Redox regulation of PGRL1 at the onset of low light intensity. (28th April 2020)

• Record Type: Journal Article
• Authors: Wolf, Bat‐Chen; Isaacson, Tal; Tiwari, Vivekanand; Dangoor, Inbal; Mufkadi, Sapir; Danon, Avihai
• Is Part Of: Plant journal. Volume 103:Number 2(2020)
• Page Start: 715
• Page End: 725
• Publication Date: 2020-04-28
• Subjects: acclimating response -- Arabidopsis thaliana -- homeostatic‐like control -- non‐photochemical quenching -- oxidative regulation -- regulatory disulfide; Plant molecular biology -- Periodicals; Plant cells and tissues -- Periodicals; Botany -- Periodicals; 580
• DOI: 10.1111/tpj.14764
• Languages: English
• ISSNs: 0960-7412

Abstract

SUMMARY: PGR5‐LIKE PHOTOSYNTHETIC PHENOTYPE1 (PGRL1) regulates photosystem I cyclic electron flow which transiently activates non‐photochemical quenching at the onset of light. Here, we show that a disulfide‐based mechanism of PGRL1 regulated this process in vivo at the onset of low light levels. We found that PGRL1 regulation depended on active formation of key regulatory disulfides in the dark, and that PGR5 was required for this activity. The disulfide state of PGRL1 was modulated in plants by counteracting reductive and oxidative components and reached a balanced state that depended on the light level. We propose that the redox regulation of PGRL1 fine‐tunes a timely activation of photosynthesis at the onset of low light. Significance Statement: Redox regulation of PGRL1 displays special characteristics that fit its role in the regulation of cyclic electron flow at the onset of low light, i.e. initially fast reductive activation followed by slow reoxidation until a dynamic balance is reached. We propose that the redox regulation of PGRL1 fine‐tunes a timely activation of photosynthesis at the onset of low light.