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Busch A, Gerbracht JV, Davies K, Hoecker U, Hess S. Comparative transcriptomics elucidates the cellular responses of an aeroterrestrial zygnematophyte to UV radiation. JOURNAL OF EXPERIMENTAL BOTANY 2024; 75:3624-3642. [PMID: 38520340 PMCID: PMC11156808 DOI: 10.1093/jxb/erae131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Accepted: 03/22/2024] [Indexed: 03/25/2024]
Abstract
The zygnematophytes are the closest relatives of land plants and comprise several lineages that adapted to a life on land. Species of the genus Serritaenia form colorful, mucilaginous capsules, which surround the cells and block harmful solar radiation, one of the major terrestrial stressors. In eukaryotic algae, this 'sunscreen mucilage' represents a unique photoprotective strategy, whose induction and chemical background are unknown. We generated a de novo transcriptome of Serritaenia testaceovaginata and studied its gene regulation under moderate UV radiation (UVR) that triggers sunscreen mucilage under experimental conditions. UVR induced the repair of DNA and the photosynthetic apparatus as well as the synthesis of aromatic specialized metabolites. Specifically, we observed pronounced expressional changes in the production of aromatic amino acids, phenylpropanoid biosynthesis genes, potential cross-membrane transporters of phenolics, and extracellular, oxidative enzymes. Interestingly, the most up-regulated enzyme was a secreted class III peroxidase, whose embryophyte homologs are involved in apoplastic lignin formation. Overall, our findings reveal a conserved, plant-like UVR perception system (UVR8 and downstream factors) in zygnematophyte algae and point to a polyphenolic origin of the sunscreen pigment of Serritaenia, whose synthesis might be extracellular and oxidative, resembling that of plant lignins.
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Affiliation(s)
- Anna Busch
- Department of Biology, University of Cologne, Zülpicher Str. 47b, D-50674 Cologne, Germany
| | - Jennifer V Gerbracht
- Department of Biology, University of Cologne, Zülpicher Str. 47b, D-50674 Cologne, Germany
| | - Kevin Davies
- The New Zealand Institute for Plant and Food Research Limited, Private Bag 11600, Palmerston North 4442, New Zealand
| | - Ute Hoecker
- Institute for Plant Sciences and Cluster of Excellence on Plant Sciences (CEPLAS), Biocenter, University of Cologne, Zülpicher Strasse 47b, D-50674, Cologne, Germany
| | - Sebastian Hess
- Department of Biology, University of Cologne, Zülpicher Str. 47b, D-50674 Cologne, Germany
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2
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Ač A, Jansen MAK, Grace J, Urban O. Unravelling the neglected role of ultraviolet radiation on stomata: A meta-analysis with implications for modelling ecosystem-climate interactions. PLANT, CELL & ENVIRONMENT 2024; 47:1769-1781. [PMID: 38314642 DOI: 10.1111/pce.14841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Revised: 01/17/2024] [Accepted: 01/23/2024] [Indexed: 02/06/2024]
Abstract
Stomata play a pivotal role in regulating gas exchange between plants and the atmosphere controlling water and carbon cycles. Accordingly, we investigated the impact of ultraviolet-B radiation, a neglected environmental factor varying with ongoing global change, on stomatal morphology and function by a Comprehensive Meta-Analysis. The overall UV effect at the leaf level is to decrease stomatal conductance, stomatal aperture and stomatal size, although stomatal density was increased. The significant decline in stomatal conductance is marked (6% in trees and >10% in grasses and herbs) in short-term experiments, with more modest decreases noted in long-term UV studies. Short-term experiments in growth chambers are not representative of long-term field UV effects on stomatal conductance. Important consequences of altered stomatal function are hypothesized. In the short term, UV-mediated stomatal closure may reduce carbon uptake but also water loss through transpiration, thereby alleviating deleterious effects of drought. However, in the long term, complex changes in stomatal aperture, size, and density may reduce the carbon sequestration capacity of plants and increase vegetation and land surface temperatures, potentially exacerbating negative effects of drought and/or heatwaves. Therefore, the expected future strength of carbon sink capacity in high-UV regions is likely overestimated.
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Affiliation(s)
- Alexander Ač
- Global Change Research of the Czech Academy of Sciences, Brno, Czech Republic
| | - Marcel A K Jansen
- Global Change Research of the Czech Academy of Sciences, Brno, Czech Republic
- School of Biological, Earth and Environmental Sciences, Environmental Research Institute, UCC, Cork, Ireland
| | - John Grace
- Global Change Research of the Czech Academy of Sciences, Brno, Czech Republic
- School of GeoSciences, University of Edinburgh, Edinburgh, UK
| | - Otmar Urban
- Global Change Research of the Czech Academy of Sciences, Brno, Czech Republic
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3
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Chen S, Podolec R, Arongaus AB, Fuchs C, Loubéry S, Demarsy E, Ulm R. Functional divergence of Arabidopsis REPRESSOR OF UV-B PHOTOMORPHOGENESIS 1 and 2 in repression of flowering. PLANT PHYSIOLOGY 2024; 194:1563-1576. [PMID: 37956407 PMCID: PMC10904346 DOI: 10.1093/plphys/kiad606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 09/27/2023] [Accepted: 10/19/2023] [Indexed: 11/15/2023]
Abstract
Photoperiodic plants coordinate the timing of flowering with seasonal light cues, thereby optimizing their sexual reproductive success. The WD40-repeat protein REPRESSOR OF UV-B PHOTOMORPHOGENESIS 2 (RUP2) functions as a potent repressor of UV RESISTANCE LOCUS 8 (UVR8) photoreceptor-mediated UV-B induction of flowering under noninductive, short-day conditions in Arabidopsis (Arabidopsis thaliana); however, in contrast, the closely related RUP1 seems to play no major role. Here, analysis of chimeric ProRUP1:RUP2 and ProRUP2:RUP1 expression lines suggested that the distinct functions of RUP1 and RUP2 in repressing flowering are due to differences in both their coding and regulatory DNA sequences. Artificial altered expression using tissue-specific promoters indicated that RUP2 functions in repressing flowering when expressed in mesophyll and phloem companion cells, whereas RUP1 functions only when expressed in phloem companion cells. Endogenous RUP1 expression in vascular tissue was quantified as lower than that of RUP2, likely underlying the functional difference between RUP1 and RUP2 in repressing flowering. Taken together, our findings highlight the importance of phloem vasculature expression of RUP2 in repressing flowering under short days and identify a basis for the functional divergence of Arabidopsis RUP1 and RUP2 in regulating flowering time.
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Affiliation(s)
- Song Chen
- Department of Plant Sciences, Section of Biology, Faculty of Sciences, University of Geneva, Geneva 1211, Switzerland
| | - Roman Podolec
- Department of Plant Sciences, Section of Biology, Faculty of Sciences, University of Geneva, Geneva 1211, Switzerland
- Institute of Genetics and Genomics of Geneva (iGE3), University of Geneva, Geneva 1211, Switzerland
| | - Adriana B Arongaus
- Department of Plant Sciences, Section of Biology, Faculty of Sciences, University of Geneva, Geneva 1211, Switzerland
| | - Christelle Fuchs
- Department of Plant Sciences, Section of Biology, Faculty of Sciences, University of Geneva, Geneva 1211, Switzerland
| | - Sylvain Loubéry
- Department of Plant Sciences, Section of Biology, Faculty of Sciences, University of Geneva, Geneva 1211, Switzerland
| | - Emilie Demarsy
- Department of Plant Sciences, Section of Biology, Faculty of Sciences, University of Geneva, Geneva 1211, Switzerland
| | - Roman Ulm
- Department of Plant Sciences, Section of Biology, Faculty of Sciences, University of Geneva, Geneva 1211, Switzerland
- Institute of Genetics and Genomics of Geneva (iGE3), University of Geneva, Geneva 1211, Switzerland
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4
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Liu W, Giuriani G, Havlikova A, Li D, Lamont DJ, Neugart S, Velanis CN, Petersen J, Hoecker U, Christie JM, Jenkins GI. Phosphorylation of Arabidopsis UVR8 photoreceptor modulates protein interactions and responses to UV-B radiation. Nat Commun 2024; 15:1221. [PMID: 38336824 PMCID: PMC10858049 DOI: 10.1038/s41467-024-45575-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Accepted: 01/27/2024] [Indexed: 02/12/2024] Open
Abstract
Exposure of plants to ultraviolet-B (UV-B) radiation initiates transcriptional responses that modify metabolism, physiology and development to enhance viability in sunlight. Many of these regulatory responses to UV-B radiation are mediated by the photoreceptor UV RESISTANCE LOCUS 8 (UVR8). Following photoreception, UVR8 interacts directly with multiple proteins to regulate gene expression, but the mechanisms that control differential protein binding to initiate distinct responses are unknown. Here we show that UVR8 is phosphorylated at several sites and that UV-B stimulates phosphorylation at Serine 402. Site-directed mutagenesis to mimic Serine 402 phosphorylation promotes binding of UVR8 to REPRESSOR OF UV-B PHOTOMORPHOGENESIS (RUP) proteins, which negatively regulate UVR8 action. Complementation of the uvr8 mutant with phosphonull or phosphomimetic variants suggests that phosphorylation of Serine 402 modifies UVR8 activity and promotes flavonoid biosynthesis, a key UV-B-stimulated response that enhances plant protection and crop nutritional quality. This research provides a basis to understand how UVR8 interacts differentially with effector proteins to regulate plant responses to UV-B radiation.
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Affiliation(s)
- Wei Liu
- School of Molecular Biosciences, College of Medical, Veterinary and Life Sciences, Bower Building, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Giovanni Giuriani
- School of Molecular Biosciences, College of Medical, Veterinary and Life Sciences, Bower Building, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Anezka Havlikova
- School of Molecular Biosciences, College of Medical, Veterinary and Life Sciences, Bower Building, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Dezhi Li
- School of Molecular Biosciences, College of Medical, Veterinary and Life Sciences, Bower Building, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Douglas J Lamont
- FingerPrints Proteomics Facility, School of Life Sciences, Discovery Centre, University of Dundee, Dow Street, Dundee, DD1 5EH, UK
| | - Susanne Neugart
- Department of Crop Sciences, Division Quality and Sensory of Plant Products, Georg-August-Universität Göttingen, D-37075, Göttingen, Germany
| | - Christos N Velanis
- School of Molecular Biosciences, College of Medical, Veterinary and Life Sciences, Bower Building, University of Glasgow, Glasgow, G12 8QQ, UK
- School of Life, Health and Chemical Sciences, Faculty of Science, Technology, Engineering and Maths, Venables Building, The Open University, Walton Hall Campus, Milton Keynes, MK7 6AA, UK
| | - Jan Petersen
- School of Molecular Biosciences, College of Medical, Veterinary and Life Sciences, Bower Building, University of Glasgow, Glasgow, G12 8QQ, UK
- Matthias Schleiden Institute of Genetics, Bioinformatics and Molecular Botany, Friedrich Schiller University, 07743, Jena, Germany
| | - Ute Hoecker
- Botanical Institute and Cluster of Excellence on Plant Sciences (CEPLAS), Biocenter, University of Köln, 50923, Köln, Germany
| | - John M Christie
- School of Molecular Biosciences, College of Medical, Veterinary and Life Sciences, Bower Building, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Gareth I Jenkins
- School of Molecular Biosciences, College of Medical, Veterinary and Life Sciences, Bower Building, University of Glasgow, Glasgow, G12 8QQ, UK.
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5
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Sharma A, Pridgeon AJ, Liu W, Segers F, Sharma B, Jenkins GI, Franklin KA. ELONGATED HYPOCOTYL5 (HY5) and HY5 HOMOLOGUE (HYH) maintain shade avoidance suppression in UV-B. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2023; 115:1394-1407. [PMID: 37243898 PMCID: PMC10953383 DOI: 10.1111/tpj.16328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Revised: 05/17/2023] [Accepted: 05/23/2023] [Indexed: 05/29/2023]
Abstract
Reductions in red to far-red ratio (R:FR) provide plants with an unambiguous signal of vegetational shade and are monitored by phytochrome photoreceptors. Plants integrate this information with other environmental cues to determine the proximity and density of encroaching vegetation. Shade-sensitive species respond to reductions in R:FR by initiating a suite of developmental adaptations termed shade avoidance. These include the elongation of stems to facilitate light foraging. Hypocotyl elongation is driven by increased auxin biosynthesis promoted by PHYTOCHROME INTERACTING FACTORs (PIF) 4, 5 and 7. UV-B perceived by the UV RESISTANCE LOCUS 8 (UVR8) photoreceptor rapidly inhibits shade avoidance, in part by suppressing PIF4/5 transcript accumulation and destabilising PIF4/5 protein. Here, we show that longer-term inhibition of shade avoidance is sustained by ELONGATED HYPOCOTYL 5 (HY5) and HY5 HOMOLOGUE (HYH), which regulate transcriptional reprogramming of genes involved in hormone signalling and cell wall modification. HY5 and HYH are elevated in UV-B and suppress the expression of XYLOGLUCAN ENDOTRANSGLUCOSYLASE/HYDROLASE (XTH) genes involved in cell wall loosening. They additionally increase expression GA2-OXIDASE1 (GA2ox1) and GA2ox2, encoding gibberellin catabolism enzymes that act redundantly to stabilise the PIF-inhibiting DELLA proteins. UVR8 therefore regulates temporally distinct signalling pathways to first rapidly inhibit and subsequently maintain suppression of shade avoidance following UV-B exposure.
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Affiliation(s)
- Ashutosh Sharma
- School of Biological Sciences, Life Sciences BuildingUniversity of BristolBristolBS8 1TQUK
| | - Ashley J. Pridgeon
- School of Biological Sciences, Life Sciences BuildingUniversity of BristolBristolBS8 1TQUK
| | - Wei Liu
- School of Molecular Biosciences, College of Medical, Veterinary and Life SciencesUniversity of GlasgowGlasgowG12 8QQUK
| | - Francisca Segers
- School of Biological Sciences, Life Sciences BuildingUniversity of BristolBristolBS8 1TQUK
| | - Bhavana Sharma
- School of Biological Sciences, Life Sciences BuildingUniversity of BristolBristolBS8 1TQUK
| | - Gareth I. Jenkins
- School of Molecular Biosciences, College of Medical, Veterinary and Life SciencesUniversity of GlasgowGlasgowG12 8QQUK
| | - Keara A. Franklin
- School of Biological Sciences, Life Sciences BuildingUniversity of BristolBristolBS8 1TQUK
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6
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Zhao J, Bo K, Pan Y, Li Y, Yu D, Li C, Chang J, Wu S, Wang Z, Zhang X, Gu X, Weng Y. Phytochrome-interacting factor PIF3 integrates phytochrome B and UV-B signaling pathways to regulate gibberellin- and auxin-dependent growth in cucumber hypocotyls. JOURNAL OF EXPERIMENTAL BOTANY 2023; 74:4520-4539. [PMID: 37201922 DOI: 10.1093/jxb/erad181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Accepted: 05/11/2023] [Indexed: 05/20/2023]
Abstract
In Arabidopsis, the photoreceptors phytochrome B (PhyB) and UV-B resistance 8 (UVR8) mediate light responses that play a major role in regulating photomorphogenic hypocotyl growth, but how they crosstalk to coordinate this process is not well understood. Here we report map-based cloning and functional characterization of an ultraviolet (UV)-B-insensitive, long-hypocotyl mutant, lh1, and a wild-type-like mutant, lh2, in cucumber (Cucumis sativus), which show defective CsPhyB and GA oxidase2 (CsGA20ox-2), a key gibberellic acid (GA) biosynthesis enzyme, respectively. The lh2 mutation was epistatic to lh1 and partly suppressed the long-hypocotyl phenotype in the lh1lh2 double mutant. We identified phytochrome interacting factor (PIF) CsPIF3 as playing a critical role in integrating the red/far-red and UV-B light responses for hypocotyl growth. We show that two modules, CsPhyB-CsPIF3-CsGA20ox-2-DELLA and CsPIF3-auxin response factor 18 (CsARF18), mediate CsPhyB-regulated hypocotyl elongation through GA and auxin pathways, respectively, in which CsPIF3 binds to the G/E-box motifs in the promoters of CsGA20ox-2 and CsARF18 to regulate their expression. We also identified a new physical interaction between CsPIF3 and CsUVR8 mediating CsPhyB-dependent, UV-B-induced hypocotyl growth inhibition. Our work suggests that hypocotyl growth in cucumber involves a complex interplay of multiple photoreceptor- and phytohormone-mediated signaling pathways that show both conservation with and divergence from those in Arabidopsis.
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Affiliation(s)
- Jianyu Zhao
- Horticulture Department, University of Wisconsin, Madison WI 53706, USA
| | - Kailiang Bo
- Horticulture Department, University of Wisconsin, Madison WI 53706, USA
- State Key Laboratory of Vegetable Biobreeding, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Yupeng Pan
- Horticulture Department, University of Wisconsin, Madison WI 53706, USA
- College of Horticulture, Northwest A& F University, Yangling 712100, China
| | - Yuhong Li
- College of Horticulture, Northwest A& F University, Yangling 712100, China
| | - Daoliang Yu
- State Key Laboratory of Vegetable Biobreeding, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Chuang Li
- State Key Laboratory of Vegetable Biobreeding, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Jiang Chang
- College of Horticulture, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Shuang Wu
- College of Horticulture, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Zhongyi Wang
- State Key Laboratory of Vegetable Biobreeding, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Xiaolan Zhang
- State Key Laboratory of Vegetable Biobreeding, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Xingfang Gu
- State Key Laboratory of Vegetable Biobreeding, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Yiqun Weng
- Horticulture Department, University of Wisconsin, Madison WI 53706, USA
- USDA-ARS Vegetable Crops Research Unit, Madison, WI 53705, USA
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7
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Dikiy I, Swingle D, Toy K, Edupuganti UR, Rivera-Cancel G, Gardner KH. Diversity of function and higher-order structure within HWE sensor histidine kinases. J Biol Chem 2023; 299:104934. [PMID: 37331599 PMCID: PMC10359499 DOI: 10.1016/j.jbc.2023.104934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2023] [Revised: 06/09/2023] [Accepted: 06/12/2023] [Indexed: 06/20/2023] Open
Abstract
Integral to the protein structure/function paradigm, oligomeric state is typically conserved along with function across evolution. However, notable exceptions such as the hemoglobins show how evolution can alter oligomerization to enable new regulatory mechanisms. Here, we examine this linkage in histidine kinases (HKs), a large class of widely distributed prokaryotic environmental sensors. While the majority of HKs are transmembrane homodimers, members of the HWE/HisKA2 family can deviate from this architecture as exemplified by our finding of a monomeric soluble HWE/HisKA2 HK (EL346, a photosensing light-oxygen-voltage [LOV]-HK). To further explore the diversity of oligomerization states and regulation within this family, we biophysically and biochemically characterized multiple EL346 homologs and found a range of HK oligomeric states and functions. Three LOV-HK homologs are primarily dimeric with differing structural and functional responses to light, while two Per-ARNT-Sim-HKs interconvert between differentially active monomers and dimers, suggesting dimerization might control enzymatic activity for these proteins. Finally, we examined putative interfaces in a dimeric LOV-HK, finding that multiple regions contribute to dimerization. Our findings suggest the potential for novel regulatory modes and oligomeric states beyond those traditionally defined for this important family of environmental sensors.
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Affiliation(s)
- Igor Dikiy
- Structural Biology Initiative, CUNY Advanced Science Research Center, New York, New York, USA
| | - Danielle Swingle
- Structural Biology Initiative, CUNY Advanced Science Research Center, New York, New York, USA; PhD. Program in Biochemistry, The Graduate Center - City University of New York, New York, New York, USA
| | - Kaitlyn Toy
- Structural Biology Initiative, CUNY Advanced Science Research Center, New York, New York, USA; Department of Chemistry and Biochemistry, City College of New York, New York, New York, USA
| | - Uthama R Edupuganti
- Structural Biology Initiative, CUNY Advanced Science Research Center, New York, New York, USA; PhD. Program in Biochemistry, The Graduate Center - City University of New York, New York, New York, USA
| | - Giomar Rivera-Cancel
- Department of Internal Medicine, UT Southwestern Medical Center, Dallas, Texas, USA
| | - Kevin H Gardner
- Structural Biology Initiative, CUNY Advanced Science Research Center, New York, New York, USA; Department of Chemistry and Biochemistry, City College of New York, New York, New York, USA; PhD. Programs in Biochemistry, Biology, and Chemistry, The Graduate Center - City University of New York, New York, New York, USA.
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8
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Santin M, Simoni S, Vangelisti A, Giordani T, Cavallini A, Mannucci A, Ranieri A, Castagna A. Transcriptomic Analysis on the Peel of UV-B-Exposed Peach Fruit Reveals an Upregulation of Phenolic- and UVR8-Related Pathways. PLANTS (BASEL, SWITZERLAND) 2023; 12:plants12091818. [PMID: 37176875 PMCID: PMC10180693 DOI: 10.3390/plants12091818] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 04/18/2023] [Accepted: 04/27/2023] [Indexed: 05/15/2023]
Abstract
UV-B treatment deeply influences plant physiology and biochemistry, especially by activating the expression of responsive genes involved in UV-B acclimation through a UV-B-specific perception mechanism. Although the UV-B-related molecular responses have been widely studied in Arabidopsis, relatively few research reports deepen the knowledge on the influence of post-harvest UV-B treatment on fruit. In this work, a transcriptomic approach is adopted to investigate the transcriptional modifications occurring in the peel of UV-B-treated peach (Prunus persica L., cv Fairtime) fruit after harvest. Our analysis reveals a higher gene regulation after 1 h from the irradiation (88% of the differentially expressed genes-DEGs), compared to 3 h recovery. The overexpression of genes encoding phenylalanine ammonia-lyase (PAL), chalcone syntase (CHS), chalcone isomerase (CHI), and flavonol synthase (FLS) revealed a strong activation of the phenylpropanoid pathway, resulting in the later increase in the concentration of specific flavonoid classes, e.g., anthocyanins, flavones, dihydroflavonols, and flavanones, 36 h after the treatment. Upregulation of UVR8-related genes (HY5, COP1, and RUP) suggests that UV-B-triggered activation of the UVR8 pathway occurs also in post-harvest peach fruit. In addition, a regulation of genes involved in the cell-wall dismantling process (PME) is observed. In conclusion, post-harvest UV-B exposure deeply affects the transcriptome of the peach peel, promoting the activation of genes implicated in the biosynthesis of phenolics, likely via UVR8. Thus, our results might pave the way to a possible use of post-harvest UV-B treatments to enhance the content of health-promoting compounds in peach fruits and extending the knowledge of the UVR8 gene network.
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Affiliation(s)
- Marco Santin
- Department of Agriculture, Food and Environment, University of Pisa, Via del Borghetto 80, 56124 Pisa, Italy
| | - Samuel Simoni
- Department of Agriculture, Food and Environment, University of Pisa, Via del Borghetto 80, 56124 Pisa, Italy
| | - Alberto Vangelisti
- Department of Agriculture, Food and Environment, University of Pisa, Via del Borghetto 80, 56124 Pisa, Italy
| | - Tommaso Giordani
- Department of Agriculture, Food and Environment, University of Pisa, Via del Borghetto 80, 56124 Pisa, Italy
- Interdepartmental Research Center Nutrafood ''Nutraceuticals and Food for Health'', University of Pisa, Via del Borghetto 80, 56124 Pisa, Italy
| | - Andrea Cavallini
- Department of Agriculture, Food and Environment, University of Pisa, Via del Borghetto 80, 56124 Pisa, Italy
- Interdepartmental Research Center Nutrafood ''Nutraceuticals and Food for Health'', University of Pisa, Via del Borghetto 80, 56124 Pisa, Italy
| | - Alessia Mannucci
- Department of Agriculture, Food and Environment, University of Pisa, Via del Borghetto 80, 56124 Pisa, Italy
| | - Annamaria Ranieri
- Department of Agriculture, Food and Environment, University of Pisa, Via del Borghetto 80, 56124 Pisa, Italy
- Interdepartmental Research Center Nutrafood ''Nutraceuticals and Food for Health'', University of Pisa, Via del Borghetto 80, 56124 Pisa, Italy
| | - Antonella Castagna
- Department of Agriculture, Food and Environment, University of Pisa, Via del Borghetto 80, 56124 Pisa, Italy
- Interdepartmental Research Center Nutrafood ''Nutraceuticals and Food for Health'', University of Pisa, Via del Borghetto 80, 56124 Pisa, Italy
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9
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Zhang Q, Lin L, Fang F, Cui B, Zhu C, Luo S, Yin R. Dissecting the functions of COP1 in the UVR8 pathway with a COP1 variant in Arabidopsis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2023; 113:478-492. [PMID: 36495441 DOI: 10.1111/tpj.16059] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Revised: 11/21/2022] [Accepted: 12/02/2022] [Indexed: 06/17/2023]
Abstract
COP1 is a critical repressor of plant photomorphogenesis in darkness. However, COP1 plays distinct roles in the photoreceptor UVR8 pathway in Arabidopsis thaliana. COP1 interacts with ultraviolet B (UV-B)-activated UVR8 monomers and promotes their retention and accumulation in the nucleus. Moreover, COP1 has a function in UV-B signaling, which involves the binding of its WD40 domain to UVR8 and HY5 via conserved Val-Pro (VP) motifs of these proteins. UV-B-activated UVR8 interacts with COP1 via both the core domain and the VP motif, leading to the displacement of HY5 from COP1 and HY5 stabilization. However, it remains unclear whether the function of COP1 in UV-B signaling is solely dependent on its VP motif binding capacity and whether UV-B regulates the subcellular localization of COP1. Based on published structures of the COP1 WD40 domain, we generated a COP1 variant with a single amino acid substitution, COP1C509S , which cannot bind to VP motifs but retains the ability to interact with the UVR8 core domain. UV-B only marginally increased nuclear YFP-COP1 levels and significantly promoted YFP-COP1 accumulation in the cytosol, but did not exert the same effects on YFP-COP1C509S . Thus, the full UVR8-COP1 interaction is important for COP1 accumulation in the cytosol. Notably, UV-B signaling including activation of HY5 transcription was obviously inhibited in the Arabidopsis lines expressing YFP-COP1C509S , which cannot bind VP motifs. We conclude that the full binding of UVR8 to COP1 leads to the predominant accumulation of COP1 in the cytosol and that COP1 has an additional function in UV-B signaling besides VP binding-mediated protein destabilization.
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Affiliation(s)
- Qianwen Zhang
- School of Agriculture and Biology, Shanghai Jiao Tong University, 800 Dongchuan RD. Minhang District, Shanghai, 200240, China
| | - Li Lin
- School of Agriculture and Biology, Shanghai Jiao Tong University, 800 Dongchuan RD. Minhang District, Shanghai, 200240, China
- Key Laboratory of Urban Agriculture Ministry of Agriculture, Shanghai Jiao Tong University, 200240, Shanghai, China
- Joint Center for Single Cell Biology, Shanghai Jiao Tong University, 200240, Shanghai, China
| | - Fang Fang
- School of Agriculture and Biology, Shanghai Jiao Tong University, 800 Dongchuan RD. Minhang District, Shanghai, 200240, China
| | - Beimi Cui
- Institute of Molecular Plant Sciences, School of Biological Sciences, University of Edinburgh, Edinburgh, EH9 3BF, UK
| | - Cheng Zhu
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Shukun Luo
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Ruohe Yin
- School of Agriculture and Biology, Shanghai Jiao Tong University, 800 Dongchuan RD. Minhang District, Shanghai, 200240, China
- Key Laboratory of Urban Agriculture Ministry of Agriculture, Shanghai Jiao Tong University, 200240, Shanghai, China
- Joint Center for Single Cell Biology, Shanghai Jiao Tong University, 200240, Shanghai, China
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10
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Liao X, Jenkins GI. Cysteines have a role in conformation of the UVR8 photoreceptor. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2022; 111:583-594. [PMID: 35608127 PMCID: PMC9546227 DOI: 10.1111/tpj.15841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Revised: 05/17/2022] [Accepted: 05/19/2022] [Indexed: 06/15/2023]
Abstract
The UV RESISTANCE LOCUS 8 (UVR8) photoreceptor mediates plant responses to Ultraviolet-B (UV-B) wavelengths. The UVR8 dimer dissociates into monomers following UV-B photoreception, a process accompanied by conformational changes that facilitate interaction of UVR8 with proteins that initiate responses. However, the importance of particular amino acids in maintaining UVR8 conformation and modulating protein interactions is poorly understood. Here we examine the roles of cysteine amino acids C231 and C335 in UVR8 structure and function. UVR8C231S,C335S mutant protein forms dimers and monomerizes similarly to wild-type UVR8. UVR8C231S,C335S interacts with CONSTITUTIVELY PHOTOMORPHOGENIC 1 (COP1) in plants to initiate photomorphogenic responses to UV-B, although the interaction is weaker when examined in yeast two-hybrid assays. Similarly, the interaction of UVR8C231S,C335S with REPRESSOR OF UV-B PHOTOMORPHOGENESIS (RUP) proteins is weaker in both plants and yeast compared with wild-type UVR8. Re-dimerization of UVR8 in plants, which is mediated by RUP proteins, occurs with reduced efficiency in UVR8C231S,C335S . Fluorescence resonance energy transfer analysis indicates that UVR8C231S,C335S has an altered conformation in plants, in that the N- and C-termini appear closer together, which may explain the altered protein interactions.
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Affiliation(s)
- Xinyang Liao
- Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, Bower BuildingUniversity of GlasgowGlasgowG12 8QQUK
| | - Gareth I. Jenkins
- Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, Bower BuildingUniversity of GlasgowGlasgowG12 8QQUK
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11
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Yoon HI, Kim J, Oh MM, Son JE. Prediction of Phenolic Contents Based on Ultraviolet-B Radiation in Three-Dimensional Structure of Kale Leaves. FRONTIERS IN PLANT SCIENCE 2022; 13:918170. [PMID: 35755700 PMCID: PMC9228028 DOI: 10.3389/fpls.2022.918170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Accepted: 05/20/2022] [Indexed: 06/15/2023]
Abstract
Ultraviolet-B (UV-B, 280-315 nm) radiation has been known as an elicitor to enhance bioactive compound contents in plants. However, unpredictable yield is an obstacle to the application of UV-B radiation to controlled environments such as plant factories. A typical three-dimensional (3D) plant structure causes uneven UV-B exposure with leaf position and age-dependent sensitivity to UV-B radiation. The purpose of this study was to develop a model for predicting phenolic accumulation in kale (Brassica oleracea L. var. acephala) according to UV-B radiation interception and growth stage. The plants grown under a plant factory module were exposed to UV-B radiation from UV-B light-emitting diodes with a peak at 310 nm for 6 or 12 h at 23, 30, and 38 days after transplanting. The spatial distribution of UV-B radiation interception in the plants was quantified using ray-tracing simulation with a 3D-scanned plant model. Total phenolic content (TPC), total flavonoid content (TFC), total anthocyanin content (TAC), UV-B absorbing pigment content (UAPC), and the antioxidant capacity were significantly higher in UV-B-exposed leaves. Daily UV-B energy absorbed by leaves and developmental age was used to develop stepwise multiple linear regression models for the TPC, TFC, TAC, and UAPC at each growth stage. The newly developed models accurately predicted the TPC, TFC, TAC, and UAPC in individual leaves with R 2 > 0.78 and normalized root mean squared errors of approximately 30% in test data, across the three growth stages. The UV-B energy yields for TPC, TFC, and TAC were the highest in the intermediate leaves, while those for UAPC were the highest in young leaves at the last stage. To the best of our knowledge, this study proposed the first statistical models for estimating UV-B-induced phenolic contents in plant structure. These results provided the fundamental data and models required for the optimization process. This approach can save the experimental time and cost required to optimize the control of UV-B radiation.
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Affiliation(s)
- Hyo In Yoon
- Department of Agriculture, Forestry and Bioresources, Seoul National University, Seoul, South Korea
| | - Jaewoo Kim
- Department of Agriculture, Forestry and Bioresources, Seoul National University, Seoul, South Korea
| | - Myung-Min Oh
- Division of Animal, Horticultural and Food Sciences, Chungbuk National University, Cheongju, South Korea
| | - Jung Eek Son
- Department of Agriculture, Forestry and Bioresources, Seoul National University, Seoul, South Korea
- Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul, South Korea
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12
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Zhang Z, Xu C, Zhang S, Shi C, Cheng H, Liu H, Zhong B. Origin and adaptive evolution of UV RESISTANCE LOCUS 8-mediated signaling during plant terrestrialization. PLANT PHYSIOLOGY 2022; 188:332-346. [PMID: 34662425 PMCID: PMC8774840 DOI: 10.1093/plphys/kiab486] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Accepted: 09/23/2021] [Indexed: 06/13/2023]
Abstract
UV RESISTANCE LOCUS 8 (UVR8) mediates photomorphogenic responses and acclimation to UV-B radiation by regulating the transcription of a series of transcription factors (TFs). However, the origin and evolution of UVR8-mediated signaling pathways remain largely unknown. In this study, we investigated the origin and evolution of the major components of the UVR8-mediated signaling pathway (UVR8, REPRESSOR OF UV-B PHOTOMORPHOGENESIS [RUP], BRI1-EMS-SUPPRESSOR1 [BES1], BES1-INTERACTING MYC-LIKE 1 (BIM1), WRKY DNA-BINDING PROTEIN 36 (WRKY36), MYB DOMAIN PROTEIN 73/77/13 [MYB73/MYB77/MYB13], and PHYTOCHROME INTERACTING FACTOR 4/5 [PIF4 and PIF5]) using comparative genomics and phylogenetic approaches. We showed that the central regulator UVR8 presented a conservative evolutionary route during plant evolution, and the evolutionary history of downstream negative regulators and TFs was different from that of green plant phylogeny. The canonical UVR8-CONSTITUTIVELY PHOTOMORPHOGENIC 1(COP1)/SUPPRESSOR OF PHYA-105 (SPA)-ELONGATED HYPOCOTYL 5 (HY5)-RUP signaling pathway originated in chlorophytes and conferred green algae the additional ability to cope with UV-B radiation. Moreover, the emergence of multiple UVR8-mediated signaling pathways in charophytes laid the foundations for the cross-talk between UV-B signals and endogenous hormone responses. Importantly, we observed signatures that reflect plant adaptations to high UV-B irradiance in subaerial/terrestrial environments, including positive selection in UVR8 and RUPs and increased copy number of some vital TFs. These results revealed that green plants not only experienced adaptive modifications in the canonical UVR8-COP1/SPA-HY5-RUP signaling pathway, but also diversified their UV-B signal transduction mechanisms through increasing cross-talk with other pathways, such as those associated with brassinosteroids and auxin. This study greatly expands our understanding of molecular evolution and adaptive mechanisms underlying plant UV-B acclimation.
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Affiliation(s)
- Zhenhua Zhang
- College of Life Sciences, Nanjing Normal University, Nanjing 210023, China
| | - Chenjie Xu
- College of Life Sciences, Nanjing Normal University, Nanjing 210023, China
| | - Shiyu Zhang
- College of Life Sciences, Nanjing Normal University, Nanjing 210023, China
| | - Chen Shi
- National Key Laboratory of Plant Molecular Genetics (NKLPMG), CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology (SIPPE), Chinese Academy of Sciences, Shanghai 200032, China
| | - Hong Cheng
- College of Life Sciences, Nanjing Normal University, Nanjing 210023, China
| | - Hongtao Liu
- National Key Laboratory of Plant Molecular Genetics (NKLPMG), CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology (SIPPE), Chinese Academy of Sciences, Shanghai 200032, China
| | - Bojian Zhong
- College of Life Sciences, Nanjing Normal University, Nanjing 210023, China
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13
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Dwijayanti A, Zhang C, Poh CL, Lautier T. Toward Multiplexed Optogenetic Circuits. Front Bioeng Biotechnol 2022; 9:804563. [PMID: 35071213 PMCID: PMC8766309 DOI: 10.3389/fbioe.2021.804563] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 12/06/2021] [Indexed: 11/25/2022] Open
Abstract
Owing to its ubiquity and easy availability in nature, light has been widely employed to control complex cellular behaviors. Light-sensitive proteins are the foundation to such diverse and multilevel adaptive regulations in a large range of organisms. Due to their remarkable properties and potential applications in engineered systems, exploration and engineering of natural light-sensitive proteins have significantly contributed to expand optogenetic toolboxes with tailor-made performances in synthetic genetic circuits. Progressively, more complex systems have been designed in which multiple photoreceptors, each sensing its dedicated wavelength, are combined to simultaneously coordinate cellular responses in a single cell. In this review, we highlight recent works and challenges on multiplexed optogenetic circuits in natural and engineered systems for a dynamic regulation breakthrough in biotechnological applications.
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Affiliation(s)
| | - Congqiang Zhang
- Singapore Institute of Food and Biotechnology Innovation (SIFBI), Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
| | - Chueh Loo Poh
- NUS Synthetic Biology for Clinical and Technological Innovation (SynCTI), Life Sciences Institute, National University of Singapore, Singapore, Singapore
| | - Thomas Lautier
- CNRS@CREATE, Singapore, Singapore
- Singapore Institute of Food and Biotechnology Innovation (SIFBI), Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
- TBI, Université de Toulouse, CNRS, INRAE, INSA, Toulouse, France
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14
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Meyer P, Van de Poel B, De Coninck B. UV-B light and its application potential to reduce disease and pest incidence in crops. HORTICULTURE RESEARCH 2021; 8:194. [PMID: 34465753 PMCID: PMC8408258 DOI: 10.1038/s41438-021-00629-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 07/08/2021] [Accepted: 07/13/2021] [Indexed: 05/03/2023]
Abstract
Ultraviolet-B radiation (280-315 nm), perceived by the plant photoreceptor UVR8, is a key environmental signal that influences plant growth and development and can reduce disease and pest incidence. The positive effect of UV-B on disease resistance and incidence in various plant species supports the implementation of supplemental UV-B radiation in sustainable crop production. However, despite many studies focusing on UV-B light, there is no consensus on the best mode of application. This review aims to analyze, evaluate, and organize the different application strategies of UV-B radiation in crop production with a focus on disease resistance. We summarize the physiological effects of UV-B light on plants and discuss how plants perceive and transduce UV-B light by the UVR8 photoreceptor as well as how this perception alters plant specialized metabolite production. Next, we bring together conclusions of various studies with respect to different UV-B application methods to improve plant resistance. In general, supplemental UV-B light has a positive effect on disease resistance in many plant-pathogen combinations, mainly through the induction of the production of specialized metabolites. However, many variables (UV-B light source, plant species, dose and intensity, timing during the day, duration, background light, etc.) make it difficult to compare and draw general conclusions. We compiled the information of recent studies on UV-B light applications, including e.g., details on the UV-B light source, experimental set-up, calculated UV-B light dose, intensity, and duration. This review provides practical insights and facilitates future research on UV-B radiation as a promising tool to reduce disease and pest incidence.
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Affiliation(s)
- Prisca Meyer
- Division of Crop Biotechnics, Department of Biosystems, KU Leuven, 3001, Leuven, Belgium
| | - Bram Van de Poel
- Division of Crop Biotechnics, Department of Biosystems, KU Leuven, 3001, Leuven, Belgium
| | - Barbara De Coninck
- Division of Crop Biotechnics, Department of Biosystems, KU Leuven, 3001, Leuven, Belgium.
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15
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Rai N, Morales LO, Aphalo PJ. Perception of solar UV radiation by plants: photoreceptors and mechanisms. PLANT PHYSIOLOGY 2021; 186:1382-1396. [PMID: 33826733 PMCID: PMC8260113 DOI: 10.1093/plphys/kiab162] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Accepted: 03/25/2021] [Indexed: 05/04/2023]
Abstract
About 95% of the ultraviolet (UV) photons reaching the Earth's surface are UV-A (315-400 nm) photons. Plant responses to UV-A radiation have been less frequently studied than those to UV-B (280-315 nm) radiation. Most previous studies on UV-A radiation have used an unrealistic balance between UV-A, UV-B, and photosynthetically active radiation (PAR). Consequently, results from these studies are difficult to interpret from an ecological perspective, leaving an important gap in our understanding of the perception of solar UV radiation by plants. Previously, it was assumed UV-A/blue photoreceptors, cryptochromes and phototropins mediated photomorphogenic responses to UV-A radiation and "UV-B photoreceptor" UV RESISTANCE LOCUS 8 (UVR8) to UV-B radiation. However, our understanding of how UV-A radiation is perceived by plants has recently improved. Experiments using a realistic balance between UV-B, UV-A, and PAR have demonstrated that UVR8 can play a major role in the perception of both UV-B and short-wavelength UV-A (UV-Asw, 315 to ∼350 nm) radiation. These experiments also showed that UVR8 and cryptochromes jointly regulate gene expression through interactions that alter the relative sensitivity to UV-B, UV-A, and blue wavelengths. Negative feedback loops on the action of these photoreceptors can arise from gene expression, signaling crosstalk, and absorption of UV photons by phenolic metabolites. These interactions explain why exposure to blue light modulates photomorphogenic responses to UV-B and UV-Asw radiation. Future studies will need to distinguish between short and long wavelengths of UV-A radiation and to consider UVR8's role as a UV-B/UV-Asw photoreceptor in sunlight.
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Affiliation(s)
- Neha Rai
- Organismal and Evolutionary Biology, Viikki Plant Science Center (ViPS), Faculty of Biological and Environmental Sciences, University of Helsinki, 00014 Helsinki, Finland
- Author for communication: . Present address: Department of Botany and Plant Biology, University of Geneva, Geneva, Switzerland
| | - Luis Orlando Morales
- School of Science and Technology, The Life Science Center-Biology, Örebro University, SE-70182 Örebro, Sweden
| | - Pedro José Aphalo
- Organismal and Evolutionary Biology, Viikki Plant Science Center (ViPS), Faculty of Biological and Environmental Sciences, University of Helsinki, 00014 Helsinki, Finland
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16
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Podolec R, Demarsy E, Ulm R. Perception and Signaling of Ultraviolet-B Radiation in Plants. ANNUAL REVIEW OF PLANT BIOLOGY 2021; 72:793-822. [PMID: 33636992 DOI: 10.1146/annurev-arplant-050718-095946] [Citation(s) in RCA: 48] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Ultraviolet-B (UV-B) radiation is an intrinsic fraction of sunlight that plants perceive through the UVR8 photoreceptor. UVR8 is a homodimer in its ground state that monomerizes upon UV-B photon absorption via distinct tryptophan residues. Monomeric UVR8 competitively binds to the substrate binding site of COP1, thus inhibiting its E3 ubiquitin ligase activity against target proteins, which include transcriptional regulators such as HY5. The UVR8-COP1 interaction also leads to the destabilization of PIF bHLH factor family members. Additionally, UVR8 directly interacts with and inhibits the DNA binding of a different set of transcription factors. Each of these UVR8 signaling mechanisms initiates nuclear gene expression changes leading to UV-B-induced photomorphogenesis and acclimation. The two WD40-repeat proteins RUP1 and RUP2 provide negative feedback regulation and inactivate UVR8 by facilitating redimerization. Here, we review the molecular mechanisms of the UVR8 pathway from UV-B perception and signal transduction to gene expression changes and physiological UV-B responses.
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Affiliation(s)
- Roman Podolec
- Department of Botany and Plant Biology, Section of Biology, Faculty of Sciences, University of Geneva, 1211 Geneva, Switzerland; , ,
- Institute of Genetics and Genomics of Geneva (iGE3), University of Geneva, 1211 Geneva, Switzerland
| | - Emilie Demarsy
- Department of Botany and Plant Biology, Section of Biology, Faculty of Sciences, University of Geneva, 1211 Geneva, Switzerland; , ,
| | - Roman Ulm
- Department of Botany and Plant Biology, Section of Biology, Faculty of Sciences, University of Geneva, 1211 Geneva, Switzerland; , ,
- Institute of Genetics and Genomics of Geneva (iGE3), University of Geneva, 1211 Geneva, Switzerland
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17
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Xiong Y, Xing Q, Müller-Xing R. A novel UV-B priming system reveals an UVR8-depedent memory, which provides resistance against UV-B stress in Arabidopsis leaves. PLANT SIGNALING & BEHAVIOR 2021; 16:1879533. [PMID: 33632077 PMCID: PMC7971206 DOI: 10.1080/15592324.2021.1879533] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Single treatment of plants with pathogens like Pseudomonas syringae can trigger systemic acquired resistance (SAR) that lasts several days to several weeks in Arabidopsis thaliana. Similar primed resistances were described for abiotic stresses like drought and heat stress. Most studies about plant resistance to ultraviolet (UV)-radiation used low UV-B radiations over a long period. These experimental designs make it difficult to distinguish acclimation effects from real cellular memory which facilitate transcriptional and other responses to a second UV-radiation after a latent phase. Here we present a novel UV-B priming system. We demonstrate that a single UV-B treatment, which causes neither visible damage nor accumulation of pigments, can stimulate resistance against UV-B stress. After a second damaging UV-B treatment, UV-primed plants showed significantly reduced damage in comparison to non-primed plants. Furthermore, the acquirement of the induced UV-B resistance was impaired in uvr8-6 mutants suggesting that the UV-B receptor is essential for UV-B stress memory in Arabidopsis. We discuss advantages and limits of our UV-B priming system which will be a powerful tool to investigate UV-B memory in future studies.
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Affiliation(s)
- Ying Xiong
- Key Laboratory of Saline-Alkali Vegetation Ecology Restoration (Northeast Forestry University), Ministry of Education, Harbin, China
- Plant Epigenetics and Development, Institute of Genetics, College of Life Science, Northeast Forestry University, Harbin, China
| | - Qian Xing
- Key Laboratory of Saline-Alkali Vegetation Ecology Restoration (Northeast Forestry University), Ministry of Education, Harbin, China
- Plant Epigenetics and Development, Institute of Genetics, College of Life Science, Northeast Forestry University, Harbin, China
| | - Ralf Müller-Xing
- Key Laboratory of Saline-Alkali Vegetation Ecology Restoration (Northeast Forestry University), Ministry of Education, Harbin, China
- Plant Epigenetics and Development, Institute of Genetics, College of Life Science, Northeast Forestry University, Harbin, China
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18
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A constitutively monomeric UVR8 photoreceptor confers enhanced UV-B photomorphogenesis. Proc Natl Acad Sci U S A 2021; 118:2017284118. [PMID: 33542100 PMCID: PMC8017708 DOI: 10.1073/pnas.2017284118] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
Coping with UV-B is crucial for plant survival in sunlight. The UV-B photoreceptor UVR8 regulates gene expression associated with photomorphogenesis, acclimation, and UV-B stress tolerance. UV-B photon reception by UVR8 homodimers results in monomerization, followed by interaction with the key signaling protein COP1. We have discovered a UV-B hypersensitive UVR8 photoreceptor that confers strongly enhanced UV-B tolerance and generated a UVR8 variant based on the underlying mutation that shows extremely enhanced constitutive signaling activity. Our findings provide key mechanistic insight into how plants respond and acclimate to UV-B radiation. The plant ultraviolet-B (UV-B) photoreceptor UVR8 plays an important role in UV-B acclimation and survival. UV-B absorption by homodimeric UVR8 induces its monomerization and interaction with the E3 ubiquitin ligase COP1, leading ultimately to gene expression changes. UVR8 is inactivated through redimerization, facilitated by RUP1 and RUP2. Here, we describe a semidominant, hyperactive allele, namely uvr8-17D, that harbors a glycine-101 to serine mutation. UVR8G101S overexpression led to weak constitutive photomorphogenesis and extreme UV-B responsiveness. UVR8G101S was observed to be predominantly monomeric in vivo and, once activated by UV-B, was not efficiently inactivated. Analysis of a UVR8 crystal structure containing the G101S mutation revealed the distortion of a loop region normally involved in stabilization of the UVR8 homodimer. Plants expressing a UVR8 variant combining G101S with the previously described W285A mutation exhibited robust constitutive photomorphogenesis. This work provides further insight into UVR8 activation and inactivation mechanisms and describes a genetic tool for the manipulation of photomorphogenic responses.
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19
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Pierik R, Ballaré CL. Control of Plant Growth and Defense by Photoreceptors: From Mechanisms to Opportunities in Agriculture. MOLECULAR PLANT 2021; 14:61-76. [PMID: 33276158 DOI: 10.1016/j.molp.2020.11.021] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Revised: 11/19/2020] [Accepted: 11/26/2020] [Indexed: 06/12/2023]
Abstract
Plants detect and respond to the proximity of competitors using light signals perceived by photoreceptor proteins. A low ratio of red to far-red radiation (R:FR ratio) is a key signal of competition that is sensed by the photoreceptor phytochrome B (phyB). Low R:FR ratios increase the synthesis of growth-related hormones, including auxin and gibberellins, promoting stem elongation and other shade-avoidance responses. Other photoreceptors that help plants to optimize their developmental configuration and resource allocation patterns in the canopy include blue light photoreceptors, such as cryptochromes and phototropins, and UV receptors, such as UVR8. All photoreceptors act by directly or indirectly controlling the activity of two major regulatory nodes for growth and development: the COP1/SPA ubiquitin E3 ligase complex and the PIF transcription factors. phyB is also an important modulator of hormonal pathways that regulate plant defense against herbivores and pathogens, including the jasmonic acid signaling pathway. In this Perspective, we discuss recent advances on the studies of the mechanisms that link photoreceptors with growth and defense. Understanding these mechanisms is important to provide a functional platform for breeding programs aimed at improving plant productivity, stress tolerance, and crop health in species of agronomic interest, and to manipulate the light environments in protected agriculture.
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Affiliation(s)
- Ronald Pierik
- Plant Ecophysiology, Department of Biology, Utrecht University, Padualaan 8, Utrecht 3584 CH, the Netherlands.
| | - Carlos L Ballaré
- IFEVA, Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad de Buenos Aires, Ave. San Martín 4453, C1417DSE, Buenos Aires, Argentina; IIBIO-INTECH, Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad Nacional de San Martín, B1650HMP, Buenos Aires, Argentina.
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