Loading content, please wait..
| Authors | Guidi, L; Brunetti, C; Fini, A; Agati, G; Ferrini, F; Gori, A; Tattini, M |
| Author Full Name | Guidi, Lucia; Brunetti, Cecilia; Fini, Alessio; Agati, Giovanni; Ferrini, Francesco; Gori, Antonella; Tattini, Massimiliano |
| Title | UV radiation promotes flavonoid biosynthesis, while negatively affecting the biosynthesis and the de-epoxidation of xanthophylls: Consequence for photoprotection? |
| Source | ENVIRONMENTAL AND EXPERIMENTAL BOTANY |
| Language | English |
| Document Type | Article |
| Author Keywords | Carotenoids; Chloroplast flavonoids; Excess visible light; Nonphotochemical quenching; Oleaceae; Quercetin; Zeaxanthin |
| Keywords Plus | ULTRAVIOLET-B RADIATION; HIGH SOLAR-RADIATION; ROOT-ZONE SALINITY; LIGUSTRUM-VULGARE; CHLOROPHYLL FLUORESCENCE; VIOLAXANTHIN DEEPOXIDATION; PHOTOSYNTHETIC PIGMENT; ANTIOXIDANT DEFENSE; ENERGY-DISSIPATION; FUNCTIONAL ROLES |
| Abstract | There is evidence that UV radiation may detrimentally affect the biosynthesis of carotenoids, particularly de-epoxided xanthophylls, while strongly promoting phenylpropanoid, particularly flavonoid biosynthesis in a range of taxa. Here we tested the hypothesis that mesophyll flavonoids might protect chloroplasts from UV-induced photo-oxidative damage, by partially compensating for the UV-induced depression of xanthophyll biosynthesis. To test this hypothesis we grew two members of the Oleaceae family, Ligustrum vulgare L. and Phillyrea latifolia L, under either partial shading or fully exposed to sunlight, in the presence or in the absence of UV radiation. The examined species, which display very similar flavonoid composition, largely differ in their ability to limit the transmission of UV and visible light through the leaf and, hence, in the accumulation of flavonoids in mesophyll cells. We conducted measurements of photosynthesis, chlorophyll a fluorescence kinetics, the concentrations of individual carotenoids and phenylpropanoids at the level of whole-leaf, as well as the content of epidermal flavonoids. We also performed multispectral fluorescence micro-imaging to unveil the intra-cellular distribution of flavonoids in mesophyll cells. UV radiation decreased the concentration of carotenoids, particularly of xanthophylls, while greatly promoting the accumulation of flavonoids in palisade parenchyma cells. These effects were much greater in L. vulgare than in P. latifolia. UV radiation significantly inhibited the de-epoxidation of xanthophyll cycle pigments, while enhancing the concentration of luteolin, and particularly of quercetin glycosides. Flavonoids accumulated in the vacuole and the chloroplasts in palisade cells proximal to the adaxial epidermis. We hypothesize that flavonoids might complement the photo-protective functions of xanthophylls in the chloroplasts of mesophyll cells exposed to the greatest doses of UV radiation. However, UV radiation might result in adaxial mesophyll cells being less effective in dissipating the excess of radiant energy, e.g., by decreasing their capacity of thermal dissipation of excess visible light in the chloroplast. (C) 2016 Elsevier B.V. All rights reserved. |
| Author Address | [Guidi, Lucia] Univ Pisa, Dept Agr Food & Environm, I-56124 Pisa, Italy; [Brunetti, Cecilia] Natl Res Council Italy CNR, Trees & Timber Inst, I-50019 Florence, Italy; [Brunetti, Cecilia; Fini, Alessio; Ferrini, Francesco; Gori, Antonella] Univ Florence, Dept Agri Food Prod & Environm Sci, I-50019 Florence, Italy; [Agati, Giovanni] Natl Res Council Italy CNR, Inst Appl Phys Nello Carrara, I-50019 Florence, Italy; [Tattini, Massimiliano] Natl Res Council Italy CNR, Inst Sustainable Plant Protect, I-50019 Florence, Italy |
| Reprint Address | Tattini, M (corresponding author), Natl Res Council Italy CNR, Inst Sustainable Plant Protect, I-50019 Florence, Italy. |
| E-mail Address | massimiliano.tattini@ipsp.cnr.it |
| ResearcherID Number | Cecilia, Brunetti/Q-4724-2018; Tattini, Massimiliano/K-1238-2019; GORI, ANTONELLA/Q-5222-2018 |
| ORCID Number | Cecilia, Brunetti/0000-0002-8531-6076; Tattini, Massimiliano/0000-0001-5434-8860; AGATI, GIOVANNI/0000-0003-0855-9389; GUIDI, LUCIA/0000-0002-2472-720X; GORI, ANTONELLA/0000-0002-7304-7526; FINI, ALESSIO/0000-0002-9713-689X |
| Funding Agency and Grant Number | PRIN Project TreeCity (MIUR, Rome, Italy)Ministry of Education, Universities and Research (MIUR) |
| Funding Text | Work in the authors' laboratory was funded partly by the PRIN Project TreeCity (MIUR, Rome, Italy). |
| Times Cited | 19 |
| Total Times Cited Count (WoS, BCI, and CSCD) | 20 |
| Publisher | PERGAMON-ELSEVIER SCIENCE LTD |
| Publisher City | OXFORD |
| Publisher Address | THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND |
| ISSN | 0098-8472 |
| 29-Character Source Abbreviation | ENVIRON EXP BOT |
| ISO Source Abbreviation | Environ. Exp. Bot. |
| Publication Date | JUL |
| Year Published | 2016 |
| Volume | 127 |
| Beginning Page | 14 |
| Ending Page | 25 |
| Digital Object Identifier (DOI) | 10.1016/j.envexpbot.2016.03.002 |
| Page Count | 12 |
| Web of Science Category | Plant Sciences; Environmental Sciences |
| Subject Category | Plant Sciences; Environmental Sciences & Ecology |
| Document Delivery Number | DL3EJ |
| Unique Article Identifier | WOS:000375516700002 |
| Plants associated with this reference |