Linking Epidermis and Mesophyll Signalling. Anatomy and Impact in Photosynthesis.

本项目旨在探索表皮发育的信号通路及其与叶肉发育的关系，并阐明其对光合作用表现的影响。我们将结合植物信号和生理学，将这两个学科与分子生物学和功能基因组学方法结合起来。叶片表面的气孔和多孔的叶肉是植物进行有效的光合作用和蒸腾作用气体交换的先决条件。气孔或叶肉促进气体交换的速率称为电导。气孔导度(GS)取决于气孔的大小和密度，气孔的排列和其他结构因素，包括细胞壁厚度和质膜和叶绿体膜的组成，决定了叶肉导度(Gm)。我们认为，气孔发育和叶肉结构的协调可能通过在叶片水平上优化潜在的GS和GM的信号通路来实现。有了这一点，就有可能通过控制结构之间的关系以及这两种组织的电导率来提高水的利用效率。尽管在过去的几年里，叶的表皮发育、图案和内部解剖已经被很好地研究了，但它们几乎没有被放在一起研究。在这个意义上，A.thaliana突变体stomgen和CDK8是解决这一假说的理想选择。在这些突变体中，气孔的发育被诱导或抑制，例如，二氧化碳交换和光合作用可能受到影响。

The current project aims to explore the signalling pathways of epidermal development and their connection with mesophyll development and elucidate the impact on photosynthetic performance. We will combine plant signalling and physiology, integrating both disciplines with molecular biology and functional genomics methodologies. Stomatal pores on the leaf surface and a porous leaf mesophyll are prerequisites for effective plant gas exchange for photosynthesis and transpiration. The rate at which the stomata or mesophyll facilitate gas exchange is called conductance. The stomatal conductance (gs) depends on the size and density of the stomata, and the arrangement of the air spaces and other structural factors, including cell wall thickness and composition of the plasma and chloroplast membranes, determines the mesophyll conductance (gm). We believe that the coordination of the development of the stomata and the mesophyll structure is possible through signalling pathways to optimize potential gs and gm at the leaf level. With this, there is potential to improve water use efficiency by manipulating the relationship between the structures and, therefore, the conductance of these two tissues. Although the epidermal development, patterning, and inner anatomy of the leave have been well studied in the past years, they have barely been studied together. In this sense, the A. thaliana mutants stomagen and cdk8 are ideal for addressing this hypothesis. In these mutants, the stomata development is induced or repressed; for instance, CO2 exchange and photosynthesis may be affected.