Nozue Kazunari, Tat An V, Kumar Devisetty Upendra, Robinson Matthew, Mumbach Maxwell R, Ichihashi Yasunori, Lekkala Saradadevi, Maloof Julin N
Department of Plant Biology, University of California, Davis, Davis, California, United States of America.
PLoS Genet. 2015 Apr 15;11(4):e1004953. doi: 10.1371/journal.pgen.1004953. eCollection 2015 Apr.
Shade from neighboring plants limits light for photosynthesis; as a consequence, plants have a variety of strategies to avoid canopy shade and compete with their neighbors for light. Collectively the response to foliar shade is called the shade avoidance syndrome (SAS). The SAS includes elongation of a variety of organs, acceleration of flowering time, and additional physiological responses, which are seen throughout the plant life cycle. However, current mechanistic knowledge is mainly limited to shade-induced elongation of seedlings. Here we use phenotypic profiling of seedling, leaf, and flowering time traits to untangle complex SAS networks. We used over-representation analysis (ORA) of shade-responsive genes, combined with previous annotation, to logically select 59 known and candidate novel mutants for phenotyping. Our analysis reveals shared and separate pathways for each shade avoidance response. In particular, auxin pathway components were required for shade avoidance responses in hypocotyl, petiole, and flowering time, whereas jasmonic acid pathway components were only required for petiole and flowering time responses. Our phenotypic profiling allowed discovery of seventeen novel shade avoidance mutants. Our results demonstrate that logical selection of mutants increased success of phenotypic profiling to dissect complex traits and discover novel components.
邻近植物的遮荫会限制光合作用所需的光照；因此，植物有多种策略来避免冠层遮荫并与邻居争夺光照。对叶片遮荫的整体反应被称为避荫综合征（SAS）。SAS包括多种器官的伸长、开花时间的加速以及其他生理反应，这些反应在植物的整个生命周期中都能看到。然而，目前的机制知识主要局限于遮荫诱导的幼苗伸长。在这里，我们使用幼苗、叶片和开花时间性状的表型分析来梳理复杂的SAS网络。我们对遮荫响应基因进行了超几何富集分析（ORA），并结合先前的注释，从逻辑上选择了59个已知的和候选的新突变体进行表型分析。我们的分析揭示了每种避荫反应的共同和独立途径。特别是，生长素途径成分是下胚轴、叶柄和开花时间避荫反应所必需的，而茉莉酸途径成分仅为叶柄和开花时间反应所必需。我们的表型分析发现了17个新的避荫突变体。我们的结果表明，从逻辑上选择突变体增加了表型分析剖析复杂性状和发现新成分的成功率。
