Stomatal-based systems analysis of water use efficiency

基于气孔的水利用效率系统分析

• 批准号: BB/L001276/1
• 负责人: Michael Blatt
• 金额: $ 53.1万
• 依托单位: University of Glasgow
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2014
• 资助国家: 英国
• 起止时间: 2014 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=BB%2FL001276%2F1
• 关键词: Stomatal; based; systems; analysis; water

Stomata are pores that provide for gaseous exchange across the impermeable cuticle of plant leaves. They open and close to balance the requirement for CO2 entry for photosynthesis against the need to reduce the transpiration of water vapour and prevent leaf drying. Stomatal transpiration is at the centre of a crisis in water availability and crop production that is expected to unfold over the next 20-30 years: globally, agricultural water usage has increased 6-fold in the past 100 years, twice as fast as the human population, and is projected to double again before 2030. Thus stomata represent an important target for breeders interested in manipulating crop performance. Stomatal movements are driven by solute transport - and consequent uptake/loss of water - across the cell membrane of the guard cells which surround the stomatal pore. Significantly, stomatal responses are slow compared to photosynthesis in the face of environmental fluctuations, especially of light. Improving water use efficiency (=amount of carbon fixed in photosynthesis/amount of water transpired) should be possible, without a cost to carbon assimilated in photosynthesis, if the speed of stomatal responses, especially to light, can be enhanced. However, the complexity of guard cell transport and its coupling to gas exchange and transpiration has presented a formidable barrier to systematic reverse-engineering aimed at enhancing stomatal responses through genetic manipulation and other means.Quantitative systems analysis offers an effective approach in silico to exploring the link between microscopic gene function and the macroscopic characteristics of assimilation and transpiration. As a first step to bridging this gap in understanding, we developed previously the OnGuard software for quantitative dynamic modelling of the guard cell. OnGuard models build explicitly on the wealth of molecular, biophysical and kinetic knowledge for guard cell transport and metabolism that drive stomatal movement; they accommodate stomata of different plant species, over the full range of conditions studied in the laboratory to date; and they have been shown to incorporate the real predictive power needed to guide experiments at the cellular and physiological levels that start with molecular manipulations in silico. The next major step towards establishing in silico strategies for crop design, based on our deep knowledge of stomatal guard cells, will be to establish and validate this computational link to incorporate carbon assimilation and water use efficiency at leaf and whole-plant levels.We propose now to develop such a strategy in models of the leaf, and scaling to the crop in the field, that capture CO2 uptake and transpiration. We will build the next-generation OnGuard models that incorporate CO2 uptake and transpiration, and we will incorporate computational statistical methods to accelerate model construction. Most important, the models will provide the essential micro-macro link to connect molecular function with physiological traits of the whole plant in water use and photosynthetic carbon assimilation and will enable scaling to the crop in the field. We will test this second generation of OnGuard models and validate their outputs to examine the longstanding hypothesis that significant erosion in the efficiency of water use by plants arises because of the mismatch in dynamic environmental responses between stomata and photosynthesis. Additionally, we will explore the connection of these traits with oscillations known to occur in stomatal aperture and in the signalling events (e.g. cytosolic-free [Ca2+]) previously documented at the cellular level in single guard cells. All studies will focus on the crop plant Vicia for which there is much data at the single-cell and whole-leaf levels, and on Arabidopsis for which we have mutants with well-defined effects on stomatal kinetics.

气孔是在植物叶子的不渗透角质层之间提供气体交换的孔隙。它们的打开和关闭是为了平衡光合作用二氧化碳进入的需要与减少水蒸气蒸腾和防止叶子干燥的需要。气孔蒸腾是水资源供应和农作物生产危机的核心，预计这一危机将在未来 20-30 年内展开：全球范围内，农业用水量在过去 100 年中增加了 6 倍，是人类用水速度的两倍人口，预计到 2030 年将再次翻倍。因此，气孔代表了对操纵作物性能感兴趣的育种者的重要目标。气孔运动是由溶质运输驱动的 - 以及随之而来的水的吸收/损失 - 穿过气孔周围的保卫细胞的细胞膜。值得注意的是，面对环境波动，尤其是光的波动，气孔反应比光合作用慢。如果可以提高气孔反应速度，特别是对光的反应速度，那么提高水分利用效率（=光合作用中固定的碳量/蒸腾水量）应该是可能的，而不需要光合作用中碳同化的成本。然而，保卫细胞运输的复杂性及其与气体交换和蒸腾作用的耦合，对旨在通过基因操作和其他手段增强气孔反应的系统逆向工程构成了巨大的障碍。定量系统分析提供了一种有效的计算机方法来探索微观基因功能与同化和蒸腾的宏观特征之间的联系。作为弥合这一理解差距的第一步，我们之前开发了用于保卫细胞定量动态建模的 OnGuard 软件。 OnGuard 模型明确建立在丰富的分子、生物物理和动力学知识的基础上，用于驱动气孔运动的保卫细胞运输和新陈代谢；它们适应不同植物物种的气孔，涵盖迄今为止实验室研究的各种条件；事实证明，它们具有指导细胞和生理水平实验所需的真正预测能力，这些实验从计算机分子操作开始。基于我们对气孔保卫细胞的深入了解，建立作物设计计算机策略的下一个主要步骤将是建立并验证这种计算链接，以将碳同化和水分利用效率纳入叶片和整株植物的水平。我们建议现在，我们要在叶子模型中制定这样的策略，并扩展到田间作物，以捕获二氧化碳的吸收和蒸腾作用。我们将构建结合二氧化碳吸收和蒸腾作用的下一代 OnGuard 模型，并将结合计算统计方法来加速模型构建。最重要的是，这些模型将提供必要的微观-宏观联系，将分子功能与整个植物在水分利用和光合碳同化方面的生理特征联系起来，并将能够扩大到田间作物的规模。我们将测试第二代 OnGuard 模型并验证其输出，以检验长期以来的假设，即由于气孔和光合作用之间的动态环境响应不匹配，导致植物用水效率显着下降。此外，我们将探索这些性状与已知发生在气孔孔径和信号事件（例如无胞质[Ca2+]）中的振荡之间的联系，这些振荡先前在单保卫细胞的细胞水平上记录。所有研究都将集中在作物蚕豆上，该作物在单细胞和全叶水平上有大量数据，以及拟南芥，我们拥有对气孔动力学有明确影响的突变体。

项目成果

Light-Driven Chloride Transport Kinetics of Halorhodopsin.

• DOI: 10.1016/j.bpj.2018.06.009
• 发表时间: 2018-07
• 期刊: Biophysical journal
• 影响因子: 3.4
• 作者: Hasin Feroz;Bryan H Ferlez;Cécile Lefoulon;Tingwei Ren;Carol S. Baker;John P. Gajewski;D. J. Lugar;Sandeep Gaudana;P. Butler;Jonas Hühn;M. Lamping;W. Parak;J. Hibberd;C. Kerfeld;N. Smirnoff;M. Blatt;J. Golbeck;Manish Kumar

Clustering of the K+ channel GORK of Arabidopsis parallels its gating by extracellular K+.

• DOI: 10.1111/tpj.12471
• 发表时间: 2014-04
• 期刊: The Plant journal : for cell and molecular biology
• 作者: Eisenach C;Papanatsiou M;Hillert EK;Blatt MR
• 通讯作者: Blatt MR

Exploring emergent properties in cellular homeostasis using OnGuard to model K+ and other ion transport in guard cells.

• DOI: 10.1016/j.jplph.2013.09.014
• 发表时间: 2014-05-15
• 期刊: JOURNAL OF PLANT PHYSIOLOGY
• 影响因子: 4.3
• 作者: Blatt, Michael R.;Wang, Yizhou;Leonhardt, Nathalie;Hills, Adrian
• 通讯作者: Hills, Adrian

What can mechanistic models tell us about guard cells, photosynthesis, and water use efficiency?

• DOI: 10.1016/j.tplants.2021.08.010
• 发表时间: 2022-01-12
• 期刊: TRENDS IN PLANT SCIENCE
• 影响因子: 20.5
• 作者: Blatt, Michael R.;Jezek, Mareike;Hills, Adrian
• 通讯作者: Hills, Adrian

Focus on Water

• DOI: 10.1104/pp.114.900484
• 发表时间: 2014-04-01
• 期刊: PLANT PHYSIOLOGY
• 影响因子: 7.4
• 作者: Blatt, Michael R.;Chaumont, Francois;Farquhar, Graham
• 通讯作者: Farquhar, Graham