Annexin1-mediated calcium signalling controls plant responses to ozone

臭氧作为地面污染物的水平威胁着农作物和牧场的生产力。欧洲每年的农作物损失价值数十亿欧元。臭氧“插曲”的频率(当当地条件在生长季节促进臭氧显著上升时)将会增加。臭氧会减少地上部(和根部)的生长，导致叶片脱落，并影响谷物的发育。臭氧还会加剧干旱对植物的影响。由于干旱影响了英国的大片地区，必须了解植物如何抵御臭氧，以应对这个问题。植物对臭氧的反应是通过产生一种内部信号，导致表达的基因发生变化。它还可能导致细胞死亡。钙的增加是这一信号的重要组成部分。我们发现了一种突变植物，它不能产生这种钙信号。通过将突变体与其未突变的野生型进行比较，我们可以利用突变体作为一种工具，揭示从遗传到整个植物水平对臭氧的响应发生的变化。我们知道突变体中缺失的蛋白质，并将在关键类型的细胞中测试其功能。我们还将评估它对植物调节其水和气体关系以及在臭氧胁迫下单独生长或与干旱结合的能力的重要性。这些比较研究还将确定可能在抗臭氧作物育种计划中使用的基因。

Levels of ozone as a ground-level pollutant threaten crop and pasture productivity. European crop losses are worth several billion Euros annually. The frequency of ozone "episodes" (when local conditions promote significant ozone elevation during the growing season) is set to increase. Ozone reduces shoot (and root) growth, causes leaf loss and affects grain development. Ozone can also exacerbate the effects of drought on plants. With drought affecting large areas of the UK, how plants defend against ozone must be understood to combat this problem. Plants respond to ozone by generating an internal signal that causes changes in the genes that are expressed. It can also lead to cell death. An increase in calcium is an important component of this signal. We have discovered a mutant plant that cannot generate this calcium signal. By comparing the mutant with its non-mutated wild type, we can use the mutant as a tool with which to reveal the changes that occur in response to ozone from the genetic to whole plant level. We know the protein that is missing in the mutant and will test for its function in critical types of cell. We will also assess its importance to a plant's ability to regulate its water and gas relations and grow under ozone stress alone or combined with drought. These comparative studies will also identify genes likely to be of use in breeding programmes for ozone-resistant crops.