Signal integration in stomatal development

气孔是陆地植物的关键进化适应，也是一个直观的模型系统，用于分析植物发育是如何从细胞增殖、命运承诺以及细胞大小、位置和形状的控制进行的。生命需要嫩芽和大气之间的气体交换。二氧化碳进入会在光合作用中产生新的碳水化合物，而H2O蒸发会使植物和地球降温。这些气体通过气孔移动，气孔是由两个围绕着毛孔的保卫细胞组成的表皮瓣膜，气孔的打开和关闭允许二氧化碳内流，并最大限度地减少水分损失。 尽管它们在全球气体水平和农业中起着关键作用，但气孔的形成仍处于发现阶段。特定病灶：(I)年轻保卫细胞之间的串扰可能产生瓣膜的镜状对称。只有MUS基因才能塑造这种对称性，而整个基因途径可能参与其中，细胞活动如何协调塑造仍不清楚。(Ii)我们发现气孔模式受主控植物激素生长素局部水平的调控，但尚未确定所有主要生长素信号通路参与的程度。(Iii)四唇(FLP)MYB蛋白确保气孔只含有两个细胞，但许多FLP靶基因的整合作用如何限制生长和控制生长素途径还有待确定。主要目标：(1)确定胡须受体信号如何协调细胞生物学和瓣膜成形，并确定该途径的其他成员。(2)利用荧光报告基因(DII)、化学抑制剂和与生长素受体和转录因子途径相关的突变体来探测生长素对气孔发育的控制。(3)分析FLP如何整合关键基因的表达来协调细胞的增殖和模式，阻止由于DNA过度和异常增殖而导致的气孔扩大，并通过生长素信号来协调这些事件。

Stomata, which are a key evolutionary adaptation of land plants, are also a visually accessible model system for analyzing how plant development progresses from cell proliferation, fate commitment, and the control of cell size, position, and shape. Life requires gas exchange between shoots and the atmosphere. CO2 entry yields new carbohydrates in photosynthesis, and H2O evaporation cools the plant and the planet. These gases move through stomata, epidermal valves made up of two guard cells around a pore whose opening and closing allows CO2 influx and minimizes water loss. Despite their key role in global gas levels and agriculture, how stomata form is still in its discovery phase. Specific foci: (i) Cross-talk between young guard cells likely generates the mirror-like symmetry of the valve. Only the MUS gene is known shape this symmetry, whereas an entire gene pathway is likely involved, and how cellular events coordinate shaping is still obscure. (ii) We found stomatal patterning to be regulated by local levels of the master plant hormone auxin, but have yet to determine the extent to which all major auxin signaling pathways are involved. (iii) The FOUR LIPS (FLP) MYB protein ensures that stomata contain just two cells, but how the integrated action of many FLP target genes restrict proliferation and control auxin pathways needs to be determined. Key goals: (1) Define how receptor signaling by MUSTACHES coordinates cell biology with valve shaping, and identify additional members of the pathway. (2) Probe auxin control of stomatal development using fluorescence reporters (DII), chemical inhibitors, and mutants related to the auxin receptor and transcription factor pathways. (3) Analyze how FLP integrates the expression of key genes to orchestrate cell proliferation and patterning, blocks stomatal enlargement resulting from excess and abnormal DNA multiplication, and coordinates these events via auxin signaling.