The N-end rule pathway controls plant response to drought

为了在气候变化的情况下维持不断增长的人口的粮食安全，迫切需要开发用水量更少、对环境压力（特别是干旱）更有耐受性的作物。我们最近在诺丁汉大学和谢菲尔德大学的研究使用实验室模型拟南芥（相当于实验室老鼠的植物）已经确定了对干旱胁迫具有极强耐受性的植物。耐旱植物缺乏识别细胞内特定蛋白质的能力，并通过一种被称为n端规则途径的生化过程将其摧毁。到目前为止，从我们的分析中，我们已经有了一个重要的线索，关于“抗旱蛋白”的身份，它没有被破坏，因此在我们的抗旱植物中是稳定的。我们知道这种蛋白质的一端有氨基酸残基蛋氨酸和半胱氨酸。在这个项目中，我们将确定哪些特定的蛋白质在我们的植物中是稳定的，为我们将来如何使植物更耐旱提供了重要的信息。我们还将发现同样的n端规则抗旱系统是否适用于一种重要的英国作物大麦。在过去的一年里，英国的许多地区都经历了不寻常的长期干旱，其中包括自1910年有记录以来最干旱的12个月。这导致作物歉收严重，2011年的粮食产量受到的影响尤其严重。农民报告说，他们的大麦作物有10%到50%的歉收，而幸存下来的大麦籽粒通常质量很差，只适合作为低价值的动物饲料，而不是用于酿造啤酒。由于这对农民和酿酒商来说都是一个问题，英国大型酿酒公司SABMiller已经同意资助我们的部分研究项目。南非米勒致力于减少他们的用水量，并相信更好地了解大麦对干旱的反应可能有助于他们实现这一目标。我们的研究直接属于英国研究委员会确定的全球粮食安全和环境变化跨委员会优先事项的范围。该项目将有助于解决BBSRC的战略研究重点粮食安全（作物科学），我们与SABMiller的合作将解决建立伙伴关系（与用户合作研究）议程。

In order to maintain food security for a growing population under climate change, there is a pressing need to develop crops that use less water and that are more tolerant to environmental stresses, particularly drought. Our recent research at the Universities of Nottingham and Sheffield using the laboratory model Arabidopsis thaliana (the plant equivalent of a lab-rat) has identified plants that are extremely tolerant to drought stress. The drought tolerant plants lack the ability to recognise particular proteins inside their cells and send them for destruction by a biochemical process called the N-end rule pathway. From our analysis so far, we already have an important clue as to the identity of the 'drought tolerance protein' that is not destroyed and is therefore stabilised in our drought-tolerant plants. We know that this protein has the amino acid residues methionine and cysteine at one end. In this project we shall identify which specific protein(s) are stabilised in our plants providing us with important information on how we could, in the future, make plants more drought-tolerant. We will also find out if the same N-end rule drought tolerance system works in an important UK crop, barley. Many parts of the UK have experienced unusual and extended periods of drought over the past year which has included the driest 12 months since records began in 1910. This has led to a high level of crop failure with 2011 grain yields being particularly affected. Farmers have reported failure of 10% to 50% of their barley crop, and the surviving barley grain has often been of poor quality, only suitable for low value animal feed rather than for beer-making. As this is a problem for both farmers and brewers, SABMiller a major UK brewing company have agreed to fund part of our research project. SABMiller are committed to reducing the amount of water that they use, and believe that a better understanding of how barley responds to drought may help them to achieve this aim.Our research falls directly within the remit of Global Food Security and Living with Environment Change cross-council priorities identified by the UK Research Councils. The project will help to address the BBSRC strategic research priority Food Security (Crop Science) and our collaboration with SABMiller addresses the Building Partnerships (Collaborative Research with Users) agenda.