Selective chemical regulation of plant metabolism with herbicide safeners

除草剂安全剂对植物代谢的选择性化学调节

• 批准号: BB/D005620/1
• 负责人: Robert Edwards
• 金额: $ 48.68万
• 依托单位: Durham University
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2006
• 资助国家: 英国
• 起止时间: 2006 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=BB%2FD005620%2F1
• 关键词: Selective; chemical; regulation; plant; metabolism

Safeners are used in conjunction with herbicides in major cereal crops such as wheat, maize and rice to enhance their selective weed control. This is achieved by the safeners acting to increase the expression of herbicide detoxifying proteins by up-regulating the expression of the respective genes in the crop. Recently, we have determined that safeners work in a species specific manner, with each crop responding to a specific class of safener chemistry. We have also determined that the effects of safeners are not restricted to herbicide detoxifying proteins, but extend to a subtle modification of endogenous plant metabolism, notably through altering the production of phenolics and thiol antioxidants. Safeners are therefore bioactive synthetic compounds which are able to selectively reprogramme elements of plant metabolism which are important in counteracting stress caused by chemicals and/or oxidative damage. While the mechanism of safener action is partly understood at the level of the metabolic responses, nothing is known as to how these synthetic chemicals are recognised by plants to initiate specific cellular signalling events. Based on chemical principles, we propose that modern safeners can be grouped into three major classes of reactivity, all of which will lead to the selective covalent modification of reactive residues on the surface of proteins. We propose that such modification of regulatory proteins causes changes in their activity or interactions which initiate signalling pathways leading to the selective activation of genes encoding antioxidant proteins. The objectives of this programme are to use a combination of synthetic chemistry and biochemistry to identify which signalling-proteins become selectively labelled with safeners . This will entail synthesising safeners labelled with recognition tags and then using these 'chemical hooks' to identify the proteins targeted, thereby identifying how these chemical selectively intervene in plant biochemistry. We will concentrate our efforts on identifying these initial binding events in the model plant species Arabidopsis thaliana, which uniquely among the plants we have studied is selectively responsive to all three classes of safener chemistry. Using different synthetic strategies, the chemical probes will be designed to work in protein extracts and in whole plants, with the tagged proteins then identified from their sequence using methods based on mass spectrometry. As part of the programme we will confirm the roles of these proteins in safener-recognition in Arabidopsis by determining the effect of knocking-out their expression on their responses to the three chemistries under test. We will also determine whether or not similar proteins become labelled in cereals to confirm our results in agriculturally important species and develop chemical variants of existing safeners to determine how this affects their selective enhancement of antioxidant responses in Arabidopsis and the crop species. At the conclusion of our interdisciplinary programme we will have determined for the first time how an important group of agrochemicals exert their selective action in plants. Defining their site of action has important implications in identifying new generations of safeners with improved activities to ensure the future efficient and sustainable use of herbicides in crop protection. In addition, understanding how safeners work will allow us to extend their use in promoting resistance to chemical and oxidative stress in other plants which has potential for applications in bioremediating contaminated land.

安全剂与除草剂一起用于主要谷类作物，如小麦、玉米和水稻，以加强其选择性杂草控制。这是通过安全剂通过上调作物中相应基因的表达来增加除草剂解毒蛋白的表达来实现的。最近，我们已经确定，安全剂的工作在一个物种的具体方式，每种作物响应一类特定的安全化学。我们还确定，安全剂的作用不仅限于除草剂解毒蛋白，而且还延伸到内源性植物代谢的微妙修饰，特别是通过改变酚类和硫醇抗氧化剂的产生。因此，安全剂是生物活性合成化合物，其能够选择性地重编程植物代谢的元素，所述元素在抵消由化学品和/或氧化损伤引起的胁迫中是重要的。虽然安全剂作用的机制在代谢反应的水平上得到了部分理解，但对于这些合成化学物质如何被植物识别以启动特定的细胞信号事件却一无所知。基于化学原理，我们提出，现代安全剂可以分为三个主要类别的反应性，所有这些都将导致选择性共价修饰蛋白质表面上的反应残基。我们建议，这种修饰的调节蛋白引起的变化，其活性或相互作用，启动信号通路，导致选择性激活的基因编码的抗氧化蛋白。该计划的目标是使用合成化学和生物化学的组合，以确定哪些信号蛋白质成为选择性标记的安全剂。这将需要合成标记有识别标签的安全剂，然后使用这些“化学挂钩”来识别目标蛋白质，从而确定这些化学物质如何选择性地干预植物生物化学。我们将集中我们的努力，在模式植物物种拟南芥，其中唯一的植物，我们已经研究了选择性地响应所有三类安全剂化学识别这些初始的结合事件。使用不同的合成策略，化学探针将被设计成在蛋白质提取物和整个植物中工作，然后使用基于质谱的方法从其序列中识别标记的蛋白质。作为该计划的一部分，我们将通过确定敲除它们的表达对它们对测试中的三种化学物质的响应的影响来确认这些蛋白质在拟南芥中的安全剂识别中的作用。我们还将确定类似的蛋白质是否在谷物中被标记，以确认我们在农业重要物种中的结果，并开发现有安全剂的化学变体，以确定这如何影响它们在拟南芥和作物物种中选择性增强抗氧化反应。在我们的跨学科计划结束时，我们将首次确定一组重要的农用化学品如何在植物中发挥其选择性作用。确定它们的作用位点对于确定具有改进活性的新一代安全剂以确保未来除草剂在作物保护中的有效和可持续使用具有重要意义。此外，了解安全剂的工作原理将使我们能够扩展其在促进其他植物对化学和氧化胁迫的抗性方面的用途，这些植物在生物修复污染土地方面具有应用潜力。

项目成果

Substrate specificity and safener inducibility of the plant UDP-glucose-dependent family 1 glycosyltransferase super-family.

植物UDP-葡萄糖依赖性家族1糖基转移酶超级家族的底物特异性和保险剂诱导性。

• DOI: 10.1111/pbi.12775
• 发表时间: 2018-01
• 期刊: Plant biotechnology journal
• 影响因子: 13.8
• 作者: Brazier-Hicks M;Gershater M;Dixon D;Edwards R
• 通讯作者: Edwards R

Testing a chemical series inspired by plant stress oxylipin signalling agents for herbicide safening activity.

• DOI: 10.1002/ps.4859
• 发表时间: 2018-04
• 期刊: Pest management science
• 影响因子: 4.1
• 作者: Brazier-Hicks M;Knight KM;Sellars JD;Steel PG;Edwards R
• 通讯作者: Edwards R