Bilateral NSF/BIO-BBSRC: Development of the Grass Leaf

开花植物表现出两种主要的生长策略。一种(称为双子叶策略)是让植物的生长顶端向上攀升，在它下面产生一根细长的茎。另一种策略(称为单子叶策略)是让生长的顶端保持在植株的底部，并产生一系列的叶子，这些叶子从植株上方升起，然后在植株周围生长。后一种单子叶植物策略的优点是在植物的大部分生命周期中保护植物根部的生长顶端。它使牧草能够在大范围的放牧中生存下来，这也是小麦、玉米和水稻等植物使用的生长策略。尽管它被具有生态和农业重要性的植物所利用，但这种单子叶植物的策略并没有得到很好的理解。在这个项目中，一个由美国(加州大学伯克利分校)和英国(John Innes Centre)研究人员组成的合作团队将使用包括高分辨率成像和计算方法在内的工具组合来测试开发可预测和可测试模型的机制。这些模型将描述单子叶的生长和形状变化的过程。由于叶片的位置对植物进行光合作用所能获得的光量有影响，这项工作可能会对作物产量产生重大影响。生物技术行业将从这项工作中受益，因为他们对组织发育所涉及的过程有了更基本的了解。调查人员将通过开展动手培训活动、YouTube视频和更传统的传播研究成果的方法，积极参与各级教育，包括K-12和公共教育。计算模型已经导致了单子叶发育的初步假设。一个关键的想法是，生长是由一个极场来定向的，这类似于磁场可以用来确定导航方向的方式。观察到的单子叶的生长和形状变化可以用极场和它所指向的生长速率模式的简单变化来解释。这个项目的目的是测试和进一步建立这个模型，并使用玉米单子叶系统(具有发达的遗传学和相关技术的优势)来确定模型预测的极场和生长率是否正确。通过查看突出推定的极性场的标记，并通过确定叶片不同区域的生长速度，可以检验该模型的预测。模型还将通过分析突变来测试，在突变中，关键的发育转变被扰乱。这些研究将通过编写自动提取相关措施的计算机程序来实现量化。还将开发新的计算方法并将其应用于该系统，以便在不同的层面上理解过程，即从细胞到组织的规模。这项美英合作项目得到了美国国家科学基金会和英国生物技术和生物科学研究委员会的支持。

Flowering plants exhibit two major growth strategies. One (called the dicot strategy) is for the growing tip of the plant to climb upward by producing an elongating stem below it. The alternative strategy (termed the monocot strategy) is for the growing tip to stay protected at the base of the plant and produce a series of leaves that rise above the plant and then grow around it. This latter monocot strategy has the advantage of protecting the growing tip at the base of the plant for much of its life. It enables grasses to survive extensive grazing, and it is the growth strategy that is used by plants like wheat, maize and rice. Despite its use by plants of ecological and agricultural importance, this monocot strategy is not well understood. In this project, a collaborative team of US (University of California, Berkeley) and UK (John Innes Centre) investigators will use a combination of tools including high resolution imaging and computational methods to test mechanisms that will develop predictive and testable models. These models will describe the processes of growth and shape changes in the monocot leaf. Because the position of the leaf blade has an effect on the amount of light a plant can harvest for photosynthesis, this work could significantly impact crop yield. Biotech industries will benefit from the work, through greater fundamental understanding of processes involved in tissue development. The investigators will be actively engaged in education at all levels, including K-12 and public education, through the development of hands on training activities, YouTube videos, and more traditional methods of diffusion of research findings. Computational modeling has led to preliminary hypotheses of monocot leaf development. A key idea is that growth is oriented by a polarity field, which is analogous to the way a magnetic field can be used to orient directions of navigation. The observed growth and shape changes of the monocot leaf can then be explained by simple changes in the polarity field and the pattern of growth rates it orients. The aim of this project is to test and further build upon this model and determine whether the polarity fields and the growth rates the model predicts are correct using the maize monocot system (which has the advantage of well-developed genetics and associated technologies.) By looking at markers that highlight the presumed polarity fields and by determining the growth rates in different regions of the leaf, predictions of the model can be tested. Models will also be tested by analyzing mutants in which key transitions of development are disrupted. These studies will be made quantitative by writing computer programs that automatically extract the relevant measures. New computational methods will also be developed and applied to this system so that the processes can be understood at different levels, i.e. from cellular to tissue scale.This collaborative US/UK project is supported by the US National Science Foundation and the UK Biotechnology and Biological Sciences Research Council.