On the significance of mechanosensing for seed development and maturation

机械传感描述了物理力量作为发展事件触发器的过程。例如，轻微的触摸或风可以引起形态变化。另一个例子与芸苔科植物的胚胎发生有关：当种子内正在膨胀的胚胎与胚囊壁接触时，它开始弯曲和折叠。我们之前的研究结果表明，机械约束对种子发育有额外的影响，即作为胚胎从生长转向成熟的信号，用种子储存产物（储存油和蛋白质）的积累取代器官扩张。本项目将测试机械传感在油菜（Brassica napus）胚胎对物理约束的结构、代谢和分子反应调控中的意义。在空间限制和非限制条件下生长的发育胚胎将通过(1)无创磁共振成像（用于连续三维监测胚胎生长和油脂沉积），(2)傅立叶变换红外显微镜（用于检测激素、糖和其他代谢中间体的组织梯度），(3)代谢物谱分析（LC/MS）和(4)转录物谱分析（RNASeq）进行分析。最终，本项目旨在确定种子机械传感的功能意义。探索生长的物理限制、代谢开关和种子/胚胎成熟之间的机制联系将引起广大科学受众的高度兴趣，并可能为作物种子改良开辟新的途径。

Mechanosensing describes the process whereby physical forces act as the trigger for a developmental event. For example, a subtle touch or wind can induce morphological changes. Another example relates to embryogenesis of Brassicaceae: when the expanding embryo within a seed makes contact with the embryosac wall, it starts to bend and fold. Own previous findings let us suggest that mechanical constraints have additional effects on seed development, namely as signal to the embryo to switch from growth into maturation, replacing organ expansion with the accumulation of seed storage products (storage oils and proteins). This project will test the significance of mechanosensing for the regulation of the structural, metabolic and molecular responses to physical restraint in embryos of oilseed rape (Brassica napus). Developing embryos, growing under spatially restricted and non-restricted conditions, will be analysed by (1) non-invasive magnetic resonance imaging (for continuous three-dimensional monitoring of embryo growth and oil deposition), (2) Fourier-Transform-Infrared-microscopy (for detecting tissue gradients in hormones, sugars and other metabolic intermediates), (3) metabolite profiling (LC/MS) and (4) transcript profiling (RNASeq). Ultimately, this project aims to define the functional significance of mechanosensing for seeds. The exploration of a mechanistic link between a physical constraint to growth, metabolic switches and seed/embryo maturation would be of high interest to a wide scientific audience, and could open new avenues for crop seed improvement.