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Charuvi D, Nevo R, Shimoni E, Naveh L, Zia A, Adam Z, Farrant JM, Kirchhoff H, Reich Z. Photoprotection conferred by changes in photosynthetic protein levels and organization during dehydration of a homoiochlorophyllous resurrection plant. PLANT PHYSIOLOGY 2015; 167:1554-65. [PMID: 25713340 PMCID: PMC4378169 DOI: 10.1104/pp.114.255794] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Accepted: 02/20/2015] [Indexed: 05/18/2023]
Abstract
During desiccation, homoiochlorophyllous resurrection plants retain most of their photosynthetic apparatus, allowing them to resume photosynthetic activity quickly upon water availability. These plants rely on various mechanisms to prevent the formation of reactive oxygen species and/or protect their tissues from the damage they inflict. In this work, we addressed the issue of how homoiochlorophyllous resurrection plants deal with the problem of excessive excitation/electron pressures during dehydration using Craterostigma pumilum as a model plant. To investigate the alterations in the supramolecular organization of photosynthetic protein complexes, we examined cryoimmobilized, freeze-fractured leaf tissues using (cryo)scanning electron microscopy. These examinations revealed rearrangements of photosystem II (PSII) complexes, including a lowered density during moderate dehydration, consistent with a lower level of PSII proteins, as shown by biochemical analyses. The latter also showed a considerable decrease in the level of cytochrome f early during dehydration, suggesting that initial regulation of the inhibition of electron transport is achieved via the cytochrome b6f complex. Upon further dehydration, PSII complexes are observed to arrange into rows and semicrystalline arrays, which correlates with the significant accumulation of sucrose and the appearance of inverted hexagonal lipid phases within the membranes. As opposed to PSII and cytochrome f, the light-harvesting antenna complexes of PSII remain stable throughout the course of dehydration. Altogether, these results, along with photosynthetic activity measurements, suggest that the protection of retained photosynthetic components is achieved, at least in part, via the structural rearrangements of PSII and (likely) light-harvesting antenna complexes into a photochemically quenched state.
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Affiliation(s)
- Dana Charuvi
- Department of Biological Chemistry (D.C., R.N., Z.R.) and Electron Microscopy Unit (E.S.), Weizmann Institute of Science, Rehovot 76100, Israel;Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, Hebrew University of Jerusalem, Rehovot 76100, Israel (L.N., Z.A.);Institute of Biological Chemistry, Washington State University, Pullman, Washington 99164-6340 (A.Z., H.K.); andDepartment of Molecular and Cell Biology, University of Cape Town, Rondebosch 7701, South Africa (J.M.F.)
| | - Reinat Nevo
- Department of Biological Chemistry (D.C., R.N., Z.R.) and Electron Microscopy Unit (E.S.), Weizmann Institute of Science, Rehovot 76100, Israel;Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, Hebrew University of Jerusalem, Rehovot 76100, Israel (L.N., Z.A.);Institute of Biological Chemistry, Washington State University, Pullman, Washington 99164-6340 (A.Z., H.K.); andDepartment of Molecular and Cell Biology, University of Cape Town, Rondebosch 7701, South Africa (J.M.F.)
| | - Eyal Shimoni
- Department of Biological Chemistry (D.C., R.N., Z.R.) and Electron Microscopy Unit (E.S.), Weizmann Institute of Science, Rehovot 76100, Israel;Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, Hebrew University of Jerusalem, Rehovot 76100, Israel (L.N., Z.A.);Institute of Biological Chemistry, Washington State University, Pullman, Washington 99164-6340 (A.Z., H.K.); andDepartment of Molecular and Cell Biology, University of Cape Town, Rondebosch 7701, South Africa (J.M.F.)
| | - Leah Naveh
- Department of Biological Chemistry (D.C., R.N., Z.R.) and Electron Microscopy Unit (E.S.), Weizmann Institute of Science, Rehovot 76100, Israel;Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, Hebrew University of Jerusalem, Rehovot 76100, Israel (L.N., Z.A.);Institute of Biological Chemistry, Washington State University, Pullman, Washington 99164-6340 (A.Z., H.K.); andDepartment of Molecular and Cell Biology, University of Cape Town, Rondebosch 7701, South Africa (J.M.F.)
| | - Ahmad Zia
- Department of Biological Chemistry (D.C., R.N., Z.R.) and Electron Microscopy Unit (E.S.), Weizmann Institute of Science, Rehovot 76100, Israel;Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, Hebrew University of Jerusalem, Rehovot 76100, Israel (L.N., Z.A.);Institute of Biological Chemistry, Washington State University, Pullman, Washington 99164-6340 (A.Z., H.K.); andDepartment of Molecular and Cell Biology, University of Cape Town, Rondebosch 7701, South Africa (J.M.F.)
| | - Zach Adam
- Department of Biological Chemistry (D.C., R.N., Z.R.) and Electron Microscopy Unit (E.S.), Weizmann Institute of Science, Rehovot 76100, Israel;Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, Hebrew University of Jerusalem, Rehovot 76100, Israel (L.N., Z.A.);Institute of Biological Chemistry, Washington State University, Pullman, Washington 99164-6340 (A.Z., H.K.); andDepartment of Molecular and Cell Biology, University of Cape Town, Rondebosch 7701, South Africa (J.M.F.)
| | - Jill M Farrant
- Department of Biological Chemistry (D.C., R.N., Z.R.) and Electron Microscopy Unit (E.S.), Weizmann Institute of Science, Rehovot 76100, Israel;Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, Hebrew University of Jerusalem, Rehovot 76100, Israel (L.N., Z.A.);Institute of Biological Chemistry, Washington State University, Pullman, Washington 99164-6340 (A.Z., H.K.); andDepartment of Molecular and Cell Biology, University of Cape Town, Rondebosch 7701, South Africa (J.M.F.)
| | - Helmut Kirchhoff
- Department of Biological Chemistry (D.C., R.N., Z.R.) and Electron Microscopy Unit (E.S.), Weizmann Institute of Science, Rehovot 76100, Israel;Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, Hebrew University of Jerusalem, Rehovot 76100, Israel (L.N., Z.A.);Institute of Biological Chemistry, Washington State University, Pullman, Washington 99164-6340 (A.Z., H.K.); andDepartment of Molecular and Cell Biology, University of Cape Town, Rondebosch 7701, South Africa (J.M.F.)
| | - Ziv Reich
- Department of Biological Chemistry (D.C., R.N., Z.R.) and Electron Microscopy Unit (E.S.), Weizmann Institute of Science, Rehovot 76100, Israel;Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, Hebrew University of Jerusalem, Rehovot 76100, Israel (L.N., Z.A.);Institute of Biological Chemistry, Washington State University, Pullman, Washington 99164-6340 (A.Z., H.K.); andDepartment of Molecular and Cell Biology, University of Cape Town, Rondebosch 7701, South Africa (J.M.F.)
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Bonneau L, Gerbeau-Pissot P, Thomas D, Der C, Lherminier J, Bourque S, Roche Y, Simon-Plas F. Plasma membrane sterol complexation, generated by filipin, triggers signaling responses in tobacco cells. BIOCHIMICA ET BIOPHYSICA ACTA 2010; 1798:2150-9. [PMID: 20674542 DOI: 10.1016/j.bbamem.2010.07.026] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2010] [Revised: 07/12/2010] [Accepted: 07/23/2010] [Indexed: 12/31/2022]
Abstract
The effects of changes in plasma membrane (PM) sterol lateral organization and availability on the control of signaling pathways have been reported in various animal systems, but rarely assessed in plant cells. In the present study, the pentaene macrolide antibiotic filipin III, commonly used in animal systems as a sterol sequestrating agent, was applied to tobacco cells. We show that filipin can be used at a non-lethal concentration that still allows an homogeneous labeling of the plasma membrane and the formation of filipin-sterol complexes at the ultrastructural level. This filipin concentration triggers a rapid and transient NADPH oxidase-dependent production of reactive oxygen species, together with an increase in both medium alkalinization and conductivity. Pharmacological inhibition studies suggest that these signaling events may be regulated by phosphorylations and free calcium. By conducting FRAP experiments using the di-4-ANEPPDHQ probe and spectrofluorimetry using the Laurdan probe, we provide evidence for a filipin-induced increase in PM viscosity that is also regulated by phosphorylations. We conclude that filipin triggers ligand-independent signaling responses in plant cells. The present findings strongly suggest that changes in PM sterol availability could act as a sensor of the modifications of cell environment in plants leading to adaptive cell responses through regulated signaling processes.
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