Han Xiaozhen, Tohge Takayuki, Lalor Pierce, Dockery Peter, Devaney Nicholas, Esteves-Ferreira Alberto A, Fernie Alisdair R, Sulpice Ronan
Plant Systems Biology Research Lab, Plant and AgriBiosciences, School of Natural Sciences, NUI GalwayGalway, Ireland.
Max Planck Institute of Molecular Plant PhysiologyPotsdam-Golm, Germany.
Front Plant Sci. 2017 Aug 9;8:1394. doi: 10.3389/fpls.2017.01394. eCollection 2017.
Primary metabolism is closely linked to plant productivity and quality. Thus, a better understanding of the regulation of primary metabolism by photoreceptors has profound implications for agricultural practices and management. This study aims at identifying the role of light signaling in the regulation of primary metabolism, with an emphasis on starch. We first screened seven cryptochromes and phytochromes mutants for starch phenotype. The mutant showed impairment in starch accumulation while its biomass, chlorophyll fluorescence parameters, and leaf anatomy were unaffected, this deficiency being present over the whole vegetative growth period. Mutation of plastidial nucleoside diphosphate kinase-2 (NDPK2), acting downstream of phytochromes, also caused a deficit in starch accumulation. Besides, the was down-regulated in . Those results suggest that PHYAB affect starch accumulation through NDPK2 and APS1. Then, we determined changes in starch and primary metabolites in single , single , double grown in light conditions differing in light intensity and/or light spectral content. PHYA is involved in starch accumulation in all the examined light conditions, whereas PHYB only exhibits a role under low light intensity (44 ± 1 μmol m s) or low R:FR (11.8 ± 0.6). PCA analysis of the metabolic profiles in the mutants and wild type (WT) suggested that PHYB acts as a major regulator of the leaf metabolic status in response to light intensity. Overall, we propose that PHYA and PHYB signaling play essential roles in the control of primary metabolism in leaves in response to light.
初生代谢与植物生产力和品质密切相关。因此，深入了解光受体对初生代谢的调控对农业实践和管理具有深远意义。本研究旨在确定光信号在初生代谢调控中的作用，重点关注淀粉。我们首先筛选了7个隐花色素和光敏色素突变体的淀粉表型。该突变体在淀粉积累方面存在缺陷，而其生物量、叶绿素荧光参数和叶片解剖结构未受影响，这种缺陷在整个营养生长阶段都存在。质体核苷二磷酸激酶-2（NDPK2）的突变，其作用于光敏色素下游，也导致淀粉积累不足。此外，该基因在[具体名称]中表达下调。这些结果表明，PHYAB通过NDPK2和APS1影响淀粉积累。然后，我们测定了在光强和/或光谱含量不同的光照条件下生长的单突变体、单突变体、双突变体中淀粉和初生代谢物的变化。在所有检测的光照条件下，PHYA都参与淀粉积累，而PHYB仅在低光强（44±1 μmol m-2 s-1）或低红光：远红光（11.8±0.6）条件下发挥作用。对突变体和野生型（WT）代谢谱的主成分分析表明，PHYB作为叶片代谢状态对光强响应的主要调节因子。总体而言，我们认为PHYA和PHYB信号在响应光照时对[植物名称]叶片初生代谢的控制中起重要作用。
