RESUMEN
Circular RNAs (circRNAs), which are increasingly being implicated in a variety of functions in normal and cancerous cells1-5, are formed by back-splicing of precursor mRNAs in the nucleus6-10. circRNAs are predominantly localized in the cytoplasm, indicating that they must be exported from the nucleus. Here we identify a pathway that is specific for the nuclear export of circular RNA. This pathway requires Ran-GTP, exportin-2 and IGF2BP1. Enhancing the nuclear Ran-GTP gradient by depletion or chemical inhibition of the major protein exporter CRM1 selectively increases the nuclear export of circRNAs, while reducing the nuclear Ran-GTP gradient selectively blocks circRNA export. Depletion or knockout of exportin-2 specifically inhibits nuclear export of circRNA. Analysis of nuclear circRNA-binding proteins reveals that interaction between IGF2BP1 and circRNA is enhanced by Ran-GTP. The formation of circRNA export complexes in the nucleus is promoted by Ran-GTP through its interactions with exportin-2, circRNA and IGF2BP1. Our findings demonstrate that adaptors such as IGF2BP1 that bind directly to circular RNAs recruit Ran-GTP and exportin-2 to export circRNAs in a mechanism that is analogous to protein export, rather than mRNA export.
Asunto(s)
Transporte Activo de Núcleo Celular , Núcleo Celular , Transporte de ARN , ARN Circular , Transporte Activo de Núcleo Celular/fisiología , Núcleo Celular/metabolismo , Guanosina Trifosfato/metabolismo , Carioferinas/antagonistas & inhibidores , Carioferinas/deficiencia , Carioferinas/genética , Carioferinas/metabolismo , Proteínas Nucleares/metabolismo , Proteína de Unión al GTP ran/metabolismo , ARN Circular/metabolismo , Precursores del ARN/genética , Precursores del ARN/metabolismo , Proteínas de Unión al ARN/metabolismo , Proteína Exportina 1/metabolismo , Transporte de ProteínasRESUMEN
Histone methyltransferases of the nuclear receptor-binding SET domain protein (NSD) family, including NSD1, NSD2 and NSD3, have crucial roles in chromatin regulation and are implicated in oncogenesis1,2. NSD enzymes exhibit an autoinhibitory state that is relieved by binding to nucleosomes, enabling dimethylation of histone H3 at Lys36 (H3K36)3-7. However, the molecular basis that underlies this mechanism is largely unknown. Here we solve the cryo-electron microscopy structures of NSD2 and NSD3 bound to mononucleosomes. We find that binding of NSD2 and NSD3 to mononucleosomes causes DNA near the linker region to unwrap, which facilitates insertion of the catalytic core between the histone octamer and the unwrapped segment of DNA. A network of DNA- and histone-specific contacts between NSD2 or NSD3 and the nucleosome precisely defines the position of the enzyme on the nucleosome, explaining the specificity of methylation to H3K36. Intermolecular contacts between NSD proteins and nucleosomes are altered by several recurrent cancer-associated mutations in NSD2 and NSD3. NSDs that contain these mutations are catalytically hyperactive in vitro and in cells, and their ectopic expression promotes the proliferation of cancer cells and the growth of xenograft tumours. Together, our research provides molecular insights into the nucleosome-based recognition and histone-modification mechanisms of NSD2 and NSD3, which could lead to strategies for therapeutic targeting of proteins of the NSD family.
Asunto(s)
N-Metiltransferasa de Histona-Lisina/metabolismo , Histonas/química , Histonas/metabolismo , Proteínas Nucleares/metabolismo , Nucleosomas/química , Nucleosomas/metabolismo , Proteínas Represoras/metabolismo , Sitios de Unión , Biocatálisis , Línea Celular Tumoral , Proliferación Celular , Microscopía por Crioelectrón , Xenoinjertos , N-Metiltransferasa de Histona-Lisina/genética , N-Metiltransferasa de Histona-Lisina/ultraestructura , Histonas/ultraestructura , Humanos , Metilación , Modelos Moleculares , Complejos Multiproteicos/química , Complejos Multiproteicos/genética , Complejos Multiproteicos/metabolismo , Complejos Multiproteicos/ultraestructura , Mutación , Trasplante de Neoplasias , Neoplasias/genética , Neoplasias/patología , Proteínas Nucleares/genética , Proteínas Nucleares/ultraestructura , Nucleosomas/ultraestructura , Fenotipo , Unión Proteica , Proteínas Represoras/genética , Proteínas Represoras/ultraestructuraRESUMEN
Ribosome biogenesis is a complex process, and dozens of factors are required to facilitate and regulate the subunit assembly in bacteria. The 2'-O-methylation of U2552 in 23S rRNA by methyltransferase RrmJ is a crucial step in late-stage assembly of the 50S subunit. Its absence results in severe growth defect and marked accumulation of pre50S assembly intermediates. In the present work, we employed cryoelectron microscopy to characterize a set of late-stage pre50S particles isolated from an Escherichia coli ΔrrmJ strain. These assembly intermediates (solved at 3.2 to 3.8 Å resolution) define a collection of late-stage particles on a progressive assembly pathway. Apart from the absence of L16, L35, and L36, major structural differences between these intermediates and the mature 50S subunit are clustered near the peptidyl transferase center, such as H38, H68-71, and H89-93. In addition, the ribosomal A-loop of the mature 50S subunit from ΔrrmJ strain displays large local flexibility on nucleotides next to unmethylated U2552. Fast kinetics-based biochemical assays demonstrate that the ΔrrmJ 50S subunit is only 50% active and two times slower than the WT 50S subunit in rapid subunit association. While the ΔrrmJ 70S ribosomes show no defect in peptide bond formation, peptide release, and ribosome recycling, they translocate with 20% slower rate than the WT ribosomes in each round of elongation. These defects amplify during synthesis of the full-length proteins and cause overall defect in protein synthesis. In conclusion, our data reveal the molecular roles of U2552 methylation in both ribosome biogenesis and protein translation.
Asunto(s)
Escherichia coli/fisiología , Extensión de la Cadena Peptídica de Translación , Iniciación de la Cadena Peptídica Traduccional , ARN Ribosómico 23S/metabolismo , Subunidades Ribosómicas Grandes Bacterianas/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Microscopía por Crioelectrón , Técnicas de Inactivación de Genes , Metilación , Metiltransferasas/genética , Metiltransferasas/metabolismo , Modelos Moleculares , Subunidades Ribosómicas Grandes Bacterianas/genética , Subunidades Ribosómicas Grandes Bacterianas/ultraestructura , Uridina/metabolismoRESUMEN
CDK4/6 were attractive chemotherapeutic targets for the treatment of malignant tumors, CDK4/6 selective inhibitors have made outstanding contributions in the treatment of breast cancer. However, these inhibitors share a single skeleton of N-(pyridin-2-yl) pyrimidin-2-amine which cannot overcome the side effects in clinical application. In our previous study, an N'- acetylpyrrolidine-1-carbohydrazide was hit as the initial fragment by analyzing the active site characteristics of CDK6. Two series of N-(pyridin-3-yl) proline were obtained by fragment growth method. The QSAR study was carried out according to the in vitro activities data against CDK4/6, and two compounds 7c and 7p with potent inhibitory activities were found to interact with CDK4 in different binding conformation. They showed potential inhibition of cell proliferation against the breast cancer cell, and 7c exhibited promised anti-breast cancer effect in vivo.
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Antineoplásicos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Quinasa 4 Dependiente de la Ciclina/antagonistas & inhibidores , Quinasa 6 Dependiente de la Ciclina/antagonistas & inhibidores , Prolina/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Animales , Antineoplásicos/síntesis química , Antineoplásicos/química , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Quinasa 4 Dependiente de la Ciclina/metabolismo , Quinasa 6 Dependiente de la Ciclina/metabolismo , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Humanos , Células MCF-7 , Neoplasias Mamarias Experimentales/tratamiento farmacológico , Neoplasias Mamarias Experimentales/metabolismo , Neoplasias Mamarias Experimentales/patología , Ratones , Ratones Desnudos , Estructura Molecular , Prolina/síntesis química , Prolina/química , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/química , Relación Estructura-ActividadRESUMEN
DNA replication in eukaryotes is strictly regulated by several mechanisms. A central step in this replication is the assembly of the heterohexameric minichromosome maintenance (MCM2-7) helicase complex at replication origins during G1 phase as an inactive double hexamer. Here, using cryo-electron microscopy, we report a near-atomic structure of the MCM2-7 double hexamer purified from yeast G1 chromatin. Our structure shows that two single hexamers, arranged in a tilted and twisted fashion through interdigitated amino-terminal domain interactions, form a kinked central channel. Four constricted rings consisting of conserved interior ß-hairpins from the two single hexamers create a narrow passageway that tightly fits duplex DNA. This narrow passageway, reinforced by the offset of the two single hexamers at the double hexamer interface, is flanked by two pairs of gate-forming subunits, MCM2 and MCM5. These unusual features of the twisted and tilted single hexamers suggest a concerted mechanism for the melting of origin DNA that requires structural deformation of the intervening DNA.
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Microscopía por Crioelectrón , Proteínas de Mantenimiento de Minicromosoma/química , Proteínas de Mantenimiento de Minicromosoma/ultraestructura , Subunidades de Proteína/química , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/ultraestructura , Sitios de Unión , Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/ultraestructura , Cromatina/química , Secuencia Conservada , ADN/química , ADN/metabolismo , ADN/ultraestructura , ADN Polimerasa Dirigida por ADN/química , ADN Polimerasa Dirigida por ADN/ultraestructura , Fase G1 , Proteínas de Mantenimiento de Minicromosoma/metabolismo , Modelos Biológicos , Modelos Moleculares , Complejos Multienzimáticos/química , Complejos Multienzimáticos/ultraestructura , Desnaturalización de Ácido Nucleico , Unión Proteica , Multimerización de Proteína , Estructura Terciaria de Proteína , Subunidades de Proteína/metabolismo , Origen de Réplica , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/ultraestructuraRESUMEN
Piezo proteins are evolutionarily conserved and functionally diverse mechanosensitive cation channels. However, the overall structural architecture and gating mechanisms of Piezo channels have remained unknown. Here we determine the cryo-electron microscopy structure of the full-length (2,547 amino acids) mouse Piezo1 (Piezo1) at a resolution of 4.8 Å. Piezo1 forms a trimeric propeller-like structure (about 900 kilodalton), with the extracellular domains resembling three distal blades and a central cap. The transmembrane region has 14 apparently resolved segments per subunit. These segments form three peripheral wings and a central pore module that encloses a potential ion-conducting pore. The rather flexible extracellular blade domains are connected to the central intracellular domain by three long beam-like structures. This trimeric architecture suggests that Piezo1 may use its peripheral regions as force sensors to gate the central ion-conducting pore.
Asunto(s)
Microscopía por Crioelectrón , Canales Iónicos/química , Canales Iónicos/ultraestructura , Animales , Membrana Celular/metabolismo , Conductividad Eléctrica , Activación del Canal Iónico , Canales Iónicos/metabolismo , Ratones , Modelos Moleculares , Docilidad , Multimerización de Proteína , Estructura Cuaternaria de Proteína , Estructura Terciaria de Proteína , Subunidades de Proteína/química , Subunidades de Proteína/metabolismoRESUMEN
The 5-year survival rate of lung cancer is one of the lowest among various malignant tumors. Long noncoding RNAs (lncRNAs), noncoding RNAs longer than 200 nucleotides, can function either as tumor suppressors or as oncogenes. The aim of this study is to investigate the function of lncRNA LINC01296 and its molecular mechanism in non-small-cell lung cancer (NSCLC). According to the Gene Expression Omnibus database, 10 differentially expressed lncRNAs in NSCLC cells and patient tissues are upregulated. LINC01296 is the one with the most significant overexpression. Knockdown of LINC01296 inhibits the growth and migration, arrests the cell cycle, and promotes the apoptosis of NSCLC cells. Knocking down LINC01296 in vivo suppresses tumor growth and metastasis. LINC01296 also acts as the sponge of miR-143-3p. Lowering the expression of LINC01296 leads to decreased expression of autophagy-related 2B (ATG2B), a target gene of miR-143-3p. Moreover, downregulation of LINC01296 promotes paclitaxel sensitivity in NSCLC. These results demonstrated that the LINC01296/miR-143-3p/ATG2B axis is crucial in promoting the development of NSCLC and paclitaxel resistance. Our study may provide new ideas for the further research of clinical chemotherapy of NSCLC in the near future.
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Proteínas Relacionadas con la Autofagia/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/genética , Neoplasias Pulmonares/genética , MicroARNs/metabolismo , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Animales , Apoptosis/genética , Proteínas Relacionadas con la Autofagia/genética , Ciclo Celular/genética , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Citoplasma/genética , Citoplasma/metabolismo , Regulación hacia Abajo , Resistencia a Antineoplásicos/genética , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Ratones Desnudos , Metástasis de la Neoplasia/genética , Paclitaxel/farmacología , Proteínas de Transporte Vesicular/genéticaRESUMEN
Monitoring regional terrestrial water load deformation is of great significance to the dynamic maintenance and hydrodynamic study of the regional benchmark framework. In view of the lack of a spatial interpolation method based on the GNSS (Global Navigation Satellite System) elevation time series for obtaining terrestrial water load deformation information, this paper proposes to employ a CORS (Continuously Operating Reference Stations) network combined with environmental loading data, such as ECMWF (European Centre for Medium-Range Weather Forecasts) atmospheric data, the GLDAS (Global Land Data Assimilation System) hydrological model, and MSLA (Mean Sea Level Anomaly) data. Based on the load deformation theory and spherical harmonic analysis method, we took 38 CORS stations in southeast Zhejiang province as an example and comprehensively determined the vertical deformation of the crust as caused by regional terrestrial water load changes from January 2015 to December 2017, and then compared these data with the GRACE (Gravity Recovery and Climate Experiment) satellite. The results show that the vertical deformation value of the terrestrial water load in southeast Zhejiang, as monitored by the CORS network, can reach a centimeter, and the amplitude changes from -1.8 cm to 2.4 cm. The seasonal change is obvious, and the spatial distribution takes a ladder form from inland to coastal regions. The surface vertical deformation caused by groundwater load changes in the east-west-south-north-central sub-regions show obvious fluctuations from 2015 to 2017, and the trends of the five sub-regions are consistent. The amplitude of surface vertical deformation caused by groundwater load change in the west is higher than that in the east. We tested the use of GRACE for the verification of CORS network monitoring results and found a relatively consistent temporal distribution between both data sets after phase delay correction on GRACE, except for in three months-November in 2015, and January and February in 2016. The results show that the comprehensive solution based on the CORS network can effectively improve the monitoring of crustal vertical deformation during regional terrestrial water load change.
RESUMEN
C-Met plays a crucial role in the development and progression of neoplastic disease. Type II c-Met inhibitors recognise the inactive DFG-out conformation of the kinase, result in better anti-tumour effects due to synergistic effect against the other kinases. According to our previous works, an (E)-N'-benzylidene group was selected as the initial fragment. Two series of (E)-N'-benzylidene hydrazides were designed by fragment growth method. The inhibitory activities were in vitro investigated against c-Met and VEGFR-2. Compound 10b exhibited the most potent inhibitory activity against the c-Met inhibitor (IC50 = 0.37 nM). Compound 11b exhibited multi-target c-Met kinase inhibitory activity as a potential type II c-Met inhibitor (IC50 = 3.41 nM against c-Met; 25.34 nM against VEGFR-2). The two compounds also demonstrate the feasibility of fragment-based virtual screening method for drug discovery.
Asunto(s)
Compuestos de Bencilideno/síntesis química , Compuestos de Bencilideno/farmacología , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas c-met/antagonistas & inhibidores , Compuestos de Bencilideno/química , Descubrimiento de Drogas , Humanos , Inhibidores de Proteínas Quinasas/química , Relación Estructura-Actividad Cuantitativa , Receptor 2 de Factores de Crecimiento Endotelial Vascular/antagonistas & inhibidoresRESUMEN
Cyclin-dependent kinase 2 (CDK2) is the family of Ser/Thr protein kinases that has emerged as a highly selective with low toxic cancer therapy target. A multistage virtual screening method combined by SVM, protein-ligand interaction fingerprints (PLIF) pharmacophore and docking was utilised for screening the CDK2 inhibitors. The evaluation of the validation set indicated that this method can be used to screen large chemical databases because it has a high hit-rate and enrichment factor (80.1% and 332.83 respectively). Six compounds were screened out from NCI, Enamine and Pubchem database. After molecular dynamics and binding free energy calculation, two compounds had great potential as novel CDK2 inhibitors and they also showed selective inhibition against CDK2 in the kinase activity assay.
Asunto(s)
Antineoplásicos/análisis , Antineoplásicos/farmacología , Quinasa 2 Dependiente de la Ciclina/antagonistas & inhibidores , Simulación del Acoplamiento Molecular , Inhibidores de Proteínas Quinasas/análisis , Inhibidores de Proteínas Quinasas/farmacología , Máquina de Vectores de Soporte , Células A549 , Antineoplásicos/química , Proliferación Celular/efectos de los fármacos , Quinasa 2 Dependiente de la Ciclina/metabolismo , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos , Ensayos de Selección de Medicamentos Antitumorales , Células HCT116 , Humanos , Estructura Molecular , Inhibidores de Proteínas Quinasas/química , Relación Estructura-ActividadRESUMEN
The terrestrial water storage anomaly (TWSA) gap between the Gravity Recovery and Climate Experiment (GRACE) and its follow-on mission (GRACE-FO) is now a significant issue for scientific research in high-resolution time-variable gravity fields. This paper proposes the use of singular spectrum analysis (SSA) to predict the TWSA derived from GRACE. We designed a case study in six regions in China (North China Plain (NCP), Southwest China (SWC), Three-River Headwaters Region (TRHR), Tianshan Mountains Region (TSMR), Heihe River Basin (HRB), and Lishui and Wenzhou area (LSWZ)) using GRACE RL06 data from January 2003 to August 2016 for inversion, which were compared with Center for Space Research (CSR), Helmholtz-Centre Potsdam-German Research Centre for Geosciences (GFZ), Jet Propulsion Laboratory (JPL)'s Mascon (Mass Concentration) RL05, and JPL's Mascon RL06. We evaluated the accuracy of SSA prediction on different temporal scales based on the correlation coefficient (R), Nash-Sutcliffe efficiency (NSE), and root mean square error (RMSE), which were compared with that of an auto-regressive and moving average (ARMA) model. The TWSA from September 2016 to May 2019 were predicted using SSA, which was verified using Mascon RL06, the Global Land Data Assimilation System model, and GRACE-FO results. The results show that: (1) TWSA derived from GRACE agreed well with Mascon in most regions, with the highest consistency with Mascon RL06 and (2) prediction accuracy of GRACE in TRHR and SWC was higher. SSA reconstruction improved R, NSE, and RMSE compared with those of ARMA. The R values for predicting TWS in the six regions using the SSA method were 0.34-0.98, which was better than those for ARMA (0.26-0.97), and the RMSE values were 0.03-5.55 cm, which were better than the 2.29-5.11 cm RMSE for ARMA as a whole. (3) The SSA method produced better predictions for obvious periodic and trending characteristics in the TWSA in most regions, whereas the detailed signal could not be effectively predicted. (4) The predicted TWSA from September 2016 to May 2019 were basically consistent with Global Land Data Assimilation System (GLDAS) results, and the predicted TWSA during June 2018 to May 2019 agreed well with GRACE-FO results. The research method in this paper provides a reference for bridging the gap in the TWSA between GRACE and GRACE-FO.
RESUMEN
Phosphoinositide 3 kinase delta (PI3Kδ) is a lipid kinase that has been implicated in a variety of immune mediated disorders. The research on isoform selectivity was crucial for reducing side effects. In the current study, an optimized hierarchical multistage virtual screening method was utilized for screening the PI3Kδ selective inhibitors. The method sequentially applied a support vector machine (SVM), a protein ligand interaction fingerprint (PLIF) pharmacophore, and a molecular docking approach. The evaluation of the validation set showed a high hit rate and a high enrichment factor of 75.1% and 301.66, respectively. This multistage virtual screening method was then utilized to screen the NCI database. From the final hit list, Compound 10 has great potential as the PI3Kδ inhibitor with micromolar inhibition in the PI3Kδ kinase activity assay. This compound also shows selectivity against PI3Kδ kinase. The method combining SVM, pharmacophore, and docking was capable of screening out the compounds with potential PI3Kδ selective inhibitors. Moreover, structural modification of Compound 10 will contribute to investigating the novel scaffold and designing novel PI3Kδ inhibitors.
Asunto(s)
Fosfatidilinositol 3-Quinasa Clase I/antagonistas & inhibidores , Simulación del Acoplamiento Molecular , Inhibidores de Proteínas Quinasas/farmacología , Bibliotecas de Moléculas Pequeñas/farmacología , Fosfatidilinositol 3-Quinasa Clase I/química , Fosfatidilinositol 3-Quinasa Clase I/metabolismo , Descubrimiento de Drogas/métodos , Humanos , Inhibidores de Proteínas Quinasas/química , Bibliotecas de Moléculas Pequeñas/química , Máquina de Vectores de SoporteRESUMEN
Individuals diagnosed with head and neck squamous cell carcinoma (HNSCC) experience a significant occurrence rate and are susceptible to premature spreading, resulting in a bleak outlook. Therapeutic approaches, such as chemotherapy, targeted therapy, and immunotherapy, may exhibit primary and acquired resistance during the advanced phases of HNSCC. There is currently no viable solution to tackle this issue. PANoptosis-a type of non-apoptotic cell death-is a recently identified mechanism of cellular demise that entails communication and synchronization among thermal apoptosis, apoptosis, and necrosis mechanisms. However, the extent to which PANoptosis-associated genes (PRG) contribute to the forecast and immune reaction of HNSCC remains mostly undisclosed. The present study aimed to thoroughly analyze the potential importance of PRG in HNSCC and report our discoveries. We systematically analyzed 19 PRG from previous studies and clinical data from HNSCC patients to establish a PAN-related signature and assess its prognostic, predictive potential. Afterward, the patient information was separated into two gene patterns that corresponded to each other, and the analysis focused on the connection between patient prognosis, immune status, and cancer immunotherapy. The PAN score was found to correlate with survival rates, immune systems, and cancer-related pathways. We then validated the malignant role of CD27 among them in HNSCC. In summary, we demonstrated the effectiveness of PAN.Score-based molecular clustering and prognostic features in predicting the outcome of HNSCC. The discovery we made could enhance our comprehension of the significance of PAN.Score in HNSCC and facilitate the development of more effective treatment approaches.
RESUMEN
Monitoring and predicting the regional groundwater storage (GWS) fluctuation is an essential support for effectively managing water resources. Therefore, taking Shandong Province as an example, the data from Gravity Recovery and Climate Experiment (GRACE) and GRACE Follow-On (GRACE-FO) is used to invert GWS fluctuation from January 2003 to December 2022 together with Watergap Global Hydrological Model (WGHM), in-situ groundwater volume and level data. The spatio-temporal characteristics are decomposed using Independent Components Analysis (ICA), and the impact factors, such as precipitation and human activities, which are also analyzed. To predict the short-time changes of GWS, the Support Vector Machines (SVM) is adopted together with three commonly used methods Long Short-Term Memory (LSTM), Singular Spectrum Analysis (SSA), Auto-Regressive Moving Average Model (ARMA), as the comparison. The results show that: (1) The loss intensity of western GWS is significantly greater than those in coastal areas. From 2003 to 2006, GWS increased sharply; during 2007 to 2014, there exists a loss rate - 5.80 ± 2.28 mm/a of GWS; the linear trend of GWS change is - 5.39 ± 3.65 mm/a from 2015 to 2022, may be mainly due to the effect of South-to-North Water Diversion Project. The correlation coefficient between GRACE and WGHM is 0.67, which is consistent with in-situ groundwater volume and level. (2) The GWS has higher positive correlation with monthly Global Precipitation Climatology Project (GPCP) considering time delay after moving average, which has the similar energy spectrum depending on Continuous Wavelet Transform (CWT) method. In addition, the influencing facotrs on annual GWS fluctuation are analyzed, the correlation coefficient between GWS and in-situ data including the consumption of groundwater mining, farmland irrigation is 0.80, 0.71, respectively. (3) For the GWS prediction, SVM method is adopted to analyze, three training samples with 180, 204 and 228 months are established with the goodness-of-fit all higher than 0.97. The correlation coefficients are 0.56, 0.75, 0.68; RMSE is 5.26, 4.42, 5.65 mm; NSE is 0.28, 0.43, 0.36, respectively. The performance of SVM model is better than the other methods for the short-term prediction.
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Accurate prediction of regional terrestrial water storage change (TWSA) is of great significance for water resources planning and management, and early warning of extreme climate disasters. Aiming at the problem that the conventional methods on prediction of TWSA time series are difficult to be accurate, the six typical regions are selected in China as examples, including the upper reaches of the Yangtze River (UYR), the southwest region (SWR), the Liaohe River Basin (LRB), the North China Plain (NCP), the Qinghai-Tibet Plateau (QTP), and the Pearl River Basin (PRB). The mascon product from GRACE/GRACE-FO provided by CSR is used to extract TWSA time series in six typical areas. The improved Back Propagation (BP) neural network, Long Short-Term Memory (LSTM) neural network and the latest Bidirectional LSTM (BiLSTM-attention) neural network model based on attention mechanism are proposed to predict and analyze the regional TWSA. In the experiment, the selection of the optimal model parameters such as the number of hidden layer nodes and the number of hidden units of the neural network model is tested and analyzed in detail. Meanwhile, the model prediction results are compared with the traditional least squares method and random forest (RF) prediction method. The root mean square error (RMSE), determination coefficient (R2), Nash-Sutcliffe efficiency coefficient (NSE) and mean absolute percentage error (MAPE) were used to evaluate the accuracy of the predicted results. The results show that the improved BP, LSTM and Bi-LSTM-attention neural network models all achieve higher prediction accuracy in UYR and SWR areas. RMSE is less than 2.641 cm, R2 is as high as 0.8 or more, NSE is above 0.6, and MAPE is within 0.1. Compared with the least square method, the RMSE of the predicted results from three neural network decreased by 0.998 cm, 0.700 cm and 0.7563 on average, and the R2 increased by 81.75%, 69.89% and 72% on average. Compared with RFML method, the RMSE from three neural network is reduced by 0.601 cm, 0.316 cm and 0.360, and R2 is increased by 38.20%, 24.60% and 27.06% on average. NSE and RMSE are improved to varying degrees in the above regions. It shows that the improved BP, LSTM and BiLSTM-attention model used can effectively predict TWSA. The research methods and results in this paper can provide important reference for the rational utilization of regional water resources and disaster risk assessment.
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OBJECTIVE: Inflammation serves as the initial pathologic step of cardiovascular diseases including atherosclerosis. Resveratrol possesses many pharmacological properties including antioxidant, cardioprotective and anti-cancer effects. In this study, we investigate the anti-inflammatory effect and mechanisms of resveratrol in an atherosclerotic rabbit model. METHODS: Rabbit were assigned to six groups (n = 10 each): control, high fat diet group, resveratrol low, medium and high dose groups, resveratrol pretreatment group. The serum tumor necrosis factor-α (TNF- α), interleukin-6 (IL-6) and interleukin-1ß (IL-1ß) were analyzed by Enzyme-linked immuno sorbent assay(ELISA). Phosphorylation levels of mitogen-activated protein kinases (MAPKs) cascades and NF-κB were determined by Western blot. RESULTS: Compared with the control group, the expression of serum inflammatory factors IL-1ß, IL-6, TNF-α were increased in high-fat group (all P < 0.05). Compared with high-fat group, the expressions of IL-6, IL-1ß, TNF-α were significantly reduced in resveratrol low, medium, high dose groups and resveratrol pretreatment group (all P < 0.01), and this effect is dose-dependent. In addition, the NF-κB, p38MAPK, JNK, ERK1/2 protein phosphorylation in high-fat group were significantly upregulated compared with control group (P < 0.05), which (except ERK1/2 phosphorylation level) were significantly downregulated in resveratrol treatment group and resveratrol pretreatment group. CONCLUSION: This study indicates that resveratrol reduces serum inflammatory cytokines in this atherosclerotic rabbit model via down-regulation phosphorylation of NF-κB, and MAPKs signaling, which might serve as the anti-inflammatory molecular basis of resveratrol.
Asunto(s)
Aterosclerosis/metabolismo , Transducción de Señal/efectos de los fármacos , Estilbenos/farmacología , Animales , Aterosclerosis/tratamiento farmacológico , Modelos Animales de Enfermedad , Interleucina-1beta/sangre , Interleucina-6/sangre , Masculino , Proteínas Quinasas Activadas por Mitógenos/metabolismo , FN-kappa B/metabolismo , Fosforilación , Conejos , Resveratrol , Estilbenos/uso terapéutico , Factor de Necrosis Tumoral alfa/sangreRESUMEN
Histone lysine methyltransferase SUV420H1, which is responsible for site-specific di-/tri-methylation of histone H4 lysine 20 (H4K20), has crucial roles in DNA-templated processes, including DNA replication, DNA damage repair, and chromatin compaction. Its mutations frequently occur in human cancers. Nucleosomes containing the histone variant H2A.Z enhance the catalytic activities of SUV420H1 on H4K20 di-methylation deposition, regulating early replication origins. However, the molecular mechanism by which SUV420H1 specifically recognizes and deposits H4K20 methyl marks on nucleosomes remains poorly understood. Here we report the cryo-electron microscopy structures of SUV420H1 associated with H2A-containing nucleosome core particles (NCPs), and H2A.Z-containing NCPs. We find that SUV420H1 makes extensive site-specific contacts with histone and DNA regions. SUV420H1 C-terminal domain recognizes the H2A-H2B acidic patch of NCPs through its two arginine anchors, thus enabling H4K20 insertion for catalysis specifically. We also identify important residues increasing the catalytic activities of SUV420H1 bound to H2A.Z NCPs. In vitro and in vivo functional analyses reveal that multiple disease-associated mutations at the interfaces are essential for its catalytic activity and chromatin state regulation. Together, our study provides molecular insights into the nucleosome-based recognition and methylation mechanisms of SUV420H1, and a structural basis for understanding SUV420H1-related human disease.
RESUMEN
Renal dysfunction is a common complication of sepsis. Early diagnosis and prompt treatment of sepsis with renal insufficiency are crucial for improving patient outcomes. Diagnostic markers can help identify patients at risk for sepsis and AKI, allowing for early intervention and potentially preventing the development of severe complications. The aim of the present study was to investigate the expression difference of urinary microRNAs (miRNAs/miRs) in elderly patients with sepsis and secondary renal insufficiency, and to evaluate their diagnostic value in these patients. In the present study, RNA was extracted from urine samples of elderly sepsis-related acute renal damage patients and the expression profiles of several miRNAs were analyzed. In order to evaluate the expression profile of several miRNAs, urine samples from elderly patients with acute renal damage brought on by sepsis were obtained. RNA extraction and sequencing were then performed on the samples. Furthermore, multiple bioinformatics methods were used to analyze miRNA profiles, including differential expression analysis, and Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analysis of different miRNA target genes, to further explore miRNAs that are suitable for utilization as biomarkers. A total of four miRNAs, including hsa-miR-31-5p, hsa-miR-151a-3p, hsa-miR-142-5p and hsa-miR-16-5p, were identified as potential biological markers and were further confirmed in sepsis using reverse transcription-quantitative PCR. The results of the present study demonstrated that the four urinary miRNAs were differentially expressed and may serve as specific markers for prediction of secondary acute kidney injury in elderly patients with sepsis.
RESUMEN
Diabetic foot ulcers are seriously endangering the physical and mental health of patients. Due to the long duration of inflammation, the treatment of nonhealing wounds in diabetes is one of the most prominent healthcare problems in the world. The nuclear factor kappa B (NF-κB) signaling pathway, a classical pathway that triggers inflammatory response, is regulated by many regulators, such as glycogen synthase kinase 3 beta (GSK-3ß). Noncoding RNAs, a large class of molecules that regulate gene expression at the posttranscriptional or posttranslational level, play an important role in various stages of wound healing, especially in the stage of inflammation. Herein, we summarized the roles of noncoding RNAs in the NF-κB/GSK-3ß signaling, which might provide new ideas for the treatment of diabetic wound healing.