Journal article
Photosynthesis in Arabidopsis Is Unaffected by the Function of the Vacuolar K + Channel TPK3
Plant physiology (Bethesda), Vol.180(3), pp.1322-1335
07/2019
Handle:
https://hdl.handle.net/2376/110590
PMCID: PMC6752931
PMID: 31053658
Abstract
Photosynthesis is limited by the slow relaxation of nonphotochemical quenching, which primarily dissipates excess absorbed light energy as heat. Because the heat dissipation process is proportional to light-driven thylakoid lumen acidification, manipulating thylakoid ion and proton flux via transport proteins could improve photosynthesis. However, an important aspect of the current understanding of the thylakoid ion transportome is inaccurate. Using fluorescent protein fusions, we show that the Arabidopsis (
) two-pore K
channel TPK3, which had been reported to mediate thylakoid K
flux, localizes to the tonoplast, not the thylakoid. The localization of TPK3 outside of the thylakoids is further supported by the absence of TPK3 in isolated thylakoids as well as the inability of isolated chloroplasts to import TPK3 protein. In line with the subcellular localization of TPK3 in the vacuole, we observed that photosynthesis in the Arabidopsis null mutant
, which carries a transfer DNA insertion in the first exon, remains unaffected. To gain a comprehensive understanding of how thylakoid ion flux impacts photosynthetic efficiency under dynamic growth light regimes, we performed long-term photosynthesis imaging of established and newly isolated transthylakoid K
- and Cl
-flux mutants. Our results underpin the importance of the thylakoid ion transport proteins potassium cation efflux antiporter KEA3 and voltage-dependent chloride channel VCCN1 and suggest that the activity of yet unknown K
channel(s), but not TPK3, is critical for optimal photosynthesis in dynamic light environments.
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Details
- Title
- Photosynthesis in Arabidopsis Is Unaffected by the Function of the Vacuolar K + Channel TPK3
- Creators
- Ricarda Höhner - Plant Physiology, School of Biological Sciences, Washington State University, Pullman, Washington 99164-4236Viviana Correa Galvis - Max Planck Institute of Molecular Plant Physiology, Wissenschaftspark Golm, 14476 Potsdam, GermanyDeserah D Strand - Max Planck Institute of Molecular Plant Physiology, Wissenschaftspark Golm, 14476 Potsdam, GermanyCarsten Völkner - Plant Physiology, School of Biological Sciences, Washington State University, Pullman, Washington 99164-4236Moritz Krämer - Plant Physiology, School of Biological Sciences, Washington State University, Pullman, Washington 99164-4236Michaela Messer - Max Planck Institute of Molecular Plant Physiology, Wissenschaftspark Golm, 14476 Potsdam, GermanyFirdevs Dinc - Max Planck Institute of Molecular Plant Physiology, Wissenschaftspark Golm, 14476 Potsdam, GermanyInga Sjuts - Ludwig Maximilian University Munich, Department I, Plant Biochemistry, 82152 Planegg-Martinsried, GermanyBettina Bölter - Ludwig Maximilian University Munich, Department I, Plant Biochemistry, 82152 Planegg-Martinsried, GermanyDavid M Kramer - Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, Michigan 48824Ute Armbruster - Max Planck Institute of Molecular Plant Physiology, Wissenschaftspark Golm, 14476 Potsdam, GermanyHans-Henning Kunz - Plant Physiology, School of Biological Sciences, Washington State University, Pullman, Washington 99164-4236 henning.kunz@wsu.edu
- Publication Details
- Plant physiology (Bethesda), Vol.180(3), pp.1322-1335
- Academic Unit
- Biological Sciences, School of
- Publisher
- United States
- Identifiers
- 99900547239201842
- Language
- English
- Resource Type
- Journal article