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Nature Communications Apr 2024In chloroplasts, insertion of proteins with multiple transmembrane domains (TMDs) into thylakoid membranes usually occurs in a co-translational manner. Here, we have...
In chloroplasts, insertion of proteins with multiple transmembrane domains (TMDs) into thylakoid membranes usually occurs in a co-translational manner. Here, we have characterized a thylakoid protein designated FPB1 (Facilitator of PsbB biogenesis1) which together with a previously reported factor PAM68 (Photosynthesis Affected Mutant68) is involved in assisting the biogenesis of CP47, a subunit of the Photosystem II (PSII) core. Analysis by ribosome profiling reveals increased ribosome stalling when the last TMD segment of CP47 emerges from the ribosomal tunnel in fpb1 and pam68. FPB1 interacts with PAM68 and both proteins coimmunoprecipitate with SecY/E and Alb3 as well as with some ribosomal components. Thus, our data indicate that, in coordination with the SecY/E translocon and the Alb3 integrase, FPB1 synergistically cooperates with PAM68 to facilitate the co-translational integration of the last two CP47 TMDs and the large loop between them into thylakoids and the PSII core complex.
Topics: Chloroplasts; Photosystem II Protein Complex; Ribosomes; Thylakoids
PubMed: 38600073
DOI: 10.1038/s41467-024-46863-y -
Ecotoxicology and Environmental Safety May 2024In recent decades, there has been increasing interest in elucidating the role of sulfur-containing compounds in plant metabolism, particularly emphasizing their function... (Review)
Review
In recent decades, there has been increasing interest in elucidating the role of sulfur-containing compounds in plant metabolism, particularly emphasizing their function as signaling molecules. Among these, thiocyanate (SCN), a compound imbued with sulfur and nitrogen, has emerged as a significant environmental contaminant frequently detected in irrigation water. This compound is known for its potential to adversely impact plant growth and agricultural yield. Although adopting exogenous SCN as a nitrogen source in plant cells has been the subject of thorough investigation, the fate of sulfur resulting from the assimilation of exogenous SCN has not been fully explored. There is burgeoning curiosity in probing the fate of SCN within plant systems, especially considering the possible generation of the gaseous signaling molecule, hydrogen sulfide (HS) during the metabolism of SCN. Notably, the endogenous synthesis of HS occurs predominantly within chloroplasts, the cytosol, and mitochondria. In contrast, the production of HS following the assimilation of exogenous SCN is explicitly confined to chloroplasts and mitochondria. This phenomenon indicates complex interplay and communication among various subcellular organelles, influencing signal transduction and other vital physiological processes. This review, augmented by a small-scale experimental study, endeavors to provide insights into the functional characteristics of HS signaling in plants subjected to SCN-stress. Furthermore, a comparative analysis of the occurrence and trajectory of endogenous HS and HS derived from SCN-assimilation within plant organisms was performed, providing a focused lens for a comprehensive examination of the multifaceted roles of HS in rice plants. By delving into these dimensions, our objective is to enhance the understanding of the regulatory mechanisms employed by the gasotransmitter HS in plant adaptations and responses to SCN-stress, yielding invaluable insights into strategies for plant resilience and adaptive capabilities.
Topics: Hydrogen Sulfide; Thiocyanates; Signal Transduction; Plants; Gasotransmitters; Chloroplasts; Inactivation, Metabolic
PubMed: 38593497
DOI: 10.1016/j.ecoenv.2024.116307 -
PloS One 2024Iris is a cosmopolitan genus comprising approximately 280 species distributed throughout the Northern Hemisphere. Although Iris is the most diverse group in the...
Iris is a cosmopolitan genus comprising approximately 280 species distributed throughout the Northern Hemisphere. Although Iris is the most diverse group in the Iridaceae, the number of taxa is debatable owing to various taxonomic issues. Plastid genomes have been widely used for phylogenetic research in plants; however, only limited number of plastid DNA markers are available for phylogenetic study of the Iris. To understand the genomic features of plastids within the genus, including its structural and genetic variation, we newly sequenced and analyzed the complete plastid genome of I. orchioides and compared it with those of 19 other Iris taxa. Potential plastid markers for phylogenetic research were identified by computing the sequence divergence and phylogenetic informativeness. We then tested the utility of the markers with the phylogenies inferred from the markers and whole-plastome data. The average size of the plastid genome was 152,926 bp, and the overall genomic content and organization were nearly identical among the 20 Iris taxa, except for minor variations in the inverted repeats. We identified 10 highly informative regions (matK, ndhF, rpoC2, ycf1, ycf2, rps15-ycf, rpoB-trnC, petA-psbJ, ndhG-ndhI and psbK-trnQ) and inferred a phylogeny from each region individually, as well as from their concatenated data. Remarkably, the phylogeny reconstructed from the concatenated data comprising three selected regions (rpoC2, ycf1 and ycf2) exhibited the highest congruence with the phylogeny derived from the entire plastome dataset. The result suggests that this subset of data could serve as a viable alternative to the complete plastome data, especially for molecular diagnoses among closely related Iris taxa, and at a lower cost.
Topics: Iris Plant; Phylogeny; Genome, Plastid; Genomics; Plastids; Evolution, Molecular
PubMed: 38578735
DOI: 10.1371/journal.pone.0301346 -
Advanced Science (Weinheim,... Jun 2024Plant chloroplasts have a highly compartmentalized interior, essential for executing photocatalytic functions. However, the construction of a photocatalytic reaction...
Plant chloroplasts have a highly compartmentalized interior, essential for executing photocatalytic functions. However, the construction of a photocatalytic reaction compartment similar to chloroplasts in inorganic-biological hybrid systems (IBS) has not been reported. Drawing inspiration from the compartmentalized chloroplast and the phenomenon of liquid-liquid phase separation, herein, a new strategy is first developed for constructing a photocatalytic subcellular hybrid system through liquid-liquid phase separation technology in living cells. Photosensitizers and in vivo expressed hydrogenases are designed to coassemble within the cell to create subcellular compartments for synergetic photocatalysis. This compartmentalization facilitates efficient electron transfer and light energy utilization, resulting in highly effective H production. The subcellular compartments hybrid system (HM/IBSCS) exhibits a nearly 87-fold increase in H production compared to the bare bacteria/hybrid system. Furthermore, the intracellular compartments of the photocatalytic reactor enhance the system's stability obviously, with the bacteria maintaining approximately 81% of their H production activity even after undergoing five cycles of photocatalytic hydrogen production. The research brings forward visionary prospects for the field of semi-artificial photosynthesis, offering new possibilities for advancements in areas such as renewable energy, biomanufacturing, and genetic engineering.
Topics: Hydrogen; Photosynthesis; Chloroplasts; Catalysis; Photochemical Processes; Phase Separation
PubMed: 38572522
DOI: 10.1002/advs.202400097 -
Scientific Reports Apr 2024Abies koreana E.H.Wilson is an endangered evergreen coniferous tree that is native to high altitudes in South Korea and susceptible to the effects of climate change....
Abies koreana E.H.Wilson is an endangered evergreen coniferous tree that is native to high altitudes in South Korea and susceptible to the effects of climate change. Hybridization and reticulate evolution have been reported in the genus; therefore, multigene datasets from nuclear and cytoplasmic genomes are needed to better understand its evolutionary history. Using the Illumina NovaSeq 6000 and Oxford Nanopore Technologies (ONT) PromethION platforms, we generated complete mitochondrial (1,174,803 bp) and plastid (121,341 bp) genomes from A. koreana. The mitochondrial genome is highly dynamic, transitioning from cis- to trans-splicing and breaking conserved gene clusters. In the plastome, the ONT reads revealed two structural conformations of A. koreana. The short inverted repeats (1186 bp) of the A. koreana plastome are associated with different structural types. Transcriptomic sequencing revealed 1356 sites of C-to-U RNA editing in the 41 mitochondrial genes. Using A. koreana as a reference, we additionally produced nuclear and organelle genomic sequences from eight Abies species and generated multiple datasets for maximum likelihood and network analyses. Three sections (Balsamea, Momi, and Pseudopicea) were well grouped in the nuclear phylogeny, but the phylogenomic relationships showed conflicting signals in the mitochondrial and plastid genomes, indicating a complicated evolutionary history that may have included introgressive hybridization. The obtained data illustrate that phylogenomic analyses based on sequences from differently inherited organelle genomes have resulted in conflicting trees. Organelle capture, organelle genome recombination, and incomplete lineage sorting in an ancestral heteroplasmic individual can contribute to phylogenomic discordance. We provide strong support for the relationships within Abies and new insights into the phylogenomic complexity of this genus.
Topics: Phylogeny; Abies; Base Sequence; Cycadopsida; Plastids
PubMed: 38561351
DOI: 10.1038/s41598-024-58253-x -
Nature Communications Mar 2024Plant photosynthesis contains two functional modules, the light-driven reactions in the thylakoid membrane and the carbon-fixing reactions in the chloroplast stroma. In...
Plant photosynthesis contains two functional modules, the light-driven reactions in the thylakoid membrane and the carbon-fixing reactions in the chloroplast stroma. In nature, light availability for photosynthesis often undergoes massive and rapid fluctuations. Efficient and productive use of such variable light supply requires an instant crosstalk and rapid synchronization of both functional modules. Here, we show that this communication involves the stromal exposed C-terminus of the thylakoid K-exchange antiporter KEA3, which regulates the ΔpH across the thylakoid membrane and therefore pH-dependent photoprotection. By combining in silico, in vitro, and in vivo approaches, we demonstrate that the KEA3 C-terminus senses the energy state of the chloroplast in a pH-dependent manner and regulates transport activity in response. Together our data pinpoint a regulatory feedback loop by which the stromal energy state orchestrates light capture and photoprotection via multi-level regulation of KEA3.
Topics: Thylakoids; Protons; Antiporters; Arabidopsis Proteins; Arabidopsis; Photosynthesis; Chloroplasts; Light
PubMed: 38555362
DOI: 10.1038/s41467-024-47151-5 -
Genes Mar 2024Siebold & Zucc. (Hamamelidaceae) is widely used as a horticultural plant and comprises approximately 25 species in East Asia. Molecular research is essential to...
Siebold & Zucc. (Hamamelidaceae) is widely used as a horticultural plant and comprises approximately 25 species in East Asia. Molecular research is essential to distinguish species, which are morphologically similar. Molecular research has been conducted using a small number of genes but not in . Plastid genomes of species (, and ) were sequenced using next-generation sequencing techniques. Repeats and nucleotide diversity that could be used as DNA markers were also investigated. A phylogenetic investigation was carried out using 79 protein-coding genes to infer the evolutionary relationships within the genus . By including new plastomes, the overall plastid genome structure of was similar. Simple sequence repeats of 73-106 SSRs were identified in the protein-coding genes of the plastid genomes, and 33-40 long repeat sequences were identified in the plastomes. The Pi value of the region, an intergenic spacer, was the highest. Phylogenetic analysis demonstrated that is a monophyletic group and is closely related to . , and formed a clade distributed in Japan, whereas , , and formed a clade that was distributed in China.
Topics: Phylogeny; Biological Evolution; Plastids; Genome, Plastid; Hamamelidaceae
PubMed: 38540439
DOI: 10.3390/genes15030380 -
Journal of Biosciences 2024Stomatal guard cells are unique in that they have more mitochondria than chloroplasts. Several reports emphasized the importance of mitochondria as the major energy...
Stomatal guard cells are unique in that they have more mitochondria than chloroplasts. Several reports emphasized the importance of mitochondria as the major energy source during stomatal opening. We re-examined their role during stomatal closure. The marked sensitivity of stomata to both menadione (MD) and methyl viologen (MV) demonstrated that both mitochondria and chloroplasts helped to promote stomatal closure in Arabidopsis. As in the case of abscisic acid (ABA), a plant stress hormone, MD and MV induced stomatal closure at micromolar concentration. All three compounds generated superoxide and HO, as indicated by fluorescence probes, BES-So-AM and CM-HDCFDA, respectively. Results from tiron (a superoxide scavenger) and catalase (an HO scavenger) confirmed that both the superoxide and HO were requisites for stomatal closure. Co-localization of the superoxide and HO in mitochondria and chloroplasts using fluorescent probes revealed that exposure to MV initially triggered higher superoxide and H2O2 generation in mitochondria. In contrast, MD elevated superoxide/H2O2 levels in chloroplasts. However, with prolonged exposure, MD and MV induced ROS production in other organelles. We conclude that ROS production in mitochondria and chloroplasts leads to stomatal closure. We propose that stomatal guard cells can be good models for examining inter-organellar interactions.
Topics: Arabidopsis; Hydrogen Peroxide; Superoxides; Reactive Oxygen Species; Plant Stomata; Signal Transduction; Plant Growth Regulators; Abscisic Acid; Arabidopsis Proteins; Chloroplasts; Mitochondria
PubMed: 38516911
DOI: No ID Found -
Scientific Reports Mar 2024Poor germination and seedlings growth can lead to significant economic losses for farmers, therefore, sustainable agricultural strategies to improve germination and...
Poor germination and seedlings growth can lead to significant economic losses for farmers, therefore, sustainable agricultural strategies to improve germination and early growth of crops are urgently needed. The objective of this work was to evaluate selenium nanoparticles (Se NPs) as nanopriming agents for tomato (Solanum lycopersicum) seeds germinated without stress conditions in both trays and Petri dishes. Germination quality, seedlings growth, synergism-antagonism of Se with other elements, and fate of Se NPs, were determined as function of different Se NPs concentrations (1, 10 and 50 ppm). Results indicated that the germination rate in Petri dishes improved with 10 ppm, while germination trays presented the best results at 1 ppm, increasing by 10 and 32.5%, respectively. Therefore, seedlings growth was measured only in germination trays. Proline content decreased up to 22.19% with 10 ppm, while for same treatment, the total antioxidant capacity (TAC) and total chlorophyll content increased up to 38.97% and 21.28%, respectively. Antagonisms between Se with Mg, K, Mn, Zn, Fe, Cu and Mo in the seed were confirmed. In the case of seedlings, the N content decreased as the Se content increased. Transmission Electron Microscopy (TEM) imaging confirmed that Se NPs surrounded the plastids of the seed cells. By this finding, it can be inferred that Se NPs can reach the embryo, which is supported by the antagonism of Se with important nutrients involved in embryogenesis, such as K, Mg and Fe, and resulted in a better germination quality. Moreover, the positive effect of Se NPs on total chlorophyll and TAC, and the negative correlation with proline content with Se content in the seed, can be explained by Se NPs interactions with proplastids and other organelles within the cells, resulting with the highest length and fresh weight when seeds were exposed to 1 ppm.
Topics: Seedlings; Germination; Selenium; Solanum lycopersicum; Nanoparticles; Antioxidants; Seeds; Chlorophyll; Proline
PubMed: 38509209
DOI: 10.1038/s41598-024-57049-3 -
Plant Biotechnology Journal Mar 2024Building sustainable platforms to produce biofuels and specialty chemicals has become an increasingly important strategy to supplement and replace fossil fuels and...
Building sustainable platforms to produce biofuels and specialty chemicals has become an increasingly important strategy to supplement and replace fossil fuels and petrochemical-derived products. Terpenoids are the most diverse class of natural products that have many commercial roles as specialty chemicals. Poplar is a fast growing, biomassdense bioenergy crop with many species known to produce large amounts of the hemiterpene isoprene, suggesting an inherent capacity to produce significant quantities of other terpenes. Here we aimed to engineer poplar with optimized pathways to produce squalene, a triterpene commonly used in cosmetic oils, a potential biofuel candidate, and the precursor to the further diversified classes of triterpenoids and sterols. The squalene production pathways were either re-targeted from the cytosol to plastids or co-produced with lipid droplets in the cytosol. Squalene and lipid droplet co-production appeared to be toxic, which we hypothesize to be due to disruption of adventitious root formation, suggesting a need for tissue specific production. Plastidial squalene production enabled up to 0.63 mg/g fresh weight in leaf tissue, which also resulted in reductions in isoprene emission and photosynthesis. These results were also studied through a technoeconomic analysis, providing further insight into developing poplar as a production host.
PubMed: 38507185
DOI: 10.1111/pbi.14345