Zeidler Mathias
Institute of Plant Physiology, Justus-Liebig-University Giessen, Giessen, Germany.
Methods Mol Biol. 2022;2494:37-45. doi: 10.1007/978-1-0716-2297-1_4.
Plants utilize light as sole energy source. To maximize light capture, they are able to detect the light direction and orient themselves toward the light source. This phototropic response is mediated by the plant blue-light photoreceptors phototropin1 and phototropin2 (phot1 and phot2). Although fully differentiated plants also exhibit this response, it can be best observed in etiolated seedlings. Differences in light between the illuminated and shaded site of a seedling stem lead to changes in the auxin distribution, resulting in cell elongation on the shaded site. Since phototropism connects light perception, signaling, and auxin transport, it is of great interest to analyze this response with a fast and simple method. Moreover, pre-exposure to red light enhances the phototropic response via phytochrome A (phyA) and phyB action. Here we describe a method to analyze the phototropic response of Arabidopsis seedlings to blue light and the enhanced response with a red-light pretreatment. With numerous mutants available, its fast germination, and its small size, Arabidopsis is well suited for this analysis. Different genotypes can be simultaneously probed in less than a week.
植物利用光作为唯一的能量来源。为了最大限度地捕获光能，它们能够检测光的方向并朝着光源定向生长。这种向光性反应是由植物蓝光光感受器向光素1和向光素2（phot1和phot2）介导的。虽然完全分化的植物也表现出这种反应，但在黄化幼苗中最容易观察到。幼苗茎的受光部位和遮光部位之间的光照差异导致生长素分布发生变化，从而使遮光部位的细胞伸长。由于向光性涉及光感知、信号传导和生长素运输，因此用一种快速简单的方法来分析这种反应非常有意义。此外，红光预照射通过光敏色素A（phyA）和光敏色素B（phyB）的作用增强向光性反应。在这里，我们描述了一种分析拟南芥幼苗对蓝光的向光性反应以及红光预处理增强反应的方法。由于有大量可用的突变体、发芽快且植株体积小，拟南芥非常适合进行这种分析。不同基因型可以在不到一周的时间内同时进行检测。
