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Contractile injection systems (CISs) are cell-puncturing nanodevices that share ancestry with contractile tail bacteriophages. Photorhabdus virulence cassette (PVC) represents one group of extracellular CISs that are present in both bacteria and archaea. Here, we report the cryo-EM structure of an intact PVC from P. asymbiotica. This over 10-MDa device resembles a simplified T4 phage tail, containing a hexagonal baseplate complex with six fibers and a capped 117-nanometer sheath-tube trunk. One distinct feature of the PVC is the presence of three variants for both tube and sheath proteins, indicating a functional specialization of them during evolution. The terminal hexameric cap docks onto the topmost layer of the inner tube and locks the outer sheath in pre-contraction state with six stretching arms. Our results on the PVC provide a framework for understanding the general mechanism of widespread CISs and pave the way for using them as delivery tools in biological or therapeutic applications.
Assuntos
Photorhabdus/química , Photorhabdus/ultraestrutura , Bacteriófago T4/química , Membrana Celular/química , Microscopia Crioeletrônica/métodos , Modelos Moleculares , Photorhabdus/metabolismo , Conformação Proteica , Sistemas de Secreção Tipo VI/metabolismoRESUMO
Carbon structures with covalent bonds connecting C60 molecules have been reported1-3, but their production methods typically result in very small amounts of sample, which restrict the detailed characterization and exploration necessary for potential applications. We report the gram-scale preparation of a new type of carbon, long-range ordered porous carbon (LOPC), from C60 powder catalysed by α-Li3N at ambient pressure. LOPC consists of connected broken C60 cages that maintain long-range periodicity, and has been characterized by X-ray diffraction, Raman spectroscopy, magic-angle spinning solid-state nuclear magnetic resonance spectroscopy, aberration-corrected transmission electron microscopy and neutron scattering. Numerical simulations based on a neural network show that LOPC is a metastable structure produced during the transformation from fullerene-type to graphene-type carbons. At a lower temperature, shorter annealing time or by using less α-Li3N, a well-known polymerized C60 crystal forms owing to the electron transfer from α-Li3N to C60. The carbon K-edge near-edge X-ray absorption fine structure shows a higher degree of delocalization of electrons in LOPC than in C60(s). The electrical conductivity is 1.17 × 10-2 S cm-1 at room temperature, and conduction at T < 30 K appears to result from a combination of metallic-like transport over short distances punctuated by carrier hopping. The preparation of LOPC enables the discovery of other crystalline carbons starting from C60(s).
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In mice and humans, sleep quantity is governed by genetic factors and exhibits age-dependent variation1-3. However, the core molecular pathways and effector mechanisms that regulate sleep duration in mammals remain unclear. Here, we characterize a major signalling pathway for the transcriptional regulation of sleep in mice using adeno-associated virus-mediated somatic genetics analysis4. Chimeric knockout of LKB1 kinase-an activator of AMPK-related protein kinase SIK35-7-in adult mouse brain markedly reduces the amount and delta power-a measure of sleep depth-of non-rapid eye movement sleep (NREMS). Downstream of the LKB1-SIK3 pathway, gain or loss-of-function of the histone deacetylases HDAC4 and HDAC5 in adult brain neurons causes bidirectional changes of NREMS amount and delta power. Moreover, phosphorylation of HDAC4 and HDAC5 is associated with increased sleep need, and HDAC4 specifically regulates NREMS amount in posterior hypothalamus. Genetic and transcriptomic studies reveal that HDAC4 cooperates with CREB in both transcriptional and sleep regulation. These findings introduce the concept of signalling pathways targeting transcription modulators to regulate daily sleep amount and demonstrate the power of somatic genetics in mouse sleep research.
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Transdução de Sinais , Duração do Sono , Transcrição Gênica , Animais , Camundongos , Regulação da Expressão Gênica , Fosforilação , Transdução de Sinais/fisiologia , Sono de Ondas Lentas/genética , Perfilação da Expressão GênicaRESUMO
Neurodevelopmental disorders (NDDs) result from impaired development and functioning of the brain. Here, we identify loss-of-function (LoF) variation in ZFHX3 as a cause for syndromic intellectual disability (ID). ZFHX3 is a zinc-finger homeodomain transcription factor involved in various biological processes, including cell differentiation and tumorigenesis. We describe 42 individuals with protein-truncating variants (PTVs) or (partial) deletions of ZFHX3, exhibiting variable intellectual disability and autism spectrum disorder, recurrent facial features, relative short stature, brachydactyly, and, rarely, cleft palate. ZFHX3 LoF associates with a specific methylation profile in whole blood extracted DNA. Nuclear abundance of ZFHX3 increases during human brain development and neuronal differentiation. ZFHX3 was found to interact with the chromatin remodeling BRG1/Brm-associated factor complex and the cleavage and polyadenylation complex, suggesting a function in chromatin remodeling and mRNA processing. Furthermore, ChIP-seq for ZFHX3 revealed that it predominantly binds promoters of genes involved in nervous system development. We conclude that loss-of-function variants in ZFHX3 are a cause of syndromic ID associating with a specific DNA methylation profile.
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Transtorno do Espectro Autista , Deficiência Intelectual , Transtornos do Neurodesenvolvimento , Humanos , Deficiência Intelectual/genética , Deficiência Intelectual/complicações , Haploinsuficiência/genética , Transtornos do Neurodesenvolvimento/genética , Encéfalo/metabolismo , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismoRESUMO
Polymethoxyflavones (PMFs) are a class of abundant specialized metabolites with remarkable anticancer properties in citrus. Multiple methoxy groups in PMFs are derived from methylation modification catalyzed by a series of hydroxylases and O-methyltransferases (OMTs). However, the specific OMTs that catalyze the systematic O-methylation of hydroxyflavones remain largely unknown. Here, we report that PMFs are highly accumulated in wild mandarins and mandarin-derived accessions, while undetectable in early-diverging citrus species and related species. Our results demonstrated that three homologous genes, CreOMT3, CreOMT4, and CreOMT5, are crucial for PMF biosynthesis in citrus, and their encoded methyltransferases exhibit multisite O-methylation activities for hydroxyflavones, producing seven PMFs in vitro and in vivo. Comparative genomic and syntenic analyses indicated that the tandem CreOMT3, CreOMT4, and CreOMT5 may be duplicated from CreOMT6 and contributes to the genetic basis of PMF biosynthesis in the mandarin group through neofunctionalization. We also demonstrated that N17 in CreOMT4 is an essential amino acid residue for C3-, C5-, C6-, and C3'-O-methylation activity and provided a rationale for the functional deficiency of OMT6 to produce PMFs in early-diverging citrus and some domesticated citrus species. A 1,041-bp deletion in the CreOMT4 promoter, which is found in most modern cultivated mandarins, has reduced the PMF content relative to that in wild and early-admixture mandarins. This study provides a framework for reconstructing PMF biosynthetic pathways, which may facilitate the breeding of citrus fruits with enhanced health benefits.
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Citrus , Citrus/química , Domesticação , Melhoramento Vegetal , Metilação , Metiltransferases/metabolismoRESUMO
Barrett's esophagus is an intestine-like metaplasia and precursor of esophageal adenocarcinoma. Triggered by gastroesophageal reflux disease, the origin of this metaplasia remains unknown. p63-deficient mice, which lack squamous epithelia, may model acid-reflux damage. We show here that p63 null embryos rapidly develop intestine-like metaplasia with gene expression profiles similar to Barrett's metaplasia. We track its source to a unique embryonic epithelium that is normally undermined and replaced by p63-expressing cells. Significantly, we show that a discrete population of these embryonic cells persists in adult mice and humans at the squamocolumnar junction, the source of Barrett's metaplasia. We show that upon programmed damage to the squamous epithelium, these embryonic cells migrate toward adjacent, specialized squamous cells in a process that may recapitulate early Barrett's. Our findings suggest that certain precancerous lesions, such as Barrett's, initiate not from genetic alterations but from competitive interactions between cell lineages driven by opportunity.
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Esôfago de Barrett/patologia , Esôfago/patologia , Animais , Esôfago de Barrett/embriologia , Perfilação da Expressão Gênica , Humanos , Intestino Delgado/citologia , Metaplasia , Camundongos , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Transativadores/genética , Transativadores/metabolismoRESUMO
Neurobiological consequences of traumatic brain injury (TBI) result from a complex interplay of secondary injury responses and sequela that mediates chronic disability. Endothelial cells are important regulators of the cerebrovascular response to TBI. Our work demonstrates that genetic deletion of endothelial cell (EC)-specific EPH receptor A4 (EphA4) using conditional EphA4f/f/Tie2-Cre and EphA4f/f/VE-Cadherin-CreERT2 knockout (KO) mice promotes blood-brain barrier (BBB) integrity and tissue protection, which correlates with improved motor function and cerebral blood flow recovery following controlled cortical impact (CCI) injury. scRNAseq of capillary-derived KO ECs showed increased differential gene expression of BBB-related junctional and actin cytoskeletal regulators, namely, A-kinase anchor protein 12, Akap12, whose presence at Tie2 clustering domains is enhanced in KO microvessels. Transcript and protein analysis of CCI-injured whole cortical tissue or cortical-derived ECs suggests that EphA4 limits the expression of Cldn5, Akt, and Akap12 and promotes Ang2. Blocking Tie2 using sTie2-Fc attenuated protection and reversed Akap12 mRNA and protein levels cortical-derived ECs. Direct stimulation of Tie2 using Vasculotide, angiopoietin-1 memetic peptide, phenocopied the neuroprotection. Finally, we report a noteworthy rise in soluble Ang2 in the sera of individuals with acute TBI, highlighting its promising role as a vascular biomarker for early detection of BBB disruption. These findings describe a contribution of the axon guidance molecule, EphA4, in mediating TBI microvascular dysfunction through negative regulation of Tie2/Akap12 signaling.
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Barreira Hematoencefálica , Lesões Encefálicas Traumáticas , Receptor EphA4 , Animais , Camundongos , Proteínas de Ancoragem à Quinase A/genética , Proteínas de Ancoragem à Quinase A/metabolismo , Barreira Hematoencefálica/metabolismo , Lesões Encefálicas Traumáticas/genética , Lesões Encefálicas Traumáticas/metabolismo , Proteínas de Ciclo Celular/metabolismo , Células Endoteliais/metabolismo , Camundongos Knockout , Receptor TIE-2/genética , Receptor TIE-2/metabolismo , Receptor EphA4/genética , Receptor EphA4/metabolismoRESUMO
In nematodes, spermiogenesis is a process of sperm activation in which nonmotile spermatids are transformed into crawling spermatozoa. Sperm motility acquisition during this process is essential for successful fertilization, but the underlying mechanisms remain to be clarified. Herein, we have found that extracellular adenosine-5'-triphosphate (ATP) level regulation by MIG-23, which is a homolog of human ecto-nucleoside triphosphate diphosphohydrolase (E-NTPDase), was required for major sperm protein (MSP) filament dynamics and sperm motility in the nematode Ascaris suum. During sperm activation, a large amount of ATP was produced in mitochondria and was stored in refringent granules (RGs). Some of the produced ATP was released to the extracellular space through innexin channels. MIG-23 was localized in the sperm plasma membrane and contributed to the ecto-ATPase activity of spermatozoa. Blocking MIG-23 activity resulted in a decrease in the ATP hydrolysis activity of spermatozoa and an increase in the depolymerization rate of MSP filaments in pseudopodia, which eventually affected sperm migration. Overall, our data suggest that MIG-23, which contributes to the ecto-ATPase activity of spermatozoa, regulates sperm migration by modulating extracellular ATP levels.
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Ascaris suum , Trifosfato de Adenosina/metabolismo , Animais , Ascaris suum/metabolismo , Proteínas de Helminto/metabolismo , Humanos , Masculino , Sêmen/metabolismo , Motilidade dos Espermatozoides , Espermatozoides/metabolismoRESUMO
BACKGROUND AND AIMS: HCC is an aggressive cancer with a poor clinical outcome. Understanding the mechanisms that drive tumor initiation is important for improving treatment strategy. This study aimed to identify functional cell membrane proteins that promote HCC tumor initiation. APPROACH AND RESULTS: Tailor-made siRNA library screening was performed for all membrane protein-encoding genes that are upregulated in human HCC (n = 134), with sphere formation as a surrogate readout for tumor initiation. Upon confirmation of membranous localization by immunofluorescence and tumor initiation ability by limiting dilution assay in vivo, LanC-like protein-1 (LANCL1) was selected for further characterization. LANCL1 suppressed intracellular reactive oxygen species (ROS) and promoted tumorigenicity both in vitro and in vivo. Mechanistically, with mass spectrometry, FAM49B was identified as a downstream binding partner of LANCL1. LANCL1 stabilized FAM49B by blocking the interaction of FAM49B with the specific E3 ubiquitin ligase TRIM21, thus protecting FAM49B from ubiquitin-proteasome degradation. The LANCL1-FAM49B axis suppressed the Rac1-NADPH oxidase-driven ROS production, but this suppression of ROS was independent of the glutathione transferase function of LANCL1. Clinically, HCCs with high co-expression of LANCL1 and FAM49B were associated with more advanced tumor stage, poorer overall survival, and disease-free survival. In addition, anti-LANCL1 antibodies targeting the extracellular N-terminal domain were able to suppress the self-renewal ability, as demonstrated by the sphere formation ability of HCC cells. CONCLUSIONS: Our data showed that LANCL1 is a cell surface protein and a key contributor to HCC initiation. Targeting the LANCL1-FAM49B-Rac1-NADPH oxidase-ROS signaling axis may be a promising therapeutic strategy for HCC.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Espécies Reativas de Oxigênio/metabolismo , Proteínas de Membrana/metabolismo , Estresse Oxidativo , NADPH Oxidases/metabolismo , Linhagem Celular Tumoral , Receptores Acoplados a Proteínas G/metabolismoRESUMO
OBJECTIVE: Although accumulating evidence implicating altered gut microbiota in human immunodeficiency virus (HIV) infection and neurodegenerative disorders; however, the association between dysbiosis of the gut microbiota and metabolites in the pathogenesis of HIV-associated neurocognitive disorder (HAND) remains unclear. METHODS: Fecal and plasma samples were obtained from 3 cohorts (HAND, HIV-non-HAND, and healthy controls), metagenomic analysis and metabolomic profiling were performed to investigate alterations in the gut microbial composition and circulating metabolites in HAND. RESULTS: The gut microbiota of people living with HIV (PLWH) had an increased relative abundance of Prevotella and a decreased relative abundance of Bacteroides. In contrast, Prevotella and Megamonas were substantially decreased, and Bacteroides and Phocaeicola were increased in HAND patients. Moreover, untargeted metabolomics identified several neurotransmitters and certain amino acids associated with neuromodulation, and the differential metabolic pathways of amino acids associated with neurocognition were depleted in HAND patients. Notably, most neuromodulatory metabolites are associated with an altered abundance of specific gut bacteria. INTERPRETATION: Our findings provide new insights into the intricate interplay between the gut and microbiome-brain axis in the pathogenesis of HAND, highlighting the potential for developing novel therapeutic strategies that specifically target the gut microbiota. ANN NEUROL 2024;96:306-320.
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Aminoácidos , Microbioma Gastrointestinal , Metabolômica , Metagenômica , Humanos , Microbioma Gastrointestinal/fisiologia , Masculino , Pessoa de Meia-Idade , Feminino , Metabolômica/métodos , Aminoácidos/metabolismo , Aminoácidos/sangue , Adulto , Infecções por HIV/complicações , Complexo AIDS Demência/metabolismo , Complexo AIDS Demência/microbiologia , Fezes/microbiologia , DisbioseRESUMO
Aedes mosquitoes, known as vectors of mosquito-borne diseases, pose significant risks to public health and safety. Modeling the population dynamics of Aedes mosquitoes requires comprehensive approaches due to the complex interplay between biological mechanisms and environmental factors. This study developed a model that couples differential equations with a neural network to simulate the dynamics of mosquito population, and explore the relationships between oviposition rate, temperature, and precipitation. Data from nine cities in Guangdong Province spanning four years were used for model training and parameter estimation, while data from the remaining three cities were reserved for model validation. The trained model successfully simulated the mosquito population dynamics across all twelve cities using the same set of parameters. Correlation coefficients between simulated results and observed data exceeded 0.7 across all cities, with some cities surpassing 0.85, demonstrating high model performance. The coupled neural network in the model effectively revealed the relationships among oviposition rate, temperature, and precipitation, aligning with biological patterns. Furthermore, symbolic regression was used to identify the optimal functional expression for these relationships. By integrating the traditional dynamic model with machine learning, our model can adhere to specific biological mechanisms while extracting patterns from data, thus enhancing its interpretability in biology. Our approach provides both accurate modeling and an avenue for uncovering potential unknown biological mechanisms. Our conclusions can provide valuable insights into designing strategies for controlling mosquito-borne diseases and developing related prediction and early warning systems.
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Aedes , Mosquitos Vetores , Redes Neurais de Computação , Oviposição , Dinâmica Populacional , Aedes/fisiologia , Animais , Mosquitos Vetores/fisiologia , Oviposição/fisiologia , Biologia Computacional , Temperatura , Modelos Biológicos , China , Aprendizado de Máquina , Simulação por Computador , Feminino , Conceitos MeteorológicosRESUMO
Accurate prediction of epidemics is pivotal for making well-informed decisions for the control of infectious diseases, but addressing heterogeneity in the system poses a challenge. In this study, we propose a novel modelling framework integrating the spatio-temporal heterogeneity of susceptible individuals into homogeneous models, by introducing a continuous recruitment process for the susceptibles. A neural network approximates the recruitment rate to develop a Universal Differential Equations (UDE) model. Simultaneously, we pre-set a specific form for the recruitment rate and develop a mechanistic model. Data from a COVID Omicron variant outbreak in Shanghai are used to train the UDE model using deep learning methods and to calibrate the mechanistic model using MCMC methods. Subsequently, we project the attack rate and peak of new infections for the first Omicron wave in China after the adjustment of the dynamic zero-COVID policy. Our projections indicate an attack rate and a peak of new infections of 80.06% and 3.17% of the population, respectively, compared with the homogeneous model's projections of 99.97% and 32.78%, thus providing an 18.6% improvement in the prediction accuracy based on the actual data. Our simulations demonstrate that heterogeneity in the susceptibles decreases herd immunity for ~37.36% of the population and prolongs the outbreak period from ~30 days to ~70 days, also aligning with the real case. We consider that this study lays the groundwork for the development of a new class of models and new insights for modelling heterogeneity.
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COVID-19 , Biologia Computacional , Aprendizado Profundo , SARS-CoV-2 , Humanos , COVID-19/epidemiologia , COVID-19/virologia , China/epidemiologia , Biologia Computacional/métodos , Redes Neurais de Computação , Suscetibilidade a Doenças/epidemiologia , Análise Espaço-Temporal , Modelos EpidemiológicosRESUMO
Bladder cancer(BC) is one of the most prevalent cancers in the urinary tract, with high recurrence and fatality rates. Research indicates that go-ichi-ni-san complex subunit 1 (GINS1) crucially influences cancer progression by regulating DNA replication through cell cycle modulation. Thus, suppressing the active proliferation of cells in tumor tissues may require silencing GINS1. However, the consequences of GINS1 in bladder cancer aren't to be determined. In this paper, we examine the role and mechanism of GINS1 in the development of bladder cancer. GINS1 expression levels and prognostic relevance in bladder cancer were validated using Western blotting, immunohistochemistry, and Kaplan-Meier survival analysis. The influence of GINS1 on bladder cancer was investigated using a variety of approaches, including cell transfection, cell counts, transwell migrations, colony formation, and flow cytometry. Immunohistochemistry studies demonstrate that GINS1 expression is increased in bladder cancer tissues. GINS1 silencing resulted in an arrest of the cell cycle at the phase of G0/G1, which inhibited BC cell growth both in vitro and in vivo. GINS1 knockdown also hindered the AKT/mTOR pathway. Furthermore, increased GINS1 expression affects the cell cycle and stimulates the AKT/mTOR pathway, allowing BC to develop more quickly. Consequently, GINS1 occurs as a latent therapeutic target, particularly for individuals with BC.
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Proliferação de Células , Proteínas Cromossômicas não Histona , Proteínas Proto-Oncogênicas c-akt , Transdução de Sinais , Serina-Treonina Quinases TOR , Neoplasias da Bexiga Urinária , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/metabolismo , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Serina-Treonina Quinases TOR/metabolismo , Serina-Treonina Quinases TOR/genética , Proteínas Cromossômicas não Histona/metabolismo , Proteínas Cromossômicas não Histona/genética , Proliferação de Células/genética , Animais , Linhagem Celular Tumoral , Proteínas Proto-Oncogênicas c-myc/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Regulação Neoplásica da Expressão Gênica , Camundongos , Progressão da Doença , Camundongos Nus , Masculino , Feminino , Prognóstico , Camundongos Endogâmicos BALB C , Proteínas de Ligação a DNARESUMO
None of the existing approaches for regulating gene expression can bidirectionally and quantitatively fine-tune gene expression to desired levels. Here, on the basis of precise manipulations of the Kozak sequence, which has a remarkable influence on translation initiation, we proposed and validated a novel strategy to directly modify the upstream nucleotides of the translation initiation codon of a given gene to flexibly alter the gene translation level by using base editors and prime editors. When the three nucleotides upstream of the translation initiation codon (named KZ3, part of the Kozak sequence), which exhibits the most significant base preference of the Kozak sequence, were selected as the editing region to alter the translation levels of proteins, we confirmed that each of the 64 KZ3 variants had a different translation efficiency, but all had similar transcription levels. Using the ranked KZ3 variants with different translation efficiencies as predictors, base editor- and prime editor-mediated mutations of KZ3 in the local genome could bidirectionally and quantitatively fine-tune gene translation to the anticipated levels without affecting transcription in vitro and in vivo. Notably, this strategy can be extended to the whole Kozak sequence and applied to all protein-coding genes in all eukaryotes.
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Edição de Genes , Iniciação Traducional da Cadeia Peptídica , Códon/genética , Códon de Iniciação/genética , Nucleotídeos/metabolismo , Biossíntese de Proteínas , RNA Mensageiro/metabolismo , Células EucarióticasRESUMO
Early stage hepatocellular carcinoma (HCC) presents a formidable challenge in clinical settings due to its asymptomatic progression and the limitations of current imaging techniques in detecting micro-HCC lesions. Addressing this critical issue, we introduce a novel ultrathin gadolinium-oxide (Gd-oxide) nanosheet-based platform with heightened sensitivity for high-field MRI and as a therapeutic agent for HCC. Synthesized via a digestive ripening process, these Gd-oxide nanosheets exhibit an exceptional acid-responsive profile. The integration of the ultrathin Gd-oxide with an acid-responsive polymer creates an ultrasensitive high-field MRI probe, enabling the visualization of submillimeter-sized tumors with superior sensitivity. Our research underscores the ultrasensitive probe's efficacy in the treatment of orthotopic HCC. Notably, the ultrasensitive probe functions dually as a companion diagnostic tool, facilitating simultaneous imaging and therapy with real-time treatment monitoring capabilities. In conclusion, this study showcases an innovative companion diagnostic tool that holds promise for the early detection and effective treatment of micro-HCC.
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Carcinoma Hepatocelular , Meios de Contraste , Gadolínio , Neoplasias Hepáticas , Imageamento por Ressonância Magnética , Imageamento por Ressonância Magnética/métodos , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/diagnóstico , Neoplasias Hepáticas/diagnóstico por imagem , Humanos , Gadolínio/química , Meios de Contraste/química , Animais , Camundongos , Nanoestruturas/química , Nanoestruturas/uso terapêutico , Linhagem Celular TumoralRESUMO
Metal phosphide anode materials encounter poor reversibility of the discharge product (metal and Na3P) and large volume variation, resulting in low initial Coulombic efficiency (ICE) and severe capacity degradation. Herein, a bimetallic phosphide (CoMoP) with three-dimensional ordered porous (3DOP) nanoconstruction was fabricated, which presents a reduced Gibbs free energy change (ΔG) of redox reaction between Co-Mo/Na3P and CoMoP and improved conductivity compared to CoP and MoP. Additionally, the 3DOP architecture could disperse stress and reduce strain during cycling, thus improving structural stability of CoMoP. In situ and ex situ characterizations and electrochemical measurements suggest that 3DOP CoMoP exhibits highly reversible sodium storage with an ICE of 58% at 0.1 A g-1, enhanced reaction dynamics, and good cycling stability with around 0.04% capacity decay per cycle at 1 A g-1 after 1000 cycles. Consequently, this work offers a new perspective to solve issues of reversibility of redox chemistry and volume expansion for secondary batteries.
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OBJECTIVE: Fat mass and obesity-associated protein (FTO), an eraser of N 6-methyadenosine (m6A), plays oncogenic roles in various cancers. However, its role in hepatocellular carcinoma (HCC) is unclear. Furthermore, small extracellular vesicles (sEVs, or exosomes) are critical mediators of tumourigenesis and metastasis, but the relationship between FTO-mediated m6A modification and sEVs in HCC is unknown. DESIGN: The functions and mechanisms of FTO and glycoprotein non-metastatic melanoma protein B (GPNMB) in HCC progression were investigated in vitro and in vivo. Neutralising antibody of syndecan-4 (SDC4) was used to assess the significance of sEV-GPNMB. FTO inhibitor CS2 was used to examine the effects on anti-PD-1 and sorafenib treatment. RESULTS: FTO expression was upregulated in patient HCC tumours. Functionally, FTO promoted HCC cell proliferation, migration and invasion in vitro, and tumour growth and metastasis in vivo. FTO knockdown enhanced the activation and recruitment of tumour-infiltrating CD8+ T cells. Furthermore, we identified GPNMB to be a downstream target of FTO, which reduced the m6A abundance of GPNMB, hence, stabilising it from degradation by YTH N 6-methyladenosine RNA binding protein F2. Of note, GPNMB was packaged into sEVs derived from HCC cells and bound to the surface receptor SDC4 of CD8+ T cells, resulting in the inhibition of CD8+ T cell activation. A potential FTO inhibitor, CS2, suppresses the oncogenic functions of HCC cells and enhances the sensitivity of anti-PD-1 and sorafenib treatment. CONCLUSION: Targeting the FTO/m6A/GPNMB axis could significantly suppress tumour growth and metastasis, and enhance immune activation, highlighting the potential of targeting FTO signalling with effective inhibitors for HCC therapy.
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BACKGROUND: Protein residue-residue distance maps are used for remote homology detection, protein information estimation, and protein structure research. However, existing prediction approaches are time-consuming, and hundreds of millions of proteins are discovered each year, necessitating the development of a rapid and reliable prediction method for protein residue-residue distances. Moreover, because many proteins lack known homologous sequences, a waiting-free and alignment-free deep learning method is needed. RESULT: In this study, we propose a learning framework named FreeProtMap. In terms of protein representation processing, the proposed group pooling in FreeProtMap effectively mitigates issues arising from high-dimensional sparseness in protein representation. In terms of model structure, we have made several careful designs. Firstly, it is designed based on the locality of protein structures and triangular inequality distance constraints to improve prediction accuracy. Secondly, inference speed is improved by using additive attention and lightweight design. Besides, the generalization ability is improved by using bottlenecks and a neural network block named local microformer. As a result, FreeProtMap can predict protein residue-residue distances in tens of milliseconds and has higher precision than the best structure prediction method. CONCLUSION: Several groups of comparative experiments and ablation experiments verify the effectiveness of the designs. The results demonstrate that FreeProtMap significantly outperforms other state-of-the-art methods in accurate protein residue-residue distance prediction, which is beneficial for lots of protein research works. It is worth mentioning that we could scan all proteins discovered each year based on FreeProtMap to find structurally similar proteins in a short time because the fact that the structure similarity calculation method based on distance maps is much less time-consuming than algorithms based on 3D structures.
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Proteínas , Proteínas/química , Biologia Computacional/métodos , Bases de Dados de Proteínas , Conformação Proteica , Algoritmos , Análise de Sequência de Proteína/métodos , Redes Neurais de ComputaçãoRESUMO
Atomic force microscope enables ultra-precision imaging of living cells. However, atomic force microscope imaging is a complex and time-consuming process. The obtained images of living cells usually have low resolution and are easily influenced by noise leading to unsatisfactory imaging quality, obstructing the research and analysis based on cell images. Herein, an adaptive attention image reconstruction network based on residual encoder-decoder was proposed, through the combination of deep learning technology and atomic force microscope imaging supporting high-quality cell image acquisition. Compared with other learning-based methods, the proposed network showed higher peak signal-to-noise ratio, higher structural similarity and better image reconstruction performances. In addition, the cell images reconstructed by each method were used for cell recognition, and the cell images reconstructed by the proposed network had the highest cell recognition rate. The proposed network has brought insights into the atomic force microscope-based imaging of living cells and cell image reconstruction, which is of great significance in biological and medical research.
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Processamento de Imagem Assistida por Computador , Microscopia de Força Atômica , Microscopia de Força Atômica/métodos , Processamento de Imagem Assistida por Computador/métodos , Humanos , Razão Sinal-Ruído , Aprendizado ProfundoRESUMO
Pancreatic ductal adenocarcinoma (PDAC), a highly lethal malignancy, exhibits escalating incidence and mortality rates, underscoring the urgent need for the identification of novel therapeutic targets and strategies. The BAG3 protein, a multifunctional regulator involved in various cellular processes, notably plays a crucial role in promoting tumor progression and acts as a potential "bridge" between tumors and the tumor microenvironment. In this study, we demonstrate that PDAC cells secrete BAG3 (sBAG3), which engages the IFITM2 receptor to activate the MAPK signaling pathway, specifically enhancing pERK activity, thereby propelling PDAC growth. Furthermore, our preliminary investigation into the effects of sBAG3 on co-cultured NK cells intriguingly discovered that sBAG3 diminishes NK cell cytotoxicity and active molecule expression. In conclusion, our findings confirm the pivotal role of the sBAG3-IFITM2 axis in fostering PDAC progression, highlighting the potential significance of sBAG3 as a dual therapeutic target for both tumor and immune cells.