Molecular Plant Biology, Department of Biochemistry, University of Turku, , 20014 Turku, Finland.
Philos Trans R Soc Lond B Biol Sci. 2014 Mar 3;369(1640):20130229. doi: 10.1098/rstb.2013.0229. Print 2014 Apr 19.
The amount of light energy that is harvested and directed to the photosynthetic machinery is regulated in order to control the production of reactive oxygen species (ROS) in leaf tissues. ROS have important roles as signalling factors that instigate and mediate a range of cellular responses, suggesting that the mechanisms regulating light-harvesting and photosynthetic energy transduction also affect cell signalling. In this study, we exposed wild-type (WT) Arabidopsis and mutants impaired in the regulation of photosynthetic light-harvesting (stn7, tap38 and npq4) to transient high light (HL) stress in order to study the role of these mechanisms for up- and downregulation of gene expression under HL stress. The mutants, all of which have disturbed regulation of excitation energy transfer and distribution, responded to transient HL treatment with surprising similarity to the WT in terms of general 'abiotic stress-regulated' genes associated with hydrogen peroxide and 12-oxo-phytodienoic acid signalling. However, we identified distinct expression profiles in each genotype with respect to induction of singlet oxygen and jasmonic acid-dependent responses. The results of this study suggest that the control of excitation energy transfer interacts with hormonal regulation. Furthermore, the photosynthetic pigment-protein complexes appear to operate as receptors that sense the energetic balance between the photosynthetic light reactions and downstream metabolism.
为了控制叶片组织中活性氧(ROS)的产生,被收获并引导至光合作用机器的光能被调节。ROS 作为信号因子具有重要作用,可引发和介导多种细胞反应,这表明调节光能捕获和光合作用能量转导的机制也会影响细胞信号转导。在这项研究中,我们使野生型(WT)拟南芥和光合作用光捕获调节受损的突变体(stn7、tap38 和 npq4)暴露于短暂的高光(HL)胁迫下,以研究这些机制在 HL 胁迫下对基因表达的上调和下调的作用。这些突变体的激发能传递和分布调节都受到干扰,它们对短暂的 HL 处理的反应与 WT 非常相似,与与过氧化氢和 12-氧-植物二烯酸信号有关的一般“非生物胁迫调节”基因有关。然而,我们在每种基因型中都发现了与单线态氧诱导和茉莉酸依赖反应相关的不同表达谱。这项研究的结果表明,激发能传递的控制与激素调节相互作用。此外,光合色素-蛋白复合物似乎作为受体发挥作用,感知光合作用光反应和下游代谢之间的能量平衡。