RESEARCH-PGR: Cycling to low-temperature tolerance

每年非季节性的寒流造成农作物的重大损失，影响全球粮食安全并限制种植范围。该项目的重点是了解如何使高粱这种对干旱和高温高度耐受的低投入作物对低温更具适应力。从植物的自然生物钟及其与耐寒基因的联系中汲取灵感，在Panicoid草（高粱和玉米所属的植物家族）中探索了对低温耐受性至关重要的转录物、脂质和代谢物的每日波动。提高高粱的低温耐受性可以提高美国大平原的农业可持续性，减轻非季节性寒冷对作物产量的影响。此外，目前提高作物低温耐受性的努力是以牺牲其整体健康为代价的。该项目通过探索植物对温度变化反应的每日节律，挑战了测量和设计作物低温耐受性的传统方法。它有可能重塑如何理解和改造多种作物的耐寒性。为了提高公众对植物行为随日常节奏变化的认识，将与内布拉斯加州立博物馆合作创建一个互动展览，展示植物的昼夜行为及其与低温耐受性的联系。该展览通过巡回展示的方式到达内布拉斯加州的农村学校，旨在向公众宣传这些科学发现对农业和粮食安全的重要性。该项目的长期目标是确定通过节律调节来降低与提高高粱耐寒性相关的健身成本的方法。为了实现这一点，高粱和近遗传关系的谷子，表现出更大的耐冷性之间进行了比较分析。主要的假设驱动的研究是双重的：1）关键的节奏转录和代谢物的鉴定在Panicoid草的耐寒性仍然是不完整的，和2）与耐寒机制相关的健身成本可以抵消通过节奏表达。这些假设得到了初步数据的支持，并通过两个目标进行了测试。首先，确定新的转录本和脂质和可溶性代谢物的关键冷耐受性的节律性反应冷。在初步调查期间，在Panicoid草的转录本和脂质丰度中观察到强烈的节律性，该目标使用多个组学和节律性分析的组合来揭示以前未被识别的影响低温耐受性的代谢和转录模块。鉴定的模块调节子将在拟南芥中表达并测试低温耐受性作为概念验证。第二，确定低温耐受性的时钟控制程度并识别启动子工具。高粱的生物钟功能在遗传上被破坏，谷子的生物钟功能在持续光照下被破坏，以评估它们对低温耐受性的影响。来自耐寒谷子的潜在节律启动子也将在易感高粱物种中进行测试，以建立耐受性工程的工具。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。

Unseasonal cold spells annually cause significant losses in crops, impacting global food security and constraining growing ranges. This project focuses on understanding how sorghum, a low-input crop highly tolerant to drought and heat, can be made more resilient to low temperatures. Drawing inspiration from the natural circadian clock of plants and its connections to cold tolerance genes, daily fluctuations in transcripts, lipids, and metabolites crucial for low temperature tolerance are explored in Panicoid grasses, the plant family to which sorghum and maize belong. Improving sorghum's low temperature tolerance could enhance agricultural sustainability in the U.S. Great Plains, mitigating the impact of unseasonal cold spells on crop yields. Additionally, current efforts to enhance low-temperature tolerance in crops comes at a cost to their overall health. This project challenges traditional approaches to measuring and engineering low temperature tolerance in crops, by exploring the daily rhythms of plant responses to temperature changes. It has the potential to reshape how cold tolerance is understood and engineered in multiple crops. To raise public awareness of plant behaviors that change with daily rhythms, an interactive exhibit showcasing plant diurnal behaviors and their connection to low temperature tolerance will be created in collaboration with the Nebraska State Museum. This exhibit, reaching Nebraskan rural schools through a traveling display, aims to inform and engage the public in the importance of these scientific discoveries for agriculture and food security.The long-term goal of this project is to identify methods to mitigate fitness costs associated with increasing cold tolerance of sorghum through rhythmic regulation. To achieve this, a comparative analysis is conducted between sorghum and close genetic relative foxtail millet, which exhibits greater cold tolerance. The primary hypotheses driving the research are twofold: 1) The identification of key rhythmic transcripts and metabolites essential for cold tolerance in Panicoid grasses remains incomplete, and 2) The fitness cost associated with cold tolerance mechanisms can be counteracted through rhythmic expression. These hypotheses are supported by preliminary data and tested through two objectives. First, identify novel transcripts and lipid and soluble metabolites critical to cold tolerance by their rhythmic response to cold. Building upon strong rhythmicity observed in transcript and lipid abundances in Panicoid grasses during preliminary investigations, this objective uses a combination of multiple omics and rhythmicity analyses to reveal previously unrecognized metabolic and transcriptional modules influencing low-temperature tolerance. Identified module regulators will be expressed and tested for low-temperature tolerance in Arabidopsis as a proof of concept. Second, determine the extent of clock control of low temperature tolerance and identify promoter tools. Clock function is disrupted genetically in sorghum and by continuous light exposure in foxtail millet to assess their impact on low-temperature tolerance. Potentially rhythmic promoters from the cold-tolerant foxtail millet will also be tested in the susceptible sorghum species to establish tools for tolerance engineering.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.