在严重的水分胁迫下，顶端区域也能完全维持细胞伸长和生长，而基部区域显示出细胞伸长减少和生长减速。这些空间差异反应与细胞壁产量特性的变化和细胞壁组成的潜在变化相关。该项目的总体目标是阐明细胞壁组成和壁力学的变化，使初生根在水分胁迫条件下保持生长。具体目标是首先揭示与水分充足的初生根相比，在水分限制下生长的玉米初生根生长区内发生的细胞壁成分变化，随后评估水分胁迫下初生根生长区细胞壁发生的机械化学变化，将其与细胞壁延伸性和根生长相关联。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，将有助于更深入地了解正常和缺水条件下的植物生长。这种多尺度方法将揭示细胞壁基质内的成分如何相互作用，以及它们如何在水分胁迫条件下影响细胞扩张和植物生长。从长远来看，这些研究的知识将为有选择地改变细胞壁成分以促进植物的应激反应性生长并优化它们以实现可持续食品和能源生产铺平道路。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。