Dose-dependent effects of 1O2 in chloroplasts are determined by its timing and localization of production. (29th September 2018)

• Record Type: Journal Article
• Authors: Wang, Liangsheng; Apel, Klaus
• Is Part Of: Journal of experimental botany. Volume 70:Number 1(2019)
• Page Start: 29
• Page End: 40
• Publication Date: 2018-09-29
• Subjects: Chloroplast -- photosynthesis -- reactive oxygen species -- signaling -- singlet oxygen -- stress; Botany -- Periodicals; Botany, Experimental -- Periodicals; Plant physiology -- Periodicals; 580
• DOI: 10.1093/jxb/ery343
• Languages: English
• ISSNs: 0022-0957

Abstract

Abstract : In plants, 1 O2 is primarily generated in chloroplasts and can act as a signal. Its effects are not only dose dependent, but also rely on localization and timing of its production. Abstract: In plants, highly reactive singlet oxygen ( 1 O2 ) is known to inhibit photosynthesis and to damage the cell as a cytotoxin. However, more recent studies have also proposed 1 O2 as a signal. In plants under stress, not only 1 O2 but also other reactive oxygen species (ROS) are generated simultaneously, thus making it difficult to link a particular response to the release of 1 O2 and establish a signaling role for this ROS. This obstacle has been overcome by the identification of conditional mutants of Arabidopsis thaliana that selectively generate 1 O2 and trigger various 1 O2 -mediated responses. In chloroplasts of these mutants, chlorophyll or its biosynthetic intermediates may act as a photosensitizer and generate 1 O2 . These 1 O2 -mediated responses are not only dependent on the dosage of 1 O2 but also are determined by the timing and suborganellar localization of its production. This spatial- and temporal-dependent variability of 1 O2 -mediated responses emphasizes the importance of 1 O2 as a highly versatile and short-lived signal that acts throughout the life cycle of a plant.