Chloroplasts are key players to cope with light and temperature stress

• Published in: Trends in plant science Vol. 27; no. 6; pp. 577 - 587
• Main Authors: Schwenkert, Serena, Fernie, Alisdair R., Geigenberger, Peter, Leister, Dario, Möhlmann, Torsten, Naranjo, Belen, Neuhaus, H. Ekkehard
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.06.2022; Elsevier BV
• Subjects: abiotic stress; Acclimation; Acclimatization; Chloroplasts; Climate change; Environmental conditions; Light intensity; Luminous intensity; metabolism; Modulators; Organelles; Plant breeding; Plant stress; stress tolerance; Stroma; temperature; chloroplasts; stress tolerance; metabolism; acclimation; abiotic stress
• ISSN: 1360-1385; 1878-4372; 1878-4372
• DOI: 10.1016/j.tplants.2021.12.004

Under natural environmental conditions, changes in light intensity and temperature are closely interwoven, and of all organelles, only chloroplasts react strongly upon alterations of these two parameters. We review increasing evidence indicating that changes in chloroplast metabolism are critical for the comprehensive cellular answer in a challenging environment. This cellular answer starts with rapid modifications of thylakoid-located processes, followed by modifications in the stroma and transport activities across the chloroplast envelope. We propose that the ‘modulators’ involved contribute to plant stress tolerance and that deciphering of their characteristics is essential to understand ‘acclimation’. Especially in times of climatic changes, we must gain knowledge on physiological reactions that might become instrumental for directed breeding strategies aiming to develop stress-tolerant crop plants. Reactions in chloroplasts initiate the cellular acclimation response to rapid changes in light intensities and environmental temperature.Thylakoid, stromal, and envelope-associated processes are sequentially initiated and set the chloroplast in the center of further cellular responses, allowing a new homeostatic level to be reached.Proteins hidden thus far, and novel modes as well as regulatory properties of selected reactions, have been identified and act as modulators of plant stress tolerance. Corresponding analyses complete our understanding of essential plant characteristics and potentially pave the way for directed breeding towards more stress tolerant crop plants.