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Yáñez-Serrano AM, Corbera J, Portillo-Estrada M, Janssens IA, Llusià J, Filella I, Peñuelas J, Preece C, Sabater F, Fernández-Martínez M. Drivers of biogenic volatile organic compound emissions in hygrophytic bryophytes. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 946:174293. [PMID: 38936717 DOI: 10.1016/j.scitotenv.2024.174293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Revised: 05/16/2024] [Accepted: 06/23/2024] [Indexed: 06/29/2024]
Abstract
Bryophytes can both emit and take up biogenic volatile organic compounds (BVOCs) to and from the environment. Despite the scarce study of these exchanges, BVOCs have been shown to be important for a wide range of ecological roles. Bryophytes are the most ancient clade of land plants and preserve very similar traits to those first land colonisers. Therefore, the study of these plants can help understand the early processes of BVOC emissions as an adaptation to terrestrial life. Here, we determine the emission rates of BVOCs from different bryophyte species to understand what drives such emissions. We studied 26 bryophyte species from temperate regions that can be found in mountain springs located in NE Spain. Bryophyte BVOC emission presented no significant phylogenetic signal for any of the compounds analysed. Hence, we used mixed linear models to investigate the species-specific differences and eco-physiological and environmental drivers of bryophyte BVOC emission. In general, species-specific variability was the main factor explaining bryophyte BVOC emissions; but additionally, photosynthetic rates and light intensity increased BVOC emissions. Despite emission measurements reported here were conducted at 30°, and may not directly correspond to emission rates in natural conditions, most of the screened species have never been measured before for BVOC emissions and therefore this information can help understand the drivers of the emissions of BVOCs in bryophytes.
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Affiliation(s)
- A M Yáñez-Serrano
- IDAEA-CSIC, 08034 Barcelona, Spain; CREAF, E08193 Bellaterra (Cerdanyola del Vallès), Catalonia, Spain; CSIC, Global Ecology Unit, CREAF-CSIC-UAB, E08193 Bellaterra (Cerdanyola del Vallès), Catalonia, Spain.
| | - J Corbera
- Delegació de la Serralada Litoral Central, ICHN, Barcelona, Catalonia, Spain
| | - M Portillo-Estrada
- PLECO (Plants and Ecosystems), Department of Biology, University of Antwerp, Wilrijk, Belgium
| | - I A Janssens
- PLECO (Plants and Ecosystems), Department of Biology, University of Antwerp, Wilrijk, Belgium
| | - J Llusià
- CREAF, E08193 Bellaterra (Cerdanyola del Vallès), Catalonia, Spain; CSIC, Global Ecology Unit, CREAF-CSIC-UAB, E08193 Bellaterra (Cerdanyola del Vallès), Catalonia, Spain
| | - I Filella
- CREAF, E08193 Bellaterra (Cerdanyola del Vallès), Catalonia, Spain; CSIC, Global Ecology Unit, CREAF-CSIC-UAB, E08193 Bellaterra (Cerdanyola del Vallès), Catalonia, Spain
| | - J Peñuelas
- CREAF, E08193 Bellaterra (Cerdanyola del Vallès), Catalonia, Spain; CSIC, Global Ecology Unit, CREAF-CSIC-UAB, E08193 Bellaterra (Cerdanyola del Vallès), Catalonia, Spain
| | - C Preece
- IRTA, Torre Marimón, Caldes de Montbui, Catalonia, Spain
| | - F Sabater
- BEECA-UB, Department of Evolutionary Biology, Ecology and Environmental Sciences, University of Barcelona, E08028 Barcelona, Catalonia, Spain
| | - M Fernández-Martínez
- CREAF, E08193 Bellaterra (Cerdanyola del Vallès), Catalonia, Spain; CSIC, Global Ecology Unit, CREAF-CSIC-UAB, E08193 Bellaterra (Cerdanyola del Vallès), Catalonia, Spain; Delegació de la Serralada Litoral Central, ICHN, Barcelona, Catalonia, Spain; BEECA-UB, Department of Evolutionary Biology, Ecology and Environmental Sciences, University of Barcelona, E08028 Barcelona, Catalonia, Spain
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González-Cabanelas D, Perreca E, Rohwer JM, Schmidt A, Engl T, Raguschke B, Gershenzon J, Wright LP. Deoxyxylulose 5-Phosphate Synthase Does Not Play a Major Role in Regulating the Methylerythritol 4-Phosphate Pathway in Poplar. Int J Mol Sci 2024; 25:4181. [PMID: 38673766 PMCID: PMC11049974 DOI: 10.3390/ijms25084181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2024] [Revised: 03/26/2024] [Accepted: 03/29/2024] [Indexed: 04/28/2024] Open
Abstract
The plastidic 2-C-methylerythritol 4-phosphate (MEP) pathway supplies the precursors of a large variety of essential plant isoprenoids, but its regulation is still not well understood. Using metabolic control analysis (MCA), we examined the first enzyme of this pathway, 1-deoxyxylulose 5-phosphate synthase (DXS), in multiple grey poplar (Populus × canescens) lines modified in their DXS activity. Single leaves were dynamically labeled with 13CO2 in an illuminated, climate-controlled gas exchange cuvette coupled to a proton transfer reaction mass spectrometer, and the carbon flux through the MEP pathway was calculated. Carbon was rapidly assimilated into MEP pathway intermediates and labeled both the isoprene released and the IDP+DMADP pool by up to 90%. DXS activity was increased by 25% in lines overexpressing the DXS gene and reduced by 50% in RNA interference lines, while the carbon flux in the MEP pathway was 25-35% greater in overexpressing lines and unchanged in RNA interference lines. Isoprene emission was also not altered in these different genetic backgrounds. By correlating absolute flux to DXS activity under different conditions of light and temperature, the flux control coefficient was found to be low. Among isoprenoid end products, isoprene itself was unchanged in DXS transgenic lines, but the levels of the chlorophylls and most carotenoids measured were 20-30% less in RNA interference lines than in overexpression lines. Our data thus demonstrate that DXS in the isoprene-emitting grey poplar plays only a minor part in controlling flux through the MEP pathway.
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Affiliation(s)
- Diego González-Cabanelas
- Department of Biochemistry, Max Plank Institute for Chemical Ecology, Hans-Knöll-Straße 8, 07745 Jena, Germany; (D.G.-C.); (A.S.); (B.R.); (J.G.); (L.P.W.)
| | - Erica Perreca
- Department of Biochemistry, Max Plank Institute for Chemical Ecology, Hans-Knöll-Straße 8, 07745 Jena, Germany; (D.G.-C.); (A.S.); (B.R.); (J.G.); (L.P.W.)
| | - Johann M. Rohwer
- Laboratory for Molecular Systems Biology, Department of Biochemistry, Stellenbosch University, Private Bag X1, Matieland, Stellenbosch 7602, South Africa;
| | - Axel Schmidt
- Department of Biochemistry, Max Plank Institute for Chemical Ecology, Hans-Knöll-Straße 8, 07745 Jena, Germany; (D.G.-C.); (A.S.); (B.R.); (J.G.); (L.P.W.)
| | - Tobias Engl
- Department of Insect Symbiosis, Max Plank Institute for Chemical Ecology, Hans-Knöll-Straße 8, 07745 Jena, Germany;
| | - Bettina Raguschke
- Department of Biochemistry, Max Plank Institute for Chemical Ecology, Hans-Knöll-Straße 8, 07745 Jena, Germany; (D.G.-C.); (A.S.); (B.R.); (J.G.); (L.P.W.)
| | - Jonathan Gershenzon
- Department of Biochemistry, Max Plank Institute for Chemical Ecology, Hans-Knöll-Straße 8, 07745 Jena, Germany; (D.G.-C.); (A.S.); (B.R.); (J.G.); (L.P.W.)
| | - Louwrance P. Wright
- Department of Biochemistry, Max Plank Institute for Chemical Ecology, Hans-Knöll-Straße 8, 07745 Jena, Germany; (D.G.-C.); (A.S.); (B.R.); (J.G.); (L.P.W.)
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3
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Weraduwage SM, Whitten D, Kulke M, Sahu A, Vermaas JV, Sharkey TD. The isoprene-responsive phosphoproteome provides new insights into the putative signalling pathways and novel roles of isoprene. PLANT, CELL & ENVIRONMENT 2024; 47:1099-1117. [PMID: 38038355 DOI: 10.1111/pce.14776] [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: 08/01/2023] [Revised: 10/30/2023] [Accepted: 11/18/2023] [Indexed: 12/02/2023]
Abstract
Many plants, especially trees, emit isoprene in a highly light- and temperature-dependent manner. The advantages for plants that emit, if any, have been difficult to determine. Direct effects on membranes have been disproven. New insights have been obtained by RNA sequencing, proteomic and metabolomic studies. We determined the responses of the phosphoproteome to exposure of Arabidopsis leaves to isoprene in the gas phase for either 1 or 5 h. Isoprene effects that were not apparent from RNA sequencing and other methods but were apparent in the phosphoproteome include effects on chloroplast movement proteins and membrane remodelling proteins. Several receptor kinases were found to have altered phosphorylation levels. To test whether potential isoprene receptors could be identified, we used molecular dynamics simulations to test for proteins that might have strong binding to isoprene and, therefore might act as receptors. Although many Arabidopsis proteins were found to have slightly higher binding affinities than a reference set of Homo sapiens proteins, no specific receptor kinase was found to have a very high binding affinity. The changes in chloroplast movement, photosynthesis capacity and so forth, found in this work, are consistent with isoprene responses being especially useful in the upper canopy of trees.
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Affiliation(s)
- Sarathi M Weraduwage
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, Michigan, USA
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan, USA
- Departments of Biology and Biochemistry, Bishop's University, Sherbrooke, Quebec, Canada
| | - Douglas Whitten
- Research Technology Support Facility-Proteomics Core, Michigan State University, East Lansing, Michigan, USA
| | - Martin Kulke
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, Michigan, USA
- School of Natural Sciences, Technische Universität München, Munich, Germany
| | - Abira Sahu
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, Michigan, USA
- Plant Resilience Institute, Michigan State University, East Lansing, Michigan, USA
| | - Josh V Vermaas
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, Michigan, USA
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan, USA
| | - Thomas D Sharkey
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, Michigan, USA
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan, USA
- Plant Resilience Institute, Michigan State University, East Lansing, Michigan, USA
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Yu J, Khomenko I, Biasioli F, Li M, Varotto C. A Novel Isoprene Synthase from the Monocot Tree Copernicia prunifera (Arecaceae) Confers Enhanced Drought Tolerance in Transgenic Arabidopsis. Int J Mol Sci 2023; 24:15329. [PMID: 37895009 PMCID: PMC10607627 DOI: 10.3390/ijms242015329] [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: 08/29/2023] [Revised: 09/18/2023] [Accepted: 10/17/2023] [Indexed: 10/29/2023] Open
Abstract
The capacity to emit isoprene, among other stresses, protects plants from drought, but the molecular mechanisms underlying this trait are only partly understood. The Arecaceae (palms) constitute a very interesting model system to test the involvement of isoprene in enhancing drought tolerance, as their high isoprene emissions may have contributed to make them hyperdominant in neotropical dry forests, characterized by recurrent and extended periods of drought stress. In this study we isolated and functionally characterized a novel isoprene synthase, the gene responsible for isoprene biosynthesis, from Copernicia prunifera, a palm from seasonally dry tropical forests. When overexpressed in the non-emitter Arabidopsis thaliana, CprISPS conferred significant levels of isoprene emission, together with enhanced tolerance to water limitation throughout plant growth and development, from germination to maturity. CprISPS overexpressors displayed higher germination, cotyledon/leaf greening, water usage efficiency, and survival than WT Arabidopsis under various types of water limitation. This increased drought tolerance was accompanied by a marked transcriptional up-regulation of both ABA-dependent and ABA-independent key drought response genes. Taken together, these results demonstrate the capacity of CprISPS to enhance drought tolerance in Arabidopsis and suggest that isoprene emission could have evolved in Arecaceae as an adaptive mechanism against drought.
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Affiliation(s)
- Jiamei Yu
- Biodiversity, Ecology and Environment Area, Research and Innovation Centre, Fondazione Edmund Mach, San Michele all’Adige, 38098 Trento, Italy;
- Department of Biology, University of Padova, 35121 Padova, Italy
| | - Iuliia Khomenko
- Food and Nutrition Area, Research and Innovation Centre, Fondazione Edmund Mach, San Michele all’Adige, 38098 Trento, Italy; (I.K.); (F.B.)
| | - Franco Biasioli
- Food and Nutrition Area, Research and Innovation Centre, Fondazione Edmund Mach, San Michele all’Adige, 38098 Trento, Italy; (I.K.); (F.B.)
| | - Mingai Li
- Biodiversity, Ecology and Environment Area, Research and Innovation Centre, Fondazione Edmund Mach, San Michele all’Adige, 38098 Trento, Italy;
- National Biodiversity Future Center (NBFC), 90133 Palermo, Italy
| | - Claudio Varotto
- Biodiversity, Ecology and Environment Area, Research and Innovation Centre, Fondazione Edmund Mach, San Michele all’Adige, 38098 Trento, Italy;
- National Biodiversity Future Center (NBFC), 90133 Palermo, Italy
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Krause T, Wiesinger P, González-Cabanelas D, Lackus N, Köllner TG, Klüpfel T, Williams J, Rohwer J, Gershenzon J, Schmidt A. HDR, the last enzyme in the MEP pathway, differently regulates isoprenoid biosynthesis in two woody plants. PLANT PHYSIOLOGY 2023; 192:767-788. [PMID: 36848194 DOI: 10.1093/plphys/kiad110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 01/18/2023] [Accepted: 01/31/2023] [Indexed: 06/01/2023]
Abstract
Dimethylallyl diphosphate (DMADP) and isopentenyl diphosphate (IDP) serves as the universal C5 precursors of isoprenoid biosynthesis in plants. These compounds are formed by the last step of the 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway, catalyzed by (E)-4-hydroxy-3-methylbut-2-en-1-yl diphosphate reductase (HDR). In this study, we investigated the major HDR isoforms of two woody plant species, Norway spruce (Picea abies) and gray poplar (Populus × canescens), to determine how they regulate isoprenoid formation. Since each of these species has a distinct profile of isoprenoid compounds, they may require different proportions of DMADP and IDP with proportionally more IDP being needed to make larger isoprenoids. Norway spruce contained two major HDR isoforms differing in their occurrence and biochemical characteristics. PaHDR1 produced relatively more IDP than PaHDR2 and it encoding gene was expressed constitutively in leaves, likely serving to form substrate for production of carotenoids, chlorophylls, and other primary isoprenoids derived from a C20 precursor. On the other hand, Norway spruce PaHDR2 produced relatively more DMADP than PaHDR1 and its encoding gene was expressed in leaves, stems, and roots, both constitutively and after induction with the defense hormone methyl jasmonate. This second HDR enzyme likely forms a substrate for the specialized monoterpene (C10), sesquiterpene (C15), and diterpene (C20) metabolites of spruce oleoresin. Gray poplar contained only one dominant isoform (named PcHDR2) that produced relatively more DMADP and the gene of which was expressed in all organs. In leaves, where the requirement for IDP is high to make the major carotenoid and chlorophyll isoprenoids derived from C20 precursors, excess DMADP may accumulate, which could explain the high rate of isoprene (C5) emission. Our results provide new insights into the biosynthesis of isoprenoids in woody plants under conditions of differentially regulated biosynthesis of the precursors IDP and DMADP.
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Affiliation(s)
- Toni Krause
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Hans-Knöll-Str. 8, 07745 Jena, Germany
| | - Piera Wiesinger
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Hans-Knöll-Str. 8, 07745 Jena, Germany
| | - Diego González-Cabanelas
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Hans-Knöll-Str. 8, 07745 Jena, Germany
| | - Nathalie Lackus
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Hans-Knöll-Str. 8, 07745 Jena, Germany
| | - Tobias G Köllner
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Hans-Knöll-Str. 8, 07745 Jena, Germany
| | - Thomas Klüpfel
- Department of Atmospheric Chemistry, Max Planck Institute for Chemistry, Hahn-Meitner-Weg 1, Germany
| | - Jonathan Williams
- Department of Atmospheric Chemistry, Max Planck Institute for Chemistry, Hahn-Meitner-Weg 1, Germany
| | - Johann Rohwer
- Department of Biochemistry, Stellenbosch University, Private Bag X1, Matieland, 7602 Stellenbosch, South Africa
| | - Jonathan Gershenzon
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Hans-Knöll-Str. 8, 07745 Jena, Germany
| | - Axel Schmidt
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Hans-Knöll-Str. 8, 07745 Jena, Germany
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Cai Y, Xu C, Zheng T, Zuo Z. Thermal protection function of camphor on Cinnamomum camphora cell membrane by acting as a signaling molecule. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2023; 198:107672. [PMID: 37004435 DOI: 10.1016/j.plaphy.2023.107672] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2022] [Revised: 02/19/2023] [Accepted: 03/27/2023] [Indexed: 05/07/2023]
Abstract
Isoprenoids serve important functions in protecting plant membranes against high temperature. Cinnamomum camphora is an excellent economic tree species, and releases plenty of monoterpenes. To uncover the protective mechanism of monoterpenes on the membrane system for promoting their development and utilization as anti-high temperature agents, the membrane permeability, cell ultrastructure, membrane lipid variations and related gene expression were investigated in C. camphora fumigated with camphor, one of the main monoterpenes in the plant, after fosmidomycin (Fos) blocking the monoterpene biosynthesis under high temperature (Fos+38 °C + C). High temperature at 38 °C caused the rupture of plasma as well as chloroplast and mitochondrion membranes, deformation of chloroplasts and mitochondria, and electrolyte leakage in C. camphora. High temperature with Fos treatment (Fos+38 °C) aggravated the damage, while camphor fumigation (Fos+38 °C + C) showed alleviating effects. High temperature at 38 °C disturbed the membrane lipid equilibrium by reducing the levels of 14 phosphatidylcholine, 8 phosphatidylglycerol and 6 phosphatidylethanolamine molecules, and increasing the levels of 8 phosphatidic acid, 4 diacylglycerol, 5 phosphatidylinositol, 16 sphingomyelin and 5 ceramide phosphoethanolamine molecules. Fos+38 °C treatment primarily exhibited intensifying effects on the disturbance, while these membrane lipid levels in Fos+38 °C + C5 (5 μM camphor) treatment exhibited variation tendencies to the control at 28 °C. This should result from the expression alterations of the genes related with phospholipid biosynthesis, fatty acid metabolism, and sphingolipid metabolism. It can be speculated that camphor can maintain membrane lipid stabilization in C. camphora under high temperature by acting as a signaling molecule.
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Affiliation(s)
- Yuyan Cai
- State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Hangzhou, 311300, China; Zhejiang Provincial Key Laboratory of Forest Aromatic Plants-based Healthcare Functions, Zhejiang A&F University, Hangzhou, 311300, China
| | - Chenyi Xu
- State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Hangzhou, 311300, China; Zhejiang Provincial Key Laboratory of Forest Aromatic Plants-based Healthcare Functions, Zhejiang A&F University, Hangzhou, 311300, China
| | - Tiefeng Zheng
- State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Hangzhou, 311300, China; Zhejiang Provincial Key Laboratory of Forest Aromatic Plants-based Healthcare Functions, Zhejiang A&F University, Hangzhou, 311300, China
| | - Zhaojiang Zuo
- State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Hangzhou, 311300, China; Zhejiang Provincial Key Laboratory of Forest Aromatic Plants-based Healthcare Functions, Zhejiang A&F University, Hangzhou, 311300, China.
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Weraduwage SM, Sahu A, Kulke M, Vermaas JV, Sharkey TD. Characterization of promoter elements of isoprene-responsive genes and the ability of isoprene to bind START domain transcription factors. PLANT DIRECT 2023; 7:e483. [PMID: 36742092 PMCID: PMC9889695 DOI: 10.1002/pld3.483] [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: 12/08/2022] [Accepted: 01/12/2023] [Indexed: 06/18/2023]
Abstract
Isoprene has recently been proposed to be a signaling molecule that can enhance tolerance of both biotic and abiotic stress. Not all plants make isoprene, but all plants tested to date respond to isoprene. We hypothesized that isoprene interacts with existing signaling pathways rather than requiring novel mechanisms for its effect on plants. We analyzed the cis-regulatory elements (CREs) in promoters of isoprene-responsive genes and the corresponding transcription factors binding these promoter elements to obtain clues about the transcription factors and other proteins involved in isoprene signaling. Promoter regions of isoprene-responsive genes were characterized using the Arabidopsis cis-regulatory element database. CREs bind ARR1, Dof, DPBF, bHLH112, GATA factors, GT-1, MYB, and WRKY transcription factors, and light-responsive elements were overrepresented in promoters of isoprene-responsive genes; CBF-, HSF-, WUS-binding motifs were underrepresented. Transcription factors corresponding to CREs overrepresented in promoters of isoprene-responsive genes were mainly those important for stress responses: drought-, salt/osmotic-, oxidative-, herbivory/wounding and pathogen-stress. More than half of the isoprene-responsive genes contained at least one binding site for TFs of the class IV (homeodomain leucine zipper) HD-ZIP family, such as GL2, ATML1, PDF2, HDG11, ATHB17. While the HD-zipper-loop-zipper (ZLZ) domain binds to the L1 box of the promoter region, a special domain called the steroidogenic acute regulatory protein-related lipid transfer, or START domain, can bind ligands such as fatty acids (e.g., linolenic and linoleic acid). We tested whether isoprene might bind in such a START domain. Molecular simulations and modeling to test interactions between isoprene and a class IV HD-ZIP family START-domain-containing protein were carried out. Without membrane penetration by the HDG11 START domain, isoprene within the lipid bilayer was inaccessible to this domain, preventing protein interactions with membrane bound isoprene. The cross-talk between isoprene-mediated signaling and other growth regulator and stress signaling pathways, in terms of common CREs and transcription factors could enhance the stability of the isoprene emission trait when it evolves in a plant but so far it has not been possible to say what how isoprene is sensed to initiate signaling responses.
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Affiliation(s)
- Sarathi M. Weraduwage
- MSU‐DOE Plant Research LaboratoryMichigan State UniversityEast LansingMichiganUSA
- Department of Biochemistry and Molecular BiologyMichigan State UniversityEast LansingMichiganUSA
- Great Lakes Bioenergy Research CenterMichigan State UniversityEast LansingMichiganUSA
| | - Abira Sahu
- MSU‐DOE Plant Research LaboratoryMichigan State UniversityEast LansingMichiganUSA
| | - Martin Kulke
- MSU‐DOE Plant Research LaboratoryMichigan State UniversityEast LansingMichiganUSA
- Department of Biochemistry and Molecular BiologyMichigan State UniversityEast LansingMichiganUSA
| | - Josh V. Vermaas
- MSU‐DOE Plant Research LaboratoryMichigan State UniversityEast LansingMichiganUSA
- Department of Biochemistry and Molecular BiologyMichigan State UniversityEast LansingMichiganUSA
| | - Thomas D. Sharkey
- MSU‐DOE Plant Research LaboratoryMichigan State UniversityEast LansingMichiganUSA
- Department of Biochemistry and Molecular BiologyMichigan State UniversityEast LansingMichiganUSA
- Great Lakes Bioenergy Research CenterMichigan State UniversityEast LansingMichiganUSA
- Plant Resilience InstituteMichigan State UniversityEast LansingMichiganUSA
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8
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Xu C, Wang B, Luo Q, Ma Y, Zheng T, Wang Y, Cai Y, Zuo Z. The uppermost monoterpenes improving Cinnamomum camphora thermotolerance by serving signaling functions. FRONTIERS IN PLANT SCIENCE 2022; 13:1072931. [PMID: 36589079 PMCID: PMC9800025 DOI: 10.3389/fpls.2022.1072931] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Accepted: 11/28/2022] [Indexed: 05/23/2023]
Abstract
Terpenes serve important functions in enhancing plant thermotolerance. Cinnamomum camphora mainly has eucalyptol (EuL), camphor (CmR), linalool (LnL) and borneol (BeL) chemotypes basing on the uppermost monoterpenes. To reveal the thermotolerance mechanisms of these uppermost monoterpenes (eucalyptol, camphor, linalool, and borneol) in C. camphora, we surveyed the ROS metabolism and photosynthesis in the 4 chemotypes fumigated with the corresponding uppermost monoterpene after fosmidomycin (Fos) inhibiting monoterpene synthesis under high temperature at 38°C (Fos+38°C+monoterpene), and investigated the related gene expression in EuL and CmR. Meanwhile, the thermotolerance differences among the 4 uppermost monoterpenes were analyzed. In contrast to normal temperature (28°C), ROS levels and antioxidant enzyme activities in the 4 chemotypes increased under 38°C, and further increased in the treatment with Fos inhibiting monoterpene synthesis at 38°C (Fos+38°C), which may be caused by the alterations in expression of the genes related with non-enzymatic and enzymatic antioxidant formation according to the analyses in EuL and CmR. Compared with Fos+38°C treatment, Fos+38°C+monoterpene treatments lowered ROS levels and antioxidant enzyme activities for the increased non-enzymatic antioxidant gene expression and decreased enzymatic antioxidant gene expression, respectively. High temperature at 38°C reduced the chlorophyll and carotenoid content as well as photosynthetic abilities, which may result from the declined expression of the genes associated with photosynthetic pigment biosynthesis, light reaction, and carbon fixation. Fos+38°C treatment aggravated the reduction. In contrast to Fos+38°C treatment, Fos+38°C+monoterpene treatments increased photosynthetic pigment content and improved photosynthetic abilities by up-regulating related gene expression. Among the 4 uppermost monoterpenes, camphor showed strong abilities in lowering ROS and maintaining photosynthesis, while eucalyptol showed weak abilities. This was consistent with the recovery effects of the gene expression in the treatments with camphor and eucalyptol fumigation. Therefore, the uppermost monoterpenes can enhance C. camphora thermotolerance as signaling molecules, and may have differences in the signaling functions.
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Affiliation(s)
- Chenyi Xu
- State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Hangzhou, China
- Zhejiang Provincial Key Laboratory of Forest Aromatic Plants-based Healthcare Functions, Zhejiang A&F University, Hangzhou, China
| | - Bin Wang
- State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Hangzhou, China
- Zhejiang Provincial Key Laboratory of Forest Aromatic Plants-based Healthcare Functions, Zhejiang A&F University, Hangzhou, China
| | - Qingyun Luo
- State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Hangzhou, China
- Zhejiang Provincial Key Laboratory of Forest Aromatic Plants-based Healthcare Functions, Zhejiang A&F University, Hangzhou, China
| | - Yuandan Ma
- State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Hangzhou, China
- Zhejiang Provincial Key Laboratory of Forest Aromatic Plants-based Healthcare Functions, Zhejiang A&F University, Hangzhou, China
| | - Tiefeng Zheng
- State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Hangzhou, China
- Zhejiang Provincial Key Laboratory of Forest Aromatic Plants-based Healthcare Functions, Zhejiang A&F University, Hangzhou, China
| | - Yingying Wang
- State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Hangzhou, China
- Zhejiang Provincial Key Laboratory of Forest Aromatic Plants-based Healthcare Functions, Zhejiang A&F University, Hangzhou, China
| | - Yuyan Cai
- State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Hangzhou, China
- Zhejiang Provincial Key Laboratory of Forest Aromatic Plants-based Healthcare Functions, Zhejiang A&F University, Hangzhou, China
| | - Zhaojiang Zuo
- State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Hangzhou, China
- Zhejiang Provincial Key Laboratory of Forest Aromatic Plants-based Healthcare Functions, Zhejiang A&F University, Hangzhou, China
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9
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Abbas F, O'Neill Rothenberg D, Zhou Y, Ke Y, Wang HC. Volatile organic compounds as mediators of plant communication and adaptation to climate change. PHYSIOLOGIA PLANTARUM 2022; 174:e13840. [PMID: 36512339 DOI: 10.1111/ppl.13840] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Revised: 11/18/2022] [Accepted: 12/08/2022] [Indexed: 06/17/2023]
Abstract
Plant volatile organic compounds are the most abundant and structurally diverse plant secondary metabolites. They play a key role in plant lifespan via direct and indirect plant defenses, attracting pollinators, and mediating various interactions between plants and their environment. The ecological diversity and context-dependence of plant-plant communication driven by volatiles are crucial elements that influence plant performance in different habitats. Plant volatiles are also valued for their multiple applications in food, flavor, pharmaceutical, and cosmetics industries. In the current review, we summarize recent advances that have elucidated the functions of plant volatile organic compounds as mediators of plant interaction at community and individual levels, highlighting the complexities of plant receiver feedback to various signals and cues. This review emphasizes volatile terpenoids, the most abundant class of plant volatile organic compounds, highlighting their role in plant adaptability to global climate change and stress-response pathways that are integral to plant growth and survival. Finally, we identify research gaps and suggest future research directions.
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Affiliation(s)
- Farhat Abbas
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops-South China/Guangdong Litchi Engineering Research Center, College of Horticulture, South China Agricultural University, Guangzhou, China
| | - Dylan O'Neill Rothenberg
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops-South China/Guangdong Litchi Engineering Research Center, College of Horticulture, South China Agricultural University, Guangzhou, China
| | - Yiwei Zhou
- Guangdong Key Laboratory of Ornamental Plant Germplasm Innovation and Utilization, Environmental Horticulture Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, China
| | - Yanguo Ke
- College of Agriculture and Life Sciences, Yunnan Urban Agricultural Engineering & Technological Research Center, Kunming University, Kunming, China
- College of Economics and Management, Kunming University, Kunming, China
| | - Hui-Cong Wang
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops-South China/Guangdong Litchi Engineering Research Center, College of Horticulture, South China Agricultural University, Guangzhou, China
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10
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Lazazzara V, Avesani S, Robatscher P, Oberhuber M, Pertot I, Schuhmacher R, Perazzolli M. Biogenic volatile organic compounds in the grapevine response to pathogens, beneficial microorganisms, resistance inducers, and abiotic factors. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:529-554. [PMID: 34409450 DOI: 10.1093/jxb/erab367] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2021] [Accepted: 08/04/2021] [Indexed: 06/13/2023]
Abstract
The synthesis of volatile organic compounds (VOCs) in plants is triggered in response to external stimuli, and these compounds can migrate to distal tissues and neighbouring receivers. Although grapevine VOCs responsible for wine aroma and plant-insect communications are well characterized, functional properties of VOCs produced in response to phytopathogens, beneficial microorganisms, resistance inducers, and abiotic factors have been less studied. In this review, we focused on the emission patterns and potential biological functions of VOCs produced by grapevines in response to stimuli. Specific grapevine VOCs are emitted in response to the exogenous stimulus, suggesting their precise involvement in plant defence response. VOCs with inhibitory activities against pathogens and responsible for plant resistance induction are reported, and some of them can also be used as biomarkers of grapevine resistance. Likewise, VOCs produced in response to beneficial microorganisms and environmental factors are possible mediators of grapevine-microbe communications and abiotic stress tolerance. Although further functional studies may improve our knowledge, the existing literature suggests that VOCs have an underestimated potential application as pathogen inhibitors, resistance inducers against biotic or abiotic stresses, signalling molecules, membrane stabilizers, and modulators of reactive oxygen species. VOC patterns could also be used to screen for resistant traits or to monitor the plant physiological status.
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Affiliation(s)
- Valentina Lazazzara
- Research and Innovation Centre, Fondazione Edmund Mach, Via E. Mach 1, 38098 San Michele all'Adige, Italy
| | - Sara Avesani
- Research and Innovation Centre, Fondazione Edmund Mach, Via E. Mach 1, 38098 San Michele all'Adige, Italy
- Center for Agriculture Food Environment (C3A), University of Trento, Via E. Mach 1, 38098 San Michele all'Adige, Italy
- Laboratory for Flavours and Metabolites, Laimburg Research Centre, Laimburg 6, Pfatten (Vadena), 39040 Auer (Ora), Italy
| | - Peter Robatscher
- Laboratory for Flavours and Metabolites, Laimburg Research Centre, Laimburg 6, Pfatten (Vadena), 39040 Auer (Ora), Italy
| | - Michael Oberhuber
- Laboratory for Flavours and Metabolites, Laimburg Research Centre, Laimburg 6, Pfatten (Vadena), 39040 Auer (Ora), Italy
| | - Ilaria Pertot
- Research and Innovation Centre, Fondazione Edmund Mach, Via E. Mach 1, 38098 San Michele all'Adige, Italy
- Center for Agriculture Food Environment (C3A), University of Trento, Via E. Mach 1, 38098 San Michele all'Adige, Italy
| | - Rainer Schuhmacher
- Institute of Bioanalytics and Agro-Metabolomics, Department of Agrobiotechnology (IFA-Tulln), University of Natural Resources and Life Sciences, Vienna (BOKU), Konrad-Lorenz-Straße 20, 3430 Tulln, Austria
| | - Michele Perazzolli
- Research and Innovation Centre, Fondazione Edmund Mach, Via E. Mach 1, 38098 San Michele all'Adige, Italy
- Center for Agriculture Food Environment (C3A), University of Trento, Via E. Mach 1, 38098 San Michele all'Adige, Italy
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11
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Kreuzwieser J, Meischner M, Grün M, Yáñez-Serrano AM, Fasbender L, Werner C. Drought affects carbon partitioning into volatile organic compound biosynthesis in Scots pine needles. THE NEW PHYTOLOGIST 2021; 232:1930-1943. [PMID: 34523149 DOI: 10.1111/nph.17736] [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] [Received: 02/23/2021] [Accepted: 09/03/2021] [Indexed: 06/13/2023]
Abstract
The effect of drought on the interplay of processes controlling carbon partitioning into plant primary and secondary metabolisms, such as respiratory CO2 release and volatile organic compound (VOC) biosynthesis, is not fully understood. To elucidate the effect of drought on the fate of cellular C sources into VOCs vs CO2 , we conducted tracer experiments with 13 CO2 and position-specific 13 C-labelled pyruvate, a key metabolite between primary and secondary metabolisms, in Scots pine seedlings. We determined the stable carbon isotope composition of leaf exchanged CO2 and VOC. Drought reduced the emission of the sesquiterpenes α-farnesene and β-farnesene but did not affect 13 C-incorporation from 13 C-pyruvate. The labelling patterns suggest that farnesene biosynthesis partially depends on isopentenyl diphosphate crosstalk between chloroplasts and cytosol, and that drought inhibits this process. Contrary to sesquiterpenes, drought did not affect emission of isoprene, monoterpenes and some oxygenated compounds. During the day, pyruvate was used in the TCA cycle to a minor degree but was mainly consumed in pathways of secondary metabolism. Drought partly inhibited such pathways, while allocation into the TCA cycle increased. Drought caused a re-direction of pyruvate consuming pathways, which contributed to maintenance of isoprene and monoterpene production despite strongly inhibited photosynthesis. This underlines the importance of these volatiles for stress tolerance.
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Affiliation(s)
- Jürgen Kreuzwieser
- Chair of Ecosystem Physiology, Albert-Ludwigs-Universität Freiburg, Freiburg, 79110, Germany
| | - Mirjam Meischner
- Chair of Ecosystem Physiology, Albert-Ludwigs-Universität Freiburg, Freiburg, 79110, Germany
| | - Michel Grün
- Chair of Ecosystem Physiology, Albert-Ludwigs-Universität Freiburg, Freiburg, 79110, Germany
| | - Ana Maria Yáñez-Serrano
- Institute of Environmental Assessment and Water Research (IDAEA), Spanish Research Council (CSIC), Barcelona, 08034, Spain
- Center for Ecological Research and Forestry Applications (CREAF), Cerdanyola del Vallès, 08193, Spain
- Global Ecology Unit, CREAF-CSIC-UAB, Cerdanyola del Vallès, 08193, Spain
| | - Lukas Fasbender
- Chair of Ecosystem Physiology, Albert-Ludwigs-Universität Freiburg, Freiburg, 79110, Germany
| | - Christiane Werner
- Chair of Ecosystem Physiology, Albert-Ludwigs-Universität Freiburg, Freiburg, 79110, Germany
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12
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Gibson L, Crombie AT, McNamara NP, Murrell JC. Isoprene-degrading bacteria associated with the phyllosphere of Salix fragilis, a high isoprene-emitting willow of the Northern Hemisphere. ENVIRONMENTAL MICROBIOME 2021; 16:17. [PMID: 34446108 PMCID: PMC8394569 DOI: 10.1186/s40793-021-00386-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Accepted: 08/12/2021] [Indexed: 05/13/2023]
Abstract
BACKGROUND Isoprene accounts for about half of total biogenic volatile organic compound emissions globally, and as a climate active gas it plays a significant and varied role in atmospheric chemistry. Terrestrial plants are the largest source of isoprene, with willow (Salix) making up one of the most active groups of isoprene producing trees. Bacteria act as a biological sink for isoprene and those bacteria associated with high isoprene-emitting trees may provide further insight into its biodegradation. RESULTS A DNA-SIP experiment incubating willow (Salix fragilis) leaves with 13C-labelled isoprene revealed an abundance of Comamonadaceae, Methylobacterium, Mycobacterium and Polaromonas in the isoprene degrading community when analysed by 16S rRNA gene amplicon sequencing. Metagenomic analysis of 13C-enriched samples confirmed the abundance of Comamonadaceae, Acidovorax, Polaromonas, Variovorax and Ramlibacter. Mycobacterium and Methylobacterium were also identified after metagenomic analysis and a Mycobacterium metagenome-assembled genome (MAG) was recovered. This contained two complete isoprene degradation metabolic gene clusters, along with a propane monooxygenase gene cluster. Analysis of the abundance of the alpha subunit of the isoprene monooxygenase, isoA, in unenriched DNA samples revealed that isoprene degraders associated with willow leaves are abundant, making up nearly 0.2% of the natural bacterial community. CONCLUSIONS Analysis of the isoprene degrading community associated with willow leaves using DNA-SIP and focused metagenomics techniques enabled recovery of the genome of an active isoprene-degrading Mycobacterium species and provided valuable insight into bacteria involved in degradation of isoprene on the leaves of a key species of isoprene-emitting tree in the northern hemisphere.
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Affiliation(s)
- Lisa Gibson
- School of Environmental Sciences, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK.
| | - Andrew T Crombie
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK
| | - Niall P McNamara
- Centre of Ecology and Hydrology, Lancaster University, Bailrigg, Lancaster, LA1 4AP, UK
| | - J Colin Murrell
- School of Environmental Sciences, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK.
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13
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Wedow JM, Ainsworth EA, Li S. Plant biochemistry influences tropospheric ozone formation, destruction, deposition, and response. Trends Biochem Sci 2021; 46:992-1002. [PMID: 34303585 DOI: 10.1016/j.tibs.2021.06.007] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Revised: 06/14/2021] [Accepted: 06/29/2021] [Indexed: 10/20/2022]
Abstract
Tropospheric ozone (O3) is among the most damaging air pollutant to plants. Plants alter the atmospheric O3 concentration in two distinct ways: (i) by the emission of volatile organic compounds (VOCs) that are precursors of O3; and (ii) by dry deposition, which includes diffusion of O3 into vegetation through stomata and destruction by nonstomatal pathways. Isoprene, monoterpenes, and higher terpenoids are emitted by plants in quantities that alter tropospheric O3. Deposition of O3 into vegetation is related to stomatal conductance, leaf structural traits, and the detoxification capacity of the apoplast. The biochemical fate of O3 once it enters leaves and reacts with aqueous surfaces is largely unknown, but new techniques for the tracking and identification of initial products have the potential to open the black box.
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Affiliation(s)
- Jessica M Wedow
- Donald Danforth Plant Science Center, St. Louis, MO 63132, USA
| | - Elizabeth A Ainsworth
- USDA ARS Global Change and Photosynthesis Research Unit, Urbana, IL 61801, USA; Center for Advanced Bioenergy and Bioproducts Innovation, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Shuai Li
- Center for Advanced Bioenergy and Bioproducts Innovation, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA.
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14
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Isoprene: An Antioxidant Itself or a Molecule with Multiple Regulatory Functions in Plants? Antioxidants (Basel) 2021; 10:antiox10050684. [PMID: 33925614 PMCID: PMC8146742 DOI: 10.3390/antiox10050684] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 04/16/2021] [Accepted: 04/26/2021] [Indexed: 12/25/2022] Open
Abstract
Isoprene (C5H8) is a small lipophilic, volatile organic compound (VOC), synthesized in chloroplasts of plants through the photosynthesis-dependent 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway. Isoprene-emitting plants are better protected against thermal and oxidative stresses but only about 20% of the terrestrial plants are able to synthesize isoprene. Many studies have been performed to understand the still elusive isoprene protective mechanism. Isoprene reacts with, and quenches, many harmful reactive oxygen species (ROS) like singlet oxygen (1O2). A role for isoprene as antioxidant, made possible by its reduced state and conjugated double bonds, has been often suggested, and sometimes demonstrated. However, as isoprene is present at very low concentrations compared to other molecules, its antioxidant role is still controversial. Here we review updated evidences on the function(s) of isoprene, and outline contrasting indications on whether isoprene is an antioxidant directly scavenging ROS, or a membrane strengthener, or a modulator of genomic, proteomic and metabolomic profiles (perhaps as a secondary effect of ROS removal) eventually leading to priming of antioxidant plant defenses, or a signal of stress for neighbor plants alike other VOCs, or a hormone-like molecule, controlling the metabolic flux of other hormones made by the MEP pathway, or acting itself as a growth and development hormone.
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15
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Paoletti E, Hoshika Y, Arab L, Martini S, Cotrozzi L, Weber D, Ache P, Neri L, Baraldi R, Pellegrini E, Müller HM, Hedrich R, Alfarraj S, Rennenberg H. Date palm responses to a chronic, realistic ozone exposure in a FACE experiment. ENVIRONMENTAL RESEARCH 2021; 195:110868. [PMID: 33581095 DOI: 10.1016/j.envres.2021.110868] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 02/03/2021] [Accepted: 02/06/2021] [Indexed: 06/12/2023]
Abstract
Date palms are highly economically important species in hot arid regions, which may suffer ozone (O3) pollution equivalently to heat and water stress. However, little is known about date palm sensitivity to O3. Therefore, to identify their resistance mechanisms against elevated O3, physiological parameters (leaf gas exchange, chlorophyll fluorescence and leaf pigments) and biomass growth responses to realistic O3 exposure were tested in an isoprene-emitting date palm (Phoenix dactylifera L. cv. Nabut Saif) by a Free-Air Controlled Exposure (FACE) facility with three levels of O3 (ambient [AA, 45 ppb as 24-h average], 1.5 x AA and 2 x AA). We found a reduction of photosynthesis only at 2 x AA although some foliar traits known as early indicators of O3 stress responded already at 1.5 x AA, such as increased dark respiration, reduced leaf pigment content, reduced maximum quantum yield of PSII, inactivation of the oxygen evolving complex of PSII and reduced performance index PITOT. As a result, O3 did not affect most of the growth parameters although significant declines of root biomass occurred only at 2 x AA. The major mechanism in date palm for reducing the severity of O3 impacts was a restriction of stomatal O3 uptake due to low stomatal conductance and O3-induced stomatal closure. In addition, an increased respiration in elevated O3 may indicate an enhanced capacity of catabolizing metabolites for detoxification and repair. Interestingly, date palm produced low amounts of monoterpenes, whose emission was stimulated in 2 x AA, although isoprene emission declined at both 1.5 and 2 x AA. Our results warrant more research on a biological significance of terpenoids in plant resistance against O3 stress.
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Affiliation(s)
- Elena Paoletti
- IRET-CNR, Via Madonna Del Piano 10, 50019, Sesto Fiorentino Firenze, Italy
| | - Yasutomo Hoshika
- IRET-CNR, Via Madonna Del Piano 10, 50019, Sesto Fiorentino Firenze, Italy.
| | - Leila Arab
- Chair of Tree Physiology, Institute of Forest Sciences, Albert-Ludwigs-Universität Freiburg, Georges-Köhler-Allee 53, 79110, Freiburg, Germany
| | - Sofia Martini
- IRET-CNR, Via Madonna Del Piano 10, 50019, Sesto Fiorentino Firenze, Italy
| | - Lorenzo Cotrozzi
- Department of Agriculture, Food and Environment, University of Pisa, Via Del Borghetto 80, 56124, Pisa, Italy
| | - Daniel Weber
- Chair of Tree Physiology, Institute of Forest Sciences, Albert-Ludwigs-Universität Freiburg, Georges-Köhler-Allee 53, 79110, Freiburg, Germany; Phytoprove Pflanzenanalytik, Georg-Voigt-Str. 14-16, 60325, Frankfurt Am Main, Germany
| | - Peter Ache
- Institute for Molecular Plant Physiology and Biophysics, Biocenter, University of Würzburg, 97082, Würzburg, Germany
| | - Luisa Neri
- IBE-CNR, Via Piero Gobetti 101, 40129, Bologna, Italy
| | - Rita Baraldi
- IBE-CNR, Via Piero Gobetti 101, 40129, Bologna, Italy
| | - Elisa Pellegrini
- Department of Agriculture, Food and Environment, University of Pisa, Via Del Borghetto 80, 56124, Pisa, Italy
| | - Heike M Müller
- Institute for Molecular Plant Physiology and Biophysics, Biocenter, University of Würzburg, 97082, Würzburg, Germany
| | - Rainer Hedrich
- Institute for Molecular Plant Physiology and Biophysics, Biocenter, University of Würzburg, 97082, Würzburg, Germany; King Saud University, PO Box 2455, Riyadh, 11451, Saudi Arabia
| | - Saleh Alfarraj
- King Saud University, PO Box 2455, Riyadh, 11451, Saudi Arabia
| | - Heinz Rennenberg
- Chair of Tree Physiology, Institute of Forest Sciences, Albert-Ludwigs-Universität Freiburg, Georges-Köhler-Allee 53, 79110, Freiburg, Germany; Center of Molecular Ecophysiology (CMEP), College of Resources and Environment, Southwest University No. 2, Tiansheng Road, Beibei District, 400715, Chongqing, PR China
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16
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Bertamini M, Faralli M, Varotto C, Grando MS, Cappellin L. Leaf Monoterpene Emission Limits Photosynthetic Downregulation under Heat Stress in Field-Grown Grapevine. PLANTS 2021; 10:plants10010181. [PMID: 33478116 PMCID: PMC7835969 DOI: 10.3390/plants10010181] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 01/12/2021] [Accepted: 01/13/2021] [Indexed: 11/16/2022]
Abstract
Rising temperature is among the most remarkably stressful phenomena induced by global climate changes with negative impacts on crop productivity and quality. It has been previously shown that volatiles belonging to the isoprenoid family can confer protection against abiotic stresses. In this work, two Vitis vinifera cv. 'Chardonnay' clones (SMA130 and INRA809) differing due to a mutation (S272P) of the DXS gene encoding for 1-deoxy-D-xylulose-5-phosphate (the first dedicated enzyme of the 2C-methyl-D-erythritol-4-phosphate (MEP) pathway) and involved in the regulation of isoprenoids biosynthesis were investigated in field trials and laboratory experiments. Leaf monoterpene emission, chlorophyll fluorescence and gas-exchange measurements were assessed over three seasons at different phenological stages and either carried out in in vivo or controlled conditions under contrasting temperatures. A significant (p < 0.001) increase in leaf monoterpene emission was observed in INRA809 when plants were experiencing high temperatures and over two experiments, while no differences were recorded for SMA130. Significant variation was observed for the rate of leaf CO2 assimilation under heat stress, with INRA809 maintaining higher photosynthetic rates and stomatal conductance values than SMA130 (p = 0.003) when leaf temperature increased above 30 °C. At the same time, the maximum photochemical quantum yield of PSII (Fv/Fm) was affected by heat stress in the non-emitting clone (SMA130), while the INRA809 showed a significant resilience of PSII under elevated temperature conditions. Consistent data were recorded between field seasons and temperature treatments in controlled environment conditions, suggesting a strong influence of monoterpene emission on heat tolerance under high temperatures. This work provides further insights on the photoprotective role of isoprenoids in heat-stressed Vitis vinifera, and additional studies should focus on unraveling the mechanisms underlying heat tolerance on the monoterpene-emitter grapevine clone.
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Affiliation(s)
- Massimo Bertamini
- Center Agriculture Food Environment (C3A), University of Trento, Via. E. Mach 1, 38010 San Michele all’Adige, Italy;
- Research and Innovation Centre, Fondazione Edmund Mach, Via E. Mach 1, 38010 San Michele all’Adige, Italy; (C.V.); (L.C.)
- Correspondence: (M.B.); (M.F.)
| | - Michele Faralli
- Research and Innovation Centre, Fondazione Edmund Mach, Via E. Mach 1, 38010 San Michele all’Adige, Italy; (C.V.); (L.C.)
- Correspondence: (M.B.); (M.F.)
| | - Claudio Varotto
- Research and Innovation Centre, Fondazione Edmund Mach, Via E. Mach 1, 38010 San Michele all’Adige, Italy; (C.V.); (L.C.)
| | - Maria Stella Grando
- Center Agriculture Food Environment (C3A), University of Trento, Via. E. Mach 1, 38010 San Michele all’Adige, Italy;
- Research and Innovation Centre, Fondazione Edmund Mach, Via E. Mach 1, 38010 San Michele all’Adige, Italy; (C.V.); (L.C.)
| | - Luca Cappellin
- Research and Innovation Centre, Fondazione Edmund Mach, Via E. Mach 1, 38010 San Michele all’Adige, Italy; (C.V.); (L.C.)
- Department of Chemical Sciences, University of Padua, Via Marzolo 1, 35131 Padova, Italy
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17
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Leaf isoprene emission as a trait that mediates the growth-defense tradeoff in the face of climate stress. Oecologia 2021; 197:885-902. [PMID: 33420520 DOI: 10.1007/s00442-020-04813-7] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2020] [Accepted: 12/01/2020] [Indexed: 12/27/2022]
Abstract
Plant isoprene emissions are known to contribute to abiotic stress tolerance, especially during episodes of high temperature and drought, and during cellular oxidative stress. Recent studies have shown that genetic transformations to add or remove isoprene emissions cause a cascade of cellular modifications that include known signaling pathways, and interact to remodel adaptive growth-defense tradeoffs. The most compelling evidence for isoprene signaling is found in the shikimate and phenylpropanoid pathways, which produce salicylic acid, alkaloids, tannins, anthocyanins, flavonols and other flavonoids; all of which have roles in stress tolerance and plant defense. Isoprene also influences key gene expression patterns in the terpenoid biosynthetic pathways, and the jasmonic acid, gibberellic acid and cytokinin signaling networks that have important roles in controlling inducible defense responses and influencing plant growth and development, particularly following defoliation. In this synthesis paper, using past studies of transgenic poplar, tobacco and Arabidopsis, we present the evidence for isoprene acting as a metabolite that coordinates aspects of cellular signaling, resulting in enhanced chemical defense during periods of climate stress, while minimizing costs to growth. This perspective represents a major shift in our thinking away from direct effects of isoprene, for example, by changing membrane properties or quenching ROS, to indirect effects, through changes in gene expression and protein abundances. Recognition of isoprene's role in the growth-defense tradeoff provides new perspectives on evolution of the trait, its contribution to plant adaptation and resilience, and the ecological niches in which it is most effective.
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18
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Sun Z, Shen Y, Niinemets Ü. Responses of isoprene emission and photochemical efficiency to severe drought combined with prolonged hot weather in hybrid Populus. JOURNAL OF EXPERIMENTAL BOTANY 2020; 71:7364-7381. [PMID: 32996573 PMCID: PMC7906789 DOI: 10.1093/jxb/eraa415] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Accepted: 09/06/2020] [Indexed: 06/11/2023]
Abstract
Isoprene emissions have been considered as a protective response of plants to heat stress, but there is limited information of how prolonged heat spells affect isoprene emission capacity, particularly under the drought conditions that often accompany hot weather. Under combined long-term stresses, presence of isoprene emission could contribute to the maintenance of the precursor pool for rapid synthesis of essential isoprenoids to repair damaged components of leaf photosynthetic apparatus. We studied changes in leaf isoprene emission rate, photosynthetic characteristics, and antioxidant enzyme activities in two hybrid Populus clones, Nanlin 1388 (relatively high drought tolerance) and Nanlin 895 (relatively high thermotolerance) that were subjected to long-term (30 d) soil water stress (25% versus 90% soil field capacity) combined with a natural heat spell (day-time temperatures of 35-40 °C) that affected both control and water-stressed plants. Unexpectedly, isoprene emissions from both the clones were similar and the overall effects of drought on the emission characteristics were initially minor; however, treatment effects and clonal differences increased with time. In particular, the isoprene emission rate only increased slightly in the Nanlin 895 control plants after 15 d of treatment, whereas it decreased by more than 5-fold in all treatment × clone combinations after 30 d. The reduction in isoprene emission rate was associated with a decrease in the pool size of the isoprene precursor dimethylallyl diphosphate in all cases at 30 d after the start of treatment. Net assimilation rate, stomatal conductance, the openness of PSII centers, and the effective quantum yield all decreased, and non-photochemical quenching and catalase activity increased in both control and water-stressed plants. Contrary to the hypothesis of protection of leaf photosynthetic apparatus by isoprene, the data collectively indicated that prolonged stress affected isoprene emissions more strongly than leaf photosynthetic characteristics. This primarily reflected the depletion of isoprene precursor pools under long-term severe stress.
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Affiliation(s)
- Zhihong Sun
- School of Forestry and Bio-Technology, Zhejiang A&F University, Hangzhou, Zhejiang, China
- Zhejiang A&F University State Key Laboratory of Subtropical Silviculture, Hangzhou, Zhejiang, China
| | - Yan Shen
- School of Forestry and Bio-Technology, Zhejiang A&F University, Hangzhou, Zhejiang, China
| | - Ülo Niinemets
- School of Forestry and Bio-Technology, Zhejiang A&F University, Hangzhou, Zhejiang, China
- Institute of Agricultural and Environmental Sciences, Estonian University of Life Sciences, Kreutzwaldi, Tartu, Estonia
- Estonian Academy of Sciences, Kohtu, Tallinn, Estonia
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Faralli M, Li M, Varotto C. Shoot Characterization of Isoprene and Ocimene-Emitting Transgenic Arabidopsis Plants under Contrasting Environmental Conditions. PLANTS (BASEL, SWITZERLAND) 2020; 9:E477. [PMID: 32283654 PMCID: PMC7238224 DOI: 10.3390/plants9040477] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Revised: 04/03/2020] [Accepted: 04/06/2020] [Indexed: 12/15/2022]
Abstract
Isoprenoids are among the most abundant biogenic volatile compounds (VOCs) emitted by plants, and mediate both biotic and abiotic stress responses. Here, we provide for the first time a comparative analysis of transgenic Arabidopsis lines constitutively emitting isoprene and ocimene. Transgenic lines and Columbia-0 (Col-0) Arabidopsis were characterized under optimal, water stress, and heat stress conditions. Under optimal conditions, the projected leaf area (PLA), relative growth rate, and final dry weight were generally higher in transgenics than Col-0. These traits were associated to a larger photosynthetic capacity and CO2 assimilation rate at saturating light. Isoprene and ocimene emitters displayed a moderately higher stress tolerance than Col-0, showing higher PLA and gas-exchange traits throughout the experiments. Contrasting behaviors were recorded for the two overexpressors under water stress, with isoprene emitters showing earlier stomatal closure (conservative behavior) than ocimene emitters (non-conservative behavior), which might suggest different induced strategies for water conservation and stress adaptation. Our work indicates that (i) isoprene and ocimene emitters resulted in enhanced PLA and biomass under optimal and control conditions and that (ii) a moderate stress tolerance is induced when isoprene and ocimene are constitutively emitted in Arabidopsis, thus providing evidence of their role as a potential preferable trait for crop improvement.
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Affiliation(s)
| | | | - Claudio Varotto
- Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, via Mach 1, 38010 San Michele all’Adige (TN), Italy; (M.F.); (M.L.)
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High productivity in hybrid-poplar plantations without isoprene emission to the atmosphere. Proc Natl Acad Sci U S A 2020; 117:1596-1605. [PMID: 31907313 DOI: 10.1073/pnas.1912327117] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Hybrid-poplar tree plantations provide a source for biofuel and biomass, but they also increase forest isoprene emissions. The consequences of increased isoprene emissions include higher rates of tropospheric ozone production, increases in the lifetime of methane, and increases in atmospheric aerosol production, all of which affect the global energy budget and/or lead to the degradation of air quality. Using RNA interference (RNAi) to suppress isoprene emission, we show that this trait, which is thought to be required for the tolerance of abiotic stress, is not required for high rates of photosynthesis and woody biomass production in the agroforest plantation environment, even in areas with high levels of climatic stress. Biomass production over 4 y in plantations in Arizona and Oregon was similar among genetic lines that emitted or did not emit significant amounts of isoprene. Lines that had substantially reduced isoprene emission rates also showed decreases in flavonol pigments, which reduce oxidative damage during extremes of abiotic stress, a pattern that would be expected to amplify metabolic dysfunction in the absence of isoprene production in stress-prone climate regimes. However, compensatory increases in the expression of other proteomic components, especially those associated with the production of protective compounds, such as carotenoids and terpenoids, and the fact that most biomass is produced prior to the hottest and driest part of the growing season explain the observed pattern of high biomass production with low isoprene emission. Our results show that it is possible to reduce the deleterious influences of isoprene on the atmosphere, while sustaining woody biomass production in temperate agroforest plantations.
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Werner C, Fasbender L, Romek KM, Yáñez-Serrano AM, Kreuzwieser J. Heat Waves Change Plant Carbon Allocation Among Primary and Secondary Metabolism Altering CO 2 Assimilation, Respiration, and VOC Emissions. FRONTIERS IN PLANT SCIENCE 2020; 11:1242. [PMID: 32922421 PMCID: PMC7456945 DOI: 10.3389/fpls.2020.01242] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2019] [Accepted: 07/29/2020] [Indexed: 05/17/2023]
Abstract
Processes controlling plant carbon allocation among primary and secondary metabolism, i.e., carbon assimilation, respiration, and VOC synthesis are still poorly constrained, particularly regarding their response to stress. To investigate these processes, we simulated a 10-day 38°C heat wave, analysing real-time carbon allocation into primary and secondary metabolism in the Mediterranean shrub Halimium halimifolium L. We traced position-specific 13C-labeled pyruvate into daytime VOC and CO2 emissions and during light-dark transition. Net CO2 assimilation strongly declined under heat, due to three-fold higher respiration rates. Interestingly, day respiration also increased two-fold. Decarboxylation of the C1-atom of pyruvate was the main process driving daytime CO2 release, whereas the C2-moiety was not decarboxylated in the TCA cycle. Heat induced high emissions of methanol, methyl acetate, acetaldehyde as well as mono- and sesquiterpenes, particularly during the first two days. After 10-days of heat a substantial proportion of 13C-labeled pyruvate was allocated into de novo synthesis of VOCs. Thus, during extreme heat waves high respiratory losses and reduced assimilation can shift plants into a negative carbon balance. Still, plants enhanced their investment into de novo VOC synthesis despite associated metabolic CO2 losses. We conclude that heat stress re-directed the proportional flux of key metabolites into pathways of VOC biosynthesis most likely at the expense of reactions of plant primary metabolism, which might highlight their importance for stress protection.
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Affiliation(s)
- Christiane Werner
- Ecosystem Physiology, University of Freiburg, Freiburg, Germany
- *Correspondence: Christiane Werner,
| | - Lukas Fasbender
- Ecosystem Physiology, University of Freiburg, Freiburg, Germany
| | | | - Ana Maria Yáñez-Serrano
- Ecosystem Physiology, University of Freiburg, Freiburg, Germany
- Center of Ecological Research and Forest Applications (CREAF), Universitat Autònoma de Barcelona, Barcelona, Spain
- Global Ecology Unit CREAF-CSIC-UAB, Cerdanyola del Vallès, Barcelona, Spain
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Yáñez-Serrano AM, Mahlau L, Fasbender L, Byron J, Williams J, Kreuzwieser J, Werner C. Heat stress increases the use of cytosolic pyruvate for isoprene biosynthesis. JOURNAL OF EXPERIMENTAL BOTANY 2019; 70:5827-5838. [PMID: 31396620 PMCID: PMC6812709 DOI: 10.1093/jxb/erz353] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Accepted: 07/18/2019] [Indexed: 05/28/2023]
Abstract
The increasing occurrence of heatwaves has intensified temperature stress on terrestrial vegetation. Here, we investigate how two contrasting isoprene-emitting tropical species, Ficus benjamina and Pachira aquatica, cope with heat stress and assess the role of internal plant carbon sources for isoprene biosynthesis in relation to thermotolerance. To our knowledge, this is the first study to report isoprene emissions from P. aquatica. We exposed plants to two levels of heat stress and determined the temperature response curves for isoprene and photosynthesis. To assess the use of internal C sources in isoprene biosynthesis, plants were fed with 13C position-labelled pyruvate. F. benjamina was more heat tolerant with higher constitutive isoprene emissions and stronger acclimation to higher temperatures than P. aquatica, which showed higher induced isoprene emissions at elevated temperatures. Under heat stress, both isoprene emissions and the proportion of cytosolic pyruvate allocated into isoprene synthesis increased. This represents a mechanism that P. aquatica, and to a lesser extent F. benjamina, has adopted as an immediate response to sudden increase in heat stress. However, in the long run under prolonged heat, the species with constitutive emissions (F. benjamina) was better adapted, indicating that plants that invest more carbon into protective emissions of biogenic volatile organic compounds tend to suffer less from heat stress.
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Affiliation(s)
| | - Lucas Mahlau
- Institute of Ecosystem Physiology, University Freiburg, Freiburg, Germany
| | - Lukas Fasbender
- Institute of Ecosystem Physiology, University Freiburg, Freiburg, Germany
| | - Joseph Byron
- Atmospheric Chemistry Department, Max-Planck Institute for Chemistry, Mainz, Germany
| | - Jonathan Williams
- Atmospheric Chemistry Department, Max-Planck Institute for Chemistry, Mainz, Germany
| | - Jürgen Kreuzwieser
- Institute of Ecosystem Physiology, University Freiburg, Freiburg, Germany
| | - Christiane Werner
- Institute of Ecosystem Physiology, University Freiburg, Freiburg, Germany
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Lantz AT, Allman J, Weraduwage SM, Sharkey TD. Isoprene: New insights into the control of emission and mediation of stress tolerance by gene expression. PLANT, CELL & ENVIRONMENT 2019; 42:2808-2826. [PMID: 31350912 PMCID: PMC6788959 DOI: 10.1111/pce.13629] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Revised: 07/19/2019] [Accepted: 07/21/2019] [Indexed: 05/10/2023]
Abstract
Isoprene is a volatile compound produced in large amounts by some, but not all, plants by the enzyme isoprene synthase. Plants emit vast quantities of isoprene, with a net global output of 600 Tg per year, and typical emission rates from individual plants around 2% of net carbon assimilation. There is significant debate about whether global climate change resulting from increasing CO2 in the atmosphere will increase or decrease global isoprene emission in the future. We show evidence supporting predictions of increased isoprene emission in the future, but the effects could vary depending on the environment under consideration. For many years, isoprene was believed to have immediate, physical effects on plants such as changing membrane properties or quenching reactive oxygen species. Although observations sometimes supported these hypotheses, the effects were not always observed, and the reasons for the variability were not apparent. Although there may be some physical effects, recent studies show that isoprene has significant effects on gene expression, the proteome, and the metabolome of both emitting and nonemitting species. Consistent results are seen across species and specific treatment protocols. This review summarizes recent findings on the role and control of isoprene emission from plants.
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Affiliation(s)
- Alexandra T. Lantz
- MSU-DOE Plant Research Laboratory, Department of Biochemistry and Molecular Biology, East Lansing, MI, United States
| | - Joshua Allman
- MSU-DOE Plant Research Laboratory, Department of Biochemistry and Molecular Biology, East Lansing, MI, United States
| | - Sarathi M. Weraduwage
- MSU-DOE Plant Research Laboratory, Department of Biochemistry and Molecular Biology, East Lansing, MI, United States
| | - Thomas D. Sharkey
- MSU-DOE Plant Research Laboratory, Department of Biochemistry and Molecular Biology, East Lansing, MI, United States
- Great Lakes Bioenergy Research Center, Madison, MI, United States
- Plant Resilience Institute, Michigan State University, East Lansing, MI, United States
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Reassimilation of Leaf Internal CO2 Contributes to Isoprene Emission in the Neotropical Species Inga edulis Mart. FORESTS 2019. [DOI: 10.3390/f10060472] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Isoprene (C5H8) is a hydrocarbon gas emitted by many tree species and has been shown to protect photosynthesis under abiotic stress. Under optimal conditions for photosynthesis, ~70%–90% of carbon used for isoprene biosynthesis is produced from recently assimilated atmospheric CO2. While the contribution of alternative carbon sources that increase with leaf temperature and other stresses have been demonstrated, uncertainties remain regarding the biochemical source(s) of isoprene carbon. In this study, we investigated leaf isoprene emissions (Is) from neotropical species Inga edulis Mart. as a function of light and temperature under ambient (450 µmol m−2 s−1) and CO2-free (0 µmol m−2 s−1) atmosphere. Is under CO2-free atmosphere showed light-dependent emission patterns similar to those observed under ambient CO2, but with lower light saturation point. Leaves treated with the photosynthesis inhibitor DCMU (3-(3,4-dichlorophenyl)-1,1-dimethylurea) failed to produce detectable Is in normal light under a CO2-free atmosphere. While strong temperature-dependent Is were observed under CO2-free atmosphere in the light, dark conditions failed to produce detectable Is even at the highest temperatures studied (40 °C). Treatment of leaves with 13C-labeled sodium bicarbonate under CO2-free atmosphere resulted in Is with over 50% containing at least one 13C atom. Is under CO2-free atmosphere and standard conditions of light and leaf temperature represented 19% ± 7% of emissions under ambient CO2. The results show that the reassimilation of leaf internal CO2 contributes to Is in the neotropical species I. edulis. Through the consumption of excess photosynthetic energy, our results support a role of isoprene biosynthesis, together with photorespiration, as a key tolerance mechanism against high temperature and high light in the tropics.
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Sharkey TD, Monson RK. Isoprene research - 60 years later, the biology is still enigmatic. PLANT, CELL & ENVIRONMENT 2017; 40:1671-1678. [PMID: 28160522 DOI: 10.1111/pce.12930] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Revised: 01/28/2017] [Accepted: 01/30/2017] [Indexed: 05/26/2023]
Abstract
Isoprene emission is a major component of biosphere-atmosphere interactions. It is the single largest source of non-methane hydrocarbon in the atmosphere. The first report of isoprene emission from plants was published in 1957 by Professor Guivi Sanadze. While humans have smelled the monoterpene hydrocarbons made by coniferous trees since their earliest migrations, only in 1957 did the world became aware that other trees make a type of hydrocarbon in even greater amounts but one to which the human nose is much less sensitive. For this 60th anniversary of the first report of isoprene emission from leaves, we trace the discovery and development of the research field, highlighting some of the most seminal observations and theoretical interpretations. This is not an exhaustive review, and many important papers are not cited, but we hope it will be of general interest to read how research in this field developed, how new observations forced us to reevaluate our theories about the significance of isoprene biosynthesis to plant physiology and adaptation and how scientific serendipity can sometimes drive a topic forward.
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Affiliation(s)
- Thomas D Sharkey
- Department of Biochemistry and Molecular Biology and Plant Resilience Institute, Michigan State University, East Lansing, MI, 48824, USA
| | - Russell K Monson
- School of Natural Resources and the Environment and Laboratory of Tree Ring Research, University of Arizona, Tucson, AZ, 85721, USA
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Fini A, Brunetti C, Loreto F, Centritto M, Ferrini F, Tattini M. Isoprene Responses and Functions in Plants Challenged by Environmental Pressures Associated to Climate Change. FRONTIERS IN PLANT SCIENCE 2017; 8:1281. [PMID: 28798754 PMCID: PMC5526906 DOI: 10.3389/fpls.2017.01281] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Accepted: 07/06/2017] [Indexed: 05/12/2023]
Abstract
The functional reasons for isoprene emission are still a matter of hot debate. It was hypothesized that isoprene biosynthesis evolved as an ancestral mechanism in plants adapted to high water availability, to cope with transient and recurrent oxidative stresses during their water-to-land transition. There is a tight association between isoprene emission and species hygrophily, suggesting that isoprene emission may be a favorable trait to cope with occasional exposure to stresses in mesic environments. The suite of morpho-anatomical traits does not allow a conservative water use in hygrophilic mesophytes challenged by the environmental pressures imposed or exacerbated by drought and heat stress. There is evidence that in stressed plants the biosynthesis of isoprene is uncoupled from photosynthesis. Because the biosynthesis of isoprene is costly, the great investment of carbon and energy into isoprene must have relevant functional reasons. Isoprene is effective in preserving the integrity of thylakoid membranes, not only through direct interaction with their lipid acyl chains, but also by up-regulating proteins associated with photosynthetic complexes and enhancing the biosynthesis of relevant membrane components, such as mono- and di-galactosyl-diacyl glycerols and unsaturated fatty acids. Isoprene may additionally protect photosynthetic membranes by scavenging reactive oxygen species. Here we explore the mode of actions and the potential significance of isoprene in the response of hygrophilic plants when challenged by severe stress conditions associated to rapid climate change in temperate climates, with special emphasis to the concomitant effect of drought and heat. We suggest that isoprene emission may be not a good estimate for its biosynthesis and concentration in severely droughted leaves, being the internal concentration of isoprene the important trait for stress protection.
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Affiliation(s)
- Alessio Fini
- Department of Agricultural and Environmental Sciences – Production, Landscape, Agroenergy, University of MilanMilan, Italy
| | - Cecilia Brunetti
- Department of Biology, Agriculture and Food Science, National Research Council of Italy, Trees and Timber InstituteSesto Fiorentino, Italy
- Department of Agrifood Production and Environmental Sciences, University of FlorenceFlorence, Italy
| | - Francesco Loreto
- Department of Biology, Agriculture and Food Science, National Research Council of ItalyRome, Italy
| | - Mauro Centritto
- Department of Biology, Agriculture and Food Science, National Research Council of Italy, Trees and Timber InstituteSesto Fiorentino, Italy
| | - Francesco Ferrini
- Department of Agrifood Production and Environmental Sciences, University of FlorenceFlorence, Italy
| | - Massimiliano Tattini
- Department of Biology, Agriculture and Food Science, National Research Council of Italy, Institute for Sustainable Plant ProtectionSesto Fiorentino, Italy
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Harvey CM, Sharkey TD. Exogenous isoprene modulates gene expression in unstressed Arabidopsis thaliana plants. PLANT, CELL & ENVIRONMENT 2016; 39:1251-1263. [PMID: 26477606 DOI: 10.1111/pce.12660] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Revised: 09/30/2015] [Accepted: 10/07/2015] [Indexed: 06/05/2023]
Abstract
Isoprene is a well-studied volatile hemiterpene that protects plants from abiotic stress through mechanisms that are not fully understood. The antioxidant and membrane stabilizing potential of isoprene are the two most commonly invoked mechanisms. However, isoprene also affects phenylpropanoid metabolism, suggesting an additional role as a signalling molecule. In this study, microarray-based gene expression profiling reveals transcriptional reprogramming of Arabidopsis thaliana plants fumigated for 24 h with a physiologically relevant concentration of isoprene. Functional enrichment analysis of fumigated plants revealed enhanced heat- and light-stress-responsive processes in response to isoprene. Isoprene induced a network enriched in ERF and WRKY transcription factors, which may play a role in stress tolerance. The isoprene-induced up-regulation of phenylpropanoid biosynthetic genes was specifically confirmed using quantitative reverse transcription polymerase chain reaction. These results support a role for isoprene as a signalling molecule, in addition to its possible roles as an antioxidant and membrane thermoprotectant.
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Affiliation(s)
- Christopher M Harvey
- Department of Biochemistry and Molecular Biology, Michigan State University, 603 Wilson Rd., East Lansing, MI, 48824, USA
| | - Thomas D Sharkey
- Department of Biochemistry and Molecular Biology, Michigan State University, 603 Wilson Rd., East Lansing, MI, 48824, USA
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Tiwari S, Grote R, Churkina G, Butler T. Ozone damage, detoxification and the role of isoprenoids - new impetus for integrated models. FUNCTIONAL PLANT BIOLOGY : FPB 2016; 43:324-336. [PMID: 32480464 DOI: 10.1071/fp15302] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2015] [Accepted: 12/22/2015] [Indexed: 06/11/2023]
Abstract
High concentrations of ozone (O3) can have significant impacts on the health and productivity of agricultural and forest ecosystems, leading to significant economic losses. In order to estimate this impact under a wide range of environmental conditions, the mechanisms of O3 impacts on physiological and biochemical processes have been intensively investigated. This includes the impact on stomatal conductance, the formation of reactive oxygen species and their effects on enzymes and membranes, as well as several induced and constitutive defence responses. This review summarises these processes, discusses their importance for O3 damage scenarios and assesses to which degree this knowledge is currently used in ecosystem models which are applied for impact analyses. We found that even in highly sophisticated models, feedbacks affecting regulation, detoxification capacity and vulnerability are generally not considered. This implies that O3 inflicted alterations in carbon and water balances cannot be sufficiently well described to cover immediate plant responses under changing environmental conditions. Therefore, we suggest conceptual models that link the depicted feedbacks to available process-based descriptions of stomatal conductance, photosynthesis and isoprenoid formation, particularly the linkage to isoprenoid models opens up new options for describing biosphere-atmosphere interactions.
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Affiliation(s)
- Supriya Tiwari
- Department of Botany, Institute of Science, Banaras Hindu University, Varanasi-221005, India
| | - Rüdiger Grote
- Karlsruhe Institute of Technology, Institute of Meteorology and Climate Research, Kreuzeckbahnstr. 19, 82467 Garmisch-Partenkirchen, Germany
| | - Galina Churkina
- Institute of Advanced Sustainable Studies, Berliner St. 130, 14467 Potsdam, Germany
| | - Tim Butler
- Institute of Advanced Sustainable Studies, Berliner St. 130, 14467 Potsdam, Germany
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