Molecular characterisation of an ADP-dependent regulatory protein

ADP 依赖性调节蛋白的分子表征

• 批准号: BB/G004145/1
• 负责人: Michael Webb
• 金额: $ 41.62万
• 依托单位: University of Leeds
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2008
• 资助国家: 英国
• 起止时间: 2008 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=BB%2FG004145%2F1
• 关键词: Molecular; characterisation; ADP; dependent; regulatory; Molecular; characterisation; ADP; dependent; regulatory

Conversion of carbon dioxide to sugars by plants is essential to life on earth. In the majority of plants this process competes with non-productive reaction with oxygen. One group of plants, the C4 plants, have developed a strategy to avoid this: this strategy allows the plants to survive in hot, dry and arid conditions which would not otherwise be viable for plant growth. These plants include the common crop plants, maize and sugarcane. Research is presently underway to determine if this pathway can be engineered into other plants to generate hardier crop plants and this research will feed into this objective. Our research addresses how one part of this alternative strategy of making sugars is controlled. In particular, we are interested in how an unusual protein acts to switch off the pathway in the dark. The protein, pyruvate,orthophosphate dikinase (PPDK) regulatory protein, or PDRP for short, inactivates another protein, PPDK, thereby preventing the plant from making the compound phosphoenolpyruvate from pyruvate. This prevents the plant from 'fixing' carbon dioxide into sugars in the dark (when there is no light to provide energy via photosynthesis). The regulatory protein, PDRP, can perform this vital function because it is dependent upon the presence of its substrate, ADP, for activity. This accumulates in the dark as a direct result of photosynthesis shutting down. We are interested in the details of the way in which the regulatory protein uses this molecule to inactivate PPDK. We will develop new ways to study this process and make mimics of the target which will help us further unravel the precise manner in which it occurs. The target protein is inactivated because a phosphate group is transferred from the substrate ADP to the protein, thereby blocking the part of PPDK required to perform its normal function. It is worth noting that using this particular molecule, adenine diphosphate (ADP), to perform this reaction is highly unusual, normally adenine triphosphate (ATP) is used instead.

将二氧化碳转化为植物对糖的糖对于地球上的生命至关重要。在大多数植物中，这个过程与氧气竞争非生产性反应。一组植物，即C4植物，已经制定了一种避免这种情况的策略：该策略使植物可以在炎热，干燥和干旱的条件下生存，否则这些策略对植物的生长不可行。这些植物包括常见的作物植物，玉米和甘蔗。目前正在进行研究，以确定该途径是否可以在其他植物中设计为产生更艰苦的作物植物，这项研究将符合这一目标。我们的研究介绍了如何控制这种制造糖的替代策略的一部分。特别是，我们对不寻常的蛋白质如何在黑暗中关闭路径感兴趣。蛋白质，丙酮酸，正磷酸二基酶（PPDK）调节蛋白或pDRP短，使另一种蛋白质使PPDK灭活，从而阻止了植物从丙酮酸中制造复合磷酸烯醇丙酮酸。这样可以防止植物在黑暗中“固定”二氧化碳成糖（当没有光合通过光合作用提供能量时）。调节蛋白PDRP可以执行此重要功能，因为它取决于其底物ADP的存在。由于光合作用关闭的直接结果，这在黑暗中积聚。我们对调节蛋白使用该分子灭活PPDK的方式感兴趣。我们将开发新的方法来研究这一过程并制作模仿目标，这将帮助我们进一步揭示其发生的精确方式。靶蛋白被灭活，因为磷酸基团从底物ADP转移到蛋白质，从而阻止了执行其正常功能所需的PPDK部分。值得注意的是，使用这种特定的分子腺嘌呤二磷酸（ADP）进行此反应是高度不寻常的，通常使用三磷酸腺嘌呤（ATP）。