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Plant Physiology Oct 2016
Topics: Climate; Ecology; Ecosystem; Environment; Photosynthesis; Plant Physiological Phenomena; Stress, Physiological
PubMed: 27694394
DOI: 10.1104/pp.16.01408 -
Current Opinion in Chemical Biology Aug 2012A recent resurgence in basic and applied research on photosynthesis has been driven in part by recognition that fulfilling future food and energy requirements will... (Review)
Review
A recent resurgence in basic and applied research on photosynthesis has been driven in part by recognition that fulfilling future food and energy requirements will necessitate improvements in crop carbon-fixation efficiencies. Photosynthesis in traditional terrestrial crops is being reexamined in light of molecular strategies employed by photosynthetic microbes to enhance the activity of the Calvin cycle. Synthetic biology is well-situated to provide original approaches for compartmentalizing and enhancing photosynthetic reactions in a species independent manner. Furthermore, the elucidation of alternative carbon-fixation routes distinct from the Calvin cycle raises possibilities that novel pathways and organisms can be utilized to fix atmospheric carbon dioxide into useful materials.
Topics: Carbon Cycle; Genetic Engineering; Photosynthesis
PubMed: 22647231
DOI: 10.1016/j.cbpa.2012.05.002 -
Nature Communications Dec 2021Iron deficiency hampers photosynthesis and is associated with chlorosis. We recently showed that iron deficiency-induced chlorosis depends on phosphorus availability....
Iron deficiency hampers photosynthesis and is associated with chlorosis. We recently showed that iron deficiency-induced chlorosis depends on phosphorus availability. How plants integrate these cues to control chlorophyll accumulation is unknown. Here, we show that iron limitation downregulates photosynthesis genes in a phosphorus-dependent manner. Using transcriptomics and genome-wide association analysis, we identify two genes, PHT4;4 encoding a chloroplastic ascorbate transporter and bZIP58, encoding a nuclear transcription factor, which prevent the downregulation of photosynthesis genes leading to the stay-green phenotype under iron-phosphorus deficiency. Joint limitation of these nutrients induces ascorbate accumulation by activating expression of an ascorbate biosynthesis gene, VTC4, which requires bZIP58. Furthermore, we demonstrate that chloroplastic ascorbate transport prevents the downregulation of photosynthesis genes under iron-phosphorus combined deficiency through modulation of ROS homeostasis. Our study uncovers a ROS-mediated chloroplastic retrograde signaling pathway to adapt photosynthesis to nutrient availability.
Topics: Arabidopsis; Chlorophyll; Chloroplasts; Gene Expression Regulation, Plant; Homeostasis; Iron; Iron Deficiencies; Kinetics; Nutrients; Phosphorus; Photosynthesis; Plants; Signal Transduction; Transcriptome
PubMed: 34893639
DOI: 10.1038/s41467-021-27548-2 -
Scientific Reports Nov 2022The diurnal variation of photosynthesis, light response curve and CO response curve in Epimedium brevicornu Maxim leaves were determined with Li-6400 photosynthesis...
The diurnal variation of photosynthesis, light response curve and CO response curve in Epimedium brevicornu Maxim leaves were determined with Li-6400 photosynthesis system to evaluate the photosynthesis of E. brevicornu. Fluorescence of chlorophyll in the leaves were determined with PAM-2500 portable chlorophyll fluorescence apparatus in the study. The results showed that the midday depression of photosynthesis was very obvious in the E. brevicornu leaves. The light compensation point of E. brevicornu leaves was about 15 µmol m s. The light saturation point of E. brevicornu leaves was below 800 µmol m s, which was lower than the general sunlight intensity at noon in summer. The CO saturation point of E. brevicornu leaves was much higher than the content of CO in general air. E. brevicornu was a typical shade plant and could survive in very low sunlight. E. brevicornu could not endure strong sunlight and high air temperature. The net photosynthetic rate of E. brevicornu leaves linearly correlated with the content of CO in the leaf chamber when the content was below CO saturation point. E. brevicornu possessed great potential of photosynthesis.
Topics: Epimedium; Carbon Dioxide; Fluorescence; Photosynthesis; Chlorophyll; Plant Leaves
PubMed: 36376438
DOI: 10.1038/s41598-022-24165-x -
Tree Physiology Jun 2022The effect of temperature change on leaf physiology has been extensively studied in temperate trees and to some extent in boreal and tropical tree species. While...
The effect of temperature change on leaf physiology has been extensively studied in temperate trees and to some extent in boreal and tropical tree species. While increased temperature typically stimulates leaf CO2 assimilation and tree growth in high-altitude ecosystems, tropical species are often negatively affected. These trees may operate close to their temperature optima and have a limited thermal acclimation capacity due to low seasonal and historical variation in temperature. To test this hypothesis, we studied the extent to which the temperature sensitivities of leaf photosynthesis and respiration acclimate to growth temperature in four common African tropical tree species. Tree seedlings native to different altitudes and therefore adapted to different growth temperatures were cultivated at three different temperatures in climate-controlled chambers. We estimated the acclimation capacity of the temperature sensitivities of light-saturated net photosynthesis, the maximum rates of Rubisco carboxylation (Vcmax) and thylakoid electron transport (J), and dark respiration. Leaf thylakoid membrane lipid composition, nitrogen content and leaf mass per area were also analyzed. Our results showed that photosynthesis in tropical tree species acclimated to higher growth temperatures, but that this was weakest in the species originating from the coolest climate. The temperature optimum of J acclimated significantly in three species and variation in J was linked to changes in the thylakoid membrane lipid composition. For Vcmax, there was only evidence of significant acclimation of optimal temperature in the lowest elevation species. Respiration acclimated to maintain homeostasis at growth temperature in all four species. Our results suggest that the lowest elevation species is better physiologically adapted to acclimate to high growth temperatures than the highest elevation species, indicating a potential shift in competitive balance and tree community composition to the disadvantage of montane tree species in a warmer world.
Topics: Acclimatization; Carbon Dioxide; Ecosystem; Lipids; Photosynthesis; Plant Leaves; Temperature; Trees
PubMed: 35038330
DOI: 10.1093/treephys/tpac002 -
Journal of Integrative Plant Biology Feb 2022Photosynthesis started to evolve some 3.5 billion years ago CO is the substrate for photosynthesis and in the past 200-250 years, atmospheric levels have approximately... (Review)
Review
Photosynthesis started to evolve some 3.5 billion years ago CO is the substrate for photosynthesis and in the past 200-250 years, atmospheric levels have approximately doubled due to human industrial activities. However, this time span is not sufficient for adaptation mechanisms of photosynthesis to be evolutionarily manifested. Steep increases in human population, shortage of arable land and food, and climate change call for actions, now. Thanks to substantial research efforts and advances in the last century, basic knowledge of photosynthetic and primary metabolic processes can now be translated into strategies to optimize photosynthesis to its full potential in order to improve crop yields and food supply for the future. Many different approaches have been proposed in recent years, some of which have already proven successful in different crop species. Here, we summarize recent advances on modifications of the complex network of photosynthetic light reactions. These are the starting point of all biomass production and supply the energy equivalents necessary for downstream processes as well as the oxygen we breathe.
Topics: Light; Photosynthesis
PubMed: 34962073
DOI: 10.1111/jipb.13206 -
Photosynthesis Research Nov 2022I present my personal reminiscence of Paul Levine-a highly innovative scientist who did seminal work in photosynthesis. He was among the first to initiate and use a...
I present my personal reminiscence of Paul Levine-a highly innovative scientist who did seminal work in photosynthesis. He was among the first to initiate and use a genetic approach toward photosynthesis. He greatly helped in establishing the green unicellular alga Chlamydomonas reinhardtii as a powerful model system not only for understanding the function of the photosynthetic apparatus but also for studying its biogenesis and regulation. During the period he spent at Harvard, he made several ground-breaking contributions such as identifying and establishing the order of some components of the photosynthetic electron transport chain as well as determining their genetic origin. He trained many students and post-doctoral fellows several of whom later became prominent in this field and in other areas of plant science.
Topics: Humans; Chlamydomonas reinhardtii; Photosynthesis
PubMed: 36107368
DOI: 10.1007/s11120-022-00927-6 -
The Plant Cell Aug 2019The unicellular alga is a classical reference organism for studying photosynthesis, chloroplast biology, cell cycle control, and cilia structure and function. It is... (Review)
Review
The unicellular alga is a classical reference organism for studying photosynthesis, chloroplast biology, cell cycle control, and cilia structure and function. It is also an emerging model for studying sensory cilia, the production of high-value bioproducts, and in situ structural determination. Much of the early appeal of Chlamydomonas was rooted in its promise as a genetic system, but like other classic model organisms, this rise to prominence predated the discovery of the structure of DNA, whole-genome sequences, and molecular techniques for gene manipulation. The haploid genome of facilitates genetic analyses and offers many of the advantages of microbial systems applied to a photosynthetic organism. has contributed to our understanding of chloroplast-based photosynthesis and cilia biology. Despite pervasive transgene silencing, technological advances have allowed researchers to address outstanding lines of inquiry in algal research. The most thoroughly studied unicellular alga, , is the current standard for algal research, and although genome editing is still far from efficient and routine, it nevertheless serves as a template for other algae. We present a historical retrospective of the rise of to illuminate its past and present. We also present resources for current and future scientists who may wish to expand their studies to the realm of microalgae.
Topics: Chlamydomonas; Chlamydomonas reinhardtii; Chloroplasts; Gene Editing; Haploidy; Photosynthesis
PubMed: 31189738
DOI: 10.1105/tpc.18.00952 -
Journal of Nanobiotechnology Aug 2021Fluorescent carbon-dots (CDs) with multifaceted advantages have provided hope for improvement of crop growth. Near infrared (NIR) CDs would be more competitive and...
BACKGROUND
Fluorescent carbon-dots (CDs) with multifaceted advantages have provided hope for improvement of crop growth. Near infrared (NIR) CDs would be more competitive and promising than short-wavelength emissive CDs, which are not directly utilized by chloroplast. The molecular targets and underlying mechanism of these stimulative effects are rarely mentioned.
RESULTS
NIR-CDs with good mono-dispersity and hydrophily were easily prepared by a one-step microwave-assisted carbonization manner, which showed obvious UV absorptive and far-red emissive properties. The chloroplast-CDs complexes could accelerate the electron transfer from photosystem II (PS II) to photosystem I (PS I). NIR-CDs exhibited a concentration-dependent promotion effect on N. benthamiana growth by strengthening photosynthesis. We firstly demonstrated that potential mechanisms behind the photosynthesis-stimulating activity might be related to up-regulated expression of the photosynthesis and chloroplast synthesis related genes, among which PsbP and PsiK genes are the key regulators.
CONCLUSION
These results illustrated that NIR-CDs showed great potential in the applications to increase crop yields through ultraviolet light harvesting and elevated photosynthesis efficiency. This work would provide a theoretical basis for the understanding and applications of the luminescent nanomaterials (not limited to CDs) in the sunlight conversion-related sustainable agriculture.
Topics: Carbon; Chlorophyll; Fluorescent Dyes; Gene Expression Regulation, Plant; Light; Luminescence; Microwaves; Nanostructures; Photosynthesis; Photosystem I Protein Complex; Photosystem II Protein Complex; Plant Proteins; Quantum Dots; Nicotiana; Ultraviolet Rays
PubMed: 34454524
DOI: 10.1186/s12951-021-01005-0 -
Microbial Genomics Sep 2023comprises a diverse group of bacteria with various lifestyles. Although best known for their nodule-based nitrogen-fixation in symbiosis with legumes, a select group of...
comprises a diverse group of bacteria with various lifestyles. Although best known for their nodule-based nitrogen-fixation in symbiosis with legumes, a select group of bradyrhizobia are also capable of photosynthesis. This ability seems to be rare among rhizobia, and its origin and evolution in these bacteria remain a subject of substantial debate. Therefore, our aim here was to investigate the distribution and evolution of photosynthesis in using comparative genomics and representative genomes from closely related taxa in the families and . We identified photosynthesis gene clusters (PGCs) in 25 genomes belonging to three different lineages, notably the so-called Photosynthetic, and supergroups. Also, two different PGC architectures were observed. One of these, PGC1, was present in genomes from the Photosynthetic supergroup and in three genomes from a species in the supergroup. The second cluster, PGC2, was also present in some strains from the supergroup, as well as in those from the supergroup. PGC2 was largely syntenic to the cluster found in and . Bayesian ancestral state reconstruction unambiguously showed that the ancestor of lacked a PGC and that it was acquired horizontally by various lineages. Maximum-likelihood phylogenetic analyses of individual photosynthesis genes also suggested multiple acquisitions through horizontal gene transfer, followed by vertical inheritance and gene losses within the different lineages. Overall, our findings add to the existing body of knowledge on ’s evolution and provide a meaningful basis from which to explore how these PGCs and the photosynthesis itself impact the physiology and ecology of these bacteria.
Topics: Bradyrhizobium; Photosynthesis
PubMed: 37676703
DOI: 10.1099/mgen.0.001105