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1.
EMBO J ; 42(10): e113320, 2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-37066886

RESUMO

The eukaryotic vacuolar transporter chaperone (VTC) complex acts as a polyphosphate (polyP) polymerase that synthesizes polyP from adenosine triphosphate (ATP) and translocates polyP across the vacuolar membrane to maintain an intracellular phosphate (Pi ) homeostasis. To discover how the VTC complex performs its function, we determined a cryo-electron microscopy structure of an endogenous VTC complex (Vtc4/Vtc3/Vtc1) purified from Saccharomyces cerevisiae at 3.1 Å resolution. The structure reveals a heteropentameric architecture of one Vtc4, one Vtc3, and three Vtc1 subunits. The transmembrane region forms a polyP-selective channel, likely adopting a resting state conformation, in which a latch-like, horizontal helix of Vtc4 limits the entrance. The catalytic Vtc4 central domain is located on top of the pseudo-symmetric polyP channel, creating a strongly electropositive pathway for nascent polyP that can couple synthesis to translocation. The SPX domain of the catalytic Vtc4 subunit positively regulates polyP synthesis by the VTC complex. The noncatalytic Vtc3 regulates VTC through a phosphorylatable loop. Our findings, along with the functional data, allow us to propose a mechanism of polyP channel gating and VTC complex activation.


Assuntos
Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Microscopia Crioeletrônica , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Vacúolos/metabolismo , Polifosfatos/metabolismo
2.
Brief Bioinform ; 25(3)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38557672

RESUMO

Lung adenocarcinoma (LUAD) is the most common histologic subtype of lung cancer. Early-stage patients have a 30-50% probability of metastatic recurrence after surgical treatment. Here, we propose a new computational framework, Interpretable Biological Pathway Graph Neural Networks (IBPGNET), based on pathway hierarchy relationships to predict LUAD recurrence and explore the internal regulatory mechanisms of LUAD. IBPGNET can integrate different omics data efficiently and provide global interpretability. In addition, our experimental results show that IBPGNET outperforms other classification methods in 5-fold cross-validation. IBPGNET identified PSMC1 and PSMD11 as genes associated with LUAD recurrence, and their expression levels were significantly higher in LUAD cells than in normal cells. The knockdown of PSMC1 and PSMD11 in LUAD cells increased their sensitivity to afatinib and decreased cell migration, invasion and proliferation. In addition, the cells showed significantly lower EGFR expression, indicating that PSMC1 and PSMD11 may mediate therapeutic sensitivity through EGFR expression.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Humanos , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/metabolismo , Neoplasias Pulmonares/metabolismo , Linhagem Celular Tumoral , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Regulação Neoplásica da Expressão Gênica , Receptores ErbB/genética , Proliferação de Células
3.
Brief Bioinform ; 25(3)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38678587

RESUMO

Deep learning-based multi-omics data integration methods have the capability to reveal the mechanisms of cancer development, discover cancer biomarkers and identify pathogenic targets. However, current methods ignore the potential correlations between samples in integrating multi-omics data. In addition, providing accurate biological explanations still poses significant challenges due to the complexity of deep learning models. Therefore, there is an urgent need for a deep learning-based multi-omics integration method to explore the potential correlations between samples and provide model interpretability. Herein, we propose a novel interpretable multi-omics data integration method (DeepKEGG) for cancer recurrence prediction and biomarker discovery. In DeepKEGG, a biological hierarchical module is designed for local connections of neuron nodes and model interpretability based on the biological relationship between genes/miRNAs and pathways. In addition, a pathway self-attention module is constructed to explore the correlation between different samples and generate the potential pathway feature representation for enhancing the prediction performance of the model. Lastly, an attribution-based feature importance calculation method is utilized to discover biomarkers related to cancer recurrence and provide a biological interpretation of the model. Experimental results demonstrate that DeepKEGG outperforms other state-of-the-art methods in 5-fold cross validation. Furthermore, case studies also indicate that DeepKEGG serves as an effective tool for biomarker discovery. The code is available at https://github.com/lanbiolab/DeepKEGG.


Assuntos
Biomarcadores Tumorais , Aprendizado Profundo , Recidiva Local de Neoplasia , Humanos , Biomarcadores Tumorais/metabolismo , Biomarcadores Tumorais/genética , Recidiva Local de Neoplasia/metabolismo , Recidiva Local de Neoplasia/genética , Biologia Computacional/métodos , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Genômica/métodos , Multiômica
4.
Brief Bioinform ; 24(1)2023 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-36611256

RESUMO

Accumulating evidences demonstrate that circular RNA (circRNA) plays an important role in human diseases. Identification of circRNA-disease associations can help for the diagnosis of human diseases, while the traditional method based on biological experiments is time-consuming. In order to address the limitation, a series of computational methods have been proposed in recent years. However, few works have summarized these methods or compared the performance of them. In this paper, we divided the existing methods into three categories: information propagation, traditional machine learning and deep learning. Then, the baseline methods in each category are introduced in detail. Further, 5 different datasets are collected, and 14 representative methods of each category are selected and compared in the 5-fold, 10-fold cross-validation and the de novo experiment. In order to further evaluate the effectiveness of these methods, six common cancers are selected to compare the number of correctly identified circRNA-disease associations in the top-10, top-20, top-50, top-100 and top-200. In addition, according to the results, the observation about the robustness and the character of these methods are concluded. Finally, the future directions and challenges are discussed.


Assuntos
Neoplasias , RNA Circular , Humanos , RNA Circular/genética , Benchmarking , Aprendizado de Máquina , Neoplasias/genética , Biologia Computacional/métodos
5.
Nat Chem Biol ; 19(10): 1276-1285, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37550431

RESUMO

Phe-Met-Arg-Phe-amide (FMRFamide)-activated sodium channels (FaNaCs) are a family of channels activated by the neuropeptide FMRFamide, and, to date, the underlying ligand gating mechanism remains unknown. Here we present the high-resolution cryo-electron microscopy structures of Aplysia californica FaNaC in both apo and FMRFamide-bound states. AcFaNaC forms a chalice-shaped trimer and possesses several notable features, including two FaNaC-specific insertion regions, a distinct finger domain and non-domain-swapped transmembrane helix 2 in the transmembrane domain (TMD). One FMRFamide binds to each subunit in a cleft located in the top-most region of the extracellular domain, with participation of residues from the neighboring subunit. Bound FMRFamide adopts an extended conformation. FMRFamide binds tightly to A. californica FaNaC in an N terminus-in manner, which causes collapse of the binding cleft and induces large local conformational rearrangements. Such conformational changes are propagated downward toward the TMD via the palm domain, possibly resulting in outward movement of the TMD and dilation of the ion conduction pore.


Assuntos
Ativação do Canal Iônico , Neuropeptídeos , FMRFamida/metabolismo , FMRFamida/farmacologia , Microscopia Crioeletrônica , Neuropeptídeos/metabolismo , Canais de Sódio/química , Canais de Sódio/metabolismo
6.
Mol Ther ; 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38946142

RESUMO

The chimeric antigen receptor (CAR) derived from the CD30 specific murine antibody, HRS-3, has produced promising clinical efficacy with a favorable safety profile in the treatment of relapsed or refractory CD30-positive lymphomas. However, persistence of the autologous CAR T cells was brief, and many patients relapsed a year after treatment. The lack of persistence may be attributed to the use of a wildtype IgG1 spacer that can associate with Fc receptors. We first identified the cysteine rich domain (CRD) 5 of CD30 as the primary binding epitope of HRS-3 and armed with this insight, attempted to improve the HRS-3 CAR functionality with a panel of novel spacer designs. We demonstrate that HRS-3 CARs with OX40 and 4-1BB derived spacers exhibited similar anti-tumor efficacy, circumvented interactions with Fc receptors and secreted lower levels of cytokines in vitro than a CAR employing the IgG1 spacer. Humanization of the HRS-3 scFv coupled with the 4-1BB spacer preserved potent on-target, on-tumor efficacy, and on-target, off-tumor safety. In a lymphoma mouse model of high tumor burden, T cells expressing a humanized HRS-3 CD30.CARs with the 4-1BB spacer potently killed tumors with low levels of circulating inflammatory cytokines, providing a promising candidate for future clinical development in the treatment of CD30-positive malignancies.

7.
Proc Natl Acad Sci U S A ; 119(31): e2201376119, 2022 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-35878022

RESUMO

Relapse to anti-HER2 monoclonal antibody (mAb) therapies, such as trastuzumab in HER2+ breast cancer (BC), is associated with residual disease progression due to resistance to therapy. Here, we identify interferon-γ inducible protein 16 (IFI16)-dependent STING signaling as a significant determinant of trastuzumab responses in HER2+ BC. We show that down-regulation of immune-regulated genes (IRG) is specifically associated with poor survival of HER2+, but not other BC subtypes. Among IRG, IFI16 is identified as a direct target of EZH2, the underexpression of which leads to deficient STING activation and downstream CXCL10/11 expression in response to trastuzumab treatment. Dual inhibition of EZH2 and histone deacetylase (HDAC) significantly activates IFI16-dependent immune responses to trastuzumab. Notably, a combination of a novel histone methylation inhibitor with an HDAC inhibitor induces complete tumor eradication and long-term T cell memory in a HER2+ BC mouse model. Our findings demonstrate an epigenetic regulatory mechanism suppressing the expression of the IFI16-CXCL10/11 signaling pathway that provides a survival advantage to HER2+ BC to confer resistance to trastuzumab treatment.


Assuntos
Neoplasias da Mama , Resistencia a Medicamentos Antineoplásicos , Proteínas de Membrana , Proteínas Nucleares , Fosfoproteínas , Trastuzumab , Animais , Antineoplásicos Imunológicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/imunologia , Linhagem Celular Tumoral , Quimiocina CXCL10 , Quimiocina CXCL11 , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Imunidade , Proteínas de Membrana/metabolismo , Camundongos , Recidiva Local de Neoplasia/genética , Proteínas Nucleares/metabolismo , Fosfoproteínas/metabolismo , Receptor ErbB-2/genética , Transdução de Sinais , Trastuzumab/farmacologia
8.
J Cell Mol Med ; 28(7): e18224, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38509739

RESUMO

Drug-target interaction (DTI) prediction is essential for new drug design and development. Constructing heterogeneous network based on diverse information about drugs, proteins and diseases provides new opportunities for DTI prediction. However, the inherent complexity, high dimensionality and noise of such a network prevent us from taking full advantage of these network characteristics. This article proposes a novel method, NGCN, to predict drug-target interactions from an integrated heterogeneous network, from which to extract relevant biological properties and association information while maintaining the topology information. It focuses on learning the topology representation of drugs and targets to improve the performance of DTI prediction. Unlike traditional methods, it focuses on learning the low-dimensional topology representation of drugs and targets via graph-based convolutional neural network. NGCN achieves substantial performance improvements over other state-of-the-art methods, such as a nearly 1.0% increase in AUPR value. Moreover, we verify the robustness of NGCN through benchmark tests, and the experimental results demonstrate it is an extensible framework capable of combining heterogeneous information for DTI prediction.


Assuntos
Desenho de Fármacos , Redes Neurais de Computação
9.
BMC Genomics ; 25(1): 86, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38254021

RESUMO

BACKGROUND AND OBJECTIVES: Comprehensive analysis of multi-omics data is crucial for accurately formulating effective treatment plans for complex diseases. Supervised ensemble methods have gained popularity in recent years for multi-omics data analysis. However, existing research based on supervised learning algorithms often fails to fully harness the information from unlabeled nodes and overlooks the latent features within and among different omics, as well as the various associations among features. Here, we present a novel multi-omics integrative method MOSEGCN, based on the Transformer multi-head self-attention mechanism and Graph Convolutional Networks(GCN), with the aim of enhancing the accuracy of complex disease classification. MOSEGCN first employs the Transformer multi-head self-attention mechanism and Similarity Network Fusion (SNF) to separately learn the inherent correlations of latent features within and among different omics, constructing a comprehensive view of diseases. Subsequently, it feeds the learned crucial information into a self-ensembling Graph Convolutional Network (SEGCN) built upon semi-supervised learning methods for training and testing, facilitating a better analysis and utilization of information from multi-omics data to achieve precise classification of disease subtypes. RESULTS: The experimental results show that MOSEGCN outperforms several state-of-the-art multi-omics integrative analysis approaches on three types of omics data: mRNA expression data, microRNA expression data, and DNA methylation data, with accuracy rates of 83.0% for Alzheimer's disease and 86.7% for breast cancer subtyping. Furthermore, MOSEGCN exhibits strong generalizability on the GBM dataset, enabling the identification of important biomarkers for related diseases. CONCLUSION: MOSEGCN explores the significant relationship information among different omics and within each omics' latent features, effectively leveraging labeled and unlabeled information to further enhance the accuracy of complex disease classification. It also provides a promising approach for identifying reliable biomarkers, paving the way for personalized medicine.


Assuntos
Doença de Alzheimer , Multiômica , Humanos , Metilação de DNA , Algoritmos , Biomarcadores
10.
Brief Bioinform ; 23(1)2022 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-34864877

RESUMO

Increasing evidences have proved that circRNA plays a significant role in the development of many diseases. In addition, many researches have shown that circRNA can be considered as the potential biomarker for clinical diagnosis and treatment of disease. Some computational methods have been proposed to predict circRNA-disease associations. However, the performance of these methods is limited as the sparsity of low-order interaction information. In this paper, we propose a new computational method (KGANCDA) to predict circRNA-disease associations based on knowledge graph attention network. The circRNA-disease knowledge graphs are constructed by collecting multiple relationship data among circRNA, disease, miRNA and lncRNA. Then, the knowledge graph attention network is designed to obtain embeddings of each entity by distinguishing the importance of information from neighbors. Besides the low-order neighbor information, it can also capture high-order neighbor information from multisource associations, which alleviates the problem of data sparsity. Finally, the multilayer perceptron is applied to predict the affinity score of circRNA-disease associations based on the embeddings of circRNA and disease. The experiment results show that KGANCDA outperforms than other state-of-the-art methods in 5-fold cross validation. Furthermore, the case study demonstrates that KGANCDA is an effective tool to predict potential circRNA-disease associations.


Assuntos
MicroRNAs , RNA Circular , Biologia Computacional/métodos , MicroRNAs/genética , Redes Neurais de Computação , Reconhecimento Automatizado de Padrão
11.
EMBO Rep ; 23(6): e54271, 2022 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-35403791

RESUMO

The top cause of mortality in patients with nonalcoholic fatty liver disease (NAFLD) is cardiovascular complications. However, mechanisms of NAFLD-associated vasculopathy remain understudied. Here, we show that blood outgrowth endothelial cells (BOECs) from NAFLD subjects exhibit global transcriptional upregulation of chemokines and human leukocyte antigens. In mouse models of diet-induced NAFLD, we confirm heightened endothelial expressions of CXCL12 in the aortas and the liver vasculatures, and increased retention of infiltrated leukocytes within the vessel walls. To elucidate endothelial-immune crosstalk, we performed immunoprofiling by single-cell analysis, uncovering T cell intensification in NAFLD patients. Functionally, treatment with a CXCL12-neutralizing antibody is effective at moderating the enhanced chemotactic effect of NAFLD BOECs in recruiting CD8+ T lymphocytes. Interference with the CXCL12-CXCR4 axis using a CXCR4 antagonist also averts the impact of immune cell transendothelial migration and restores endothelial barrier integrity. Clinically, we detect threefold more circulating damaged endothelial cells in NAFLD patients than in healthy controls. Our work provides insight into the modulation of interactions with effector immune cells to mitigate endothelial injury in NAFLD.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Animais , Movimento Celular , Células Endoteliais/metabolismo , Humanos , Fígado/metabolismo , Linfócitos/metabolismo , Camundongos , Hepatopatia Gordurosa não Alcoólica/metabolismo , Transdução de Sinais
12.
Nature ; 556(7699): 130-134, 2018 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-29562233

RESUMO

The organellar two-pore channel (TPC) functions as a homodimer, in which each subunit contains two homologous Shaker-like six-transmembrane (6-TM)-domain repeats. TPCs belong to the voltage-gated ion channel superfamily and are ubiquitously expressed in animals and plants. Mammalian TPC1 and TPC2 are localized at the endolysosomal membrane, and have critical roles in regulating the physiological functions of these acidic organelles. Here we present electron cryo-microscopy structures of mouse TPC1 (MmTPC1)-a voltage-dependent, phosphatidylinositol 3,5-bisphosphate (PtdIns(3,5)P2)-activated Na+-selective channel-in both the apo closed state and ligand-bound open state. Combined with functional analysis, these structures provide comprehensive structural insights into the selectivity and gating mechanisms of mammalian TPC channels. The channel has a coin-slot-shaped ion pathway in the filter that defines the selectivity of mammalian TPCs. Only the voltage-sensing domain from the second 6-TM domain confers voltage dependence on MmTPC1. Endolysosome-specific PtdIns(3,5)P2 binds to the first 6-TM domain and activates the channel under conditions of depolarizing membrane potential. Structural comparisons between the apo and PtdIns(3,5)P2-bound structures show the interplay between voltage and ligand in channel activation. These MmTPC1 structures reveal lipid binding and regulation in a 6-TM voltage-gated channel, which is of interest in light of the emerging recognition of the importance of phosphoinositide regulation of ion channels.


Assuntos
Canais de Cálcio/metabolismo , Canais de Cálcio/ultraestrutura , Microscopia Crioeletrônica , Ativação do Canal Iônico/efeitos dos fármacos , Fosfolipídeos/farmacologia , Sequência de Aminoácidos , Animais , Canais de Cálcio/química , Canais de Cálcio/genética , Células HEK293 , Humanos , Camundongos , Modelos Moleculares , Fosfolipídeos/química , Fosfolipídeos/metabolismo , Domínios Proteicos/efeitos dos fármacos
13.
Brief Bioinform ; 22(6)2021 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-34121111

RESUMO

The rapid spread and huge impact of the COVID-19 pandemic caused by the emerging SARS-CoV-2 have driven large efforts for sequencing and analyzing the viral genomes. Mutation analyses have revealed that the virus keeps mutating and shows a certain degree of genetic diversity, which could result in the alteration of its infectivity and pathogenicity. Therefore, appropriate delineation of SARS-CoV-2 genetic variants enables us to understand its evolution and transmission patterns. By focusing on the nucleotides that co-substituted, we first identified 42 co-mutation modules that consist of at least two co-substituted nucleotides during the SARS-CoV-2 evolution. Then based on these co-mutation modules, we classified the SARS-CoV-2 population into 43 groups and further identified the phylogenetic relationships among groups based on the number of inconsistent co-mutation modules, which were validated with phylogenetic trees. Intuitively, we tracked tempo-spatial patterns of the 43 groups, of which 11 groups were geographic-specific. Different epidemic periods showed specific co-circulating groups, where the dominant groups existed and had multiple sub-groups of parallel evolution. Our work enables us to capture the evolution and transmission patterns of SARS-CoV-2, which can contribute to guiding the prevention and control of the COVID-19 pandemic. An interactive website for grouping SARS-CoV-2 genomes and visualizing the spatio-temporal distribution of groups is available at https://www.jianglab.tech/cmm-grouping/.


Assuntos
COVID-19/genética , Evolução Molecular , Genoma Viral/genética , SARS-CoV-2/genética , COVID-19/virologia , Variação Genética/genética , Humanos , Mutação/genética , Pandemias , Filogenia , SARS-CoV-2/patogenicidade , Sequenciamento Completo do Genoma
14.
Toxicol Appl Pharmacol ; 477: 116672, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37648089

RESUMO

Sepsis-induced cardiomyopathy (SIC) has high morbidity and mortality. Quercetin (QUE) has been used to treat many inflammatory diseases related to pyroptosis. However, its effect on SIC has not been reported before. We aimed to explore the therapeutic mechanism of QUE on SIC. We found that the expression levels of NOX2, markers of myocardial injury and inflammatory factors related to pyroptosis were upregulated in the serum of SIC patients. QUE improved the viability and reduced the death rate of LPS-treated H9C2 cells. It could downregulate the expression level of NOX2 and alleviate NOX2-induced mitochondrial damage to inhibit the ROS-mediated NF-κB/TXNIP pathway thus ameliorating cell pyroptosis. Overexpression of NOX2 partially attenuated the anti-pyroptotic effects of QUE on LPS-treated H9C2 cells in vitro. Besides, the results of animal experiments reported that the mitochondrial damage was reduced by QUE treatment, which subsequently inhibited the ROS-mediated NF-κB/TXNIP pathway to ameliorate cell pyroptosis to further alleviate myocardial injury in CLP-induced rats in vivo. To conclude, QUE suppressed the NOX2/ROS-mediated NF-κB/TXNIP signaling pathway to ameliorate pyroptosis of cardiomyocytes to relieve SIC.

15.
Inflamm Res ; 72(5): 989-1000, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37004547

RESUMO

BACKGROUND AND OBJECTIVE: COVID-19 infection poses a special challenge to patients with dialysis patients. The purpose of this study was to evaluate the clinical manifestations of dialysis patients with COVID-19 and the protective effect of the vaccine. METHODS: We included 41 studies based on big data, mainly analyzing the clinical symptoms of dialysis patients with COVID-19, the proportion of severe patients before and after vaccination, and the humoral reaction of vaccine in the body. RESULTS: 6.1% to 35.7% of dialysis patients with COVID-19 developed respiratory distress symptoms and needed to be admitted to an intensive care unit for mechanical ventilation. The incidence and mortality of COVID-19 in dialysis patients before vaccination were 5.5% and 1.1%, respectively, and decreased to 4.5% and 0.6% in breakthrough infected patients. There was no statistical difference in serum conversion rates between dialysis patients and healthy controls, but the neutralizing antibody titer in the control group was 1922 (IQR 533 to 3186) AU/mL, and the neutralizing antibody titer in dialysis patients significantly decreased to 367 (IQR 171 to 1650) AU/mL (P=0.046). CONCLUSIONS: Dialysis is associated with an increased risk of severe COVID-19, and generally has a poor seroconversion response to vaccines. It also confirms the protective effect of vaccines on high-risk populations such as dialysis.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Humanos , COVID-19/prevenção & controle , Diálise Renal , Vacinação , Anticorpos Neutralizantes
16.
Methods ; 208: 35-41, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36280134

RESUMO

Emerging studies have shown that circular RNA (circRNA) plays a significant role in the diagnosis and prognosis of human disease. Some computational methods have been proposed to predict circRNA-disease associations. However, some methods only use circRNA-disease association and ignore the associations of other biological entities. In addition, these methods do not take into account the latent factors of different kinds of circRNAs and diseases. To solve these limitations of existing computational models, we propose a new computational model (DRGCNCDA) based on disentangled relational graph convolutional network. The circRNA-disease multi-relational graphs are constructed by collecting multiple relational data among circRNA, disease, miRNA and lncRNA. Then, the disentangled relational graph convolutional network is employed to obtain the feature vectors of circRNA and disease. Finally, knowledge graph model is applied to predict the affinity scores of circRNA-disease associations based on the embeddings of circRNA and disease. The 5-fold cross validation is utilized to evaluate the performance of the method. The experimental results show that the DRGCNCDA outperforms other existing models. Moreover, the case study demonstrates that the DRGCNCDA is effective to predict the circRNA-disease association and can provide reliable candidates for biological experiments.


Assuntos
MicroRNAs , RNA Longo não Codificante , Humanos , RNA Circular/genética , Reconhecimento Automatizado de Padrão , MicroRNAs/genética , RNA Longo não Codificante/genética , Prognóstico , Biologia Computacional/métodos
17.
Nature ; 552(7684): 205-209, 2017 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-29211714

RESUMO

TRPM4 is a calcium-activated, phosphatidylinositol-4,5-bisphosphate (PtdIns(4,5)P2) -modulated, non-selective cation channel that belongs to the family of melastatin-related transient receptor potential (TRPM) channels. Here we present the electron cryo-microscopy structures of the mouse TRPM4 channel with and without ATP. TRPM4 consists of multiple transmembrane and cytosolic domains, which assemble into a three-tiered architecture. The N-terminal nucleotide-binding domain and the C-terminal coiled-coil participate in the tetrameric assembly of the channel; ATP binds at the nucleotide-binding domain and inhibits channel activity. TRPM4 has an exceptionally wide filter but is only permeable to monovalent cations; filter residue Gln973 is essential in defining monovalent selectivity. The S1-S4 domain and the post-S6 TRP domain form the central gating apparatus that probably houses the Ca2+- and PtdIns(4,5)P2-binding sites. These structures provide an essential starting point for elucidating the complex gating mechanisms of TRPM4 and reveal the molecular architecture of the TRPM family.


Assuntos
Microscopia Crioeletrônica , Canais de Cátion TRPM/ultraestrutura , Trifosfato de Adenosina/química , Trifosfato de Adenosina/metabolismo , Trifosfato de Adenosina/farmacologia , Animais , Sítios de Ligação , Cálcio/metabolismo , Camundongos , Modelos Moleculares , Domínios Proteicos , Estrutura Secundária de Proteína , Especificidade por Substrato , Canais de Cátion TRPM/antagonistas & inibidores , Canais de Cátion TRPM/química , Canais de Cátion TRPM/metabolismo
18.
Nature ; 550(7676): 415-418, 2017 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-29019981

RESUMO

Transient receptor potential mucolipin 1 (TRPML1) is a cation channel located within endosomal and lysosomal membranes. Ubiquitously expressed in mammalian cells, its loss-of-function mutations are the direct cause of type IV mucolipidosis, an autosomal recessive lysosomal storage disease. Here we present the single-particle electron cryo-microscopy structure of the mouse TRPML1 channel embedded in nanodiscs. Combined with mutagenesis analysis, the TRPML1 structure reveals that phosphatidylinositol-3,5-bisphosphate (PtdIns(3,5)P2) binds to the N terminus of the channel-distal from the pore-and the helix-turn-helix extension between segments S2 and S3 probably couples ligand binding to pore opening. The tightly packed selectivity filter contains multiple ion-binding sites, and the conserved acidic residues form the luminal Ca2+-blocking site that confers luminal pH and Ca2+ modulation on channel conductance. A luminal linker domain forms a fenestrated canopy atop the channel, providing several luminal ion passages to the pore and creating a negative electrostatic trap, with a preference for divalent cations, at the luminal entrance. The structure also reveals two equally distributed S4-S5 linker conformations in the closed channel, suggesting an S4-S5 linker-mediated PtdInsP2 gating mechanism among TRPML channels.


Assuntos
Microscopia Crioeletrônica , Endossomos/química , Lisossomos/química , Nanoestruturas/química , Canais de Potencial de Receptor Transitório/química , Canais de Potencial de Receptor Transitório/ultraestrutura , Animais , Sítios de Ligação , Cálcio , Concentração de Íons de Hidrogênio , Transporte de Íons , Ligantes , Camundongos , Modelos Moleculares , Mutação , Fosfatos de Fosfatidilinositol/metabolismo , Conformação Proteica , Eletricidade Estática , Canais de Potencial de Receptor Transitório/genética
19.
Environ Res ; 219: 115015, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36535391

RESUMO

Cr(VI) pollution is a growing problem that causes the deterioration of the environment and human health. We report the development of an effective adsorbent for the removal of Cr(VI) from wastewater. N-doped cellulose-based hydrothermal carbon (N-CHC) was prepared via a two-step hydrothermal method. The morphology and structural properties of N-CHC were investigated by various techniques. N-CHC has many O and N groups, which are suitable for Cr(VI) adsorption and reduction. Intermittent adsorption experiments showed that N-CHC had an adsorption capacity of 151.05 mg/g for Cr(VI) at pH 2, indicating excellent adsorption performance. Kinetic and thermodynamic analyses indicates that the adsorption of Cr(VI) on N-CHC follows a monolayer uniform adsorption process, which is a spontaneous endothermic process dominated by chemical interaction and limited by diffusion within particles. In a multi-ion system (Pb2+, Cd2+, Mn7+, Cl-, and SO42-), the selectivity of N-CHC toward Cr(VI) was 82.62%. In addition, N-CHC demonstrated excellent reuse performance over seven adsorption-desorption cycles; the Cr(VI) removal rate of N-CHC in 5-20 mg/L wastewater was >99.87%, confirming the potential of N-CHC for large-scale applications. CN/C-OR, pyridinic-N, and pyrrolic-N were found to play a critical role in the adsorption process. This study provides a new technology for Cr(VI) pollution control that could be utilized in large-scale production and other environmental applications.


Assuntos
Águas Residuárias , Poluentes Químicos da Água , Humanos , Carbono , Celulose , Cromo/análise , Adsorção , Poluentes Químicos da Água/análise , Concentração de Íons de Hidrogênio , Cinética
20.
Environ Res ; 237(Pt 1): 116917, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37611784

RESUMO

Due to poor management and the lack of environmental awareness, lots of masks (an emerging form of plastic pollution) are discarded into the environment during the COVID-19, thereby jeopardizing the health of humans and the environment. Our study introduces a novel perspective by examining the impact of physical damage on the microbial composition of masks in the water environment. We focus on the variations in biofilm formation on each layer of both damaged and undamaged masks, which allows us to understand more about the biofilm on each layer and the significant changes that occur when masks are physically damaged. Research has shown that the community structure of microorganisms on discarded masks can be altered in just ten days, showing an evolution from undifferentiated pioneer colonizing species ("non-picky") to adaptive dominant species ("picky"). Especially, considering that discarded masks were inevitably damaged, we found that the biomass on the damaged samples is 1.62-2.38 times higher than that of the undamaged samples, respectively. Moreover, the microbial community structure on it was also significantly different. Genes involved in biogeochemical cycles of nutrients are more enriched in damaged masks. When damaged, the colonization process and community structure in the middle layer significantly differ from those in the inner and outer layers and even enrich more pathogenic bacteria. Based on the above, it is evident that the environmental risk of masks cannot be assessed as a whole, and the middle layer carries a higher risk.

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