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The brain is constituted of heterogeneous types of neuronal and non-neuronal cells, which are organized into distinct anatomical regions, and show precise regulation of gene expression during development, aging and function. In the current database release, STAB2 provides a systematic cellular map of the human and mouse brain by integrating recently published large-scale single-cell and single-nucleus RNA-sequencing datasets from diverse regions and across lifespan. We applied a hierarchical strategy of unsupervised clustering on the integrated single-cell transcriptomic datasets to precisely annotate the cell types and subtypes in the human and mouse brain. Currently, STAB2 includes 71 and 61 different cell subtypes defined in the human and mouse brain, respectively. It covers 63 subregions and 15 developmental stages of human brain, and 38 subregions and 30 developmental stages of mouse brain, generating a comprehensive atlas for exploring spatiotemporal transcriptomic dynamics in the mammalian brain. We also augmented web interfaces for querying and visualizing the gene expression in specific cell types. STAB2 is freely available at https://mai.fudan.edu.cn/stab2.
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Encéfalo , Bases de Dados Genéticas , Neurônios , Análise da Expressão Gênica de Célula Única , Animais , Humanos , Camundongos , Atlas como Assunto , Encéfalo/citologia , Encéfalo/crescimento & desenvolvimento , Encéfalo/metabolismo , Neurônios/metabolismo , Transcriptoma , Conjuntos de Dados como AssuntoRESUMO
Telomerase activation is a crucial step in melanomagenesis, often occurring because of ultraviolet radiation (UVR)-induced mutations at the telomerase gene (TERT) promoter and rendering TERT transcription in response to the activated Raf-MAP kinase pathway by BRAFV600E mutation. Due to the excessively long telomeres in mice, this process does not occur during melanomagenesis in mouse models. To investigate the impact of telomere dysfunction on melanomagenesis, BrafV600E was induced in generations 1 and 4 (G1 and G4) of Tert-/- mice. Our findings revealed that, regardless of UVR exposure, melanoma development was delayed in G4 mice, which had shorter telomeres compared to G1 and wild-type C57BL/6J (G0) mice. Moreover, many G4 tumors displayed an accumulation of excessive DNA damage, as evidenced by increased γH2A.X staining. Tumors from UVR-exposed mice exhibited elevated p53 protein expression. Cultured tumor cells isolated from G4 mice displayed abundant chromosomal fusions and rearrangements, indicative of telomere dysfunction in these cells. Additionally, tumor cells derived from UVB-exposed mice exhibited constitutively elevated expression of mutant p53 proteins, suggesting that p53 was a target of UVB-induced mutagenesis. Taken together, our findings suggest that telomere dysfunction hampers melanomagenesis, and targeting telomere crisis-mediated genomic instability may hold promise for the prevention and treatment of melanoma.
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Melanoma , Proteínas Proto-Oncogênicas B-raf , Telomerase , Animais , Camundongos , Melanoma/genética , Melanoma/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mutação , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/metabolismo , Telomerase/genética , Telomerase/metabolismo , Telômero/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Raios Ultravioleta/efeitos adversosRESUMO
The bacterial canker of kiwifruit caused by Pseudomonas syringae pv. actinidiae (Psa) is the most devastating disease threatening the global kiwifruit production. This pathogen delivers multiple effector proteins into plant cells to resist plant immune responses and facilitate their survival. Here, we focused on the unique effector HopZ5 in Psa, which previously has been reported to have virulence functions. In this study, our results showed that HopZ5 could cause macroscopic cell death and trigger a serious immune response by agroinfiltration in Nicotiana benthamiana, along with upregulated expression of immunity-related genes and significant accumulation of reactive oxygen species and callose. Subsequently, we confirmed that HopZ5 interacted with the phosphoserine-binding protein GF14C in both the nonhost plant N. benthamiana (NbGF14C) and the host plant kiwifruit (AcGF14C), and silencing of NbGF14C compromised HopZ5-mediated cell death, suggesting that GF14C plays a crucial role in the detection of HopZ5. Further studies showed that overexpression of NbGF14C both markedly reduced the infection of Sclerotinia sclerotiorum and Phytophthora capsica in N. benthamiana, and overexpression of AcGF14C significantly enhanced the resistance of kiwifruit against Psa, indicating that GF14C positively regulates plant immunity. Collectively, our results revealed that the virulence effector HopZ5 could be recognized by plants and interact with GF14C to activate plant immunity.
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Actinidia , Proteínas de Bactérias , Nicotiana , Doenças das Plantas , Imunidade Vegetal , Pseudomonas syringae , Pseudomonas syringae/patogenicidade , Pseudomonas syringae/fisiologia , Doenças das Plantas/microbiologia , Doenças das Plantas/imunologia , Nicotiana/microbiologia , Nicotiana/imunologia , Actinidia/microbiologia , Actinidia/imunologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Virulência , Phytophthora/patogenicidade , Phytophthora/fisiologia , Glucanos/metabolismo , Morte Celular , Ascomicetos/fisiologia , Ascomicetos/patogenicidade , Espécies Reativas de Oxigênio/metabolismo , Regulação da Expressão Gênica de PlantasRESUMO
PURPOSE: This study investigated the value of whole tumor apparent diffusion coefficient (ADC) histogram parameters and magnetic resonance imaging (MRI) semantic features in predicting meningioma progesterone receptor (PR) expression. MATERIALS AND METHODS: The imaging, pathological, and clinical data of 53 patients with PR-negative meningiomas and 52 patients with PR-positive meningiomas were retrospectively reviewed. The whole tumor was outlined using Firevoxel software, and the ADC histogram parameters were calculated. The differences in ADC histogram parameters and MRI semantic features were compared between the two groups. The predictive values of parameters for PR expression were assessed using receiver operating characteristic curves. The correlation between whole-tumor ADC histogram parameters and PR expression in meningiomas was also analyzed. RESULTS: Grading was able to predict the PR expression in meningiomas (p = 0.012), though the semantic features of MRI were not (all p > 0.05). The mean, Perc.01, Perc.05, Perc.10, Perc.25, and Perc.50 histogram parameters were able to predict meningioma PR expression (all p < 0.05). The predictive performance of the combined histogram parameters improved, and the combination of grade and histogram parameters provided the optimal predictive value, with an area under the curve of 0.849 (95%CI: 0.766-0.911) and sensitivity, specificity, ACC, PPV, and NPV of 73.08%, 81.13%, 77.14%, 79.20%, and 75.40%, respectively. The mean, Perc.01, Perc.05, Perc.10, Perc.25, and Perc.50 histogram parameters were positively correlated with PR expression (all p < 0.05). CONCLUSION: Whole tumor ADC histogram parameters have additional clinical value in predicting PR expression in meningiomas.
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Imagem de Difusão por Ressonância Magnética , Neoplasias Meníngeas , Meningioma , Receptores de Progesterona , Humanos , Meningioma/diagnóstico por imagem , Meningioma/patologia , Meningioma/metabolismo , Feminino , Pessoa de Meia-Idade , Masculino , Neoplasias Meníngeas/diagnóstico por imagem , Neoplasias Meníngeas/patologia , Neoplasias Meníngeas/metabolismo , Receptores de Progesterona/metabolismo , Adulto , Imagem de Difusão por Ressonância Magnética/métodos , Idoso , Estudos Retrospectivos , Valor Preditivo dos TestesRESUMO
Multiple independent sequence variants of the hTERT locus have been associated with telomere length and cancer risks in genome-wide association studies. Here, we identified an intronic variable number tandem repeat, VNTR2-1, as an enhancer-like element, which activated hTERT transcription in a cell in a chromatin-dependent manner. VNTR2-1, consisting of 42-bp repeats with an array of enhancer boxes, cooperated with the proximal promoter in the regulation of hTERT transcription by basic helix-loop-helix transcription factors and maintained hTERT expression during embryonic stem-cell differentiation. Genomic deletion of VNTR2-1 in MelJuSo melanoma cells markedly reduced hTERT transcription, leading to telomere shortening, cellular senescence, and impairment of xenograft tumor growth. Interestingly, VNTR2-1 lengths varied widely in human populations; hTERT alleles with shorter VNTR2-1 were underrepresented in African American centenarians, indicating its role in human aging. Therefore, this polymorphic element is likely a missing link in the telomerase regulatory network and a molecular basis for genetic diversities of telomere homeostasis and age-related disease susceptibilities.
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Repetições Minissatélites/genética , Polimorfismo Genético , Telomerase/genética , Ativação Transcricional , Negro ou Afro-Americano/genética , Idoso de 80 Anos ou mais , Animais , Sequência de Bases , Diferenciação Celular/genética , Linhagem Celular , Proliferação de Células/genética , Cromossomos Artificiais Bacterianos/genética , Elementos E-Box/genética , Genoma Humano , Células-Tronco Embrionárias Humanas/metabolismo , Humanos , Camundongos Nus , Neoplasias/genética , Neoplasias/patologia , Regiões Promotoras Genéticas , Ligação Proteica/genética , Deleção de Sequência/genética , Homeostase do Telômero/genéticaRESUMO
Addressing common challenges such as limited indicators, poor adaptability, and imprecise modeling in gas pre-warning systems for driving faces, this study proposes a hybrid predictive and pre-warning model grounded in time-series analysis. The aim is to tackle the effects of broad application across diverse mines and insufficient data on warning accuracy. Firstly, we introduce an adaptive normalization (AN) model for standardizing gas sequence data, prioritizing recent information to better capture the time-series characteristics of gas readings. Coupled with the Gated Recurrent Unit (GRU) model, AN demonstrates superior forecasting performance compared to other standardization techniques. Next, Ensemble Empirical Mode Decomposition (EEMD) is used for feature extraction, guiding the selection of the Variational Mode Decomposition (VMD) order. Minimal decomposition errors validate the efficacy of this approach. Furthermore, enhancements to the transformer framework are made to manage non-linearities, overcome gradient vanishing, and effectively analyze long time-series sequences. To boost versatility across different mining scenarios, the Optuna framework facilitates multiparameter optimization, with xgbRegressor employed for accurate error assessment. Predictive outputs are benchmarked against Recurrent Neural Networks (RNN), GRU, Long Short-Term Memory (LSTM), and Bidirectional LSTM (BiLSTM), where the hybrid model achieves an R-squared value of 0.980975 and a Mean Absolute Error (MAE) of 0.000149, highlighting its top performance. To cope with data scarcity, bootstrapping is applied to estimate the confidence intervals of the hybrid model. Dimensional analysis aids in creating real-time, relative gas emission metrics, while persistent anomaly detection monitors sudden time-series spikes, enabling unsupervised early alerts for gas bursts. This model demonstrates strong predictive prowess and effective pre-warning capabilities, offering technological reinforcement for advancing intelligent coal mine operations.
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Spinal cord injury (SCI) often causes severe neurological dysfunction, and facilitating neurite elongation is particularly important in its treatment. Astrocytes (AS) play an important role in the central nervous system (CNS), and their high plasticity and versatility provide a feasible entry point for relevant research. Our purpose was to explore whether extracellular vesicles (EVs) from astrocytes (AS-EVs) and lipopolysaccharide (LPS)-preactivated astrocytes (LPAS-EVs) facilitate neurite elongation, to explore the underlying mechanism, and to verify whether these EVs promote locomotor recovery in rats. We used LPS to preactivate astrocytes and cocultured them with PC12 cells to observe neurite changes, then extracted and identified AS-EVs and LPAS-EVs and the role and mechanism of these EVs in facilitating neurite elongation was examined in vivo and vitro. We demonstrated that AS-EVs and LPAS-EVs facilitated the elongation of neurites and the recovery of rats with SCI. LPAS-EVs had a stronger effect than AS-EVs, by activating the Hippo pathway, promoting monopole spindle binding protein 1 (MOB1) expression, and reducing Yes-associated protein (YAP) levels. The data also suggest a feedback regulation between MOB1 and p-YAP/YAP. In sum, AS-EVs and LPAS-EVs can play an active role in facilitating neurite elongation by activating the Hippo pathway. These findings provide a new strategy for treating SCI and other CNS-related injuries.
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Astrócitos/citologia , Vesículas Extracelulares/transplante , Via de Sinalização Hippo , Neuritos/fisiologia , Neurônios/citologia , Traumatismos da Medula Espinal/terapia , Animais , Astrócitos/metabolismo , Vesículas Extracelulares/metabolismo , Células PC12 , Ratos , Ratos Sprague-Dawley , Traumatismos da Medula Espinal/metabolismo , Traumatismos da Medula Espinal/patologiaRESUMO
Extrachromosomal mobile genetic elements (eMGEs), including phages and plasmids, that can move across different microbes, play important roles in genome evolution and shaping the structure of microbial communities. However, we still know very little about eMGEs, especially their abundances, distributions and putative functions in microbiomes. Thus, a comprehensive description of eMGEs is of great utility. Here we present mMGE, a comprehensive catalog of 517 251 non-redundant eMGEs, including 92 492 plasmids and 424 759 phages, derived from diverse body sites of 66 425 human metagenomic samples. About half the eMGEs could be further grouped into 70 074 clusters using relaxed criteria (referred as to eMGE clusters below). We provide extensive annotations of the identified eMGEs including sequence characteristics, taxonomy affiliation, gene contents and their prokaryotic hosts. We also calculate the prevalence, both within and across samples for each eMGE and eMGE cluster, enabling users to see putative associations of eMGEs with human phenotypes or their distribution preferences. All eMGE records can be browsed or queried in multiple ways, such as eMGE clusters, metagenomic samples and associated hosts. The mMGE is equipped with a user-friendly interface and a BLAST server, facilitating easy access/queries to all its contents easily. mMGE is freely available for academic use at: https://mgedb.comp-sysbio.org.
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Cromossomos Humanos/genética , Bases de Dados Genéticas , Sequências Repetitivas Dispersas/genética , Metagenômica , Análise por Conglomerados , Sequência Conservada , Mapeamento de Sequências Contíguas , Evolução Molecular , Corpo Humano , Humanos , Anotação de Sequência Molecular , Interface Usuário-ComputadorRESUMO
The incidence of heart failure mainly resulting from cardiac hypertrophy and fibrosis increases sharply in post-menopausal women compared with men at the same age, which indicates a cardioprotective role of estrogen. Previous studies in our group have shown that the novel estrogen receptor G Protein Coupled Receptor 30 (GPR30) could attenuate myocardial fibrosis caused by ischemic heart disease. However, the role of GPR30 in myocardial hypertrophy in ovariectomized mice has not been investigated yet. In this study, female mice with bilateral ovariectomy or sham surgery underwent transverse aortic constriction (TAC) surgery. After 8 weeks, mice in the OVX + TAC group exhibited more severe myocardial hypertrophy and fibrosis than mice in the TAC group. G1, the specific agonist of GPR30, could attenuate myocardial hypertrophy and fibrosis of mice in the OVX + TAC group. Furthermore, the expression of LC3II was significantly higher in the OVX + TAC group than in the OVX + TAC + G1 group, which indicates that autophagy might play an important role in this process. An in vitro study showed that G1 alleviated AngiotensionII (AngII)-induced hypertrophy and reduced the autophagy level of H9c2 cells, as revealed by LC3II expression and tandem mRFP-GFP-LC3 fluorescence analysis. Additionally, Western blot results showed that the AKT/mTOR pathway was inhibited in the AngII group, whereas it was restored in the AngII + G1 group. To further verify the mechanism, PI3K inhibitor LY294002 or autophagy activator rapamycin was added in the AngII + G1 group, and the antihypertrophy effect of G1 on H9c2 cells was blocked by LY294002 or rapamycin. In summary, our results demonstrate that G1 can attenuate cardiac hypertrophy and fibrosis and improve the cardiac function of mice in the OVX + TAC group through AKT/mTOR mediated inhibition of autophagy. Thus, this study demonstrates a potential option for the drug treatment of pressure overload-induced cardiac hypertrophy in postmenopausal women.
Assuntos
Estenose da Valva Aórtica , Proteínas Proto-Oncogênicas c-akt , Camundongos , Feminino , Animais , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores de Estrogênio/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Cardiomegalia/tratamento farmacológico , Cardiomegalia/etiologia , Cardiomegalia/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Estenose da Valva Aórtica/patologia , Autofagia , Fibrose , Sirolimo/farmacologia , Sirolimo/uso terapêutico , Camundongos Endogâmicos C57BL , Miócitos Cardíacos/metabolismo , Miocárdio/metabolismoRESUMO
PURPOSE: NLRP3 inflammasome mediates myocardial ischemia/reperfusion (MI/R) injury and diabetic vascular endothelia dysfunction. However, the role of NLRP3 inflammasome in MI/R injury with diabetes has not been fully described. Irisin plays an important role in anti-inflammation and improves endothelial function in type 2 diabetes. The current study aimed to investigate the effect of irisin on regulating NLRP3 inflammasome activation in diabetic vascular endothelia dysfunction. METHODS: Cardiac microvascular endothelial cells (CMECs) were cultured and subjected to high glucose/high fat (HG/HF) receiving hypoxia/reoxygenation (H/R) with irisin incubation or not. Then, apoptosis, viability, migration, NO secretion, and inflammasome activation were examined. RESULTS: The hypoxic CMECs exhibited increased apoptosis, impaired viability, and migration, even decreased NO secretion and enhanced inflammasome activation. Moreover, irisin incubation decreased NLRP3 activation and attenuated cell injury in HG/HF cultured CMECs subjected to H/R injury, which was abolished by NLRP3 inflammasome activation. Meanwhile, NLRP3 inflammasome siRNA also attenuated H/R injury in CMECs under HG/HF condition. CONCLUSION: The current study demonstrated for the first time that irisin inhibits NLRP3 inflammasome activation in CMECs as a novel mechanism in myocardial ischemia/reperfusion injury in diabetes.
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Diabetes Mellitus Tipo 2 , Traumatismo por Reperfusão Miocárdica , Traumatismo por Reperfusão , Humanos , Inflamassomos/farmacologia , Células Endoteliais , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Fibronectinas/farmacologiaRESUMO
MOTIVATION: Aligning single-cell transcriptomes is important for the joint analysis of multiple single-cell RNA sequencing datasets, which in turn is vital to establishing a holistic cellular landscape of certain biological processes. Although numbers of approaches have been proposed for this problem, most of which only consider mutual neighbors when aligning the cells without taking into account known cell type annotations. RESULTS: In this work, we present MAT2 that aligns cells in the manifold space with a deep neural network employing contrastive learning strategy. Compared with other manifold-based approaches, MAT2 has two-fold advantages. Firstly, with cell triplets defined based on known cell type annotations, the consensus manifold yielded by the alignment procedure is more robust especially for datasets with limited common cell types. Secondly, the batch-effect-free gene expression reconstructed by MAT2 can better help annotate cell types. Benchmarking results on real scRNA-seq datasets demonstrate that MAT2 outperforms existing popular methods. Moreover, with MAT2, the hematopoietic stem cells are found to differentiate at different paces between human and mouse. AVAILABILITY AND IMPLEMENTATION: MAT2 is publicly available at https://github.com/Zhang-Jinglong/MAT2. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.
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A considerable number of glioblastoma (GBM) patients developed drug resistance to Temozolomide (TMZ) during chemotherapy, resulting in therapeutic failure and tumor recurrence. However, the exact mechanism of TMZ chemoresistance in GBM is still poorly clarified. As a novel identified lncRNA, LINC00520 was located on chromosome 14 and overexpressed in multiple human cancers. This study was designed and conducted to investigate the role and underlying mechanism of LINC00520 in GBM chemoresistance to TMZ. The qRT-PCR assay demonstrated that LINC00520 was significantly overexpressed in TMZ-sensitive and/or TMZ-resistant GBM cells (P < 0.001). The silencing of LINC00520 markedly reduced the cell viability, suppressed colony formation, induced cell apoptosis and G1/S phase arrest in TMZ-resistant cells (P < 0.001). In contrast, overexpression of LINC00520 conferred TMZ-resistant phenotype of GBM cells in vitro (P < 0.001). The orthotopic xenograft model was established and the results indicated that the volume of tumor xenografts in vivo was markedly inhibited by TMZ treatment after the silencing of LINC00520 (P < 0.001). Luciferase reporter assay and chromatin immunoprecipitation (ChIP) assay revealed a strong affinity of transcription factor STAT3 to the promoter regions of LINC00520, suggesting that STAT3 mediated the aberrant expression of LINC00520 in GBM. Further experiments demonstrated that LINC00520 could interact with RNA-binding protein LIN28B to inhibit autophagy and reduce DNA damage, thereby contributing to TMZ chemoresistance in GBM. These findings suggested that STAT3/LINC00520/LIN28B axis might be a promising target to improve TMZ chemoresistance of GBM.
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BACKGROUND: Burr-hole craniostomy (BHC) is considered to be the most effective method for the treatment of chronic subdural hematoma (CSDH), and middle meningeal artery embolization is a new therapy used in clinical practice in recent years to treat CSDH. However, the optimal therapeutic effect of these 2 procedures is still controversial. This study prospectively designed a modified burr-hole craniostomy (mBHC) with drainage to treat CSDH. METHODS: A total of 101 patients diagnosed with CSDH from January 2019 to April 2020 were prospectively included in this study. They were divided into BHC and mBHC groups. Among them, 40 selected CSDH patients received mBHC treatment. For comparison, 61 CSDH patients who received BHC treatment were used as the control group. Primary outcomes were hematoma recurrence and postoperative complications. Secondary outcomes included midline recovery, hematoma clearance, operation time, and hospital stay. The Chi-square test was used to compare the 6-month follow-up results between the 2 groups. RESULTS: Among patients treated with mBHC, 39 patients had a good prognosis, and one 87-year-old patient with bilateral hematoma died of postoperative heart failure. Of the patients treated with BHC, 52 patients had good prognoses, and one 53-year-old patient with unilateral hematoma died of postoperative acute intracranial bleeding. During the 6-month follow-up period, no relapse occurred in the patients treated with mBHC, whereas 8 (13%) of the patients treated with BHC relapsed. There was a significant difference in the recurrence rate between the 2 groups (Pâ<â0.05). In addition, midline recovery, hematoma clearance rate, operation time, and complications were found to be significantly different statistically (Pâ<â0.05), and other characteristics of operation and outcome were not significantly different (Pâ>â0.05) between the 2 groups. CONCLUSIONS: Modified burr-hole craniostomy has a positive therapeutic effect on patients with CSDH and is more effective than conventional BHC therapy.
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Hematoma Subdural Crônico , Adulto , Drenagem/métodos , Hematoma/cirurgia , Hematoma Subdural Crônico/cirurgia , Humanos , Recidiva , Estudos Retrospectivos , Resultado do Tratamento , TrepanaçãoRESUMO
Sorghum (Sorghum bicolor) is known to have a more robust capability of phosphorus uptake than many other cereal plants, which could be attributed to its phosphate transporter 1 (Pht1) that has a high phosphorus affinity. There are eleven SbPht1 genes in the sorghum genome, nine of which are expressed in sorghum roots or shoots in response to phosphorus deficiency (low-P). The molecular features of these nine genes were investigated by gene expression analysis, subcellular localization, and a yeast mutant complementation growth assay. They were found to be induced in response to low-P stress in root or shoot. All these SbPht1 proteins were found to be localized on the cell membrane, and SbPht1;8 was also detected in the endoplasmic reticulum. These SbPht1s were able to complement the yeast mutant EY917 that lacks all the functional phosphate transporters, and, among them, SbPht1;5, SbPht1;6 and SbPht1;8 could partially complement the yeast mutant strain EY917 in low-P conditions. Overall, these findings demonstrate that SbPht1;5, SbPht1;6, and SbPht1;8 are high-affinity phosphate transporters. SbPht1;5, in particular, is specifically involved in phosphorus uptake in the roots, whilst SbPht1;6 and SbPht1;8 are key players in both P uptake and P transport in response to low-P stress in sorghum.
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Proteínas de Transporte de Fosfato , Sorghum , Proteínas de Transporte de Fosfato/genética , Proteínas de Transporte de Fosfato/metabolismo , Sorghum/genética , Sorghum/metabolismo , Grão Comestível/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Regulação da Expressão Gênica de Plantas , Fosfatos/metabolismo , Fósforo/metabolismoRESUMO
BACKGROUND: Phosphorus (P) deficiency in soil is a worldwide issue and a major constraint on the production of sorghum, which is an important staple food, forage and energy crop. The depletion of P reserves and the increasing price of P fertilizer make fertilizer application impractical, especially in developing countries. Therefore, identifying sorghum accessions with low-P tolerance and understanding the underlying molecular basis for this tolerance will facilitate the breeding of P-efficient plants, thereby resolving the P crisis in sorghum farming. However, knowledge in these areas is very limited. RESULTS: The 29 sorghum accessions used in this study demonstrated great variability in their tolerance to low-P stress. The internal P content in the shoot was correlated with P tolerance. A low-P-tolerant accession and a low-P-sensitive accession were chosen for RNA-seq analysis to identify potential underlying molecular mechanisms. A total of 2089 candidate genes related to P starvation tolerance were revealed and found to be enriched in 11 pathways. Gene Ontology (GO) enrichment analyses showed that the candidate genes were associated with oxidoreductase activity. In addition, further study showed that malate affected the length of the primary root and the number of tips in sorghum suffering from low-P stress. CONCLUSIONS: Our results show that acquisition of P from soil contributes to low-P tolerance in different sorghum accessions; however, the underlying molecular mechanism is complicated. Plant hormone (including auxin, ethylene, jasmonic acid, salicylic acid and abscisic acid) signal transduction related genes and many transcriptional factors were found to be involved in low-P tolerance in sorghum. The identified accessions will be useful for breeding new sorghum varieties with enhanced P starvation tolerance.
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Fósforo/deficiência , Reguladores de Crescimento de Plantas/metabolismo , Transdução de Sinais/genética , Sorghum/genética , Grão Comestível/genética , Grão Comestível/fisiologia , Perfilação da Expressão Gênica , Solo/química , Sorghum/fisiologiaRESUMO
BACKGROUND AND AIM: It has been well documented that Notch signaling is involved in liver regeneration. However, the exact molecular mechanism mediating this process is not fully elucidated. The current study aimed to investigate the role of Notch signaling regulating cell cycle in proliferating hepatocytes in liver regeneration after partial hepatectomy (PHx, 67% resection) and the related molecular mechanism. METHODS: Partial hepatectomy was performed in Sprague Dawley rats, and remnant livers were harvested 0, 1, 3, 5, and 7 days after operation, and primary hepatocytes were isolated to investigate the molecular mechanism. RESULTS: Notch signaling activation and hepatocyte proliferation were significantly increased after PHx, while treatment with FLI-06, the inhibitor of γ-secreting enzyme, blocked these trends. Besides, inhibition of Notch signaling led to dysregulation of cell cycle and cell-cycle components. Furthermore, Akti-1/2 (a selective Akt inhibitor) and PX-478 (a selective Hif-1α inhibitor) inhibited hepatocyte proliferation and liver regeneration after PHx, and the effect of downstream molecules activation by Jagged-1 (Notch-1 ligand) in hepatocytes was abolished by FLI-06, Akti-1/2, and PX-478. CONCLUSION: The current study demonstrated for the first time that Notch signaling regulated cell cycle in proliferating hepatocytes involved in liver regeneration through NICD/Akt Akt/Hif-1α pathway.
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Ciclo Celular/genética , Ciclo Celular/fisiologia , Proliferação de Células/genética , Proliferação de Células/fisiologia , Hepatócitos/citologia , Hepatócitos/fisiologia , Regeneração Hepática/genética , Regeneração Hepática/fisiologia , Receptores Notch/fisiologia , Transdução de Sinais/fisiologia , Animais , Células HEK293 , Hepatectomia , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/fisiologia , Masculino , Proteínas Proto-Oncogênicas c-akt/fisiologia , Ratos Sprague-DawleyRESUMO
H3K4me3 is an important epigenetic modification that plays a critical role in maintaining self-renewal of mouse embryonic stem cells (mESCs). H3K4me3 is catalyzed mainly by the mixed lineage leukemia (MLL) methyl-transferase complex. ASH2L, a core subunit of the MLL complex, participates in regulating the open state of chromatin in mESCs. There are two isoforms of the ASH2L protein: ASH2L-1 (80 kDa), which only exists in mouse embryonic fibroblasts and ASH2L-2 (65 kDa), which is the predominant isoform in mESCs. The roles of Ash2l-1 and Ash2l-2 in mESCs have not yet been elucidated. In this study, we established Ash2l-1 -/- and Ash2l-2 -/- knockout mESCs using CRISPR/Cas9. Alkaline phosphatase (AP) staining, immunofluorescence staining, and qRT-PCR showed that there were no obvious differences on the expression level of AP and pluripotent transcription factors (Nanog, Oct4, sox2 and Klf4) among Ash2l-1 -/- mESCs, Ash2l-2 -/- mESCs and wild type (WT) mESCs. However, analysis of embryoid body (EB) differentiation showed that the expression level of Snai2 (ectoderm gene) and Gata4 (endoderm gene) in Ash2l-1 -/- EBs was significantly lower than that in WT EBs (P<0.01). Western blotting assay revealed that the expression of ASH2L-2 was significantly increased (P<0.01) in Ash2l-1 -/- mESCs and vice versa. However, there were no obvious differences on the genomic H3K4me3 level among Ash2l-1 -/- mESCs, Ash2l-2 -/- mESCs and WT mESCs. These results indicate that there exist compensation effects between Ash2l-1 and Ash2l-2. Bioinformatic analysis predicted that there were three and 16 potential binding sites for pluripotency transcription factors located in the promoter of Ash2l-1 and Ash2l-2, respectively. Theses transcription factors may mediate the compensation effect between Ash2l-1 and Ash2l-2. Collectively, these results indicate that the compensation effects between Ash2l-1 and Ash2l-2 may be involved in the maintenance of mESCs pluripotency and the regulation of genomic H3K4me3.
Assuntos
Proteínas de Ligação a DNA/metabolismo , Camundongos/embriologia , Camundongos/metabolismo , Células-Tronco Embrionárias Murinas/citologia , Proteínas Nucleares/metabolismo , Fatores de Transcrição/metabolismo , Animais , Proteínas de Ligação a DNA/genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Histonas/genética , Histonas/metabolismo , Fator 4 Semelhante a Kruppel , Masculino , Camundongos/genética , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células-Tronco Embrionárias Murinas/metabolismo , Proteínas Nucleares/genética , Fatores de Transcrição/genéticaRESUMO
It has been well documented that hypoadiponectinemia is associated with impaired endothelium-dependent vasodilation. However, the exact molecular mechanism which mediates this process has not been fully described. The current study aimed to investigate the role of hypoadiponectinemia-induced NLRP3 inflammasome activation in diabetic vascular endothelial dysfunction and its molecular mechanism. Male adult adiponectin knockout mice and wild type mice were fed with a high fat diet to establish a type 2 diabetic mellitus model. In addition, human umbilical vein endothelial cells (HUVECs) were cultured and subjected to high glucose/high fat (HG/HF). The NLRP3 inflammasome activation was increased in type 2 diabetic mice and treatment of diabetic aortic segments with MCC950, a potent selective inhibitor of NLRP3 inflammasome ex vivo improved endothelial-dependent vasorelaxation. NLRP3 inflammasome activation and vascular endothelial injury were significantly increased in APN-KO mice compared with WT mice in diabetes and MCC950 decreased diabetic vascular endothelial dysfunction to comparable levels in APN-KO mice and WT mice. Adiponectin could decrease NLRP3 inflammasome activation and attenuate endothelial cell injury, which was abolished by NLRP3 inflammasome overexpression. Inhibition of peroxynitrite formation preferentially attenuated NLRP3 inflammasome activation in APN-KO diabetic mice. The current study demonstrated for the first time that hypoadiponectinemia-induced NLRP3 inflammasome activation was a novel mechanism of diabetic vascular endothelial dysfunction.
Assuntos
Adiponectina/deficiência , Angiopatias Diabéticas/metabolismo , Endotélio Vascular/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Inflamassomos/metabolismo , Erros Inatos do Metabolismo/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Adiponectina/genética , Adiponectina/metabolismo , Animais , Aorta/metabolismo , Aorta/patologia , Angiopatias Diabéticas/genética , Angiopatias Diabéticas/patologia , Endotélio Vascular/patologia , Células Endoteliais da Veia Umbilical Humana/patologia , Humanos , Inflamassomos/genética , Masculino , Erros Inatos do Metabolismo/genética , Erros Inatos do Metabolismo/patologia , Camundongos , Camundongos Knockout , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Vasodilatação/genéticaRESUMO
Nitric oxide is a potent anti-apoptotic and cardioprotective molecule in healthy animals. However, recent study demonstrates that overexpression of eNOS exacerbates the liver injury in diabetic animals. whether diabetes may also alter NO's biologic activity in ischaemic/reperfused heart remains unknown. The present experiment was designed to determine whether the nitric oxide donor, S-nitrosoglutathione, may exert different effects on diabetic and non-diabetic myocardial ischaemia/reperfusion (MI/R) injury. Diabetic state was induced in mice by multiple intraperitoneal injections of low-dose streptozotocin (STZ). The control or diabetic mice were subjected to 30 minutes ischaemia and 3 or 24 hours reperfusion. At 10 minutes before reperfusion, diabetic and non-diabetic mice were received an intraperitoneal injection of S-nitrosoglutathione (GSNO, a nitric oxide donor, 1 µmol/kg). GSNO attenuated MI/R injury in non-diabetic mice, as measured by improved cardiac function, reduced infarct size and decreased cardiomyocyte apoptosis. In contrast, GSNO failed to attenuate but, rather, aggravated the MI/R injury in diabetic mice. Mechanically, the diabetic heart exhibited an increased nitrative/oxidative stress level, as measured by peroxynitrite formation, compared with non-diabetic mice. Co-administration of GSNO with EUK134 (a peroxynitrite scavenger) or MnTE-2-PyP5 (a superoxide dismutase mimetic) or Apocynin (a NADPH oxidase inhibitor) 10 minutes before reperfusion significantly decreased the MI/R-induced peroxynitrite formation and the MI/R injury. Collectively, the present study for the first time demonstrated that diabetes may cause superoxide overproduction, increase NO inactivation and peroxynitrite formation, and thus convert GSNO from a cardioprotective molecule to a cardiotoxic molecule.
Assuntos
Diabetes Mellitus Experimental/complicações , Traumatismo por Reperfusão Miocárdica/complicações , Doadores de Óxido Nítrico/farmacologia , S-Nitrosoglutationa/farmacologia , Animais , Interações Medicamentosas , Camundongos , Camundongos Endogâmicos C57BL , Traumatismo por Reperfusão Miocárdica/metabolismo , Óxido Nítrico/metabolismo , Compostos Organometálicos/farmacologia , Salicilatos/farmacologiaRESUMO
Diabetic mellitus (DM) portends poor prognosis concerning pressure overloaded heart disease. Branched-chain amino acids (BCAAs), elements of essential amino acids, have been found altered in its catabolism in diabetes decades ago. However, the relationship between BCAAs and DM induced deterioration of pressure overloaded heart disease remains controversial. This study is aimed to investigate the particular effect of BCKA, a metabolite of BCAA, on myocardial injury induced by pressure overloaded. Primary cardiomyocytes were incubated with or without BCKA and followed by treatment with isoproterenol (ISO); then cell viability was detected by CCK8 and apoptosis was examined by TUNNEL stain and caspase-3 activity analysis. Compared to non-BCKA incubated group, BCKA incubation decreased cell survival and increased apoptosis concentration dependently. Furthermore, Western blot assay showed that mTORC2-Akt pathway was significantly inactivated by BCKA incubation. Moreover, overexpression of rictor, a vital component of mTORC2, significantly abolished the adverse effects of BCKA on apoptosis susceptibility of cardiomyocytes. These results indicate that BCKA contribute to vulnerability of cardiomyocytes in stimulated stress via inactivation of mTORC2-Akt pathway.