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In vivo spectroscopy and NMR metabolite fingerprinting approaches to connect the dynamics of photosynthetic and metabolic phenotypes in resurrection plant Haberlea rhodopensis during desiccation and recovery.

Mladenov P, Finazzi G, Bligny R, Moyankova D, Zasheva D, Boisson AM, Brugière S, Krasteva V, Alipieva K, Simova S, Tchorbadjieva M, Goltsev V, Ferro M, Rolland N, Djilianov D - Front Plant Sci (2015)

Bottom Line: The NMR fingerprint shows the significant metabolic changes in several pathways.We found a decline of valine accompanied by lipid degradation during stress, likely to provide alternative carbon sources for sucrose accumulation at late stages of desiccation.This accumulation, as well as the increased levels of glycerophosphodiesters during drought stress could provide osmoprotection to the cells.

View Article: PubMed Central - PubMed

Affiliation: Abiotic Stress Group, Agrobioinstitute, Agricultural Academy Sofia, Bulgaria.

ABSTRACT
The resurrection plant Haberlea rhodopensis was used to study dynamics of drought response of photosynthetic machinery parallel with changes in primary metabolism. A relation between leaf water content and photosynthetic performance was established, enabling us to perform a non-destructive evaluation of the plant water status during stress. Spectroscopic analysis of photosynthesis indicated that, at variance with linear electron flow (LEF) involving photosystem (PS) I and II, cyclic electron flow around PSI remains active till almost full dry state at the expense of the LEF, due to the changed protein organization of photosynthetic apparatus. We suggest that, this activity could have a photoprotective role and prevent a complete drop in adenosine triphosphate (ATP), in the absence of LEF, to fuel specific energy-dependent processes necessary for the survival of the plant, during the late states of desiccation. The NMR fingerprint shows the significant metabolic changes in several pathways. Due to the declining of LEF accompanied by biosynthetic reactions during desiccation, a reduction of the ATP pool during drought was observed, which was fully and quickly recovered after plants rehydration. We found a decline of valine accompanied by lipid degradation during stress, likely to provide alternative carbon sources for sucrose accumulation at late stages of desiccation. This accumulation, as well as the increased levels of glycerophosphodiesters during drought stress could provide osmoprotection to the cells.

No MeSH data available.


Related in: MedlinePlus

Photosynthetic performance and organization of photosynthetic apparatus of H. rhodopensis during selected states of desiccation and recovery. (A) Representative averaged OJIP curves and water content (WC), respectively, from different samples classified with SOM, corresponding to different stress states of plants. State C: watered plants (80%), state D1: moderate desiccation (60%), state D2: severe desiccation (38%), state D3: dry plants (16%), state R1: intermediate recovery (73%), state R2: full recovery (81%). The SD was calculated from 9 to 12 measurements, respectively. (B) Quantification of Fv/Fm, linear and Cyclic electron flow at selected states of desiccation and recovery. The signal abundance is normalized to control state. The SD was calculated from 6 measurements, respectively. (C) BN-PAGE separation of thylakoid protein complexes at selected states of desiccation and recovery after solubilization with n-dodecyl-β-D-maltoside (DDM). (D) Densitometry quantification of the resolved photosynthetic complexes normalized to control levels. The SD was calculated from three independent gels.
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Figure 2: Photosynthetic performance and organization of photosynthetic apparatus of H. rhodopensis during selected states of desiccation and recovery. (A) Representative averaged OJIP curves and water content (WC), respectively, from different samples classified with SOM, corresponding to different stress states of plants. State C: watered plants (80%), state D1: moderate desiccation (60%), state D2: severe desiccation (38%), state D3: dry plants (16%), state R1: intermediate recovery (73%), state R2: full recovery (81%). The SD was calculated from 9 to 12 measurements, respectively. (B) Quantification of Fv/Fm, linear and Cyclic electron flow at selected states of desiccation and recovery. The signal abundance is normalized to control state. The SD was calculated from 6 measurements, respectively. (C) BN-PAGE separation of thylakoid protein complexes at selected states of desiccation and recovery after solubilization with n-dodecyl-β-D-maltoside (DDM). (D) Densitometry quantification of the resolved photosynthetic complexes normalized to control levels. The SD was calculated from three independent gels.

Mentions: The OJIP parts of the PF transients depicted all parameters exhibit pronounced decrease reflected by the decreasing of P-level (FP), during drought stress, followed by the reversible increasing during recovery (Figure 2A). The calculated quantum yields and performance indexes (Supplementary Table S2), derived from the averaged OJIP curves (Figure 2A) show that the maximum quantum yield for primary photochemistry (phi Po), do not change significantly during C–D1 state transition, followed by a moderate decrease during D1–D2 transition, and a more drastic change during D2–D3 transition. On the other hand, we observed a pronounced decrease of the quantum yield for electron transport beyond QA (phi Eo) and quantum yield for reduction of end electron acceptors at the PSI acceptor side (φRo), which clearly coincided with the decrease of leaf WC (Supplementary Table S2). The absorption by PSII antenna pigments (ABS/RC), trapping energy (TRo/RC, ETo/RC) and the electron transport per fully active PS II reaction center increased during drought (Supplementary Table S2), indicating an inactivation of the PSII reaction centers. Indeed, we showed that the efficiency of PSII during water stress corroborates previous studies on the inhibition of CO2 fixation (Georgieva et al., 2007) in parallel with the WC. It appears that the well-established relationship between the PSII activity and CO2 assimilation (Genty et al., 1989) is still present during water deprivation in H. rhodopensis. We evaluated LEF from fluorescence-derived analysis, of plants in light-adapted state (Figure 2B) as commonly done in several publications for resurrection plants (Georgieva et al., 2007, 2010; Ingle et al., 2008; Beckett et al., 2012). CEF was estimated by changes in the redox state of P700 upon illumination with far red light of previously dark-adapted material (Figure 2B). By assessing the initial rate of P700 oxidation in far red during the different steps of water deprivation and rehydration (Supplementary Figure S2), we were able to quantify the CEF: LEF ratio and to compare it with changes in linear flow (from the ΦPSII) and in the PSII efficiency, here evinced from the Fv/Fm parameter We found that during the selected states of stress, the maximum quantum yield for primary photochemistry (Fv/Fm), and LEF decreased in an identical way as the measured quantum yields derived from OJIP curves. A smaller decrease was found in the CEF efficiency, suggesting that this process was more resistant to the applied water stress (Figure 2B). Our results from BN-PAGE showed bands representing the typical organization of the photosynthetic apparatus in plants: PSII dimer (PSII [2]); PSII monomer (PSII [1]); cytochrome b6f complex (Cytb6f); light-harvesting complex II (LHCII) assemblies; LHCII, as well as high molecular weight supercomplexes consisting of different forms of PSII (LHCIIsc), (Figure 2C). During the transition from C–D1 state, the higher molecular weight complexes were disassembled and the bands corresponding to PSII-LHCIIsc were reduced (Figure 2D). This decrease of PSII-LHCIIsc continued up to the D3 state. At full dry state all supercomplexes were disassembled and the abundance of PSII dimers also declined. In addition decline of cytochrome b6f complex content in thylakoids has been observed during D2–D3 state transition. During rewatering, the supercomplexes were partially recovered at R1 state and fully recovered at R2 state. These observations might suggest a relation between changes in the relative abundance/functional assembly of PSII and the main electron transport carrier-cytochrome b6f complex (Figure 2D) and the relative contribution of PSII-driven LEF and PSI -driven electron flow during desiccation (Figure 2B).


In vivo spectroscopy and NMR metabolite fingerprinting approaches to connect the dynamics of photosynthetic and metabolic phenotypes in resurrection plant Haberlea rhodopensis during desiccation and recovery.

Mladenov P, Finazzi G, Bligny R, Moyankova D, Zasheva D, Boisson AM, Brugière S, Krasteva V, Alipieva K, Simova S, Tchorbadjieva M, Goltsev V, Ferro M, Rolland N, Djilianov D - Front Plant Sci (2015)

Photosynthetic performance and organization of photosynthetic apparatus of H. rhodopensis during selected states of desiccation and recovery. (A) Representative averaged OJIP curves and water content (WC), respectively, from different samples classified with SOM, corresponding to different stress states of plants. State C: watered plants (80%), state D1: moderate desiccation (60%), state D2: severe desiccation (38%), state D3: dry plants (16%), state R1: intermediate recovery (73%), state R2: full recovery (81%). The SD was calculated from 9 to 12 measurements, respectively. (B) Quantification of Fv/Fm, linear and Cyclic electron flow at selected states of desiccation and recovery. The signal abundance is normalized to control state. The SD was calculated from 6 measurements, respectively. (C) BN-PAGE separation of thylakoid protein complexes at selected states of desiccation and recovery after solubilization with n-dodecyl-β-D-maltoside (DDM). (D) Densitometry quantification of the resolved photosynthetic complexes normalized to control levels. The SD was calculated from three independent gels.
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Figure 2: Photosynthetic performance and organization of photosynthetic apparatus of H. rhodopensis during selected states of desiccation and recovery. (A) Representative averaged OJIP curves and water content (WC), respectively, from different samples classified with SOM, corresponding to different stress states of plants. State C: watered plants (80%), state D1: moderate desiccation (60%), state D2: severe desiccation (38%), state D3: dry plants (16%), state R1: intermediate recovery (73%), state R2: full recovery (81%). The SD was calculated from 9 to 12 measurements, respectively. (B) Quantification of Fv/Fm, linear and Cyclic electron flow at selected states of desiccation and recovery. The signal abundance is normalized to control state. The SD was calculated from 6 measurements, respectively. (C) BN-PAGE separation of thylakoid protein complexes at selected states of desiccation and recovery after solubilization with n-dodecyl-β-D-maltoside (DDM). (D) Densitometry quantification of the resolved photosynthetic complexes normalized to control levels. The SD was calculated from three independent gels.
Mentions: The OJIP parts of the PF transients depicted all parameters exhibit pronounced decrease reflected by the decreasing of P-level (FP), during drought stress, followed by the reversible increasing during recovery (Figure 2A). The calculated quantum yields and performance indexes (Supplementary Table S2), derived from the averaged OJIP curves (Figure 2A) show that the maximum quantum yield for primary photochemistry (phi Po), do not change significantly during C–D1 state transition, followed by a moderate decrease during D1–D2 transition, and a more drastic change during D2–D3 transition. On the other hand, we observed a pronounced decrease of the quantum yield for electron transport beyond QA (phi Eo) and quantum yield for reduction of end electron acceptors at the PSI acceptor side (φRo), which clearly coincided with the decrease of leaf WC (Supplementary Table S2). The absorption by PSII antenna pigments (ABS/RC), trapping energy (TRo/RC, ETo/RC) and the electron transport per fully active PS II reaction center increased during drought (Supplementary Table S2), indicating an inactivation of the PSII reaction centers. Indeed, we showed that the efficiency of PSII during water stress corroborates previous studies on the inhibition of CO2 fixation (Georgieva et al., 2007) in parallel with the WC. It appears that the well-established relationship between the PSII activity and CO2 assimilation (Genty et al., 1989) is still present during water deprivation in H. rhodopensis. We evaluated LEF from fluorescence-derived analysis, of plants in light-adapted state (Figure 2B) as commonly done in several publications for resurrection plants (Georgieva et al., 2007, 2010; Ingle et al., 2008; Beckett et al., 2012). CEF was estimated by changes in the redox state of P700 upon illumination with far red light of previously dark-adapted material (Figure 2B). By assessing the initial rate of P700 oxidation in far red during the different steps of water deprivation and rehydration (Supplementary Figure S2), we were able to quantify the CEF: LEF ratio and to compare it with changes in linear flow (from the ΦPSII) and in the PSII efficiency, here evinced from the Fv/Fm parameter We found that during the selected states of stress, the maximum quantum yield for primary photochemistry (Fv/Fm), and LEF decreased in an identical way as the measured quantum yields derived from OJIP curves. A smaller decrease was found in the CEF efficiency, suggesting that this process was more resistant to the applied water stress (Figure 2B). Our results from BN-PAGE showed bands representing the typical organization of the photosynthetic apparatus in plants: PSII dimer (PSII [2]); PSII monomer (PSII [1]); cytochrome b6f complex (Cytb6f); light-harvesting complex II (LHCII) assemblies; LHCII, as well as high molecular weight supercomplexes consisting of different forms of PSII (LHCIIsc), (Figure 2C). During the transition from C–D1 state, the higher molecular weight complexes were disassembled and the bands corresponding to PSII-LHCIIsc were reduced (Figure 2D). This decrease of PSII-LHCIIsc continued up to the D3 state. At full dry state all supercomplexes were disassembled and the abundance of PSII dimers also declined. In addition decline of cytochrome b6f complex content in thylakoids has been observed during D2–D3 state transition. During rewatering, the supercomplexes were partially recovered at R1 state and fully recovered at R2 state. These observations might suggest a relation between changes in the relative abundance/functional assembly of PSII and the main electron transport carrier-cytochrome b6f complex (Figure 2D) and the relative contribution of PSII-driven LEF and PSI -driven electron flow during desiccation (Figure 2B).

Bottom Line: The NMR fingerprint shows the significant metabolic changes in several pathways.We found a decline of valine accompanied by lipid degradation during stress, likely to provide alternative carbon sources for sucrose accumulation at late stages of desiccation.This accumulation, as well as the increased levels of glycerophosphodiesters during drought stress could provide osmoprotection to the cells.

View Article: PubMed Central - PubMed

Affiliation: Abiotic Stress Group, Agrobioinstitute, Agricultural Academy Sofia, Bulgaria.

ABSTRACT
The resurrection plant Haberlea rhodopensis was used to study dynamics of drought response of photosynthetic machinery parallel with changes in primary metabolism. A relation between leaf water content and photosynthetic performance was established, enabling us to perform a non-destructive evaluation of the plant water status during stress. Spectroscopic analysis of photosynthesis indicated that, at variance with linear electron flow (LEF) involving photosystem (PS) I and II, cyclic electron flow around PSI remains active till almost full dry state at the expense of the LEF, due to the changed protein organization of photosynthetic apparatus. We suggest that, this activity could have a photoprotective role and prevent a complete drop in adenosine triphosphate (ATP), in the absence of LEF, to fuel specific energy-dependent processes necessary for the survival of the plant, during the late states of desiccation. The NMR fingerprint shows the significant metabolic changes in several pathways. Due to the declining of LEF accompanied by biosynthetic reactions during desiccation, a reduction of the ATP pool during drought was observed, which was fully and quickly recovered after plants rehydration. We found a decline of valine accompanied by lipid degradation during stress, likely to provide alternative carbon sources for sucrose accumulation at late stages of desiccation. This accumulation, as well as the increased levels of glycerophosphodiesters during drought stress could provide osmoprotection to the cells.

No MeSH data available.


Related in: MedlinePlus