The control of specificity in guard cell ROS-based signalling

基于 ROS 的保卫细胞信号传导的特异性控制

• 批准号: BB/N001168/1
• 负责人: Alistair Hetherington
• 金额: $ 52.13万
• 依托单位: University of Bristol
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2016
• 资助国家: 英国
• 起止时间: 2016 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=BB%2FN001168%2F1
• 关键词: control; specificity; guard; cell; ROS

Over the millennia plants have evolved mechanisms that allow then to adapt to changing environmental conditions. At the heart of these responses are systems that enable plants to detect changes in their environment and then to formulate the appropriate response to the changed conditions. At the level of the single cell changes are detected by receptors and then a complex intracellular machinery is responsible for the elicitation of the appropriate intracellular response. This process is known as stimulus-response coupling (or intracellular signalling). At the heart of this machinery are Reactive Oxygen Species (ROS). When a cell reacts to an external stimulus the concentration of the ROS inside the cell increases. This acts as an intermediate, or trigger, leading to the generation of the final response. The ubiquity of ROS as intermediaries involved in the responses to a plethora of different stimuli raises an important question and this is; how can the increase in ROS elicit specific responses? This nature of the problem can be readily understood by considering one example.Stomata are pores on the surfaces of leaves that open and close in response to changing environmental conditions. The stomatal pore is formed by two guard cells. When these shrink the pore closes whereas swelling results in opening. Stomata are important because they control carbon dioxide uptake and water loss. In guard cells stimuli that bring about swelling (opening) or closure (shrinking) both use intracellular signalling pathways that involve an increase in ROS. How does this work? Unravelling how response specificity is controlled in a single cell is one of the big and unresolved questions in plant cell signalling. Previously making measurements of ROS inside cells has been problematic, however in this application we are making use of step-change advances in technology developed in one of our labs to provide an unprecedented understanding of ROS dynamics in single cells. We believe that we have an international lead in this area, accordingly this is a very timely application, bringing together the new technology from Exeter and the biological system (stomata) in Bristol to find answers to a major unresolved question. Our hypothesis, backed by our preliminary data, is that different stimuli generate unique patterns of ROS inside cells. We call these ROS signatures. These are then decoded by the intracellular machinery inside the cell to produce the specific response. In this application, we will use our new technology to test this hypothesis. We will also find out the origin(s) of the ROS increase and whether these differ between stimuli and we will also investigate what parts of the stomatal opening and closure mechanism are controlled by increases in ROS. Finally we will investigate the interaction between another intracellular signal (calcium) to reveal the extent to which response specificity is controlled by the interaction of ROS and Ca signalling pathways.

几千年来，植物进化出了适应不断变化的环境条件的机制。这些反应的核心是一些系统，这些系统使植物能够检测到环境的变化，然后对变化的条件做出适当的反应。在单细胞水平上，受体检测到变化，然后一个复杂的细胞内机制负责引发适当的细胞内反应。这个过程被称为刺激-反应耦合（或细胞内信号传导）。这个机制的核心是活性氧（ROS）。当细胞对外部刺激产生反应时，细胞内ROS的浓度增加。这是导致最终响应生成的中间过程或触发器。无处不在的活性氧作为中介参与对大量不同刺激的反应提出了一个重要的问题，这是；活性氧的增加是如何引起特异性反应的？考虑一个例子就可以很容易地理解这个问题的性质。气孔是叶子表面的气孔，它们根据环境条件的变化而打开和关闭。气孔由两个保卫细胞组成。当这些收缩时，毛孔会关闭，而肿胀则会打开。气孔很重要，因为它们控制着二氧化碳的吸收和水分的流失。在保护细胞中，引起肿胀（打开）或关闭（收缩）的刺激都使用涉及ROS增加的细胞内信号通路。这是如何工作的呢？揭示如何在单个细胞中控制反应特异性是植物细胞信号传导中尚未解决的重大问题之一。以前测量细胞内的活性氧是有问题的，然而在这个应用中，我们正在利用我们的一个实验室开发的技术的阶跃变化进步，为单细胞中的活性氧动力学提供前所未有的理解。我们相信我们在这一领域处于国际领先地位，因此这是一个非常及时的应用，将埃克塞特大学的新技术和布里斯托尔的生物系统（气孔）结合起来，寻找一个未解决的主要问题的答案。根据我们的初步数据，我们的假设是，不同的刺激会在细胞内产生独特的活性氧模式。我们称之为ROS签名。然后，这些信号被细胞内的细胞机制解码，从而产生特定的反应。在这个应用程序中，我们将使用我们的新技术来测试这个假设。我们还将发现ROS增加的来源以及这些刺激是否不同，我们还将研究气孔打开和关闭机制的哪些部分受ROS增加的控制。最后，我们将研究另一种细胞内信号（钙）之间的相互作用，以揭示ROS和Ca信号通路相互作用控制应答特异性的程度。

项目成果

Actin filament reorganisation controlled by the SCAR/WAVE complex mediates stomatal response to darkness.

由 SCAR/WAVE 复合物控制的肌动蛋白丝重组介导气孔对黑暗的反应

• DOI: 10.1111/nph.14655
• 发表时间: 2017-08
• 期刊: The New phytologist
• 作者: Isner JC;Xu Z;Costa JM;Monnet F;Batstone T;Ou X;Deeks MJ;Genty B;Jiang K;Hetherington AM
• 通讯作者: Hetherington AM

The Breakdown of Stored Triacylglycerols Is Required during Light-Induced Stomatal Opening.

• DOI: 10.1016/j.cub.2016.01.019
• 发表时间: 2016-03-07
• 期刊: Current biology : CB
• 作者: McLachlan DH;Lan J;Geilfus CM;Dodd AN;Larson T;Baker A;Hõrak H;Kollist H;He Z;Graham I;Mickelbart MV;Hetherington AM
• 通讯作者: Hetherington AM

New tools for monitoring hydrogen peroxide in Arabidopsis.

监测拟南芥过氧化氢的新工具。

• DOI: 10.1111/nph.15616
• 发表时间: 2019
• 期刊: The New phytologist
• 作者: McLachlan DH