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Chlororespiration Controls Growth Under Intermittent Light.
- Source :
-
Plant physiology [Plant Physiol] 2019 Feb; Vol. 179 (2), pp. 630-639. Date of Electronic Publication: 2018 Nov 29. - Publication Year :
- 2019
-
Abstract
- Whereas photosynthetic function under steady-state light conditions has been well characterized, little is known about its changes that occur in response to light fluctuations. Chlororespiration, a simplified respiratory chain, is widespread across all photosynthetic lineages, but its role remains elusive. Here, we show that chlororespiration plays a crucial role in intermittent-light conditions in the green alga Chlamydomonas reinhardtii Chlororespiration, which is localized in thylakoid membranes together with the photosynthetic electron transfer chain, involves plastoquinone reduction and plastoquinol oxidation by a Plastid Terminal Oxidase (PTOX). We show that PTOX activity is critical for growth under intermittent light, with severe growth defects being observed in a mutant lacking PTOX2, the major plastoquinol oxidase. We demonstrate that the hampered growth results from a major change in the kinetics of redox relaxation of the photosynthetic electron transfer chain during the dark periods. This change, in turn, has a dramatic effect on the physiology of photosynthesis during the light periods, notably stimulating cyclic electron flow at the expense of the linear electron flow.<br /> (© 2019 American Society of Plant Biologists. All Rights Reserved.)
- Subjects :
- Chlamydomonas reinhardtii genetics
Cytochrome b6f Complex metabolism
Darkness
Electron Transport
Light
Mutation
Oxidation-Reduction
Oxidoreductases genetics
Photosynthesis physiology
Photosystem I Protein Complex metabolism
Plant Proteins genetics
Plastoquinone analogs & derivatives
Plastoquinone metabolism
Thylakoids metabolism
Up-Regulation
Chlamydomonas reinhardtii growth & development
Chlamydomonas reinhardtii metabolism
Oxidoreductases metabolism
Plant Proteins metabolism
Subjects
Details
- Language :
- English
- ISSN :
- 1532-2548
- Volume :
- 179
- Issue :
- 2
- Database :
- MEDLINE
- Journal :
- Plant physiology
- Publication Type :
- Academic Journal
- Accession number :
- 30498023
- Full Text :
- https://doi.org/10.1104/pp.18.01213