Efficient high light acclimation involves rapid processes at multiple mechanistic levels.
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.
['Dietz|Karl-Josef|KJ|']
D000064:Acclimatization D002467:Cell Nucleus D002736:Chloroplasts D018506:Gene Expression Regulation, Plant D008027:Light D008954:Models, Biological D010084:Oxidation-Reduction D055668:Photochemical Processes D010788:Photosynthesis D010937:Plant Growth Regulators D014176:Protein Biosynthesis D017382:Reactive Oxygen Species D015398:Signal Transduction D013269:Stochastic Processes
light acclimation metabolites gene expression Cell signalling photosynthesis redox regulation translation.