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The role of lipid metabolism in the acquisition of desiccation tolerance in Craterostigma plantagineum: a comparative approach 总被引:1,自引:0,他引:1
Francisco Gasulla Katharina vom Dorp Isabel Dombrink Ulrich Zähringer Nicolas Gisch Peter Dörmann Dorothea Bartels 《The Plant journal : for cell and molecular biology》2013,75(5):726-741
Dehydration leads to different physiological and biochemical responses in plants. We analysed the lipid composition and the expression of genes involved in lipid biosynthesis in the desiccation‐tolerant plant Craterostigma plantagineum. A comparative approach was carried out with Lindernia brevidens (desiccation tolerant) and two desiccation‐sensitive species, Lindernia subracemosa and Arabidopsis thaliana. In C. plantagineum the total lipid content remained constant while the lipid composition underwent major changes during desiccation. The most prominent change was the removal of monogalactosyldiacylglycerol (MGDG) from the thylakoids. Analysis of molecular species composition revealed that around 50% of 36:x (number of carbons in the acyl chains: number of double bonds) MGDG was hydrolysed and diacylglycerol (DAG) used for phospholipid synthesis, while another MGDG fraction was converted into digalactosyldiacylglycerol via the DGD1/DGD2 pathway and subsequently into oligogalactolipids by SFR2. 36:x‐DAG was also employed for the synthesis of triacylglycerol. Phosphatidic acid (PA) increased in C. plantagineum, L. brevidens, and L. subracemosa, in agreement with a role of PA as an intermediate of lipid turnover and of phospholipase D in signalling during desiccation. 34:x‐DAG, presumably derived from de novo assembly, was converted into phosphatidylinositol (PI) in C. plantagineum and L. brevidens, but not in desiccation‐sensitive plants, suggesting that PI is involved in acquisition of desiccation tolerance. The accumulation of oligogalactolipids and PI in the chloroplast and extraplastidial membranes, respectively, increases the concentration of hydroxyl groups and enhances the ratio of bilayer‐ to non‐bilayer‐forming lipids, thus contributing to protein and membrane stabilization. 相似文献
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Hilbricht T Salamini F Bartels D 《The Plant journal : for cell and molecular biology》2002,31(3):293-303
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In order to understand the molecular mechanisms which are responsible for desiccation tolerance in the resurrection plant
Craterostigma plantagineum Hochst. a thorough analysis of the CDeT11-24 gene family was performed. CDeT11-24 comprises a small gene family whose genes
are expressed in response to dehydration, salt stress and abscisic acid (ABA) treatment in leaves. The gene products are constitutively
expressed in roots and disappear only when the plants are transferred to water. It is therefore suggested that the proteins
are involved in sensing water status. The predicted proteins are very hydrophilic; they share some features with late-embryogenesis-abundant
proteins, and sequence similarities were found with two ABA- and drought-regulated Arabidopsis genes. The analysis of β-glucuronidase reporter genes driven by the CDeT11-24 promoter showed high activity in mature seeds
in both transgenic Arabidopsis and tobacco. In vegetative tissues the promoter activity in response to ABA was restricted to young Arabidosis seedlings. The responsiveness to ABA during later developmental stages was regained in the presence of the Arabidopsis gene product ABI3. Dehydration-induced promoter activity was only observed in Arabidopsis leaves at a particular developmental stage. This analysis indicates that some components in the signal transduction pathway
of the resurrection plant are not active in tobacco or Arabidopsis.
Received: 26 April 1997 / Accepted: 16 July 1997 相似文献
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An investigation into the role of light during desiccation of three angiosperm resurrection plants 总被引:8,自引:1,他引:7
J. M. FARRANT C. VANDER WILLIGEN D. A. LOFFELL S. BARTSCH & A. WHITTAKER 《Plant, cell & environment》2003,26(8):1275-1286
Under water‐limiting conditions excitation energy harnessed by chlorophyll can lead to the formation of reactive oxygen species (ROS). Resurrection plants minimize their formation by preventing the opportunity for light–chlorophyll interaction but also quench them via antioxidants. Poikilochlorohyllous species such as Xerophyta humilis break down chlorophyll to avoid ROS formation. Homoiochlorophyllous types retain chlorophyll. We proposed that leaf folding during drying of Craterostigma wilmsii and Myrothamnus flabellifolius shades chlorophyll to avoid ROS (Farrant, Plant Ecology 151, 29–39, 2000). This was tested by preventing leaf folding during drying in light. As controls, plants were dried without light, and X. humilis was included. Craterostigma wilmsii did not survive drying in light if the leaves were prevented from folding, despite protection from increased anthocyanin and sucrose and elevated antioxidant enzyme activity. Membranes were damaged, electrolyte leakage was elevated and plastoglobuli (evidence of light stress) accumulated in chloroplasts. Restrained leaves of M. flabellifolius survived drying in light. Leaf folding allows less shading, but the extent of chemical protection (anthocyanin content and antioxidant activity) is considerably higher in this species compared with C. wilmsii. Chemical protection appears to be light regulated in M. flabellifolius but not in C. wilmsii. Drying in the dark resulted in loss of viability in the homoiochlorophyllous but not the poikilochlorophyllous species. It is hypothesized that some of the genes required for protection are light regulated in the former. 相似文献
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Insights into the cellular mechanisms of desiccation tolerance among angiosperm resurrection plant species 总被引:3,自引:0,他引:3
Water is a major limiting factor in growth and reproduction in plants. The ability of tissues to survive desiccation is commonly found in seeds or pollen but rarely present in vegetative tissues. Resurrection plants are remarkable as they can tolerate almost complete water loss from their vegetative tissues such as leaves and roots. Metabolism is shut down as they dehydrate and the plants become apparently lifeless. Upon rehydration these plants recover full metabolic competence and ‘resurrect’. In order to cope with desiccation, resurrection plants have to overcome a number of stresses as water is lost from the cells, among them oxidative stress, destabilization or loss of membrane integrity and mechanical stress. This review will mainly focus on the effect of dehydration in angiosperm resurrection plants and some of the strategies developed by these plants to tolerate desiccation. Resurrection plants are important experimental models and understanding the physiological and molecular aspects of their desiccation tolerance is of great interest for developing drought‐tolerant crop species adapted to semi‐arid areas. 相似文献
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Retrotransposons and siRNA have a role in the evolution of desiccation tolerance leading to resurrection of the plant Craterostigma plantagineum 总被引:1,自引:1,他引:0
Hilbricht T Varotto S Sgaramella V Bartels D Salamini F Furini A 《The New phytologist》2008,179(3):877-887
* Craterostigma plantagineum can lose up to 96% of its water content but fully recover within hours after rehydration. The callus tissue of the plant becomes desiccation tolerant upon pre-incubation with abscisic acid (ABA). In callus and vegetative organs, ABA addition and water depletion induce a set of dehydration-responsive genes. * Previously, activation tagging led to the isolation of Craterostigma desiccation tolerant (CDT-1), a dehydration-related ABA-inducible gene which renders callus desiccation tolerant without ABA pre-treatment. This gene belongs to a family of retroelements, members of which are inducible by dehydration. * Craterostigma plantagineum transformation with mutated versions of CDT-1 indicated that protein is not required for the induction of callus desiccation tolerance. Northern analysis and protoplast transfection indicated that CDT-1 directs the synthesis of a double-stranded 21-bp short interfering RNA (siRNA), which opens the metabolic pathway for desiccation tolerance. * Via transposition, these retroelements have progressively increased the capacity of the species to synthesize siRNA and thus recover after dehydration. This may be a case of evolution towards the acquisition of a new trait, stimulated by the environment acting directly on intra-genomic DNA replication. 相似文献