Molecular mechanisms underlying the optimised circadian clock control of Crassulacean acid metabolism

由于气候变化，世界变得越来越热，越来越干燥，人口迅速增长，据预测，到2050年，我们需要将作物产量提高50 - 70%，才能养活预测的90 - 100亿人口。这种额外的粮食生产必须使用相同的土地和相同或更少的淡水来实现，相对于今天的农业用水。在作物生产力方面取得如此巨大的进步，以巩固本世纪的人类粮食安全，被广泛认为是一项关键的全球重大挑战，需要“跳出框框思考”的突破性创新方法。我们的研究旨在利用自然发生的光合作用的增压适应，称为景天科酸代谢（CAM）。这种适应可以提高植物的水分利用效率，远远超过水稻、小麦或玉米等当今任何主要粮食作物物种的利用效率，而且可能对生物能源和可再生平台化学品的原料作物具有更大的效用。本研究通过对卡氏藻属中CAM模式物种的基因组和转录组进行解码，并开展功能基因组学研究，探讨候选CAM基因的功能，建立将CAM基因工程化改造到C3作物中以提高水分利用效率和光合作用的最小部件列表。该项目将利用我们最近的发现，通过探索CAM中涉及的基因，使用转基因方法来关闭或打开基因，和/或使用报告基因构建体探索基因调控。特别是，我们试图了解内源性生物钟（生物体用于优化其生物化学相对于每日光/暗周期的内部计时器）如何向CAM系统发出信号，以优化分别在黑暗和光照下发生的步骤。这个博士学位将使学生对我们理解与CAM及其最佳时间调节相关的遗传因素做出关键贡献。学生也将成为完成植物转化和所需的详细分子，所产生的转基因品系的生化和生理特性。由于气候变化，世界变得越来越热和干燥，人口迅速增长，据预测，我们将需要将作物产量增加50 - 70到2050年，为了养活预测的90 - 100亿人口。我们的研究旨在利用自然发生的光合作用的增压适应，称为景天科酸代谢（CAM）。这种适应可以提高植物水分利用效率，远远超过当今任何主要粮食作物物种，如水稻，小麦或玉米。本研究通过对卡氏藻属中CAM模式物种的基因组和转录组进行解码，并开展功能基因组学研究，探讨候选CAM基因的功能，建立将CAM基因工程化改造到C3作物中以提高水分利用效率和光合作用的最小部件列表。该项目将利用我们最近的发现，通过探索CAM中涉及的基因，使用转基因方法来关闭或打开基因，和/或使用报告基因构建体探索基因调控。特别是，我们试图了解内源性生物钟（生物体用于优化其生物化学相对于每日光/暗周期的内部计时器）如何向CAM系统发出信号，以优化分别在黑暗和光照下发生的步骤。

The world is getting hotter and drier due to climate change, and the human population is growing rapidly to the extent that it has been predicted that we will need to increase crop yields by 50 - 70 % by 2050 in order to feed the predicted 9 - 10 billion people. This extra food production has to be achieved using the same land and the same or less fresh water relative to the water used by agriculture today. Achieving such dramatic advances in crop productivity to underpin human food security this century is widely regarded as a key global grand challenge that requires ground-breaking, innovative approaches that "think outside the box". Our research aims to leverage a naturally occurring super-charged adaptation of photosynthesis called Crassulacean acid metabolism (CAM). This adaptation can enhance plant water use efficiency well beyond that of any of today's major food crop species such as rice, wheat or maize, and has, perhaps, even greater utility for feedstock crops for bioenergy and renewable platform chemicals. Through decoding the genomes and transcriptomes of model CAM species in the genus Kalanchoë and undertaking functional genomics research to investigate the function of candidate CAM genes, our work is establishing the minimal parts list for engineering CAM into C3 crops to enhance water use efficiency and photosynthesis. This project will leverage our recent discoveries by exploring the genes involved in CAM using transgenic approaches to switch genes off or on, and/ or explore gene regulation using reporter gene constructs. In particular, we seek to understand how the endogenous circadian clock (the internal timekeeper that organisms use to optimise their biochemistry relative to the daily light/ dark cycle) signals to the CAM system in order to optimize the steps that occur separately both in the dark and the light. This PhD will allow the student to make a key contribution to our understanding of the genetic elements associated with CAM and its optimal temporal regulation. The student will also become accomplished in plant transformation and the techniques required for the detailed molecular, biochemical and physiological characterisation of the generated transgenic lines.The world is getting hotter and drier due to climate change and the human population is growing rapidly to the extent that it has been predicted that we will need to increase crop yields by 50 - 70 % by 2050 in order to feed the predicted 9 - 10 billion people. Our research aims to leverage a naturally occurring super-charged adaptation of photosynthesis called Crassulacean acid metabolism (CAM). This adaptation can enhance plant water use efficiency well beyond that of any of today's major food crop species such as rice, wheat or maize. Through decoding the genomes and transcriptomes of model CAM species in the genus Kalanchoë and undertaking functional genomics research to investigate the function of candidate CAM genes, our work is establishing the minimal parts list for engineering CAM into C3 crops to enhance water use efficiency and photosynthesis. This project will leverage our recent discoveries by exploring the genes involved in CAM using transgenic approaches to switch genes off or on, and/ or explore gene regulation using reporter gene constructs. In particular, we seek to understand how the endogenous circadian clock (the internal timekeeper that organisms use to optimise their biochemistry relative to the daily light/ dark cycle) signals to the CAM system in order to optimize the steps that occur separately both in the dark and the light.