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Low-temperature germination (LTG) is an important agronomic trait for direct-seeding cultivation of rice (Oryza sativa). Both OsMYB30 and OsTPP1 regulate the cold stress response in rice, but the function of OsMYB30 and OsTPP1 in regulating LTG and the underlying molecular mechanism remains unknown. Employing transcriptomics and functional studies revealed a sugar signaling pathway that regulates seed germination in response to low temperature (LT). Expression of OsMYB30 and OsTPP1 was induced by LT during seed germination, and overexpressing either OsMYB30 or OsTPP1 delayed seed germination and increased sensitivity to LT during seed germination. Transcriptomics and qPCR revealed that expression of OsTPP1 was upregulated in OsMYB30-overexpressing lines but downregulated in OsMYB30-knockout lines. In vitro and in vivo experiments revealed that OsMYB30 bound to the promoter of OsTPP1 and regulated the abundance of OsTPP1 transcripts. Overaccumulation of trehalose (Tre) was found in both OsMYB30- and OsTPP1-overexpressing lines, resulting in inhibition of α-amylase 1a (OsAMY1a) gene during seed germination. Both LT and exogenous Tre treatments suppressed the expression of OsAMY1a, and the osamy1a mutant was not sensitive to exogenous Tre during seed germination. Overall, we concluded that OsMYB30 expression was induced by LT to activate the expression of OsTPP1 and increase Tre content, which thus inhibited α-amylase activity and seed germination. This study identified a phytohormone-independent pathway that integrates environmental cues with internal factors to control seed germination.
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Oryza , Fatores de Transcrição , Fatores de Transcrição/genética , Germinação/genética , Trealose , alfa-Amilases/genética , Temperatura , Sementes/genética , Oryza/genéticaRESUMO
Grain size is a key factor in determining rice (Oryza sativa) yield, and exploring new pathways to regulate grain size has immense potential to improve yield. In this study, we report that OsCBL5 encodes a calcineurin B subunit protein that significantly promotes grain size and weight. oscbl5 plants produced obviously smaller and lighter seeds. We further revealed that OsCBL5 promotes grain size by affecting cell expansion in the spikelet hull. Biochemical analyses demonstrated that CBL5 interacts with CIPK1 and PP23. Furthermore, double and triple mutations were induced using CRISPR/Cas9 (cr) to analyze the genetic relationship. It was found that the cr-cbl5/cipk1 phenotype was similar to that of cr-cipk1 and that the cr-cbl5/pp23, cr-cipk1/pp23, and cr-cbl5/cipk1/pp23 phenotype was similar to that of cr-pp23, indicating that OsCBL5, CIPK1, and PP23 act as a molecular module influencing seed size. In addition, the results show that both CBL5 and CIPK1 are involved in the gibberellic acid (GA) pathway and significantly affect the accumulation of endogenous active GA4 . PP23 participates in GA signal transduction. In brief, this study identified a new module that affects rice grain size, OsCBL5-CIPK1-PP23, which could potentially be targeted to improve rice yield.
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Giberelinas , Oryza , Giberelinas/metabolismo , Oryza/genética , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Grão Comestível/genética , Regulação da Expressão Gênica de PlantasRESUMO
Interacting fermionic ladders are versatile platforms to study quantum phases of matter, such as different types of Mott insulators. In particular, there are D-Mott and S-Mott states that hold preformed fermion pairs and become paired-fermion liquids upon doping (d wave and s wave, respectively). We show that the D-Mott and S-Mott phases are in fact two facets of the same topological phase and that the transition between them is terminable. These results provide a quantum analog of the well-known terminable liquid-to-gas transition. However, the phenomenology we uncover is even richer, as the order of the transition may alternate between continuous and first order, depending on the interaction details. Most importantly, the terminable transition is robust in the sense that it is guaranteed to appear for weak, but arbitrary couplings. We discuss a minimal model where some analytical insights can be obtained, a generic model where the effect persists; and a model-independent field-theoretical study demonstrating the general phenomenon. The role of symmetry and the edge states is briefly discussed. The numerical results are obtained using the variational uniform matrix-product state (VUMPS) formalism for infinite systems, as well as the density-matrix renormalization group (DMRG) algorithm for finite systems.
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A series of recent experimental works on twisted MoTe_{2} homobilayers have unveiled an abundance of exotic states in this system. Valley-polarized quantum anomalous Hall states have been identified at hole doping of ν=-1, and the fractional quantum anomalous Hall effect is observed at ν=-2/3 and ν=-3/5. In this Letter, we investigate the electronic properties of AA-stacked twisted bilayer MoTe_{2} at ν=-2 by k-space Hartree-Fock calculations. We identify a series of phases, among which a noteworthy phase is the antiferromagnetic Chern insulator, stabilized by an external electric field. We attribute the existence of this Chern insulator to an antiferromagnetic instability at a topological phase transition between the quantum spin hall phase and a band insulator phase. Our research proposes the potential of realizing a Chern insulator beyond ν=-1, and contributes fresh perspectives on the interplay between band topology and electron-electron correlations in moiré superlattices.
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A recent experiment has reported the first observation of a zero-field fractional Chern insulator (FCI) phase in twisted bilayer MoTe_{2} moiré superlattices [J. Cai et al., Signatures of fractional quantum anomalous Hall states in twisted MoTe_{2}, Nature (London) 622, 63 (2023).NATUAS0028-083610.1038/s41586-023-06289-w]. The experimental observation is at an unexpected large twist angle 3.7° and calls for a better understanding of the FCI in real materials. In this Letter, we perform large-scale density functional theory calculation for the twisted bilayer MoTe_{2} and find that lattice reconstruction is crucial for the appearance of an isolated flat Chern band. The existence of the FCI state at ν=-2/3 is confirmed by exact diagonalization. We establish phase diagrams with respect to the twist angle and electron interaction, which reveal an optimal twist angle of 3.5° for the observation of FCI. We further demonstrate that an external electric field can destroy the FCI state by changing band geometry and show evidence of the ν=-3/5 FCI state in this system. Our research highlights the importance of accurate single-particle band structure in the quest for strong correlated electronic states and provides insights into engineering fractional Chern insulator in moiré superlattices.
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BACKGROUND: Allopolyploid breeding is an efficient technique for improving the low seed setting rate of autotetraploids in plant breeding and one of the most promising breeding methods. However, there have been few comprehensive studies of the posttranscriptional mechanism in allopolyploids. RESULTS: By crossing cultivated rice (Oryza sativa, genome AA) with wild rice (Oryza punctata, genome BB), we created hybrid rice lines with different ploidy and genome compositions [diploid hybrid F01 (AB), allotetraploid hybrid F02 (AABB) and F03 (AAAB)]. The genetic differences of the hybrids and the mechanism of allopolyploid breeding dominance were revealed through morphological and cytological observations and single molecule real-time sequencing techniques. The tissues and organs of allotetraploid hybrid F02 exhibited "gigantism" and the highest levels of fertility. The numbers of non-redundant transcripts, gene loci and new isoforms in the polyploid rice lines were higher and the isoform lengths greater than those of the diploid line. Moreover, alternative splicing (AS) events occurred twice as often in the polyploid rice lines than the diploid line. During these events, intron retention dominated. Furthermore, a large number of new genes and isoforms specific to the lines of different ploidy were discovered. CONCLUSIONS: The results indicated that alternative polyadenylation (APA) and AS events contributed to the complexity and superiority of polyploids in the activity of translation regulators, nucleic acid binding transcription factor activities and the regulation of molecular function. Therefore, these APA and AS events in allopolyploid rice were found to play a role in regulation. Our study provides new germplasm for polyploid rice breeding and reveals complex regulatory mechanisms that may be related to heterosis and fertility.
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Processamento Alternativo , Quimera/genética , Oryza/genética , Poliploidia , Processamento Pós-Transcricional do RNA , China , Produtos Agrícolas/genética , Variação Genética , Genoma de Planta , Genótipo , TranscriptomaRESUMO
Plant 14-3-3 proteins are phosphoserine-binding proteins that regulate a wide array of targets via direct protein-protein interactions. In this study, the role of a 14-3-3 protein, GRF9, in plant response to water stress was investigated. Arabidopsis wild-type, GRF9-deficient mutant (grf9), and GRF9-overexpressing (OE) plants were treated with polyethylene glycol (PEG) to induce mild water stress. OE plant showed better whole-plant growth and root growth than the wild type under normal or water stress conditions while the grf9 mutant showed worse growth. In OE plants, GRF9 favours the allocation of shoot carbon to roots. In addition, GRF9 enhanced proton extrusion, mainly in the root elongation zone and root hair zone, and maintained root growth under mild water stress. Grafting among the wild type, OE, and grf9 plants showed that when OE plants were used as the scion and GRF9 was overexpressed in the shoot, it enhanced sucrose transport into the root, and when OE plants were used as rootstock and GRF9 was overexpressed in the root, it caused more release of protons into the root surface under water stress. Taken together, the results suggest that under PEG-induced water stress, GRF9 is involved in allocating more carbon from the shoot to the root and enhancing proton secretion in the root growing zone, and this process is important for root response to mild water stress.
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Proteínas 14-3-3/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/fisiologia , Raízes de Plantas/crescimento & desenvolvimento , Polietilenoglicóis/farmacologia , Arabidopsis/efeitos dos fármacos , Arabidopsis/enzimologia , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Transporte Biológico/efeitos dos fármacos , Biomassa , Metabolismo dos Carboidratos/efeitos dos fármacos , Desidratação , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Glucosiltransferases/metabolismo , Floema/efeitos dos fármacos , Floema/metabolismo , Raízes de Plantas/anatomia & histologia , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas , ATPases Translocadoras de Prótons/metabolismo , Prótons , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Sintase do Amido/metabolismo , Sacarose/metabolismoRESUMO
Background: Chinese herbal medicine (CHM) has the advantage of being safe and effective and has been widely used in clinical practice for the treatment of type 2 diabetes mellitus (T2DM) with hyperuricemia (HUA), but its overall efficacy and safety remain unclear. This study aimed to evaluate the efficacy and safety of CHM for the treatment of T2DM with HUA based on randomized controlled trials (RCTs) to provide clinical evidence. Methods: The protocol evaluated in this study is registered with PROSPERO (CRD42022351519). As of November 2022, eight databases were searched, and RCTs of CHM for the treatment of T2DM with HUA were included. Outcome indicators observed included fasting blood glucose (FBG), 2-h postprandial glucose (2hPG), glycated hemoglobin (HbA1c), uric acid (UA), triglycerides (TG), total cholesterol (TC), overall effectiveness, and adverse events. Utilizing Review Manager 5.4, Stata V14.0, and GRADEpro, the included studies were evaluated, and the quality of the evidence was determined. Results: 18 RCTs covering 1,311 patients were included in this study. The results of the study demonstrated that the combination of CHM and western medicine (WM) was more effective in treating patients with T2DM with HUA than WM alone, with significant improvements in FBG (weighted mean differences (WMD) = -0.60.95% confidence interval (CI) [-0.81, -0.40], p < 0.00001), 2hPG (WMD = -1.12.95% CI [-1.64, -0.60], p < 0.0001), HbA1c (WMD = -0.80.95% CI [-1.04, -0.56], p < 0.00001), UA (WMD = -53.47.95% CI [-67.45, -39.48], p < 0.00001), TG (WMD = -0.56.95% CI [-0.74, -0.38], p < 0.00001), TC (WMD = -0.49.95% CI [-0.65, -0.33], p < 0.00001), and overall effective rate (risk ratio (RR) = 1.29.95%CI [1.13, 1.48], p = 0.0002). The quality of evidence for all outcomes was low. Conclusion: Compared with WM alone, the combination of CHM and WM was more effective in treating patients with T2DM with HUA, with significant improvements in glucose metabolism, uric acid, and lipids. However, further evaluation by high-quality RCT results is needed due to the low quality and high heterogeneity of the evidence. Systematic Review Registration: [https://systematicreview.gov/], identifier [CRD42022351519].
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Schizophrenia is a complex multi-factor neurological disorder that caused an array of severe indelible consequences to the individuals and society. Additionally, anti-schizophrenic drugs are unsuitable for treating negative symptoms and have more significant side effects and drug resistance. For better treatment and prevention, we consider exploring the pathogenesis of schizophrenia from other perspectives. A growing body of evidence of 22q11.2 deletion syndrome (22q11DS) suggested that the occurrence and progression of schizophrenia are related to mitochondrial dysfunction. So combing through the literature of 22q11DS published from 2000 to 2023, this paper reviews the mechanism of schizophrenia based on mitochondrial dysfunction, and it focuses on the natural drugs targeting mitochondria to enhance mitochondrial function, which are potential to improve the current treatment of schizophrenia.
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Síndrome de DiGeorge , Esquizofrenia , Humanos , Síndrome de DiGeorge/patologia , Mitocôndrias/patologiaRESUMO
Introduction: Anal fistula is one of the commonest ailments seen by anorectal surgeons as surgery is currently the preferred treatment for it. Diabetes mellitus is a risk factor that can lead to slow wound healing after anal fistula surgery. Because of the large postoperative wound surface of anal fistula, patients with diabetes can have an increased probability of wound infection, which makes it hard to heal. There is an extensive clinical experience for wound healing in traditional Chinese medicine (TCM). The Jiedu Shengji decoction (JSD) is a widely used external washing decoction in clinical practice. However, the current evidence on it is still insufficient. Therefore, we report this carefully designed clinical trial to assess the efficacy and safety of JSD in the treatment of postoperative wounds in diabetic patients with anal fistula. Methods and analysis: This study was designed to be a randomized, double-blind, placebo-controlled, multi-center clinical trial. There were 60 eligible participants who were randomized at a 1:1 ratio to the intervention and placebo groups. Both groups received the same standard treatment. The intervention group was given external washing decoction of TCM (JSD), while the placebo group was given the placebo made of excipients and flavoring agents. The main outcome measures include wound healing, distribution of wound pathogens, levels of inflammatory mediators, and blood glucose. The secondary outcome measures included lipids, the quality of the life evaluation scale (Short-Form Health Survey 36). Assessments were performed before the start of the study, at 1st, 2nd, 3rd, and 4th weeks after the intervention, and at 8th, 12th, and 16th follow-up weeks. Discussion: The clinical study we proposed will be the first randomized, double-blind, placebo-controlled, multi-center clinical trial study to assess the efficacy and safety of TCM external washing (JSD) in the treatment of postoperative wounds in diabetic patients with anal fistula. Ethics and dissemination: The Medical Ethics Committee of Hospital of Chengdu University of Traditional Chinese Medicine has reviewed this study protocol and gave its approval and consent on 17 March, 2022 (Ethical Review Number: 2022KL-018).
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Plant polyploidization is frequently associated with changes in nutrient contents. However, the possible contribution of metabolites to this change has not been investigated by characterizing the metabolite contents of diploid and tetraploid forms of rice (Oryza sativa L.). We compared the metabolites of a group of diploid-tetraploid japonica brown rice and a group of diploid-tetraploid indica brown rice based on liquid chromatography-tandem mass spectrometry. In total, 401 metabolites were identified; of these, between the two diploid-tetraploid groups, 180 showed opposite expression trends, but 221 showed the same trends (147 higher abundance vs. 74 lower abundance). Hierarchical cluster analysis of differential metabolites between diploid and tetraploid species showed a clear grouping pattern, in which the expression abundance of lipids, amino acids and derivatives, and phenolic acids increased in tetraploids. Further analysis revealed that the lipids in tetraploid rice increased significantly, especially unsaturated fatty acids and phospholipids. This study provides further basis for understanding the changes in rice nutritional quality following polyploidization and may serve as a new theoretical reference for breeding eutrophic or functional rice varieties via polyploidization.
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Microplastics have the characteristics of small size, high specific area, strong ability to adsorb pollutants, and difficult to degrade. They have become a major global environmental problem that humans urgently need to address. A balanced microecosystem is essential to human health. Animal studies have shown that long-term exposure to microplastics can change the characteristics of the microbiota in organisms, leading to respiratory, digestive, immune, and other system diseases. However, the current research on microplastics is still dominated by animal experiments, and the impact of microplastics on human health is still in its infancy, so relevant research is urgently needed. Twenty participants with high exposure to microplastics will come from a plastic factory in Chengdu, China. We will perform 16S rDNA sequencing on participants' nasal secretions, and stool samples. Additionally, we will perform 8700 LDIR laser infrared imaging of environmental soil and air filter membrane samples. For comparison, we will also collect samples from 20 volunteers from an area with good environmental quality in Chengdu. To find out the potential predictors and to access the difference between the groups, statistical analysis will be performed in the end. The study will be the first observational cross-sectional study focusing on the effects of microplastics on nasal and gut microbiota of high-exposure population. The study is expected to provide reliable evidence to fill the gaps in the impact of microplastics on human health.
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Poluentes Ambientais , Microbioma Gastrointestinal , Poluentes Químicos da Água , Animais , Estudos Transversais , Monitoramento Ambiental , Poluentes Ambientais/análise , Humanos , Microplásticos , Estudos Observacionais como Assunto , Plásticos/análise , Plásticos/farmacologia , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/farmacologiaRESUMO
Background: Microplastic has become a growing environmental problem. A balanced microbial environment is an important factor in human health. This study is the first observational cross-sectional study focusing on the effects of microplastics on the nasal and gut microbiota in a highly exposed population. Methods: We recruited 20 subjects from a Plastic Factory (microplastics high-exposure area) and the other 20 from Huanhuaxi Park (microplastics low-exposure area) in Chengdu, China. We performed the microplastic analysis of soil, air, and intestinal secretions by laser infrared imaging, and microbiological analysis of nasal and intestinal secretions by 16S rDNA sequencing. Results: The result shows that the detected points of microplastics in the environment of the high-exposure area were significantly more than in the low-exposure area. Polyurethane was the main microplastic component detected. The microplastic content of intestinal secretions in the high-exposure group was significantly higher than in the low-exposure group. Specifically, the contents of polyurethane, silicone resin, ethylene-vinyl acetate copolymer, and polyethylene in the high-exposure group were significantly higher than in the low-exposure group. Moreover, high exposure may increase the abundance of nasal microbiotas, which are positively associated with respiratory tract diseases, such as Klebsiella and Helicobacter, and reduce the abundance of those beneficial ones, such as Bacteroides. Simultaneously, it may increase the abundance of intestinal microbiotas, which are positively associated with digestive tract diseases, such as Bifidobacterium, Streptococcus, and Sphingomonas, and reduce the abundance of intestinal microbiotas, which are beneficial for health, such as Ruminococcus Torquesgroup, Dorea, Fusobacterium, and Coprococcus. A combined analysis revealed that high exposure to microplastics may not only lead to alterations in dominant intestinal and nasal microbiotas but also change the symbiotic relationship between intestinal and nasal microbiotas. Conclusion: The results innovatively revealed how microplastics can affect the intestinal and nasal microecosystems. Clinical trial registration: ChiCTR2100049480 on August 2, 2021.
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Microbioma Gastrointestinal , Microplásticos , Humanos , Plásticos/farmacologia , Poliuretanos/farmacologia , Estudos TransversaisRESUMO
Diabetes mellitus (DM) is a chronic noninfectious disease that is mainly featured by pancreatic ß-cell (ß-cell) dysfunction and impaired glucose homeostasis. Currently, the pathogenesis of dysfunction of the ß-cells in DM remains unclear, and therapeutic approaches to it are limited. Emodin (EMD), a natural anthraquinone derivative, has been preliminarily proven to show antidiabetic effects. However, the underlying mechanism of EMD on ß-cells still needs to be elucidated. In this study, we investigated the protective effects of EMD on the high glucose (50 mM)-induced INS-1 cell line and the underlying mechanism. INS-1 cells were treated with EMD (5, 10, and 20 µM) when exposed to high glucose. The effects of EMD were examined by using the inverted phase-contrast microscope, qRT-PCR, ELISA, and western blot. The results showed that EMD could alleviate cellular morphological changes, suppress IL-1ß and LDH release, and promote insulin secretion in high-glucose-induced INS-1 cells. Furthermore, EMD inhibits NOD-like receptor protein 3 (NLRP3) activation and gasdermin D (GSDMD) cleavage to alleviate pyroptosis induced by high glucose. Overexpression of NLRP3 reversed the above changes caused by EMD. Collectively, our findings suggest that EMD attenuates high-glucose-induced ß-cell pyroptosis by inhibiting NLRP3/GSDMD signaling.
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The gut microbiota (GM) and metabolites are important factors in mediating the development of type-2 diabetes mellitus (T2DM). An imbalance in the gut microbiota and metabolites can disrupt the function of the intestinal barrier, cause changes in the permeability of the intestinal mucosa and promote the immune inflammatory response, thereby aggravating the fluctuation of blood glucose level and promoting the occurrence and development of the chronic complications of DM. Manipulating the GM and metabolites is a promising therapeutic intervention and is being studied extensively. Shenqi compound (SQC) is a traditional Chinese medicine formulation, which has been widely used to improve T2DM. Studies have demonstrated that SQC can reduce glycemic variability, alleviate the inflammatory response, etc. However, its underlying mechanism remains unknown. Therefore, in this experiment, We administered SQC to Goto-Kakizaki (GK) rats and evaluated its effect on blood glucose homeostasis and the intestinal mucosal barrier. We identified the profiles of the GM and metabolites with the aid of 16S rDNA gene sequencing and non-target metabolomics analysis. It showed that SQC intervention could reduce glycemic variability, regulate serum levels of glucagon and insulin, and improve injury to the intestinal mucosal barrier of GK rats. In the gut, the ratio of bacteria of the phyla Bacteroidetes/Firmicutes could be improved after SQC intervention. SQC also regulated the relative abundance of Prevotellaceae, Butyricimonas, Bacteroides, Blautia, Roseburia, Lactobacillus, and Rothia. We found out that expression of 40 metabolites was significantly improved after SQC intervention. Further analyses of metabolic pathways indicated that the therapeutic effect of SQC might be related predominantly to its ability to improve gluconeogenesis/glycolysis, amino acid metabolism, lipid metabolism, citrate cycle, and butanoate metabolism. These results suggest that SQC may exert a beneficial role in T2DM by modulating the GM and metabolites in different pathways.
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Glicemia/metabolismo , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/microbiologia , Medicamentos de Ervas Chinesas/administração & dosagem , Microbioma Gastrointestinal/efeitos dos fármacos , Aminoácidos/metabolismo , Animais , Bactérias/classificação , Bactérias/efeitos dos fármacos , Bactérias/genética , Bactérias/isolamento & purificação , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/fisiopatologia , Gluconeogênese/efeitos dos fármacos , Glicólise/efeitos dos fármacos , Humanos , Insulina/sangue , Masculino , Ratos , Ratos WistarRESUMO
BACKGROUND: Rice is not only an essential food but also a source of high quality protein. Polyploidy is an evolutionary trajectory in plants, and enhancing glutelin by polyploidization is an attractive strategy for improving the nutritional value of rice seeds and presents a great potential for enhancing the commercial value of rice. Elucidating the mechanisms underlying glutelin synthesis and accumulation in tetraploid rice is of great significance. RESULTS: To enhance the nutritional value of rice, we developed tetraploid rice and evaluated the contents of various nutrient elements in mature seeds. The results revealed a significant increase in protein contents, including the total seed storage proteins, glutelins, and amino acids in tetraploid rice when compared with those in diploid rice. Tandem mass tag-based quantitative proteomic analyses of seeds revealed that glutelins regulated by several glutelin genes in 9311-4x were significantly up-regulated (≥1.5-fold), which was further verified by immunoblot analyses. In addition, temporal expression patterns of various glutelin subunits in different rice lines were investigated. The results revealed significant differences in the expression patterns between diploid and tetraploid rice seeds. Cytohistological analyses results revealed that the thickness of aleurone cell layers increased significantly by 32% in tetraploid rice, the structures of protein storage vacuoles (PSVs) in sub-aleurone cells were more diverse and abundant than those of diploid rice. Temporal expression and proteomic analyses results revealed that protein disulfide isomerase-like 1-1 expression levels were higher in tetraploid rice than in diploid rice, and that the gene responded to oxidative folding with increased levels of proglutelin and appropriate distribution of seed glutelins in tetraploid rice. CONCLUSION: The results of the present study revealed that polyploidization increased glutelin content by influencing glutelin biosynthesis, transport, and deposition, while variations in glutelin accumulation between tetraploid and diploid rice were largely manifested in the initial time, duration, and relative levels of various glutelin gene expressions during seed filling stages. These findings provide novel insights into improving the protein quality and nutritional value of rice seeds by polyploid breeding.
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The breeding of polyploid rice made no breakthrough for a long time because of low seed set. The discovery and application of polyploid meiosis stability (PMeS) material played a pivotal role in solving this problem. Our results indicated that genome duplication led to different outcomes in different rice cultivars in terms of pollen fertility, viability, and the accumulation of important physiological substances such as free proline and endogenous hormones. Pollen from the PMeS HN2026-4X lines showed a high fertility and viability similar to those of HN2026-2X (4X indicates tetraploid while 2X indicates the diploid), whereas both rates decreased dramatically in Balilla-4X. The results of pollen microstructure and ultrastructure investigations suggested that the pollen development pattern in HN2026-4X appeared normal at all stages, but a lot of changes were discovered in Balilla-4X. Stable meiosis, timely tapetum degradation, and normal mitochondria development were critical factors insuring the high frequency pollen fertility of PMeS rice. The free proline content increased markedly in HN2026-4X as compared to HN2026-2X, but it was decreased for Balilla-4X. Genome duplication effects on regulating endogenous hormones accumulation in pollen were evident, resulting in the clear difference between PMeS HN2026-4X and Balilla-4X. The accumulation of IAA, ZR, and GA in mature pollen distinguished HN2026-4X from Balilla-4X, which was linked to normal pollen development. In particular, the excessive accumulation of ABA at the meiosis stage may be correlated to disorganized meiosis in Balilla-4X. All the results provided unequivocal evidence that genome duplication played specific roles in the normal pollen development of PMeS HN2026-4X.
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Duplicação Gênica/genética , Meiose/genética , Oryza/crescimento & desenvolvimento , Oryza/genética , Pólen/crescimento & desenvolvimento , Poliploidia , Pólen/genéticaRESUMO
Seed of rice is an important strategic resource for ensuring the security of China's staple food. Seed deterioration as a result of senescence is a major problem during seed storage, which can cause major economic losses. Screening among accessions in rice germplasm resources for traits such as slow senescence and increased seed longevity during storage is, therefore, of great significance. However, studies on delayed senescence in rice have been based mostly on diploid rice seed to date. Despite better tolerance have been verified by the artificial aging treatment for polyploid rice seed, the delayed senescence properties and delayed senescence related regulatory mechanisms of polyploid rice seed are rarely reported, due to the lack of polyploid rice materials with high seed set. High-throughput sequencing was applied to systematically investigate variations in small RNAs, the degradome, and the proteome between tetraploid and diploid rice seeds. Degradome sequencing analysis of microRNAs showed that expression of miR-164d, which regulates genes encoding antioxidant enzymes, was changed significantly, resulting in decreased miRNA-mediated cleavage of target genes in tetraploid rice. Comparisons of the expression levels of small RNAs (sRNAs) in the tetraploid and diploid libraries revealed that 12 sRNAs changed significantly, consistent with the findings from degradome sequencing. Furthermore, proteomics also showed that antioxidant enzymes were up-regulated in tetraploid rice seeds, relative to diploids.
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Oryza/metabolismo , Proteômica , Estabilidade de RNA , Pequeno RNA não Traduzido/genética , Sementes/genética , Análise de Sequência de RNA , Tetraploidia , Oryza/genética , RNA de Plantas/química , RNA de Plantas/genética , Pequeno RNA não Traduzido/química , Integração de SistemasRESUMO
One-dimensional electronic systems can support exotic collective phases because of the enhanced role of electron correlations. We describe the experimental observation of a series of quantized conductance steps within strongly interacting electron waveguides formed at the lanthanum aluminate-strontium titanate (LaAlO3/SrTiO3) interface. The waveguide conductance follows a characteristic sequence within Pascal's triangle: (1, 3, 6, 10, 15, ) â e 2 /h, where e is the electron charge and h is the Planck constant. This behavior is consistent with the existence of a family of degenerate quantum liquids formed from bound states of n = 2, 3, 4, electrons. Our experimental setup could provide a setting for solid-state analogs of a wide range of composite fermionic phases.