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The unexpected discovery of hot Jupiters challenged the classical theory of planet formation inspired by our solar system. Until now, the origin and evolution of hot Jupiters are still uncertain. Determining their age distribution and temporal evolution can provide more clues into the mechanism of their formation and subsequent evolution. Using a sample of 383 giant planets around Sun-like stars collected from the kinematic catalogs of the Planets Across Space and Time project, we find that hot Jupiters are preferentially hosted by relatively younger stars in the Galactic thin disk. We subsequently find that the frequency of hot Jupiters declines with age as [Formula: see text]. In contrast, the frequency of warm/cold Jupiters shows no significant dependence on age. Such a trend is expected from the tidal evolution of hot Jupiters' orbits, and our result offers supporting evidence using a large sample. We also perform a joint analysis on the planet frequencies in the stellar age-metallicity plane. The result suggests that the frequencies of hot Jupiters and warm/cold Jupiters, after removing the age dependence are both correlated with stellar metallicities as [Formula: see text] and [Formula: see text], respectively. Moreover, we show that the above correlations can explain the bulk of the discrepancy in hot Jupiter frequencies inferred from the transit and radial velocity (RV) surveys, given that RV targets tend to be more metal-rich and younger than transits.
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NCOA4 is a selective cargo receptor for ferritinophagy, the autophagic turnover of ferritin (FTH), a process critical for regulating intracellular iron bioavailability. However, how ferritinophagy flux is controlled through NCOA4 in iron-dependent processes needs to be better understood. Here, we show that the C-terminal FTH-binding domain of NCOA4 harbors a [3Fe-4S]-binding site with a stoichiometry of approximately one labile [3Fe-4S] cluster per NCOA4 monomer. By analyzing the interaction between NCOA4 and HERC2 ubiquitin ligase or NCOA4 and FTH, we demonstrate that NCOA4 regulates ferritinophagy by sensing the intracellular iron-sulfur cluster levels. Under iron-repletion conditions, HERC2 recognizes and recruits holo-NCOA4 as a substrate for polyubiquitination and degradation, favoring ferritin iron storage. Under iron-depletion conditions, NCOA4 exists in the form of apo-protein and binds ferritin to promote the occurrence of ferritinophagy and release iron. Thus, we identify an iron-sulfur cluster [3Fe-4S] as a critical cofactor in determining the fate of NCOA4 in favoring iron storage in ferritin or iron release via ferritinophagy and provide a dual mechanism for selective interaction between HERC2 and [3Fe-4S]-NCOA4 for proteasomal degradation or between ferritin and apo-NCOA4 for ferritinophagy in the control of iron homeostasis.
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Homeostase , Ferro , Coativadores de Receptor Nuclear , Autofagia , Ferritinas/metabolismo , Ferro/química , Ferro/metabolismo , Coativadores de Receptor Nuclear/genética , Coativadores de Receptor Nuclear/metabolismo , Enxofre/química , Enxofre/metabolismo , Humanos , Animais , Camundongos , Domínios Proteicos , Linhagem Celular , Células Cultivadas , Ubiquitina-Proteína Ligases/metabolismo , Estabilidade Proteica , Complexo de Endopeptidases do Proteassoma/metabolismoRESUMO
Noncanonical peptides (NCPs) are a class of peptides generated from regions previously thought of as noncoding, such as introns, 5' UTRs, 3' UTRs, and intergenic regions. In recent years, the significance and diverse functions of NCPs have come to light, yet a systematic and comprehensive NCP database remains absent. Here, we developed NCPbook (https://ncp.wiki/ncpbook/), a database of evidence-supported NCPs, which aims to provide a resource for efficient exploration, analysis, and manipulation of NCPs. NCPbook incorporates data from diverse public databases and scientific literature. The current version of NCPbook includes 180,676 NCPs across 29 different species, evidenced by MS, ribosome profiling, or molecular experiments. These NCPs are distributed across kingdoms, comprising 123,408 from 14 plant species, 56,999 from 7 animal species, and 269 from 8 microbial species. Furthermore, NCPbook encompasses 9,166 functionally characterized NCPs playing important roles in immunity, stress resistance, growth, and development. Equipped with a user-friendly interface, NCPbook allows users to search, browse, visualize, and retrieve data, making it an indispensable platform for researching NCPs in various plant, animal, and microbial species.
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Peptídeos , Peptídeos/metabolismo , Animais , Plantas/metabolismo , Plantas/genética , Bases de Dados de ProteínasRESUMO
In Arabidopsis thaliana, the female gametophyte consists of two synergid cells, an egg cell, a diploid central cell, and three antipodal cells. CYTOKININ INDEPENDENT 1 (CKI1), a histidine kinase constitutively activating the cytokinin signaling pathway, specifies the central cell and restricts the egg cell. However, the mechanism regulating CKI1-dependent central cell specification is largely unknown. Here, we showed that the type-B ARABIDOPSIS RESPONSE REGULATORS10, 12, and 18 (ARR10/12/18) localize at the chalazal pole of the female gametophyte. Phenotypic analysis showed that the arr10 12 18 triple mutant is female sterile. We examined the expression patterns of embryo sac marker genes and found that the embryo sac of arr10 12 18 plants had lost central cell identity, a phenotype similar to that of the Arabidopsis cki1 mutant. Genetic analyses demonstrated that ARR10/12/18, CKI1, and ARABIDOPSIS HISTIDINE PHOSPHOTRANSFER PROTEIN2, 3, and 5 (AHP2/3/5) function in a common pathway to regulate female gametophyte development. In addition, constitutively activated ARR10/12/18 in the cki1 embryo sac partially restored the fertility of cki1. Results of transcriptomic analysis supported the conclusion that ARR10/12/18 and CKI1 function together to regulate the identity of the central cell. Our results demonstrated that ARR10/12/18 function downstream of CKI1-AHP2/3/5 as core factors to determine cell fate of the female gametophyte.
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Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Citocininas/metabolismo , Óvulo Vegetal/genética , Óvulo Vegetal/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
Organophosphate esters (OPEs) have been observed in the remote Arctic Ocean, yet the influence of hydrodynamics and seasonal sea ice variations on the occurrence and transport of waterborne OPEs remains unclear. This study comprehensively examines OPEs in surface seawater of the central Arctic Ocean during the summer of 2020, integrating surface ocean current and sea ice concentration data. The results confirm significant spatiotemporal variations of the OPEs, with the total concentration of seven major OPEs averaging 780 ± 970 pg/L. Chlorinated OPEs, particularly tris(1-chloro-2-propyl) phosphate (TCPP), were dominant. The significant impact of hydrodynamics on the OPE transport is demonstrated by higher OPE concentrations in regions with strong surface currents, especially at the edge of the Beaufort Gyre and the confluence of the Beaufort Gyre and the Transpolar Drift. Furthermore, OPE levels were generally higher in drifting-ice-covered regions compared to ice-free regions, attributed to the volatilization of dissolved OPEs formerly trapped below the sea ice or newly released from melting snow and sea ice. Notably, TCPP decreased by only 19% in the ice-free area, while the more volatile triphenyl phosphate decreased by 63% compared with the partial ice region.
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Ésteres , Camada de Gelo , Organofosfatos , Estações do Ano , Regiões Árticas , Camada de Gelo/química , Água do Mar/química , Oceanos e Mares , Poluentes Químicos da Água/análise , Monitoramento AmbientalRESUMO
Fufang Xiling Jiedu capsule (FXJC), a traditional Chinese medicine that evolved from "Yinqiao Powder", is widely used for the treatment of cold and influenza. However, due to a lack of in vivo metabolism research, the chemical components responsible for the therapeutic effects still remain unclear. Hence, this study aimed to describe the metabolic profiles of the FXJC in rat plasma, urine, and feces. A combined data mining strategy based on ultra-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry was employed and 201 xenobiotics, including 117 prototype components and 84 metabolites were detected. Phenolic acids, flavonoids, triterpenes, and lignans were prominent ingredients absorbed in vivo, and the major metabolic pathways of the detected metabolites were glucuronidation, sulfation, methylation, and oxidation. This is the first systematic study on the metabolism of the FXJC in vivo, providing valuable information for future studies on the efficacy, toxicity, and mechanism of the FXJC.
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Medicamentos de Ervas Chinesas , Espectrometria de Massas em Tandem , Ratos , Animais , Espectrometria de Massas em Tandem/métodos , Ratos Sprague-Dawley , Cromatografia Líquida de Alta Pressão/métodos , Administração Oral , Medicamentos de Ervas Chinesas/análise , MetabolomaRESUMO
OBJECTIVE: The objective of this study was to investigate the correlation between various factors and the clinical outcomes of Intrauterine Insemination (IUI) in both young and aged patients, aiming to provide a theoretical basis for clinical consultations. METHODS: This retrospective analysis examined a total of 4,221 IUI cycles conducted at the Reproductive Center of Changzhou Maternal and Child Health Hospital between January 2016 and December 2020. The patients were categorized into two groups based on age: the elder group (≥ 35 years) and the young group (< 35 years). RESULTS: The findings of this study revealed a significant association between woman's age and BMI with pregnancy outcomes (0.93, 95% CI: 0.89-0.97) (1.04, 95% CI: 1.01-1.06). Moreover, in young women, both age and Body Mass Index (BMI)were found to be related to pregnancy outcomes (0.97, 95% CI: 0.89-0.97) (1.08, 95% CI: 1.01-1.06). Additionally, BMI and the number of cycles in aged IUI patients were found to be associated with pregnancy outcomes. The pregnancy rate in the second cycle was approximately 1.9 times higher than that in the first cycle (1.9, 95% CI: 0.97-3.77), and in the third cycle, it was approximately 3 times higher than that in the first cycle (3.04, 95% CI: 1.43-6.42). CONCLUSIONS: In conclusion, there is an association between woman's age and BMI and the clinical outcomes of IUI. However, the number of cycles did not affect the pregnancy outcomes in young women. Conversely, in elder women, the number of cycles was found to be related to the IUI pregnancy outcomes, with significantly higher pregnancy rates observed in the second and third cycles compared to the first cycle.
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Fertilização in vitro , Resultado da Gravidez , Gravidez , Criança , Humanos , Feminino , Idoso , Adulto , Estudos Retrospectivos , Taxa de Gravidez , Inseminação Artificial , Indução da OvulaçãoRESUMO
BACKGROUND: This research delved into the association between the risk of the Chinese population suffering from breast cancer (BC) and the triglyceride-glucose (TyG) index. METHODS: A total of 2,111 sufferers with benign breast disease (BBD) and 477 sufferers with BC were enrolled, and their TyG index was measured. Participants with varying TyG index values were categorized into quartiles. Logistic regression analysis was employed to assess the relationship between the TyG index and BC risk. The diagnostic performance of the TyG index for different stages of BC was measured using the receiver operating characteristic (ROC) curve. RESULTS: The TyG index of BC sufferers exceeded that of BBD (P < 0.001). A continuous increase in the risk of BC was found to be positively correlated with an ever-increasing TyG index. In the unadjusted model, the risk of getting BC mounted with quartiles of the TyG index growing (P < 0.001). In a logistic regression analysis that included all confounders, the highest quartile of the TyG index was strongly linked to BC risk [1.43 (1.01, 2.02), P < 0.05]. Moreover, with the adjustment of potential confounders, a high TyG index was found to result in a 2.53-fold higher risk of being diagnosed with advanced BC. CONCLUSIONS: The risen TyG index was positively correlated to the heightening risk of BC and had the potential to serve as a promising biomarker for BC. Individuals with a high TyG index ought to be mindful of the heightened risk of BC onset and progression.
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Neoplasias da Mama , Humanos , Feminino , Estudos Transversais , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/epidemiologia , Fatores de Risco , China/epidemiologia , Glucose , Triglicerídeos , Glicemia , BiomarcadoresRESUMO
Concrete structures have emerged as some of the most extensively utilized materials in the construction industry due to their inherent plasticity and high-strength characteristics. However, due to the temperature fluctuations, humidity, and damage caused by human activities, challenges such as crack propagation and structural failures pose threats to the safety of people's lives and property. Meanwhile, conventional non-destructive testing methods are limited to defect detection and lack the capability to provide real-time monitoring and evaluating of concrete structural stability. Consequently, there is a growing emphasis on the development of effective techniques for monitoring the health of concrete structures, facilitating prompt repairs and mitigation of potential instabilities. This paper comprehensively presents traditional and novel methods for concrete structural properties and damage evolution monitoring, including emission techniques, electrical resistivity monitoring, electromagnetic radiation method, piezoelectric transducers, ultrasonic techniques, and the infrared thermography approach. Moreover, the fundamental principles, advantages, limitations, similarities and differences of each monitoring technique are extensively discussed, along with future research directions. Each method has its suitable monitoring scenarios, and in practical applications, several methods are often combined to achieve better monitoring results. The outcomes of this research provide valuable technical insights for future studies and advancements in the field of concrete structural health monitoring.
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AIM: To synthesize evidence regarding the effectiveness of technology-based psychosocial interventions in improving health-related outcomes among family caregivers of stroke survivors. DESIGN: A systematic review and meta-analysis was reported by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. METHODS: Randomized controlled trials that investigated the effects of psychosocial interventions delivered through information and communication technologies on self-efficacy, caregiving competence, caregiver burden, perceived social support, anxiety, depression, health-related quality of life and cost-effectiveness were included. Two researchers independently selected studies, extracted data, and appraised the quality of the included studies. Subgroup analysis, sensitivity analysis, and narrative synthesis were conducted. DATA SOURCES: Ten electronic databases (PubMed, CENTRAL, Web of Science, Scopus, CINHAL, Embase, Institution of Electrical Engineers Xplore, Ovid Medline, PsycINFO, ProQuest Dissertations and Thesis) were searched up to February 2023. RESULTS: Nineteen studies involving 1717 participants fulfilled the eligibility criteria. Technology-based psychosocial interventions significantly improved self-efficacy (SMD = .62), caregiving competence (SMD = .55), depression (SMD = -.25) and anxiety (SMD = -.35). However, perceived social support, caregiver burden, and health-related quality of life did not show significant improvements. Subgroup analyses revealed that the interventions, lasting from 4 to 6 weeks and encompassing comprehensive contents, exhibited larger effect sizes. None of the studies measured cost-effectiveness. CONCLUSION: The technology-based psychosocial interventions are effective in enhancing self-efficacy and caregiving competence, as well as alleviating anxiety, and depression among family caregivers of stroke survivors. Future research should investigate interventions delivered through various digital platforms using well-designed RCTs with in-depth qualitative data collection and measurement of health and cost-effectiveness outcomes. IMPACT: Through psychosocial interventions, healthcare providers in clinical and community settings, particularly nurses, could incorporate technologies into current stroke care practices. PATIENT OR PUBLIC CONTRIBUTION: It is not applicable as this is a systematic review. REGISTRATION: The protocol was registered on PROSPERO (CRD42023402871).
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Cuidadores , Humanos , Cuidadores/psicologia , Acidente Vascular Cerebral/psicologia , Acidente Vascular Cerebral/enfermagem , Intervenção Psicossocial/métodos , Qualidade de Vida/psicologia , Sobreviventes/psicologia , Apoio Social , Ansiedade/psicologia , Feminino , Ensaios Clínicos Controlados Aleatórios como Assunto , Masculino , Autoeficácia , Depressão/psicologiaRESUMO
With global warming, drought stress is becoming increasingly severe, causing serious impacts on crop yield and quality. In order to survive under adverse conditions such as drought stress, plants have evolved a certain mechanism to cope. The tolerance to drought stress is mainly improved through the synergistic effect of regulatory pathways, such as transcription factors, phytohormone, stomatal movement, osmotic substances, sRNA, and antioxidant systems. This study summarizes the research progress on plant drought resistance, in order to provide a reference for improving plant drought resistance and cultivating drought-resistant varieties through genetic engineering technology.
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Secas , Estresse Fisiológico , Regulação da Expressão Gênica de Plantas , Plantas/metabolismo , Plantas/genética , Reguladores de Crescimento de Plantas/metabolismo , Fenômenos Fisiológicos VegetaisRESUMO
BACKGROUND: Postmenopausal osteoporosis (PMO) is associated with dysregulation of bone metabolism and gut microbiota. Quinoa is a grain with high nutritional value, and its effects and potential mechanisms on PMO have not been reported yet. Therefore, the purpose of this study is to investigate the bone protective effect of quinoa on ovariectomy (OVX) rats by regulating bone metabolism and gut microbiota. RESULTS: Quinoa significantly improved osteoporosis-related biochemical parameters of OVX rats and ameliorated ovariectomy-induced bone density reduction and trabecular structure damage. Quinoa intervention may repair the intestinal barrier by upregulating the expression of tight junction proteins in the duodenum. In addition, quinoa increased the levels of Firmicutes, and decreased the levels of Bacteroidetes and Prevotella, reversing the dysregulation of the gut microbiota. This may be related to estrogen signaling pathway, secondary and primary bile acid biosynthesis, benzoate degradation, synthesis and degradation of ketone bodies, NOD-like receptor signaling pathway and biosynthesis of tropane, piperidine and pyridine alkaloids. Correlation analysis showed that there is a strong correlation between gut microbiota with significant changes in abundance and parameters related to osteoporosis. CONCLUSION: Quinoa could significantly reverse the high intestinal permeability and change the composition of gut microbiota in OVX rats, thereby improving bone microstructure deterioration and bone metabolism disorder, and ultimately protecting the bone loss of OVX rats. © 2024 Society of Chemical Industry.
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Densidade Óssea , Chenopodium quinoa , Microbioma Gastrointestinal , Ovariectomia , Ratos Sprague-Dawley , Animais , Ratos , Feminino , Chenopodium quinoa/química , Densidade Óssea/efeitos dos fármacos , Humanos , Bactérias/classificação , Bactérias/metabolismo , Bactérias/isolamento & purificação , Bactérias/genética , Osteoporose/metabolismo , Osteoporose/prevenção & controle , Osteoporose Pós-Menopausa/metabolismo , Osteoporose Pós-Menopausa/prevenção & controle , Osteoporose Pós-Menopausa/microbiologiaRESUMO
Bis-(10-deoxydihydroartemisinin)-phloroglucinol (9), has been synthesized in a one-step reaction and has demonstrated strong inhibition to cancer cell proliferation and immunosuppressive activity. The structure modification of the compound reduced its cytotoxicity, and among the analogs, bis-(10-deoxydihydroartemisinin)-phloroglucinol phenyl decanoate (16) showed significant reduction of ear swelling in a mouse model for DNFB-induced delayed-type hypersensitivity without observable toxicity in a dose-dependent manner.
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Antineoplásicos , Artemisininas , Camundongos , Animais , Relação Estrutura-Atividade , Floroglucinol , Artemisininas/química , Imunossupressores/farmacologia , Proliferação de Células , Antineoplásicos/químicaRESUMO
OBJECTIVES: To evaluate the effectiveness of combined aerobic and resistance exercise on cognition, metabolic health, physical function, and health-related quality of life (HRQoL) in middle-aged and older adults with type 2 diabetes mellitus (T2DM). DATA SOURCE AND STUDY SELECTION: Systematic search of CINAHL, Cochrane, EMBASE, Scopus, PubMed, ProQuest Dissertation and Thesis, PsycINFO, Web of Science databases, and gray literature from Google Scholar. Pertinent randomized controlled trials (RCTs) were selected. The Protocol was registered in the International Prospective Register of Systematic Reviews (PROSPERO CRD42023387336). DATA EXTRACTION: The risk of bias was evaluated using the Cochrane Risk of Bias tool by 2 reviewers independently. Outcome data were extracted in a fixed-effect model if heterogeneity test were not significant and I2≤50%; otherwise, the random-effects model was used. DATA SYNTHESIS: Sixteen studies with 2426 participants were included in this review. Combined aerobic and resistance exercise had significant positive effects on cognition (SMD=0.34, 95% CI: 0.13 to 0.55), metabolic health on HbA1c (SMD=-0.35, 95% CI: -0.48 to -0.22) and lipid profile (total cholesterol SMD=-0.20, 95% CI: -0.34 to -0.07; low-density lipoprotein SMD=-0.19, 95% CI: -0.33 to -0.05; high-density lipoprotein SMD=0.25, 95% CI: 0.12 to 0.39; and triglycerides SMD=-0.18, 95% CI: -0.31 to -0.04), physical function on aerobic oxygen uptake (SMD=0.58, 95% CI: 0.21 to 0.95) and body mass index (MD=-1.33, 95% CI: -1.84 to -0.82), and physical HRQoL (MD=4.17, 95% CI: 0.86 to 7.48). Our results showed that clinically important effects on cognition may occur in combining the low-moderate intensity of aerobic exercise and progressive intensity of resistance training, the total duration of the exercise needs to be at least 135 minutes per week, among which, resistance training should be at least 60 minutes. CONCLUSION: Combined aerobic and resistance exercise effectively improves cognition, ameliorates metabolic health, enhances physical function, and increases physical HRQoL in middle-aged and older adults with T2DM. More RCTs and longitudinal follow-ups are required to provide future evidence of structured combined aerobic and resistance exercise on other domains of cognition.
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Cadmium (Cd) is a major environmental pollutant and poses a risk of transfer into the food chain through contaminated plants. Mechanisms underlying Cd tolerance and hyperaccumulation in plants are not fully understood. Proteomics-based approaches facilitate an in-depth understanding of plant responses to Cd stress at the systemic level by identifying Cd-inducible differentially abundant proteins (DAPs). In this review, we summarize studies related to proteomic changes associated with Cd-tolerance mechanisms in Cd-tolerant crops and Cd-hyperaccumulating plants, especially the similarities and differences across plant species. The enhanced DAPs identified through proteomic studies can be potential targets for developing Cd-hyperaccumulators to remediate Cd-contaminated environments and Cd-tolerant crops with low Cd content in the edible organs. This is of great significance for ensuring the food security of an exponentially growing global population. Finally, we discuss the methodological drawbacks in current proteomic studies and propose that better protocols and advanced techniques should be utilized to further strengthen the reliability and applicability of future Cd-stress-related studies in plants. This review provides insights into the improvement of phytoremediation efficiency and an in-depth study of the molecular mechanisms of Cd enrichment in plants.
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Cádmio , Poluentes do Solo , Cádmio/metabolismo , Biodegradação Ambiental , Proteômica , Reprodutibilidade dos Testes , Poluentes do Solo/metabolismo , Produtos Agrícolas/metabolismoRESUMO
The size of seeds is particularly important for agricultural development, as it is a key trait that determines yield. It is controlled by the coordinated development of the integument, endosperm, and embryo. Large seeds are an important way of improving the ultimate "sink strength" of crops, providing more nutrients for early plant growth and showing certain tolerance to abiotic stresses. There are several pathways for regulating plant seed size, including the HAIKU (IKU) pathway, ubiquitin-proteasome pathway, G (Guanosine triphosphate) protein regulatory pathway, mitogen-activated protein kinase (MAPK) pathway, transcriptional regulators pathway, and phytohormone regulatory pathways including the auxin, brassinosteroid (BR), gibberellin (GA), jasmonic acid (JA), cytokinin (CK), Abscisic acid (ABA), and microRNA (miRNA) regulatory pathways. This article summarizes the seed size regulatory network and prospective ways of improving yield. We expect that it will provide a valuable reference to researchers in related fields.
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Reguladores de Crescimento de Plantas , Sementes , Sementes/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Ácido Abscísico/metabolismo , Endosperma/metabolismo , Giberelinas/metabolismo , Regulação da Expressão Gênica de PlantasRESUMO
Maize accumulates large amounts of starch in seeds which have been used as food for human and animals. Maize starch is an importantly industrial raw material for bioethanol production. One critical step in bioethanol production is degrading starch to oligosaccharides and glucose by α-amylase and glucoamylase. This step usually requires high temperature and additional equipment, leading to an increased production cost. Currently, there remains a lack of specially designed maize cultivars with optimized starch (amylose and amylopectin) compositions for bioethanol production. We discussed the features of starch granules suitable for efficient enzymatic digestion. Thus far, great advances have been made in molecular characterization of the key proteins involved in starch metabolism in maize seeds. The review explores how these proteins affect starch metabolism pathway, especially in controlling the composition, size and features of starch. We highlight the roles of key enzymes in controlling amylose/amylopectin ratio and granules architecture. Based on current technological process of bioethanol production using maize starch, we propose that several key enzymes can be modified in abundance or activities via genetic engineering to synthesize easily degraded starch granules in maize seeds. The review provides a clue for developing special maize cultivars as raw material in the bioethanol industry.
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Amilose , Biocombustíveis , Etanol , Amido , Zea mays , Humanos , Amilopectina/metabolismo , Amilose/metabolismo , Engenharia Genética , Sementes/metabolismo , Amido/biossíntese , Amido/genética , Zea mays/genética , Zea mays/metabolismoRESUMO
BACKGROUND: Currently, mechanical maize kernel harvesting has not been fully utilized in developing countries including China, partly due to the absence of suitable cultivars capable of rapid desiccation during seed maturation. The initiation of rapid desiccation during seed maturation is regulated by abscisic acid (ABA). For further characterization of ABA-regulated key genes and cellular events, it is necessary to perform transcriptome analysis of maize developing embryos. The ABA synthesis-deficient mutant (vp5) and normal maize (Vp5) seeds are suitable materials for such purpose. RESULTS: In the present work, developing vp5 and Vp5 embryos were compared by ABA content and transcriptome analyses. Quantitative analysis revealed the significant difference in ABA synthesis between both genotypes. From 29 days after pollination (DAP), ABA content increased rapidly in Vp5 embryos, but decreased gradually in vp5 embryos. At 36 DAP, ABA level in vp5 decreased to 1/4 that of Vp5, suggesting that the differential ABA levels would affect seed maturation. Comparative transcriptomic analysis has found 1019 differentially expressed genes (DEGs) between both genotypes, with the most DEGs (818) at 36 DAP. Further, weighted correlation network analysis (WGCNA) revealed eight DEGs co-expression modules. Particularly, a module was negatively correlated with ABA content in vp5 embryos. The module was mainly involved in metabolic and cellular processes, and its hub genes encoded thiamine, NPF proteins, calmodulin, metallothionein etc. Moreover, the expression of a set of key genes regulated by ABA was further verified by RT-qPCR. The results of the present work suggested that because of ABA deficiency, the vp5 seeds maintained strong metabolic activities and lacked dormancy initiation during seed maturation. CONCLUSION: Transcriptome and WGCNA analyses revealed significant ABA-related changes in metabolic pathways and DEGs between vp5 and Vp5 during seed maturation. The results would provide insights for elucidating the molecular mechanism of ABA signaling and developing high dehydration tolerance maize suitable for mechanical harvesting.
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Ácido Abscísico , Zea mays , Ácido Abscísico/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Sementes/genética , Sementes/metabolismo , Transcriptoma , Zea mays/genética , Zea mays/metabolismoRESUMO
Colorectal cancer (CRC) is the leading deadly cancer worldwide. Gene associated with retinoid-IFN-induced mortality-19 (GRIM-19), a novel tumor suppressor, has been reported to be expressed at low levels in human CRC. However, the role of GRIM-19 in CRC progression and the corresponding detailed mechanisms are unclear. The results of this study indicated that GRIM-19 expression is related to CRC progression. Overexpression of GRIM-19 was found to inhibit CRC cell proliferation and induce apoptosis in vitro and in vivo. Our results demonstrated that GRIM-19 suppresses CRC through posttranslational regulation of p53, in which SIRT7 is activated by GRIM-19 and triggers PCAF-mediated MDM2 ubiquitination, eventually stabilizing the p53 protein. We also observed that GRIM-19 enhances the effect of oxaliplatin against CRC. In conclusion, GRIM-19 plays an important role in CRC development and is a potential biomarker and therapeutic target for clinical treatment of CRC.
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Proteínas Reguladoras de Apoptose/metabolismo , Apoptose/fisiologia , Proliferação de Células/fisiologia , Neoplasias Colorretais/metabolismo , NADH NADPH Oxirredutases/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Linhagem Celular Tumoral , Neoplasias Colorretais/patologia , Regulação Neoplásica da Expressão Gênica/fisiologia , Genes Supressores de Tumor/fisiologia , Humanos , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Sirtuínas/metabolismo , Ubiquitinação/fisiologiaRESUMO
OBJECTIVES: The study aimed to explore the key points of computed tomography (CT) differential diagnosis of nontuberculous mycobacteria (NTM) and secondary pulmonary tuberculosis in elderly patients. METHODS: We retrospectively analyzed 45 patients with NTM pulmonary disease and 65 patients with secondary pulmonary tuberculosis. All patients were older than 60 years. The diseases were confirmed by laboratory examination. The general data and CT images of the 2 groups were compared and analyzed using χ 2 tests, single-factor analysis, and multivariate logistic regression analysis. RESULTS: Single-factor analysis showed significant differences between the 2 groups in 9 factors: bronchiectasis of the left upper lobe lingual segment, bronchiectasis of the right middle lobe, small nodules, large nodules, thin-walled cavities, thick-walled cavities, nonsubpleural hollows, strip opacity, and mediastinal lymph node enlargement ( P < 0.05). Multivariate logistic regression analysis showed that thin-walled cavities, bronchiectasis of the right middle lobe, small nodules, and large nodules were important factors in the differential diagnosis of the two groups. CONCLUSIONS: Nontuberculous mycobacteria show certain characteristics on CT, which are helpful for differential diagnosis when coupled with clinical and sputum smear examinations.