Regulation of Stomatal Development in Arabidopsis

0237016SacksStomata含有调节通过嫩枝表皮进行气体交换的气孔。气孔形成的控制是叶片发育和植物生产力的核心。气孔是通过不对称分裂产生和形成图案的。太多嘴(TMM)是一种富含亮氨酸重复序列的受体样蛋白，它调节气孔的数量和分布。在叶片发育过程中，TMM在一组干细胞中表达。它似乎以一种细胞类型和器官特有的方式控制着细胞增殖和分化之间的平衡。TMM也可能接收到用于定向不对称分裂平面的空间线索，以便气孔不会彼此相邻地形成。因此，TMM可能在发育层次的多个水平上起作用。下游信号可能需要与其他蛋白质结合，因为TMM缺乏细胞质结构域。将对TMM蛋白质复合体进行生化分析，并对相互作用蛋白质的特性和功能进行表征。TMM与另一个功能重叠的基因之间的关系将在遗传学、表达、生化和发育水平上进行定义。TMM的表达模式将在叶片和地上部发育的背景下进行评估。将研究非对称分割，以确定TMM是否定向极化轴以及它如何控制分割平面。这项工作解决了植物发育中的基本问题，如受体如何调节不对称分裂的平面和频率，以及细胞位置和通讯如何有助于模式的形成。因为其他植物，包括农作物，都有类似TMM的基因，这项工作应该为更广泛地理解气孔发育和陆地植物的一个关键特征的进化提供一个背景。

0237016SacksStomata contain pores that regulate gas exchange through the shoot epidermis. The control of stomatal formation is central to leaf development and plant productivity. Stomata are produced and patterned via asymmetric divisions. TOO MANY MOUTHS (TMM) is a leucine-rich repeat receptor-like protein that regulates stomatal number and distribution. TMM is expressed in a population of stem cells during leaf development. It appears to control the balance between cell proliferation and differentiation in a cell-type- and organ-specific manner. TMM is also likely to receive spatial cues used to orient the plane of asymmetric division so that stomata do not form adjacent to each other. Thus TMM probably functions at multiple levels of a developmental hierarchy. Downstream signaling is likely to require association with other proteins because TMM lacks a cytoplasmic domain. The TMM protein complex will be analyzed biochemically, and the identity and function of interacting proteins will be characterized. The relationship between TMM and another gene with overlapping functions will be defined at the levels of genetics, expression, biochemistry, and development. The expression pattern of TMM will be evaluated in the context of leaf and shoot development. Asymmetric divisions will be studied to determine whether TMM orients an axis of polarity and how it controls the division plane. This work addresses fundamental questions in plant development such as how a receptor regulates the plane and frequency of asymmetric division, and how cell position and communication contribute to pattern formation. Because other plants, including crops, have TMM-like genes, this work should provide a context for a wider understanding stomatal development and of the evolution of a key feature of land plants.