Ascorbate-mediated regulation of growth, photoprotection, and photoinhibition in Arabidopsis thaliana
| Autor: | Alexandra J. Townsend, Nurhayati Razak, Barbara Karpinska, Sarah Alomrani, Brwa Rasool, Alexander V. Ruban, Christine H. Foyer, William Plumb |
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| Rok vydání: | 2018 |
| Předmět: |
Anthocyanin
0106 biological sciences 0301 basic medicine NPQ Photoinhibition oxidation Physiology Arabidopsis Ascorbic Acid Plant Science Xanthophylls Photosynthesis 01 natural sciences Anthocyanins 03 medical and health sciences chemistry.chemical_compound Etiolation Arabidopsis thaliana ro-GFP chemistry.chemical_classification photosynthesis photoinhibition biology Wild type food and beverages biology.organism_classification Research Papers Plant Leaves Zeaxanthin antioxidants zeaxanthin 030104 developmental biology Biochemistry chemistry Chlorophyll Xanthophyll Photoprotection 010606 plant biology & botany |
| Zdroj: | Journal of Experimental Botany |
| ISSN: | 1460-2431 0022-0957 |
| DOI: | 10.1093/jxb/ery170 |
| Popis: | Analysis of synthesis mutants demonstrates an ascorbate requirement for growth under low light and for high light-dependent anthocyanin accumulation, but no consistent effects on photoinhibition or zeaxanthin accumulation were found. The requirements for ascorbate for growth and photosynthesis were assessed under low (LL; 250 µmol m–2 s–1) or high (HL; 1600 µmol m–2 s–1) irradiance in wild-type Arabidopsis thaliana and two ascorbate synthesis mutants (vtc2-1 and vtc2-4) that have 30% wild-type ascorbate levels. The low ascorbate mutants had the same numbers of leaves but lower rosette area and biomass than the wild type under LL. Wild-type plants experiencing HL had higher leaf ascorbate, anthocyanin, and xanthophyll pigments than under LL. In contrast, leaf ascorbate levels were not increased under HL in the mutant lines. While the degree of oxidation measured using an in vivo redox reporter in the nuclei and cytosol of the leaf epidermal and stomatal cells was similar under both irradiances in all lines, anthocyanin levels were significantly lower in the low ascorbate mutants than in the wild type under HL. Differences in the photosynthetic responses of vtc2-1 and vtc2-4 mutants were observed. Unlike vtc2-1, the vtc2-4 mutants had wild-type zeaxanthin contents. While both low ascorbate mutants had lower levels of non-photochemical quenching of chlorophyll a fluorescence (NPQ) than the wild type under HL, qPd values were greater only in vtc2-1 leaves. Ascorbate is therefore essential for growth but not for photoprotection. |
| Databáze: | OpenAIRE |
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