RESUMO
Histone acetylation plays critical roles in chromatin remodeling, DNA repair, and epigenetic regulation of gene expression, but the underlying mechanisms are unclear. Proteasomes usually catalyze ATP- and polyubiquitin-dependent proteolysis. Here, we show that the proteasomes containing the activator PA200 catalyze the polyubiquitin-independent degradation of histones. Most proteasomes in mammalian testes ("spermatoproteasomes") contain a spermatid/sperm-specific α subunit α4 s/PSMA8 and/or the catalytic ß subunits of immunoproteasomes in addition to PA200. Deletion of PA200 in mice abolishes acetylation-dependent degradation of somatic core histones during DNA double-strand breaks and delays core histone disappearance in elongated spermatids. Purified PA200 greatly promotes ATP-independent proteasomal degradation of the acetylated core histones, but not polyubiquitinated proteins. Furthermore, acetylation on histones is required for their binding to the bromodomain-like regions in PA200 and its yeast ortholog, Blm10. Thus, PA200/Blm10 specifically targets the core histones for acetylation-mediated degradation by proteasomes, providing mechanisms by which acetylation regulates histone degradation, DNA repair, and spermatogenesis.
Assuntos
Reparo do DNA , Histonas/metabolismo , Proteínas Nucleares/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Espermatogênese , Testículo/metabolismo , Acetilação , Sequência de Aminoácidos , Animais , Quebras de DNA de Cadeia Dupla , Humanos , Masculino , Camundongos , Dados de Sequência Molecular , Proteínas Nucleares/química , Estrutura Terciária de Proteína , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Alinhamento de SequênciaRESUMO
The COVID-19 pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has posed a worldwide threat in the past 3 years. Although it has been widely and intensively investigated, the mechanism underlying the coronavirus-host interaction requires further elucidation, which may contribute to the development of new antiviral strategies. Here, we demonstrated that the host cAMP-responsive element-binding protein (CREB1) interacts with the non-structural protein 13 (nsp13) of SARS-CoV-2, a conserved helicase for coronavirus replication, both in cells and in lung tissues subjected to SARS-CoV-2 infection. The ATPase and helicase activity of viral nsp13 were shown to be potentiated by CREB1 association, as well as by Protein kinase A (PKA)-mediated CREB1 activation. SARS-CoV-2 replication is significantly suppressed by PKA Cα, cAMP-activated protein kinase catalytic subunit alpha (PRKACA), and CREB1 knockdown or inhibition. Consistently, the CREB1 inhibitor 666-15 has shown significant antiviral effects against both the WIV04 strain and the Omicron strain of the SARS-CoV-2. Our findings indicate that the PKA-CREB1 signaling axis may serve as a novel therapeutic target against coronavirus infection. IMPORTANCE: In this study, we provide solid evidence that host transcription factor cAMP-responsive element-binding protein (CREB1) interacts directly with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) helicase non-structural protein 13 (nsp13) and potentiate its ATPase and helicase activity. And by live SARS-CoV-2 virus infection, the inhibition of CREB1 dramatically impairs SARS-CoV-2 replication in vivo. Notably, the IC50 of CREB1 inhibitor 666-15 is comparable to that of remdesivir. These results may extend to all highly pathogenic coronaviruses due to the conserved nsp13 sequences in the virus.
Assuntos
RNA-Polimerase RNA-Dependente de Coronavírus , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico , Proteínas Quinases Dependentes de AMP Cíclico , Interações entre Hospedeiro e Microrganismos , SARS-CoV-2 , Proteínas não Estruturais Virais , Replicação Viral , Humanos , Adenosina Trifosfatases/metabolismo , Antivirais/farmacologia , RNA-Polimerase RNA-Dependente de Coronavírus/metabolismo , COVID-19/virologia , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/antagonistas & inibidores , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/deficiência , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Subunidades Catalíticas da Proteína Quinase Dependente de AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , DNA Helicases/metabolismo , Concentração Inibidora 50 , RNA Helicases/metabolismo , SARS-CoV-2/classificação , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/enzimologia , SARS-CoV-2/crescimento & desenvolvimento , Transdução de Sinais/efeitos dos fármacos , Proteínas não Estruturais Virais/metabolismo , Replicação Viral/efeitos dos fármacos , Feminino , Animais , CamundongosRESUMO
Anoikis plays a crucial role in the progression, prognosis, and immune response of lung adenocarcinoma (LUAD). However, its specific impact on LUAD remains unclear. In this study, we investigated the intricate interplay of nesting apoptotic factors in LUAD. By analyzing nine key nesting apoptotic factors, we categorized LUAD patients into two distinct clusters. Further examination of immune cell profiles revealed that Cluster A exhibited greater infiltration of innate immune cells than did Cluster B. Additionally, we identified two genes closely associated with prognosis and developed a predictive model to differentiate patients based on molecular clusters. Our findings suggest that the loss of specific anoikis-related genes could significantly influence the prognosis, tumor microenvironment, and clinical features of LUAD patients. Furthermore, we validated the expression and functional roles of two pivotal prognostic genes, solute carrier family 2 member 1 (SLC2A1) and sphingosine kinase 1 (SPHK1), in regulating tumor cell viability, migration, apoptosis, and anoikis. These results offer valuable insights for future mechanistic investigations. In conclusion, this study provides new avenues for advancing our understanding of LUAD, improving prognostic assessments, and developing more effective immunotherapy strategies.
Assuntos
Adenocarcinoma de Pulmão , Anoikis , Neoplasias Pulmonares , Humanos , Anoikis/genética , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/imunologia , Adenocarcinoma de Pulmão/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/patologia , Prognóstico , Microambiente Tumoral/imunologia , Microambiente Tumoral/genética , Regulação Neoplásica da Expressão Gênica , Feminino , Masculino , Pessoa de Meia-Idade , Linhagem Celular Tumoral , Apoptose/genéticaRESUMO
Highly potent heterocyclic drugs are frequently poorly water soluble, leading to limited or abandoned further drug development. Nanoparticle technology offers a powerful delivery approach by enhancing the solubility and bioavailability of hydrophobic therapeutics. However, the common usage of organic solvents causes unwanted toxicity and process complexity, therefore limiting the scale-up of nanomedicine technology for clinical translation. Here, we show that an organic-solvent-free methodology for hydrophobic drug encapsulation can be obtained using polymers based on glucose and tyrosine. An aqueous solution based on a tyrosine-containing glycopolymer is able to dissolve solid dasatinib directly without adding an organic solvent, resulting in the formation of very small nanoparticles of around 10 nm loaded with up to 16 wt % of drug. This polymer is observed to function as both a drug solubilizer and a nanocarrier at the same time, offering a simple route for the delivery of insoluble drugs.
Assuntos
Nanopartículas , Tirosina , Preparações Farmacêuticas/química , Glucose , Água/química , Solventes/química , Polímeros/química , Nanopartículas/química , SolubilidadeRESUMO
Fresh sweat contains a diverse range of physiological indicators that can effectively reflect changes in the body. However, existing wearable sweat detection systems face challenges in efficiently collecting and detecting fresh sweat in real-time. Additionally, they often lack the necessary deformation capabilities, resulting in discomfort for the wearer. Here, a fully elastic wearable electrochemical sweat detection system is developed that integrates a sweat-collecting microfluidic chip, a multi-parameter electrochemical sensor, a micro-heater, and a sweat detection elastic circuit board system. The unique tree-bionic structure of the microfluidic chip significantly enhances the efficiency of fresh sweat collection and discharge, enabling real-time detection by the electrochemical sensors. The sweat multi-parameter electrochemical sensor offers high-precision and high-sensitivity measurements of sodium ions, potassium ions, lactate, and glucose. The electronic system is built on an elastic circuit board that matches perfectly to wrinkled skin, ensuring improved wearing comfort and enabling multi-channel data sampling, processing, and wireless transmission. This state-of-the-art system represents a significant advancement in the field of elastic wearable sweat detection and holds promising potential for extending its capabilities to the detection of other sweat markers or various wearable applications.
Assuntos
Técnicas Biossensoriais , Dispositivos Eletrônicos Vestíveis , Suor/química , Microfluídica , Árvores , Biônica , Íons/análise , Técnicas Biossensoriais/métodosRESUMO
Pancreatic ductal adenocarcinoma (PDAC) is a highly invasive cancer with a poor prognosis and a 5-year survival rate of less than 11%. As a member of the CAP superfamily of proteins, the role of peptidase inhibitor 16 (Pi16) in tumor progression is still unclear. Immunohistochemistry and quantitative RT-PCR methods were used to detect the expression levels of Pi16 protein and mRNA in PDAC patients. CRISPR/Cas9 technology was used to knock out the expression of Pi16 in PDAC cell lines. In vivo and in vitro experiments were used to verify the effect of Pi16 on PDAC proliferation ability. By RNA sequencing, we found that oligoadenylate synthetase L (OASL) can serve as a potential downstream target of Pi16. The expression of Pi16 was higher in PDAC tissues than in matched adjacent tissues. High expression of Pi16 was associated with PDAC progression and poor prognosis. Overexpression of Pi16 could promote the proliferation of PDAC cells in vitro and in vivo. Bioinformatics analysis and coimmunoprecipitation assays showed that Pi16 could bind to OASL. Moreover, the functional recovery test confirmed that Pi16 could promote the proliferation of PDAC via OASL. Our present study demonstrates that Pi16 might participate in the occurrence and development of PDAC by regulating cell proliferation by binding to OASL, indicating that Pi16 might be a promising novel therapeutic target for PDAC.
Assuntos
2',5'-Oligoadenilato Sintetase , Nucleotídeos de Adenina , Carcinoma Ductal Pancreático , Glicoproteínas , Neoplasias Pancreáticas , Humanos , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Glicoproteínas/metabolismo , Proteínas de Transporte/metabolismo , 2',5'-Oligoadenilato Sintetase/metabolismoRESUMO
The field of single-chain nanoparticles (SCNPs) continues to mature, and an increasing range of reports have emerged that explore the application of these small nanoparticles. A key application for SCNPs is in the field of drug delivery, and recent work suggests that SCNPs can be readily internalized by cells. However, limited attention has been directed to the delivery of small-molecule drugs using SCNPs. Moreover, studies on the physicochemical effects of drug loading on SCNP performance is so far missing, despite the accepted view that such small nanoparticles should be significantly affected by the drug loading content. To address this gap, we prepared a library of SCNPs bearing different amounts of a covalently conjugated therapeutic drug-sulfasalazine (SSZ). We evaluated the impact of the conjugated drug loading on both the synthesis and biological activity of SCNPs on pancreatic cancer cells (AsPC-1). Our results reveal that covalent drug conjugation to the side chains of the SCNP polymer precursor interferes with chain collapse and cross-linking, which demands optimization of reaction conditions to reach high degrees of cross-linking efficiencies. Small-angle neutron scattering and diffusion-ordered spectroscopy nuclear magnetic resonance (DOSY NMR) analyses reveal that SCNPs with a higher drug loading display larger sizes and looser structures, as well as increased hydrophobicity associated with a higher SSZ content. Increased SSZ loading led to reduced cellular uptake when assessed in vitro, whereby SCNP aggregation on the surface of AsPC-1 cells led to reduced toxicity. This work highlights the effects of drug loading on the drug delivery efficiency and biological behavior of SCNPs.
Assuntos
Nanopartículas , Nanopartículas/química , Sistemas de Liberação de Medicamentos/métodos , Polímeros/química , Preparações FarmacêuticasRESUMO
The high recurrence rate of renal uric acid stone (UAS) poses a significant challenge for urologists, and potassium sodium hydrogen citrate (PSHC) has been proven to be an effective oral dissolution drug. However, no studies have investigated the impact of PSHC on gut microbiota and its metabolites during stone dissolution therapy. We prospectively recruited 37 UAS patients and 40 healthy subjects, of which 12 patients completed a 3-month pharmacological intervention. Fasting vein blood was extracted and mid-stream urine was retained for biochemical testing. Fecal samples were collected for 16S ribosomal RNA (rRNA) gene sequencing and short chain fatty acids (SCFAs) content determination. UAS patients exhibited comorbidities such as obesity, hypertension, gout, and dyslipidemia. The richness and diversity of the gut microbiota were significantly decreased in UAS patients, Bacteroides and Fusobacterium were dominant genera while Subdoligranulum and Bifidobacterium were poorly enriched. After PSHC intervention, there was a significant reduction in stone size accompanied by decreased serum uric acid and increased urinary pH levels. The abundance of pathogenic bacterium Fusobacterium was significantly downregulated following the intervention, whereas there was an upregulation observed in SCFA-producing bacteria Lachnoclostridium and Parasutterella, leading to a significant elevation in butyric acid content. Functions related to fatty acid synthesis and amino acid metabolism within the microbiota showed upregulation following PSHC intervention. The correlation analysis revealed a positive association between stone pathogenic bacteria abundance and clinical factors for stone formation, while a negative correlation with SCFAs contents. Our preliminary study revealed that alterations in gut microbiota and metabolites were the crucial physiological adaptation to PSHC intervention. Targeted regulation of microbiota and SCFA holds promise for enhancing drug therapy efficacy and preventing stone recurrence. KEY POINTS: ⢠Bacteroides and Fusobacterium were identified as dominant genera for UAS patients ⢠After PSHC intervention, Fusobacterium decreased and butyric acid content increased ⢠The microbiota increased capacity for fatty acid synthesis after PSHC intervention.
Assuntos
Ácido Cítrico , Microbioma Gastrointestinal , Humanos , Citrato de Potássio , Citrato de Sódio , Potássio , Ácido Úrico , Sódio , Citratos , Bacteroides , Ácido ButíricoRESUMO
Cytoskeletal microtubules (MTs) are nucleated from γ-tubulin ring complexes (γTuRCs) located at MT organizing centers (MTOCs), such as the centrosome. However, the exact regulatory mechanism of γTuRC assembly is not fully understood. Here, we showed that the nonreceptor tyrosine kinase c-Abl was associated with and phosphorylated γ-tubulin, the essential component of the γTuRC, mainly on the Y443 residue by in vivo (immunofluorescence and immunoprecipitation) or in vitro (surface plasmon resonance) detection. We further demonstrated that phosphorylation deficiency significantly impaired γTuRC assembly, centrosome construction, and MT nucleation. c-Abl/Arg deletion and γ-tubulin Y443F mutation resulted in an abnormal morphology and compromised spindle function during mitosis, eventually causing uneven chromosome segregation. Our findings reveal that γTuRC assembly and nucleation function are regulated by Abl kinase-mediated γ-tubulin phosphorylation, revealing a fundamental mechanism that contributes to the maintenance of MT function.
Assuntos
Centro Organizador dos Microtúbulos , Microtúbulos , Proteínas Proto-Oncogênicas c-abl , Tubulina (Proteína) , Centrossomo/metabolismo , Centro Organizador dos Microtúbulos/metabolismo , Microtúbulos/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-abl/genética , Proteínas Proto-Oncogênicas c-abl/metabolismo , Tubulina (Proteína)/genética , Tubulina (Proteína)/metabolismoRESUMO
Necroptosis-mediated cell death is an important mechanism in intracerebral hemorrhage (ICH)-induced secondary brain injury (SBI). Our previous study has demonstrated that receptor-interacting protein 1 (RIP1) mediated necroptosis in SBI after ICH. However, further mechanisms, such as the roles of receptor-interacting protein 3 (RIP3), mixed lineage kinase domain-like protein (MLKL), and Ca2+ /calmodulin-dependent protein kinase II (CaMK II), remain unclear. We hypothesized that RIP3, MLKL, and CaMK II might participate in necroptosis after ICH, including their phosphorylation. The ICH model was induced by autologous blood injection. First, we found the activation of necroptosis after ICH in brain tissues surrounding the hematoma (propidium iodide staining). Meanwhile, the phosphorylation and expression of RIP3, MLKL, and CaMK II were differently up-regulated (western blotting and immunofluorescent staining). The specific inhibitors could suppress RIP3, MLKL, and CaMK II (GSK'872 for RIP3, necrosulfonamide for MLKL, and KN-93 for CaMK II). We found the necroptosis surrounding the hematoma and the concrete interactions in RIP3-MLKL/RIP3-CaMK II also both decreased after the specific intervention (co-immunoprecipitation). Then we conducted the short-/long-term neurobehavioral tests, and the rats with specific inhibition mostly had better performance. We also found less blood-brain barrier (BBB) injury, and less neuron loss (Nissl staining) in intervention groups, which supported the neurobehavioral tests. Besides, oxidative stress and inflammation were also alleviated with intervention, which had significant less reactive oxygen species (ROS), tumor necrosis factor (TNF)-α, lactate dehydrogenase (LDH), Iba1, and GFAP surrounding the hematoma. These results confirmed that RIP3-phosphorylated MLKL and CaMK II participate in ICH-induced necroptosis and could provide potential targets for the treatment of ICH patients.
Assuntos
Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina , Necroptose , Proteínas Quinases , Proteína Serina-Treonina Quinases de Interação com Receptores , Animais , Ratos , Apoptose , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Hemorragia Cerebral , Hematoma , Necrose , Neurônios , Fator de Necrose Tumoral alfa , Proteínas Quinases/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismoRESUMO
We found an elevation of circulating TFH13 cell subset in asthmatic children and the frequency of TFH13 cells positively correlated with the plasma dust mite-specific IgE levels. These results indicated that TFH13 cell subset may be responsible for the immunopathogenesis of excessive IgE accumulation in children with allergic asthma.
Assuntos
Linfócitos T Auxiliares-Indutores , Humanos , CriançaRESUMO
SARS-CoV-2 is the causative agent of the ongoing pandemic of coronavirus disease 2019 (COVID-19) and poses a significant threat to global health. N protein (NP), which is a major pathogenic protein among betacoronaviruses, binds to the viral RNA genome to allow viral genome packaging and viral particle release. Recent studies showed that NP antagonizes interferon (IFN) induction and mediates phase separation. Using live SARS-CoV-2 viruses, this study provides solid evidence showing that SARS-CoV-2 NP associates with G3BP1 and G3BP2 in vitro and in vivo. NPSARS-CoV-2 could efficiently suppress G3BP-mediated SG formation and potentiate viral infection by overcoming G3BP1-mediated antiviral innate immunity. G3BP1 conditional knockout mice (g3bp1fl/fL, Sftpc-Cre) exhibit significantly higher lung viral loads after SARS-CoV-2 infection than wild-type mice. Our findings contribute to the growing body of knowledge regarding the pathogenicity of NPSARS-CoV-2 and provide insight into new therapeutics targeting NPSARS-CoV-2. IMPORTANCE In this study, by in vitro assay and live SARS-CoV-2 virus infection, we provide solid evidence that the SARS-CoV-2 NP associates with G3BP1 and G3BP2 in vitro and in vivo. NPSARS-CoV-2 could efficiently suppress G3BP-mediated SG formation and potentiate viral infection by overcoming antiviral innate immunity mediated by G3BP1 in A549 cell lines and G3BP1 conditional knockout mice (g3bp1-cKO) mice, which provide in-depth evidence showing the mechanism underlying NP-related SARS-CoV-2 pathogenesis through G3BPs.
Assuntos
COVID-19 , Proteínas do Nucleocapsídeo de Coronavírus , Proteínas de Ligação a Poli-ADP-Ribose , SARS-CoV-2 , Replicação Viral , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , COVID-19/imunologia , COVID-19/virologia , Proteínas do Nucleocapsídeo de Coronavírus/metabolismo , DNA Helicases/metabolismo , Interações entre Hospedeiro e Microrganismos/imunologia , Camundongos , Fosfoproteínas/metabolismo , Proteínas de Ligação a Poli-ADP-Ribose/metabolismo , RNA Helicases/metabolismo , Proteínas com Motivo de Reconhecimento de RNA/metabolismo , Proteínas de Ligação a RNA/metabolismo , Grânulos de Estresse , Replicação Viral/genéticaRESUMO
While the effects of nanoparticle properties such as shape and size on cellular uptake are widely studied, influences exerted by drug loading have so far been ignored. In this work, nanocellulose (NC) coated by Passerini reaction with poly(2-hydroxy ethyl acrylate) (PHEA-g-NC) was loaded with various amounts of ellipticine (EPT) by electrostatic interactions. The drug-loading content was determined by UV-vis spectroscopy to range between 1.68 and 8.07 wt %. Dynamic light scattering and small-angle neutron scattering revealed an increased dehydration of the polymer shell with increasing drug-loading content, which led to higher protein adsorption and more aggregation. The nanoparticle with the highest drug-loading content, NC-EPT8.0, displayed reduced cellular uptake in U87MG glioma cells and MRC-5 fibroblasts. This also translated into reduced toxicity in these cell lines as well as the breast cancer MCF-7 and the macrophage RAW264.7 cell lines. Additionally, the toxicity in U87MG cancer spheroids was unfavorable. The nanoparticle with the best performance was found to have intermediate drug-loading content where the cellular uptake was adequately high while each nanoparticle was able to deliver a sufficiently toxic amount into the cells. Medium drug loading did not hinder uptake into cells while maintaining sufficiently toxic drug concentrations. It was concluded that while striving for a high drug-loading content is appropriate when designing clinically relevant nanoparticles, it needs to be considered that the drug can cause changes in the physicochemical properties of the nanoparticles that might cause unfavorable effects.
Assuntos
Neoplasias da Mama , Nanopartículas , Humanos , Feminino , Polímeros/química , Portadores de Fármacos/química , Linhagem Celular , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Macrófagos , Nanopartículas/químicaRESUMO
Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) drives apoptosis selectively in cancer cells by clustering death receptors (DR4 and DR5). While it has excellent in vitro selectivity and toxicity, the TRAIL protein has a very low circulation half-life in vivo, which has hampered clinical development. Here, we developed core-cross-linked micelles that present multiple copies of a TRAIL-mimicking peptide at its surface. These micelles successfully induce apoptosis in a colon cancer cell line (COLO205) via DR4/5 clustering. Micelles with a peptide density of 15% (roughly 1 peptide/45 nm2) displayed the strongest activity with an IC50 value of 0.8 µM (relative to peptide), demonstrating that the precise spatial arrangement of ligands imparted by a protein such as a TRAIL may not be necessary for DR4/5/signaling and that a statistical network of monomeric ligands may suffice. As micelles have long circulation half-lives, we propose that this could provide a potential alternative drug to TRAIL and stimulate the use of micelles in other membrane receptor clustering networks.
Assuntos
Proteínas Reguladoras de Apoptose , Neoplasias do Colo , Humanos , Proteínas Reguladoras de Apoptose/metabolismo , Proteínas Reguladoras de Apoptose/farmacologia , Ligante Indutor de Apoptose Relacionado a TNF/farmacologia , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Micelas , Ligantes , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Linhagem Celular Tumoral , Apoptose , Fator de Necrose Tumoral alfa/metabolismo , Neoplasias do Colo/tratamento farmacológico , Peptídeos/farmacologia , Peptídeos/metabolismo , Proteínas de TransporteRESUMO
Strain KLBMP 9083T, a novel actinobacterium, was isolated from weathered soils collected from a karst area in Anshun, Guizhou Province, PR China. The taxonomic position of strain KLBMP 9083T was studied using the polyphasic approach. Phylogenetic analysis based on the 16S rRNA gene sequence indicated that strain KLBMP 9083T formed a stabilized monophyletic clade with its closest relative strain Antribacter gilvus CGMCC 1.13856T (98.4â% 16S rRNA gene sequence similarity). The peptidoglycan hydrolysates contained alanine, glutamic acid, threonine and lysine. The polar lipids were composed of diphosphatidylglycerol, phosphatidylinositol, phosphatidylinositol mannoside, an unidentified phosphoglycolipid, an unidentified phospholipid and an unidentified glycolipid. The predominant menaquinones were MK-9(H8) (87.1â%), MK-9(H6) (7.3â%) and MK-9(H4) (5.6â%). The major fatty acids (>10â%) were anteiso-C15â:â0 and iso-C15â:â0. The genomic DNA G+C content was 72.3 mol%. The digital DNA-DNA hybridization and average nucleotide identity values between strain KLBMP 9083T and A. gilvus CGMCC 1.13856T were 23.4 and 79.9â%, respectively. On the basis of morphological, chemotaxonomic and phylogenetic characteristics, strain KLBMP 9083T represents a novel species of the genus Antribacter, for which the name Antribacter soli sp. nov. is proposed. The type strain is KLBMP 9083T (=CGMCC 4.7737T=NBRC 115577T).
Assuntos
Actinobacteria , Actinomycetales , Ácidos Graxos/química , Solo , Filogenia , RNA Ribossômico 16S/genética , DNA Bacteriano/genética , Composição de Bases , Técnicas de Tipagem Bacteriana , Análise de Sequência de DNA , Fosfolipídeos , Vitamina K 2RESUMO
An efficient radical cascade cyclization of unactivated alkenes toward the synthesis of a series of ring-fused quinazolinones has been developed in moderate to excellent yields using commercially available ethers, alkanes, and alcohols, respectively, under a base-free condition in a short time without a transition metal as catalyst. Notably, the transformations can be carried out with the advantages of a broad substrate scope and high atomic economy. Density functional theory calculations and wavefunction analyses were performed to elucidate the radical reaction mechanism.
RESUMO
Although overexpression of EZH2, a catalytic subunit of the polycomb repressive complex 2 (PRC2), is an eminent feature of various cancers, the regulation of its abundance and function remains insufficiently understood. We report here that the PRC2 complex is physically associated with ubiquitin-specific protease USP7 in cancer cells where USP7 acts to deubiquitinate and stabilize EZH2. Interestingly, we found that USP7-catalyzed H2BK120ub1 deubiquitination is a prerequisite for chromatin loading of PRC2 thus H3K27 trimethylation, and this process is not affected by H2AK119 ubiquitination catalyzed by PRC1. Genome-wide analysis of the transcriptional targets of the USP7/PRC2 complex identified a cohort of genes including FOXO1 that are involved in cell growth and proliferation. We demonstrated that the USP7/PRC2 complex drives cancer cell proliferation and tumorigenesis in vitro and in vivo. We showed that the expression of both USP7 and EZH2 elevates during tumor progression, corresponding to a diminished FOXO1 expression, and the level of the expression of USP7 and EZH2 strongly correlates with histological grades and prognosis of tumor patients. These results reveal a dual role for USP7 in the regulation of the abundance and function of EZH2, supporting the pursuit of USP7 as a therapeutic target for cancer intervention.
Assuntos
Carcinogênese , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Complexo Repressor Polycomb 2/metabolismo , Peptidase 7 Específica de Ubiquitina/metabolismo , Animais , Feminino , Proteína Forkhead Box O1/metabolismo , Células HEK293 , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Células Sf9 , Ubiquitinação , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Long non-coding RNAs (LncRNAs) are implicated with tumorigenesis and the development of nasopharyngeal carcinoma (NPC). Previous studies suggested that long non-coding RNA small nucleolar RNA host gene 4 (SNHG4) exerted oncogenic roles in various cancers. However, the function and molecular mechanism of SNHG4 in NPC have not been investigated. In our study, it was confirmed that the SNHG4 level was enriched in NPC tissues and cells. Functional assays indicated that SNHG4 depletion inhibited the proliferation and metastasis but promoted apoptosis of NPC cells. Furthermore, we identified miR-510-5p as a downstream gene of SNHG4 in NPC cells and SNHG4 upregulated CENPF expression by binding to miR-510-5p. Moreover, there was a positive (or negative) association between CENPF and SNHG4 (or miR-510-5p) expression in NPC. In addition, rescue experiments verified that CENPF overexpression or miR-510-5p silencing abrogated inhibitory effects on NPC tumorigenesis caused by SNHG4 deficiency. The study demonstrated that SNHG4 promoted NPC progression via miR-510-5p/CENPF axis, providing a novel potential therapeutic target for NPC treatments.
Assuntos
MicroRNAs , Neoplasias Nasofaríngeas , RNA Longo não Codificante , Humanos , Carcinoma Nasofaríngeo/genética , RNA Longo não Codificante/genética , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Nucleolar Pequeno/genética , Neoplasias Nasofaríngeas/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Carcinogênese/genética , Fatores de Transcrição/genética , Regulação Neoplásica da Expressão GênicaRESUMO
A magnetically induced self-assembled graphene nanoribbons (GNRs) method is reported to synthesize MFe2O4/GNRs (M = Co,Ni). It is found that MFe2O4 compounds not only locate on the surface of GNRs but anchor on the interlayers of GNRs in the diameter of less than 5 nm as well. The in situ growth of MFe2O4 and magnetic aggregation at the joints of GNRs act as crosslinking agents to solder GNRs to build a nest structure. Additionally, combining GNRs with MFe2O4 helps to improve the magnetism of the MFe2O4. As an anode material for Li+ ion batteries, MFe2O4/GNRs can provide high reversible capacity and cyclic stability (1432 mAh g-1 for CoFe2O4/GNRs and 1058 mAh g-1 for NiFe2O4 at 0.1 A g-1 over 80 cycles).
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During interventional procedures,subjects are exposed to direct and scattered X-rays.Establishing diagnostic reference levels is an ideal way to optimize the radiation dose and reduce radiation hazard.In recent years,diagnostic reference levels in interventional radiology have been established in different countries.However,because of the too many indicators for characterizing the radiation dose,the indicators used to establish diagnostic reference levels vary in different countries.The research achievements in this field remain to be reviewed.We carried out a retrospective analysis of the definition,establishment method,application,and main factors influencing the dose difference of the diagnostic reference level,aiming to provide a basis for establishing the diagnostic reference level for interventional procedures in China.