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PloS One 2024Aluminum (Al) toxicity is an important factor restricting the normal growth of plants in acidic soil. Rhododendron (Ericaceae) can grow relatively well in acidic soil....
Aluminum (Al) toxicity is an important factor restricting the normal growth of plants in acidic soil. Rhododendron (Ericaceae) can grow relatively well in acidic soil. To uncover the adaptive mechanisms of photosynthesis under Al stress, the influence of Al stress on the photosynthetic activities of Al-sensitive (Baijinpao) and Al-resistant (Kangnaixin) rhododendron cultivars was examined by measuring gas exchange, chlorophyll fluorescence, and the modulated reflection of light at 820 nm. Under Al stress conditions, the net photosynthetic rate and stomatal conductance of the rhododendron leaves decreased, whereas the intercellular CO2 concentration increased. The Al stress treatment damaged the oxygen-evolving complex of the rhododendron seedlings, while also inhibiting electron transport on the photosystem II (PSII) donor side. In addition, the exposure to Al stress restricted the oxidation of plastocyanin (PC) and the photosystem I (PSI) reaction center (P700) and led to the re-reduction of PC+ and P700+. The comparison with Kangnaixin revealed an increase in the PSII connectivity in Baijinpao. Additionally, the donor-side electron transport efficiency was more inhibited and the overall activity of PSII, PSI, and the intersystem electron transport chain decreased more extensively in Baijinpao than in Kangnaixin. On the basis of the study findings, we concluded that Al stress adversely affects photosynthesis in rhododendron seedlings by significantly decreasing the activity of PSII and PSI. Under Al stress, Kangnaixin showed stronger tolerance compared with Baijinpao.
Topics: Rhododendron; Aluminum; Chlorophyll; Photosynthesis; Fluorescence; Photosystem II Protein Complex; Stress, Physiological; Plant Leaves; Electron Transport; Light; Photosystem I Protein Complex
PubMed: 38935623
DOI: 10.1371/journal.pone.0305133 -
Molecules (Basel, Switzerland) Jun 2024Research over the last 25 years related to structural elucidations and biological investigations of the specialized pro-resolving mediators has spurred great interest in... (Review)
Review
Research over the last 25 years related to structural elucidations and biological investigations of the specialized pro-resolving mediators has spurred great interest in targeting these endogenous products in total synthesis. These lipid mediators govern the resolution of inflammation as potent and stereoselective agonists toward individual G-protein-coupled receptors, resulting in potent anti-inflammatory activities demonstrated in many human disease models. Specialized pro-resolving mediators are oxygenated polyunsaturated products formed in stereoselective and distinct biosynthetic pathways initiated by various lipoxygenase and cyclooxygenase enzymes. In this review, the reported stereoselective total synthesis and biological activities of the specialized pro-resolving mediators biosynthesized from the polyunsaturated fatty acid n-3 docosapentaenoic acid are presented.
Topics: Humans; Fatty Acids, Unsaturated; Animals; Prostaglandin-Endoperoxide Synthases; Anti-Inflammatory Agents; Inflammation
PubMed: 38930898
DOI: 10.3390/molecules29122833 -
International Journal of Molecular... Jun 2024Water deficit is the major stress factor magnified by climate change that causes the most reductions in plant productivity. Knowledge of photosystem II (PSII) response...
Water deficit is the major stress factor magnified by climate change that causes the most reductions in plant productivity. Knowledge of photosystem II (PSII) response mechanisms underlying crop vulnerability to drought is critical to better understanding the consequences of climate change on crop plants. Salicylic acid (SA) application under drought stress may stimulate PSII function, although the exact mechanism remains essentially unclear. To reveal the PSII response mechanism of celery plants sprayed with water (WA) or SA, we employed chlorophyll fluorescence imaging analysis at 48 h, 96 h, and 192 h after watering. The results showed that up to 96 h after watering, the stroma lamellae of SA-sprayed leaves appeared dilated, and the efficiency of PSII declined, compared to WA-sprayed plants, which displayed a better PSII function. However, 192 h after watering, the stroma lamellae of SA-sprayed leaves was restored, while SA boosted chlorophyll synthesis, and by ameliorating the osmotic potential of celery plants, it resulted in higher relative leaf water content compared to WA-sprayed plants. SA, by acting as an antioxidant under drought stress, suppressed phototoxicity, thereby offering PSII photoprotection, together with enhanced effective quantum yield of PSII photochemistry (Φ) and decreased quantity of singlet oxygen (O) generation compared to WA-sprayed plants. The PSII photoprotection mechanism induced by SA under drought stress was triggered by non-photochemical quenching (NPQ), which is a strategy to protect the chloroplast from photo-oxidative damage by dissipating the excess light energy as heat. This photoprotective mechanism, triggered by NPQ under drought stress, was adequate in keeping, especially in high-light conditions, an equal fraction of open PSII reaction centers (q) as of non-stress conditions. Thus, under water deficit stress, SA activates a regulatory network of stress and light energy partitioning signaling that can mitigate, to an extent, the water deficit stress on PSII functioning.
Topics: Photosystem II Protein Complex; Salicylic Acid; Plant Leaves; Chlorophyll; Apium; Droughts; Water; Photosynthesis; Dehydration; Stress, Physiological
PubMed: 38928427
DOI: 10.3390/ijms25126721 -
International Journal of Molecular... Jun 2024Parkinson's disease (PD) is the second most prevalent neurodegenerative disorder currently affecting the ageing population. Although the aetiology of PD has yet to be...
Parkinson's disease (PD) is the second most prevalent neurodegenerative disorder currently affecting the ageing population. Although the aetiology of PD has yet to be fully elucidated, environmental factors such as exposure to the naturally occurring neurotoxin rotenone has been associated with an increased risk of developing PD. Rotenone inhibits mitochondrial respiratory chain (MRC) complex I activity as well as induces dopaminergic neuronal death. The aim of the present study was to investigate the underlying mechanisms of rotenone-induced mitochondrial dysfunction and oxidative stress in an in vitro SH-SY5Y neuronal cell model of PD and to assess the ability of pre-treatment with Coenzyme Q (CoQ) to ameliorate oxidative stress in this model. Spectrophotometric determination of the mitochondrial enzyme activities and fluorescence probe studies of reactive oxygen species (ROS) production was assessed. Significant inhibition of MRC complex I and II-III activities was observed, together with a significant loss of neuronal viability, CoQ status, and ATP synthesis. Additionally, significant increases were observed in intracellular and mitochondrial ROS production. Remarkably, CoQ supplementation was found to reduce ROS formation. These results have indicated mitochondrial dysfunction and increased oxidative stress in a rotenone-induced neuronal cell model of PD that was ameliorated by CoQ supplementation.
Topics: Ubiquinone; Rotenone; Mitochondria; Humans; Oxidative Stress; Reactive Oxygen Species; Neurons; Parkinson Disease; Cell Line, Tumor; Muscle Weakness; Cell Survival; Electron Transport Complex I; Ataxia; Mitochondrial Diseases
PubMed: 38928331
DOI: 10.3390/ijms25126622 -
International Journal of Molecular... Jun 2024Proteasome 26S Subunit, Non-ATPase 9 () plays an important role in the balance of protamine and the stability of the nucleolar structure during spermatogenesis. In this...
Proteasome 26S Subunit, Non-ATPase 9 () plays an important role in the balance of protamine and the stability of the nucleolar structure during spermatogenesis. In this study, we cloned the of and analyzed its expression pattern. was identified on the Z chromosome of , which is considered an interesting candidate gene for spermatogenesis. qRT-PCR and FISH experiments showed that the gene was significantly highly expressed in the testes. It is worth noting that the expression level of in male fish testes is significantly higher than that in pseudomales. In order to further explore the role of in spermatogenesis, a male testicular cell line was used as the experimental material. The results of the -RNAi and overexpression experiments showed that had a synergistic effect with spermatogenesis-related genes , , and , but had an antagonistic effect with . Our findings offer a scientific foundation for comprehending the role of in the spermatogenesis regulatory network of .
Topics: Animals; Spermatogenesis; Male; Testis; Sex Chromosomes; Fish Proteins; Proteasome Endopeptidase Complex; Cloning, Molecular
PubMed: 38928079
DOI: 10.3390/ijms25126372 -
Genes Jun 2024We conducted transcriptome sequencing on salt-tolerant mutants X5 and X3, and a control (Ctr) strain of after treatment with artificial seawater at varying salinities...
We conducted transcriptome sequencing on salt-tolerant mutants X5 and X3, and a control (Ctr) strain of after treatment with artificial seawater at varying salinities (30‱, 45‱, and 60‱) for 3 weeks. Differentially expressed genes were identified and a weighted co-expression network analysis was conducted. The blue, red, and tan modules were most closely associated with salinity, while the black, cyan, light cyan, and yellow modules showed a close correlation with strain attributes. KEGG enrichment of genes from the aforementioned modules revealed that the key enrichment pathways for salinity attributes included the proteasome and carbon fixation in photosynthesis, whereas the key pathways for strain attributes consisted of lipid metabolism, oxidative phosphorylation, soluble N-ethylmaleimide-sensitive factor-activating protein receptor (SNARE) interactions in vesicular transport, and porphyrin and chlorophyll metabolism. Gene expression for the proteasome and carbon fixation in photosynthesis was higher in all strains at 60‱. In addition, gene expression in the proteasome pathway was higher in the X5-60 than Ctr-60 and X3-60. Based on the above data and relevant literature, we speculated that mutant X5 likely copes with high salt stress by upregulating genes related to lysosome and carbon fixation in photosynthesis. The proteasome may be reset to adjust the organism's proteome composition to adapt to high-salt environments, while carbon fixation may aid in maintaining material and energy metabolism for normal life activities by enhancing carbon dioxide uptake via photosynthesis. The differences between the X5-30 and Ctr-30 expression of genes involved in the synthesis of secondary metabolites, oxidative phosphorylation, and SNARE interactions in vesicular transport suggested that the X5-30 may differ from Ctr-30 in lipid metabolism, energy metabolism, and vesicular transport. Finally, among the key pathways with good correlation with salinity and strain traits, the key genes with significant correlation with salinity and strain traits were identified by correlation analysis.
Topics: Salt Tolerance; Transcriptome; Gene Regulatory Networks; Salinity; Photosynthesis; Osmotic Pressure; Proteasome Endopeptidase Complex; Gene Expression Profiling; Lipid Metabolism
PubMed: 38927717
DOI: 10.3390/genes15060781 -
Genes May 2024The Cosmonaut Sea is one of the least accessed regions in the Southern Ocean, and our knowledge about the fish biodiversity in the region is sparse. In this study, we...
The Cosmonaut Sea is one of the least accessed regions in the Southern Ocean, and our knowledge about the fish biodiversity in the region is sparse. In this study, we provided a description of demersal fish diversity in the Cosmonaut Sea by analysing cytochrome oxidase I () barcodes of 98 fish samples that were hauled by trawling during the 37th and 38th Chinese National Antarctic Research Expedition (CHINARE) cruises. Twenty-four species representing 19 genera and 11 families, namely, Artedidraconidae, Bathydraconidae, Bathylagidae, Channichthyidae, Liparidae, Macrouridae, Muraenolepididae, Myctophidae, Nototheniidae, Paralepididae and Zoarcidae, were discriminated and identified, which were largely identical to local fish occurrence records and the general pattern of demersal fish communities at high Antarctic shelf areas. The validity of a barcoding gap failed to be detected and confirmed across all species due to the indicative signals of two potential cryptic species. Nevertheless, DNA barcoding still demonstrated to be a very efficient and sound method for the discrimination and classification of Antarctic fishes. In the future, various sampling strategies that cover all geographic sections and depth strata of the Cosmonaut Sea are encouraged to enhance our understanding of local fish communities, within which DNA barcoding can play an important role in either molecular taxonomy or the establishment of a dedicated local reference database for eDNA metabarcoding analyses.
Topics: Animals; DNA Barcoding, Taxonomic; Fishes; Biodiversity; Antarctic Regions; Electron Transport Complex IV; Phylogeny; Oceans and Seas
PubMed: 38927627
DOI: 10.3390/genes15060691 -
Genes May 2024A 23-month-old neutered male dog of unknown ancestry presented with a history of progressive neurological signs that included anxiety, cognitive impairment, tremors,...
A 23-month-old neutered male dog of unknown ancestry presented with a history of progressive neurological signs that included anxiety, cognitive impairment, tremors, seizure activity, ataxia, and pronounced visual impairment. The clinical signs were accompanied by global brain atrophy. Due to progression in the severity of disease signs, the dog was euthanized at 26 months of age. An examination of the tissues collected at necropsy revealed dramatic intracellular accumulations of autofluorescent inclusions in the brain, retina, and cardiac muscle. The inclusions were immunopositive for subunit c of mitochondrial ATP synthase, and their ultrastructural appearances were similar to those of lysosomal storage bodies that accumulate in some neuronal ceroid lipofuscinosis (NCL) diseases. The dog also exhibited widespread neuroinflammation. Based on these findings, the dog was deemed likely to have suffered from a form of NCL. A whole genome sequence analysis of the proband's DNA revealed a homozygous C to T substitution that altered the intron 3-exon 4 splice site of . Other mutations in cause NCL diseases in humans and animals, including dogs. The CLN6 protein was undetectable with immunolabeling in the tissues of the proband. Based on the clinical history, fluorescence and electron-microscopy, immunohistochemistry, and molecular genetic findings, the disorder in this dog was classified as an NCL resulting from the absence of the CLN6 protein. Screening the dog's genome for a panel of breed-specific polymorphisms indicated that its ancestry included numerous breeds, with no single breed predominating. This suggests that the disease variant is likely to be present in other mixed-breed dogs and at least some ancestral breeds, although it is likely to be rare since other cases have not been reported to date.
Topics: Neuronal Ceroid-Lipofuscinoses; Animals; Dogs; Male; Dog Diseases; RNA Splice Sites; Membrane Proteins; Mitochondrial Proton-Translocating ATPases; Brain; Mutation
PubMed: 38927597
DOI: 10.3390/genes15060661 -
Biomolecules May 2024The p53 protein is the master regulator of cellular integrity, primarily due to its tumor-suppressing functions. Approximately half of all human cancers carry mutations... (Review)
Review
The p53 protein is the master regulator of cellular integrity, primarily due to its tumor-suppressing functions. Approximately half of all human cancers carry mutations in the TP53 gene, which not only abrogate the tumor-suppressive functions but also confer p53 mutant proteins with oncogenic potential. The latter is achieved through so-called gain-of-function (GOF) mutations that promote cancer progression, metastasis, and therapy resistance by deregulating transcriptional networks, signaling pathways, metabolism, immune surveillance, and cellular compositions of the microenvironment. Despite recent progress in understanding the complexity of mutp53 in neoplastic development, the exact mechanisms of how mutp53 contributes to cancer development and how they escape proteasomal and lysosomal degradation remain only partially understood. In this review, we address recent findings in the field of oncogenic functions of mutp53 specifically regarding, but not limited to, its implications in metabolic pathways, the secretome of cancer cells, the cancer microenvironment, and the regulating scenarios of the aberrant proteasomal degradation. By analyzing proteasomal and lysosomal protein degradation, as well as its connection with autophagy, we propose new therapeutical approaches that aim to destabilize mutp53 proteins and deactivate its oncogenic functions, thereby providing a fundamental basis for further investigation and rational treatment approaches for TP53-mutated cancers.
Topics: Humans; Tumor Suppressor Protein p53; Neoplasms; Tumor Microenvironment; Proteolysis; Proteasome Endopeptidase Complex; Autophagy; Animals; Mutation; Lysosomes; Carcinogenesis
PubMed: 38927053
DOI: 10.3390/biom14060649 -
Biomolecules May 2024The exosome multiprotein complex plays a critical role in RNA processing and degradation. This system governs the regulation of mRNA quality, degradation in the...
The exosome multiprotein complex plays a critical role in RNA processing and degradation. This system governs the regulation of mRNA quality, degradation in the cytoplasm, the processing of short noncoding RNA, and the breakdown of RNA fragments. We determined two crystal structures of exosome components from (): one with a resolution of 2.3 Å that reveals the central components (Rrp41 and Rrp42), and another with a resolution of 3.5 Å that displays the whole exosome (Rrp41, Rrp42, and Rrp4). The fundamental exosome structure revealed the presence of a heterodimeric complex consisting of Rrp41 and Rrp42. The structure comprises nine subunits, with Rrp41 and Rrp42 arranged in a circular configuration, while Rrp4 is located at the apex. The RNA degradation capabilities of the Rrp4:41:42 complex were verified by RNA degradation assays, consistent with prior findings in other archaeal exosomes. The resemblance between archaeal exosomes and bacterial PNPase suggests a common mechanism for RNA degradation. Despite sharing comparable topologies, the surface charge distributions of Rrp4 and other archaea structures are surprisingly distinct. Different RNA breakdown substrates may be responsible for this variation. These newfound structural findings enhance our comprehension of RNA processing and degradation in biological systems.
Topics: Thermoplasma; Exosomes; Crystallography, X-Ray; Archaeal Proteins; Models, Molecular; Protein Subunits; Exosome Multienzyme Ribonuclease Complex; RNA Stability
PubMed: 38927025
DOI: 10.3390/biom14060621