Enhancing photosynthesis in plants: the light reactions.
Ontology highlight
ABSTRACT:
SUBMITTER: Cardona T
PROVIDER: S-EPMC5897789 | biostudies-literature | 2018 Apr
REPOSITORIES: biostudies-literature
Publications
Enhancing photosynthesis in plants: the light reactions.
Cardona Tanai T Shao Shengxi S Nixon Peter J PJ
Essays in biochemistry 20180413 1
In this review, we highlight recent research and current ideas on how to improve the efficiency of the light reactions of photosynthesis in crops. We note that the efficiency of photosynthesis is a balance between how much energy is used for growth and the energy wasted or spent protecting the photosynthetic machinery from photodamage. There are reasons to be optimistic about enhancing photosynthetic efficiency, but many appealing ideas are still on the drawing board. It is envisioned that the c ...[more]
Similar Datasets
Project description:Light dominates the earth's climate and ecosystems via photosynthesis, and fine changes of that might cause extensive material and energy alternation. Dim light (typically less than 5 μmol photons m-2 s-1) occurs widely in terrestrial ecosystems, while the frequency, duration, and extent of that are increasing because of climate change and urbanization. Dim light is important for the microorganism in the photosynthetic process, but omitted or unconsidered in the vascular plant, because the photosynthesis in the high-light adapted vascular leaves was almost impossible. In this review, we propose limitations of photosynthesis in vascular plant leaves, then elucidate the possibility and evidence of photosynthesis in terms of energy demand, stomatal opening, photosynthetic induction, and photosynthesis-related physiological processes in dim light. This article highlights the potential and noteworthy influence of dim light on photosynthesis in vascular plant leaves, and the research gap of dim light in model application and carbon accounting.
| S-EPMC7732443 | biostudies-literature
Project description:ZmNF-YB16 is a basic NF-YB superfamily member and a member of a transcription factor complex composed of NF-YA, NF-YB, and NF-YC in maize. ZmNF-YB16 was transformed into the inbred maize line B104 to produce homozygous overexpression lines. ZmNF-YB16 overexpression improves dehydration and drought stress resistance in maize plants during vegetative and reproductive stages by maintaining higher photosynthesis and increases the maize grain yield under normal and drought stress conditions. Based on the examination of differentially expressed genes between the wild-type (WT) and transgenic lines by quantitative real time PCR (qRT-PCR), ZmNF-YB16 overexpression increased the expression of genes encoding antioxidant enzymes, the antioxidant synthase, and molecular chaperones associated with the endoplasmic reticulum (ER) stress response, and improved protection mechanism for photosynthesis system II. Plants that overexpression ZmNF-YB16 showed a higher rate of photosynthesis and antioxidant enzyme activity, better membrane stability and lower electrolyte leakage under control and drought stress conditions. These results suggested that ZmNF-YB16 played an important role in drought resistance in maize by regulating the expression of a number of genes involved in photosynthesis, the cellular antioxidant capacity and the ER stress response.
| S-EPMC5986874 | biostudies-literature
Project description:Urban plants are currently confronted with the stresses posed by artificial light at night (ALAN) and drought. A field block experiment was designed to explore the potential effects of ALAN and drought on the photosynthesis and physiological characters of two common urban plants, Euonymus japonicus (E. japonicus) and Rosa hybrida (R. hybrida). Each plant species was subjected to four distinct treatments: neither ALAN nor drought, ALAN, drought, and both ALAN and drought. The result showed the following: (1) ALAN significantly reduced the effective quantum yield (ΦPSII), apparent electron transfer rate (ETR), photochemical quenching parameter (qp), net photosynthetic (Pn), stomatal conductance (Gs), stomatal limit value (Ls), and the pigment concentrations and remarkably increased the content of malondialdehyde (MDA), total antioxidant capacity (TAC), and starch in both E. japonicus and R. hybrida. Furthermore, ALAN increased the soluble saccharides of E. japonicus, and this effect of ALAN also occurred on R. hybrida under drought. (2) Drought significantly decreased the ΦPSII, ETR, qp, Pn, Gs, Ls, and the pigment concentrations and remarkably increased the content of MDA and TAC for both E. japonicus and R. hybrida. Moreover, drought did not significantly change the starch content of both species, and it significantly increased the content of soluble saccharides for E. japonicus. (3) The interaction between ALAN and drought occurred on the ΦPSII, ETR, Pn, MDA, and TAC of E. japonicus, but had no effect on R. hybrida. For urban areas affected by ALAN and drought, it is advisable to select plant species with strong stress resistance for gardening purposes, and plants directly exposed to ALAN should receive sufficient water during hot and dry weather conditions to maintain their normal growth.
| S-EPMC10602676 | biostudies-literature
Project description:As the natural-born photoelectrolyzer for oxygen delivery, photosystem II (PSII) is hardly replicated with man-made constructs. However, building on the "quantasome" hypothesis ( Science 1964, 144, 1009-1011), PSII mimicry can be pared down to essentials by shaping a photocatalytic ensemble (from the Greek term "soma" = body) where visible-light quanta trigger water oxidation. PSII-inspired quantasomes (QS) readily self-assemble into hierarchical photosynthetic nanostacks, made of bis-cationic perylenebisimides (PBI2+) as chromophores and deca-anionic tetraruthenate polyoxometalates (Ru4POM) as water oxidation catalysts ( Nat. Chem. 2019, 11, 146-153). A combined supramolecular and click-chemistry strategy is used herein to interlock the PBI-QS with tetraethylene glycol (TEG) cross-linkers, yielding QS-TEGlock with increased water solvation, controlled growth, and up to a 340% enhancement of the oxygenic photocurrent compared to the first generation QS, as probed on 3D-inverse opal indium tin oxide electrodes at 8.5 sun irradiance (λ > 450 nm, 1.28 V vs RHE applied bias, TOFmax = 0.096 ± 0.005 s-1, FEO2 > 95%). Action spectra, catalyst mass-activity, light-management, photoelectrochemical impedance spectroscopy (PEIS) together with Raman mapping of TEG-templated hydration shells point to a key role of the cross-linked PBI/Ru4POM nanoarrays, where the interplay of hydrophilic/hydrophobic domains is reminiscent of PSII-rich natural thylakoids.
| S-EPMC9376926 | biostudies-literature
Project description:Photosynthesis is not only essential for plants, but it also sustains life on Earth. Phytohormones play crucial roles in developmental processes, from organ initiation to senescence, due to their role as growth and developmental regulators, as well as their central role in the regulation of photosynthesis. Furthermore, phytohormones play a major role in photoprotection of the photosynthetic apparatus under stress conditions. Here, in addition to discussing our current knowledge on the role of the phytohormones auxin, cytokinins, gibberellins, and strigolactones in promoting photosynthesis, we will also highlight the role of abscisic acid beyond stomatal closure in modulating photosynthesis and photoprotection under various stress conditions through crosstalk with ethylene, salicylates, jasmonates, and brassinosteroids. Furthermore, the role of phytohormones in controlling the production and scavenging of photosynthesis-derived reactive oxygen species, the duration and extent of photo-oxidative stress and redox signaling under stress conditions will be discussed in detail. Hormones have a significant impact on the regulation of photosynthetic processes in plants under both optimal and stress conditions, with hormonal interactions, complementation, and crosstalk being important in the spatiotemporal and integrative regulation of photosynthetic processes during organ development at the whole-plant level.
| S-EPMC8133604 | biostudies-literature
Project description:Although some elements of the photosynthetic light reactions might appear to be ideal, the overall efficiency of light conversion to biomass has not been optimized during evolution. Because crop plants are depleted of genetic diversity for photosynthesis, efforts to enhance its efficiency with respect to light conversion to yield must generate new variation. In principle, three sources of natural variation are available: (i) rare diversity within extant higher plant species, (ii) photosynthetic variants from algae, and (iii) reconstruction of no longer extant types of plant photosynthesis. Here, we argue for a novel approach that outsources crop photosynthesis to a cyanobacterium that is amenable to adaptive evolution. This system offers numerous advantages, including a short generation time, virtually unlimited population sizes and high mutation rates, together with a versatile toolbox for genetic manipulation. On such a synthetic bacterial platform, 10 000 years of (crop) plant evolution can be recapitulated within weeks. Limitations of this system arise from its unicellular nature, which cannot reproduce all aspects of crop photosynthesis. But successful establishment of such a bacterial host for crop photosynthesis promises not only to enhance the performance of eukaryotic photosynthesis but will also reveal novel facets of the molecular basis of photosynthetic flexibility.This article is part of the themed issue 'Enhancing photosynthesis in crop plants: targets for improvement'.
| S-EPMC5566880 | biostudies-literature
Project description:In natural habitats, plants frequently experience rapid changes in the intensity of sunlight. To cope with these changes and maximize growth, plants adjust photosynthetic light utilization in electron transport and photoprotective mechanisms. This involves a proton motive force (PMF) across the thylakoid membrane, postulated to be affected by unknown anion (Cl(-)) channels. Here we report that a bestrophin-like protein from Arabidopsis thaliana functions as a voltage-dependent Cl(-) channel in electrophysiological experiments. AtVCCN1 localizes to the thylakoid membrane, and fine-tunes PMF by anion influx into the lumen during illumination, adjusting electron transport and the photoprotective mechanisms. The activity of AtVCCN1 accelerates the activation of photoprotective mechanisms on sudden shifts to high light. Our results reveal that AtVCCN1, a member of a conserved anion channel family, acts as an early component in the rapid adjustment of photosynthesis in variable light environments.
| S-EPMC4890181 | biostudies-literature
Project description:Low temperature combined with low light (LL) affects crop production, especially the yield and quality of peppers, in northwest China during the winter and spring seasons. Zeaxanthin (Z) is a known lipid protectant and active oxygen scavenger. However, whether exogenous Z can mitigate LL-induced inhibition of photosynthesis and oxidative stress in peppers remains unclear. In this study, we investigated the effects of exogenous Z on photosynthesis and the antioxidant machinery of pepper seedlings subject to LL stress. The results showed that the growth and photosynthesis of pepper seedlings were significantly inhibited by LL stress. In addition, the antioxidant machinery was disturbed by the uneven production and elimination of reactive oxygen species (ROS), which resulted in damage to the pepper. For example, membrane lipid peroxidation increased ROS content, and so on. However, exogenous application of Z before LL stress significantly increased the plant height, stem diameter, net photosynthetic rate (Pn), and stomata, which were obviously closed at LL. The activities of antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), mono de-hydroascorbate reductase (MDHAR), de-hydroascorbate reductase (DHAR), ascorbate peroxidase (APX), and ascorbate oxidase (AAO) improved significantly due to the increased expression of CaSOD, CaCAT, CaAPX, CaMDHAR, and CaDHAR. The ascorbic (AsA) and glutathione (GSH) contents and ascorbic/dehydroascorbate (AsA/DHA) and glutathione/oxidized glutathione (GSH/GSSG) ratios also increased significantly, resulting in the effective removal of hydrogen peroxide (H2O2) and superoxide anions (O2•-) caused by LL stress. Thus, pre-treatment with Z significantly reduced ROS accumulation in pepper seedlings under LL stress by enhancing the activity of antioxidant enzymes and accumulation of components of the ascorbate-glutathione (AsA-GSH) cycle and upregulated key genes in the AsA-GSH cycle.
| S-EPMC9221838 | biostudies-literature
Project description:Light stress in plants results in damage to the water oxidizing reaction center, photosystem II (PSII). Redox signaling, through oxidative modification of amino acid side chains, has been proposed to participate in this process, but the oxidative signals have not yet been identified. Previously, we described an oxidative modification, N-formylkynurenine (NFK), of W365 in the CP43 subunit. The yield of this modification increases under light stress conditions, in parallel with the decrease in oxygen evolving activity. In this work, we show that this modification, NFK365-CP43, is present in thylakoid membranes and may be formed by reactive oxygen species produced at the Mn(4)CaO(5) cluster in the oxygen-evolving complex. NFK accumulation correlates with the extent of photoinhibition in PSII and thylakoid membranes. A modest increase in ionic strength inhibits NFK365-CP43 formation, and leads to accumulation of a new, light-induced NFK modification (NFK317) in the D1 polypeptide. Western analysis shows that D1 degradation and oligomerization occur under both sets of conditions. The NFK modifications in CP43 and D1 are found 17 and 14 Angstrom from the Mn(4)CaO(5) cluster, respectively. Based on these results, we propose that NFK is an oxidative modification that signals for damage and repair in PSII. The data suggest a two pathway model for light stress responses. These pathways involve differential, specific, oxidative modification of the CP43 or D1 polypeptides.
| S-EPMC3409137 | biostudies-literature
Project description:The light dependency of respiratory activity of two scleractinian corals was examined using O2 microsensors and CO2 exchange measurements. Light respiration increased strongly but asymptotically with elevated irradiance in both species. Light respiration in Pocillopora damicornis was higher than in Pavona decussata under low irradiance, indicating species-specific differences in light-dependent metabolic processes. Overall, the coral P. decussata exhibited higher CO2 uptake rates than P. damicornis over the experimental irradiance range. P. decussata also harboured twice as many algal symbionts and higher total protein biomass compared to P. damicornis, possibly resulting in self-shading of the symbionts and/or changes in host tissue specific light distribution. Differences in light respiration and CO2 availability could be due to host-specific characteristics that modulate the symbiont microenvironment, its photosynthesis, and hence the overall performance of the coral holobiont.
| S-EPMC4216011 | biostudies-literature