title: Efficient high light acclimation involves rapid processes at multiple mechanistic levels.
abstract: Like no other chemical or physical parameter, the natural light environment of plants changes with high speed and jumps of enormous intensity. To cope with this variability, photosynthetic organisms have evolved sensing and response mechanisms that allow efficient acclimation. Most signals originate from the chloroplast itself. In addition to very fast photochemical regulation, intensive molecular communication is realized within the photosynthesizing cell, optimizing the acclimation process. Current research has opened up new perspectives on plausible but mostly unexpected complexity in signalling events, crosstalk, and process adjustments. Within seconds and minutes, redox states, levels of reactive oxygen species, metabolites, and hormones change and transmit information to the cytosol, modifying metabolic activity, gene expression, translation activity, and alternative splicing events. Signalling pathways on an intermediate time scale of several minutes to a few hours pave the way for long-term acclimation. Thereby, a new steady state of the transcriptome, proteome, and metabolism is realized within rather short time periods irrespective of the previous acclimation history to shade or sun conditions. This review provides a time line of events during six hours in the 'stressful' life of a plant.
authors.affiliation: Biochemistry and Physiology of Plants, Faculty of Biology, W5-134, Bielefeld University, University Street 25, 33501 Bielefeld, Germany karl-josef.dietz@uni-bielefeld.de.
authors.forename: Karl-Josef
authors.initials: KJ
authors.lastname: Dietz
mesh_terms: D000064:Acclimatization; D002467:Cell Nucleus / Q000378:metabolism; D002736:Chloroplasts / Q000378:metabolism / Q000502:physiology*; D018506:Gene Expression Regulation, Plant; D008027:Light; D008954:Models, Biological; D010084:Oxidation-Reduction; D055668:Photochemical Processes; D010788:Photosynthesis; D010937:Plant Growth Regulators / Q000378:metabolism; D014176:Protein Biosynthesis; D017382:Reactive Oxygen Species / Q000378:metabolism; D015398:Signal Transduction; D013269:Stochastic Processes
chemical_list: D010937:Plant Growth Regulators; D017382:Reactive Oxygen Species
keywords: Cell signalling; gene expression; light acclimation; metabolites; photosynthesis; redox regulation; translation.