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1.
Cell ; 172(5): 966-978.e12, 2018 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-29474922

RESUMO

Ebola virus nucleoprotein (eNP) assembles into higher-ordered structures that form the viral nucleocapsid (NC) and serve as the scaffold for viral RNA synthesis. However, molecular insights into the NC assembly process are lacking. Using a hybrid approach, we characterized the NC-like assembly of eNP, identified novel regulatory elements, and described how these elements impact function. We generated a three-dimensional structure of the eNP NC-like assembly at 5.8 Å using electron cryo-microscopy and identified a new regulatory role for eNP helices α22-α23. Biochemical, biophysical, and mutational analyses revealed that inter-eNP contacts within α22-α23 are critical for viral NC assembly and regulate viral RNA synthesis. These observations suggest that the N terminus and α22-α23 of eNP function as context-dependent regulatory modules (CDRMs). Our current study provides a framework for a structural mechanism for NC-like assembly and a new therapeutic target.


Assuntos
Microscopia Crioeletrônica , Ebolavirus/fisiologia , Ebolavirus/ultraestrutura , Nucleocapsídeo/ultraestrutura , Nucleoproteínas/ultraestrutura , Montagem de Vírus , Modelos Biológicos , Proteínas Mutantes/química , Mutação/genética , Nucleoproteínas/química , Multimerização Proteica , Estrutura Secundária de Proteína , Subunidades Proteicas/química , Subunidades Proteicas/metabolismo , RNA Viral/biossíntese , RNA Viral/química , RNA Viral/metabolismo
2.
Cancer Sci ; 115(3): 763-776, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38243657

RESUMO

Hepatocellular carcinoma (HCC) does not respond well to current treatments, even immune checkpoint inhibitors. PD-L1 (programmed cell death ligand 1 or CD274 molecule)-mediated immune escape of tumor cells may be a key factor affecting the efficacy of immune checkpoint inhibitor (ICI) therapy. However, the regulatory mechanisms of PD-L1 expression and immune escape require further exploration. Here, we observed that DDX1 (DEAD-box helicase 1) was overexpressed in HCC tissues and associated with poor prognosis in patients with HCC. Additionally, DDX1 expression correlated negatively with CD8+ T cell frequency. DDX1 overexpression significantly increased interferon gamma (IFN-γ)-mediated PD-L1 expression in HCC cell lines. DDX1 overexpression decreased IFN-γ and granzyme B production in CD8+ T cells and inhibited CD8+ T cell cytotoxic function in vitro and in vivo. In conclusion, DDX1 plays an essential role in developing the immune escape microenvironment, rendering it a potential predictor of ICI therapy efficacy in HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Antígeno B7-H1/metabolismo , Carcinoma Hepatocelular/metabolismo , Linfócitos T CD8-Positivos , RNA Helicases DEAD-box/metabolismo , Interferon gama/metabolismo , Neoplasias Hepáticas/metabolismo , Microambiente Tumoral
3.
Neurol Sci ; 45(6): 2825-2833, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38177969

RESUMO

OBJECTIVE: This is a retrospective analysis of clinical data from individuals diagnosed with neurosyphilis, aiming to enhance healthcare professionals' understanding of the disease and expedite early diagnosis and intervention. METHODS: A retrospective analysis was conducted on the clinical records of 50 patients who received a diagnosis of symptomatic neurosyphilis and were admitted to the Neurology Department during the period spanning January 2012 to December 2022. RESULTS: Clinical manifestations encompassed diverse phenotypes, with syphilitic meningitis accounting for 16% of cases, characterized by symptoms such as headache, blepharoptosis, paralysis, blurred vision, and tinnitus. Meningovascular syphilis presented in 36% of cases, exhibiting episodic loss of consciousness, limb numbness, and limb convulsion. Paralytic dementia manifested in 36% of cases, featuring symptoms such as memory loss, sluggish response, and slow movement. Tabes dorsalis was observed in 12% of cases, presenting with weakness, numbness, and staggering. Routine cerebrospinal fluid (CSF) analysis indicated abnormal white blood cell counts in 60% of patients, while biochemical testing revealed abnormal protein content in 52% of patients. Notably, statistically significant differences were observed between patients with interstitial and parenchymatous neurosyphilis (Z = 2.023, P = 0.044) in terms of CSF protein content. Electroencephalogram (EEG) results were abnormal in six patients, and imaging studies unveiled diverse findings in 46 patients. CONCLUSION: The study highlights the importance of neurological and/or ocular symptoms in diagnosing symptomatic neurosyphilis. Individuals with hypomnesia should be closely monitored for potential neurosyphilis. Integrating clinical manifestations, laboratory tests, EEG, and imaging can reduce misdiagnosis. This comprehensive approach shows promise in improving early identification and management of neurosyphilis.


Assuntos
Diagnóstico Precoce , Neurossífilis , Humanos , Neurossífilis/diagnóstico , Neurossífilis/complicações , Estudos Retrospectivos , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Idoso , Tabes Dorsal/diagnóstico , Tabes Dorsal/complicações
4.
Proc Natl Acad Sci U S A ; 118(17)2021 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-33875586

RESUMO

Coordinated beating is crucial for the function of multiple cilia. However, the molecular mechanism is poorly understood. Here, we characterize a conserved ciliary protein CYB5D1 with a heme-binding domain and a cordon-bleu ubiquitin-like domain. Mutation or knockdown of Cyb5d1 in zebrafish impaired coordinated ciliary beating in the otic vesicle and olfactory epithelium. Similarly, the two flagella of an insertional mutant of the CYB5D1 ortholog in Chlamydomonas (Crcyb5d1) showed an uncoordinated pattern due to a defect in the cis-flagellum. Biochemical analyses revealed that CrCYB5D1 is a radial spoke stalk protein that binds heme only under oxidizing conditions. Lack of CrCYB5D1 resulted in a reductive shift in flagellar redox state and slowing down of the phototactic response. Treatment of Crcyb5d1 with oxidants restored coordinated flagellar beating. Taken together, these data suggest that CrCYB5D1 may integrate environmental and intraciliary signals and regulate the redox state of cilia, which is crucial for the coordinated beating of multiple cilia.


Assuntos
Cílios/metabolismo , Cílios/fisiologia , Citocromos b5/metabolismo , Animais , Axonema/metabolismo , Chlamydomonas/metabolismo , Chlamydomonas/fisiologia , Citocromos b5/fisiologia , Dineínas/metabolismo , Flagelos/metabolismo , Flagelos/fisiologia , Proteínas Ligantes de Grupo Heme/metabolismo , Proteínas Ligantes de Grupo Heme/fisiologia , Microtúbulos/metabolismo , Mutação , Peixe-Zebra/metabolismo
5.
J Cell Sci ; 133(15)2020 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-32620698

RESUMO

Perturbation of spectrin-based membrane mechanics causes hereditary elliptocytosis and spinocerebellar ataxia, but the underlying cellular basis of pathogenesis remains unclear. Here, we introduced conserved disease-associated spectrin mutations into the Caenorhabditis elegans genome and studied the contribution of spectrin to neuronal migration and dendrite formation in developing larvae. The loss of spectrin resulted in ectopic actin polymerization outside of the existing front and secondary membrane protrusions, leading to defective neuronal positioning and dendrite morphology in adult animals. Spectrin accumulated in the lateral region and rear of migrating neuroblasts and redistributes from the soma into the newly formed dendrites, indicating that the spectrin-based membrane skeleton is asymmetric and remodels to regulate actin assembly and cell shape during development. We affinity-purified spectrin from C. elegans and showed that its binding partner ankyrin functions with spectrin. Asymmetry and remodeling of the membrane skeleton might enable spatiotemporal modulation of membrane mechanics for distinct developmental events.


Assuntos
Caenorhabditis elegans , Espectrina , Animais , Anquirinas , Caenorhabditis elegans/genética , Neurogênese , Esqueleto , Espectrina/genética
6.
Zhongguo Zhong Yao Za Zhi ; 47(4): 1051-1063, 2022 Feb.
Artigo em Zh | MEDLINE | ID: mdl-35285206

RESUMO

This study aimed to explore the anti-depressant components of Rehmanniae Radix and its action mechanism based on network pharmacology combined with molecular docking. The main components of Rehmanniae Radix were identified by ultra-high performance liquid chromatography-quadrupole/Orbitrap high resolution mass spectrometry(UPLC-Q-Orbitrap HRMS), and the related targets were predicted using SwissTargetPrediction. Following the collection of depression-related targets from GeneCards, OMIM and TTD, a protein-protein interaction(PPI) network was constructed using STRING. GO and KEGG pathway enrichment analysis was performed by Metascape. Cytoscape 3.7.2 was used to construct the networks of "components-targets-disease" and "components-targets-pathways", based on which the key targets and their corresponding components were obtained and then preliminarily verified by molecular docking. Rehmanniae Radix contained 85 components including iridoids, ionones, and phenylethanoid glycosides. The results of network analysis showed that the main anti-depressant components of Rehmanniae Radix were catalpol, melittoside, genameside C, gardoside, 6-O-p-coumaroyl ajugol, genipin-1-gentiobioside, jiocarotenoside A1, neo-rehmannioside, rehmannioside C, jionoside C, jionoside D, verbascoside, rehmannioside, cistanoside F, and leucosceptoside A, corresponding to the following 16 core anti-depression targets: AKT1, ALB, IL6, APP, MAPK1, CXCL8, VEGFA, TNF, HSP90 AA1, SIRT1, CNR1, CTNNB1, OPRM1, DRD2, ESR1, and SLC6 A4. As revealed by molecular docking, hydrogen bonding and hydrophobicity might be the main action forms. The key anti-depression targets of Rehmanniae Radix were concentrated in 24 signaling pathways, including neuroactive ligand-receptor interaction, neurodegenerative disease-multiple diseases pathway, phosphatidylinositol 3-kinase/protein kinase B pathway, serotonergic synapse, and Alzheimer's disease.


Assuntos
Medicamentos de Ervas Chinesas , Doenças Neurodegenerativas , Medicamentos de Ervas Chinesas/farmacologia , Humanos , Simulação de Acoplamento Molecular , Farmacologia em Rede , Extratos Vegetais , Rehmannia
7.
Plant Physiol ; 176(3): 1952-1964, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29288232

RESUMO

At present, only little is known about the enzymatic machinery required for N-glycosylation in Chlamydomonas reinhardtii, leading to the formation of N-glycans harboring Xyl and methylated Man. This machinery possesses new enzymatic features, as C. reinhardtii N-glycans are independent of ß1,2-N-acetylglucosaminyltransferase I. Here we have performed comparative N-glycoproteomic analyses of insertional mutants of mannosidase 1A (IM Man1A ) and xylosyltransferase 1A (IM XylT1A ). The disruption of man1A affected methylation of Man and the addition of terminal Xyl. The absence of XylT1A led to shorter N-glycans compared to the wild type. The use of a IM Man1A xIM XylT1A double mutant revealed that the absence of Man1A suppressed the IM XylT1A phenotype, indicating that the increased N-glycan trimming is regulated by core ß1,2-Xyl and is dependent on Man1A activity. These data point toward an enzymatic cascade in the N-glycosylation pathway of C. reinhardtii with interlinked roles of Man1A and XylT1A. The results described herein represent the first step toward a functional characterization of the enzymatic N-glycosylation machinery in C. reinhardtii.


Assuntos
Chlamydomonas reinhardtii/enzimologia , Chlamydomonas reinhardtii/genética , Glicoproteínas/metabolismo , Manosidases/genética , Mutação/genética , Pentosiltransferases/genética , Proteômica/métodos , Chlamydomonas reinhardtii/efeitos dos fármacos , Cruzamentos Genéticos , Testes Genéticos , Glicopeptídeos/metabolismo , Hexoses/farmacologia , Manosidases/metabolismo , Metilação , Mutagênese Insercional/genética , Polissacarídeos/química , Polissacarídeos/metabolismo , UDP Xilose-Proteína Xilosiltransferase
8.
Cells Tissues Organs ; 208(1-2): 13-24, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32045921

RESUMO

OBJECTIVE: The aim of this work was to determine the effect of miR-375 on chondrocyte metabolism and oxidative stress in osteoarthritis (OA) mouse models through the JAK2/STAT3 signaling pathway. METHODS: Chondrocytes were divided into control, IL-1ß, IL-1ß + miR-375 mimic, IL-1ß + miR-375 inhibitor, IL-1ß + miR-NC (negative control), and IL-1ß + miR-375 inhibitor + siJAK2 groups. The chondrocyte proliferation was determined by MTT assay, the superoxide dismutase (SOD) and malondialdehyde (MDA) levels by corresponding kits, and the chondrocyte apoptosis by TUNEL staining. Furthermore, OA mouse models were divided into Sham, OA + miR-NC, and OA + miRNA-375 antagomir groups. The pathological changes were observed, and the expressions of miR-375 and the JAK2/STAT3 pathway were determined by qRT-PCR and Western blotting, respectively. RESULTS: IL-1ß-induced chondrocytes had significant increases in miR-375 and MDA, with decreased proliferation and SOD levels, as compared to the control group. Meanwhile, they also exhibited elevated apoptosis, with upregulations of ADAMTS-5 and MMP-13 and downregulations of COL2A1 and ACAN, as well as decreased p-JAK2/JAK2, p-STAT3/STAT3, and Bcl-2/Bax. However, these changes were significantly improved after transfection with miR-375 inhibitor, but transfection with miR-375 mimic resulted in severer exacerbation. Notably, the improvement of miR-375 inhibitor could be abolished by transfection with siJAK2. Furthermore, miR-375 antagomir significantly alleviated OA progression in OA mice in vivo. CONCLUSION: MiR-375 suppression enhanced the ability of chondrocyte to antagonize the oxidative stress and maintained the homeostasis of extracellular matrix metabolism to protect chondrocytes from OA via activation of the JAK2/STAT3 pathway, indicating that miR-375 is a potential molecular target for OA treatment.


Assuntos
Condrócitos/patologia , MicroRNAs/metabolismo , Osteoartrite , Animais , Apoptose , Modelos Animais de Doenças , Desenvolvimento de Medicamentos , Interleucina-1beta/metabolismo , Janus Quinase 2/metabolismo , Camundongos , Osteoartrite/tratamento farmacológico , Osteoartrite/metabolismo , Estresse Oxidativo , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais
9.
J Virol ; 89(18): 9465-76, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26157117

RESUMO

UNLABELLED: Interferon-induced protein with tetratricopeptide repeats 1 (IFIT1) is a host protein with reported cell-intrinsic antiviral activity against several RNA viruses. The proposed basis for the activity against negative-sense RNA viruses is the binding to exposed 5'-triphosphates (5'-ppp) on the genome of viral RNA. However, recent studies reported relatively low binding affinities of IFIT1 for 5'-ppp RNA, suggesting that IFIT1 may not interact efficiently with this moiety under physiological conditions. To evaluate the ability of IFIT1 to have an impact on negative-sense RNA viruses, we infected Ifit1(-/-) and wild-type control mice and primary cells with four negative-sense RNA viruses (influenza A virus [IAV], La Crosse virus [LACV], Oropouche virus [OROV], and Ebola virus) corresponding to three distinct families. Unexpectedly, a lack of Ifit1 gene expression did not result in increased infection by any of these viruses in cell culture. Analogously, morbidity, mortality, and viral burdens in tissues were identical between Ifit1(-/-) and control mice after infection with IAV, LACV, or OROV. Finally, deletion of the human IFIT1 protein in A549 cells did not affect IAV replication or infection, and reciprocally, ectopic expression of IFIT1 in HEK293T cells did not inhibit IAV infection. To explain the lack of antiviral activity against IAV, we measured the binding affinity of IFIT1 for RNA oligonucleotides resembling the 5' ends of IAV gene segments. The affinity for 5'-ppp RNA was approximately 10-fold lower than that for non-2'-O-methylated (cap 0) RNA oligonucleotides. Based on this analysis, we conclude that IFIT1 is not a dominant restriction factor against negative-sense RNA viruses. IMPORTANCE: Negative-sense RNA viruses, including influenza virus and Ebola virus, have been responsible for some of the most deadly outbreaks in recent history. The host interferon response and induction of antiviral genes contribute to the control of infections by these viruses. IFIT1 is highly induced after virus infection and reportedly has antiviral activity against several RNA and DNA viruses. However, its role in restricting infection by negative-sense RNA viruses remains unclear. In this study, we evaluated the ability of IFIT1 to inhibit negative-sense RNA virus replication and pathogenesis both in vitro and in vivo. Detailed cell culture and animal studies demonstrated that IFIT1 is not a dominant restriction factor against three different families of negative-sense RNA viruses.


Assuntos
Proteínas de Transporte/metabolismo , Ebolavirus/metabolismo , Vírus da Influenza A/metabolismo , Vírus La Crosse/metabolismo , Infecções por Vírus de RNA/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Animais , Proteínas de Transporte/genética , Linhagem Celular , Ebolavirus/genética , Humanos , Vírus da Influenza A/genética , Vírus La Crosse/genética , Camundongos , Camundongos Knockout , Infecções por Vírus de RNA/genética , Proteínas de Ligação a RNA
10.
New Phytol ; 210(3): 934-45, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26781807

RESUMO

Cytoplasmic male sterility (CMS) and restoration of fertility (Rf) are widely distributed in plant species utilized by humans. RF5 and GRP162 are subunits of the restoration of fertility complex (RFC) in Hong-Lian rice. Despite the fact that the RFC is 400-500 kDa in size, the other proteins or factors in the complex still remain unknown. Here, we identified RFC subunit 3, which encodes a DUF1620-containing and WD40-like repeat protein (RFC3) that is present in all tissues but highly expressed in leaves. We established that RFC3 interacts with both RF5 and GRP162 in vitro and in vivo, and is transported into the mitochondria as a membrane protein. Furthermore, CMS RNA (atp6-orfH79) and CMS cytotoxic protein (ORFH79) accumulate when RFC3 is silenced in restorer lines. We presented the analysis with blue-native polyacrylamide gel electrophoresis, indicating that RFC is disrupted in the RNAi line. We concluded that RCF3 is indispensable as a scaffold protein for the assembly of the RFC complex. We unveil a new molecular player of the RFC in the Rf pathway in rice and propose the model of RFC based on these data.


Assuntos
Oryza/fisiologia , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Sequências Repetitivas de Aminoácidos , Sequência de Aminoácidos , Sequência Conservada , Fertilidade , Regulação da Expressão Gênica de Plantas , Inativação Gênica , Proteínas de Membrana/química , Proteínas de Membrana/metabolismo , Membranas Mitocondriais/metabolismo , Oryza/genética , Infertilidade das Plantas/genética , Plantas Geneticamente Modificadas , Ligação Proteica , Subunidades Proteicas/química , Subunidades Proteicas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Alinhamento de Sequência
11.
Molecules ; 21(10)2016 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-27669203

RESUMO

During a screening program for new agrochemicals from Chinese medicinal herbs, the ethanol extract of Notopterygium incisum rhizomes was found to possess strong nematicidal activity against the two species of nematodes, Bursaphelenchus xylophilus and Meloidogyne incognita. Based on bioactivity-guided fractionation, the four constituents were isolated from the ethanol extract and identified as columbianetin, falcarindiol, falcarinol, and isoimperatorin. Among the four isolated constituents, two acetylenic compounds, falcarindiol and falcarinol (2.20-12.60 µg/mL and 1.06-4.96 µg/mL, respectively) exhibited stronger nematicidal activity than two furanocoumarins, columbianetin, and isoimperatorin (21.83-103.44 µg/mL and 17.21-30.91 µg/mL, respectively) against the two species of nematodes, B. xylophilus and M. incognita. The four isolated constituents also displayed phototoxic activity against the nematodes. The results indicate that the ethanol extract of N. incisum and its four isolated constituents have potential for development into natural nematicides for control of plant-parasitic nematodes.


Assuntos
Apiaceae/química , Extratos Vegetais/farmacologia , Tylenchida/efeitos dos fármacos , Tylenchoidea/efeitos dos fármacos , Animais , Di-Inos/química , Medicamentos de Ervas Chinesas/farmacologia , Álcoois Graxos/química , Furocumarinas/química , Extratos Vegetais/química , Rizoma/química , Tylenchida/patogenicidade , Tylenchoidea/patogenicidade
12.
Plant Cell ; 24(1): 109-22, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22247252

RESUMO

The cytoplasmic male sterility (CMS) phenotype in plants can be reversed by the action of nuclear-encoded fertility restorer (Rf) genes. The molecular mechanism involved in Rf gene-mediated processing of CMS-associated transcripts is unclear, as are the identities of other proteins that may be involved in the CMS-Rf interaction. In this study, we cloned the restorer gene Rf5 for Hong-Lian CMS in rice and studied its fertility restoration mechanism with respect to the processing of the CMS-associated transcript atp6-orfH79. RF5, a pentatricopeptide repeat (PPR) protein, was unable to bind to this CMS-associated transcript; however, a partner protein of RF5 (GRP162, a Gly-rich protein encoding 162 amino acids) was identified to bind to atp6-orfH79. GRP162 was found to physically interact with RF5 and to bind to atp6-orfH79 via an RNA recognition motif. Furthermore, we found that RF5 and GRP162 are both components of a restoration of fertility complex (RFC) that is 400 to 500 kD in size and can cleave CMS-associated transcripts in vitro. Evidence that a PPR protein interacts directly with a Gly-rich protein to form a subunit of the RFC provides a new perspective on the molecular mechanisms underlying fertility restoration.


Assuntos
Oryza/metabolismo , Oryza/fisiologia , Infertilidade das Plantas/fisiologia , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Dados de Sequência Molecular , Oryza/genética , Infertilidade das Plantas/genética , Proteínas de Plantas/genética
13.
Proc Natl Acad Sci U S A ; 109(50): 20661-6, 2012 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-23185024

RESUMO

Filoviruses, marburgvirus (MARV) and ebolavirus (EBOV), are causative agents of highly lethal hemorrhagic fever in humans. MARV and EBOV share a common genome organization but show important differences in replication complex formation, cell entry, host tropism, transcriptional regulation, and immune evasion. Multifunctional filoviral viral protein (VP) 35 proteins inhibit innate immune responses. Recent studies suggest double-stranded (ds)RNA sequestration is a potential mechanism that allows EBOV VP35 to antagonize retinoic-acid inducible gene-I (RIG-I) like receptors (RLRs) that are activated by viral pathogen-associated molecular patterns (PAMPs), such as double-strandedness and dsRNA blunt ends. Here, we show that MARV VP35 can inhibit IFN production at multiple steps in the signaling pathways downstream of RLRs. The crystal structure of MARV VP35 IID in complex with 18-bp dsRNA reveals that despite the similar protein fold as EBOV VP35 IID, MARV VP35 IID interacts with the dsRNA backbone and not with blunt ends. Functional studies show that MARV VP35 can inhibit dsRNA-dependent RLR activation and interferon (IFN) regulatory factor 3 (IRF3) phosphorylation by IFN kinases TRAF family member-associated NFkb activator (TANK) binding kinase-1 (TBK-1) and IFN kB kinase e (IKKe) in cell-based studies. We also show that MARV VP35 can only inhibit RIG-I and melanoma differentiation associated gene 5 (MDA5) activation by double strandedness of RNA PAMPs (coating backbone) but is unable to inhibit activation of RLRs by dsRNA blunt ends (end capping). In contrast, EBOV VP35 can inhibit activation by both PAMPs. Insights on differential PAMP recognition and inhibition of IFN induction by a similar filoviral VP35 fold, as shown here, reveal the structural and functional plasticity of a highly conserved virulence factor.


Assuntos
Marburgvirus/imunologia , Marburgvirus/patogenicidade , Proteínas Virais Reguladoras e Acessórias/química , Proteínas Virais Reguladoras e Acessórias/imunologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Cristalografia por Raios X , Células HEK293 , Interações Hospedeiro-Patógeno , Humanos , Quinase I-kappa B/antagonistas & inibidores , Imunidade Inata , Interferon Tipo I/antagonistas & inibidores , Doença do Vírus de Marburg/etiologia , Doença do Vírus de Marburg/imunologia , Doença do Vírus de Marburg/virologia , Marburgvirus/química , Modelos Biológicos , Modelos Moleculares , Dados de Sequência Molecular , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Estrutura Terciária de Proteína , RNA/química , RNA/genética , RNA/metabolismo , Homologia de Sequência de Aminoácidos , Virulência/imunologia
14.
Yi Chuan ; 37(11): 1167-73, 2015 11.
Artigo em Zh | MEDLINE | ID: mdl-26582531

RESUMO

The RNA-guided CRISPR (clustered regularly interspaced short palindromic repeat)-associated Cas9 nuclease has offered a new platform for genome editing with high efficiency. Here, we report the use of CRISPR/Cas9 technology to target a specific genomic region in human pluripotent stem cells. We show that CRISPR/Cas9 can be used to disrupt a gene by introducing frameshift mutations to gene coding region; to knock in specific sequences (e.g. FLAG tag DNA sequence) to targeted genomic locus via homology directed repair; to induce large genomic deletion through dual-guide multiplex. Our results demonstrate the versatile application of CRISPR/Cas9 in stem cell genome editing, which can be widely utilized for functional studies of genes or genome loci in human pluripotent stem cells.


Assuntos
Sistemas CRISPR-Cas/genética , Genoma Humano/genética , Células-Tronco Pluripotentes/metabolismo , Edição de RNA , Mutação da Fase de Leitura , Humanos , RNA Guia de Cinetoplastídeos/genética
15.
Yi Chuan ; 37(10): 983-91, 2015 10.
Artigo em Inglês | MEDLINE | ID: mdl-26496750

RESUMO

Precision medicine emerges as a new approach that takes into account individual variability. The successful conduct of precision medicine requires the use of precise disease models. Human pluripotent stem cells (hPSCs), as well as adult stem cells, can be differentiated into a variety of human somatic cell types that can be used for research and drug screening. The development of genome editing technology over the past few years, especially the CRISPR/Cas system, has made it feasible to precisely and efficiently edit the genetic background. Therefore, disease modeling by using a combination of human stem cells and genome editing technology has offered a new platform to generate " personalized " disease models, which allow the study of the contribution of individual genetic variabilities to disease progression and the development of precise treatments. In this review, recent advances in the use of genome editing in human stem cells and the generation of stem cell models for rare diseases and cancers are discussed.


Assuntos
Sistemas CRISPR-Cas , Doença/genética , Engenharia Genética/métodos , Genoma Humano/genética , Medicina de Precisão/métodos , Células-Tronco/metabolismo , Humanos , Modelos Genéticos , Neoplasias/genética , Neoplasias/patologia , Medicina de Precisão/tendências , Doenças Raras/genética , Doenças Raras/patologia
16.
J Stroke Cerebrovasc Dis ; 23(6): 1500-5, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24630830

RESUMO

BACKGROUND: The relationship between anemia and intracerebral hemorrhage is not clear. We investigated the associations between anemia at the onset and mortality or dependency in patients with intracerebral hemorrhage (ICH) registered at the China National Stroke Registry (CNSR). METHODS: The CNSR recruited consecutive patients with diagnoses of ICH in 2007-2008. Their vascular risk factors, clinical presentations, and outcomes were recorded. The mortality and dependency at 1, 3, and 6 months and at 1 year were compared between ICH patients with and without anemia. A favorable outcome was defined as a modified Rankin Scale (mRS) score of 2 or less and a poor outcome as an mRS score of 3 or more. Multivariable logistic regression was performed to analyze the association between anemia and the 2 outcomes after adjusting for age, gender, body mass index, history of smoking and heavy drinking, National Institutes of Health Stroke Scale score on admission, random glucose value on admission, and hematoma volume. RESULTS: Anemia was identified in 484 (19%) ICH patients. Compared with ICH patients without anemia, patients with anemia had no difference in mortality rate at discharge and at 1 month. The rate of mortality at 3 months, 6 months, 1 year, and dependency at 1 year were significantly higher for those patients with anemia than those without (P<.05, P<.001, P<.001, and P<.05, respectively). After adjusting for potential confounders, anemia was an independent risk factor for death at 6 months and 1 year (adjusted odds ratio [OR]=1.338, 95% confidence interval 1.01-1.78, and adjusted OR=1.326, 95% confidence interval 1.00-1.75) in ICH patients. CONCLUSIONS: Anemia independently predicted mortality at 6 months and 1 year after the initial episode of intercerebral hemorrhage.


Assuntos
Anemia/mortalidade , Hemorragias Intracranianas/mortalidade , Acidente Vascular Cerebral/mortalidade , Idoso , Anemia/complicações , China , Feminino , Humanos , Hemorragias Intracranianas/complicações , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Sistema de Registros , Risco , Acidente Vascular Cerebral/complicações
17.
Cancer Lett ; 598: 217114, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38992488

RESUMO

Gender plays a crucial role in the occurrence and development of cancer, as well as in the metabolism of nutrients and energy. Men and women display significant differences in the incidence, prognosis, and treatment response across various types of cancer, including certain sex-specific tumors. It has been observed that male glioma patients have a higher incidence and worse prognosis than female patients, but there is currently a limited systematic evaluation of sex differences in gliomas. The purpose of this study is to provide an overview of the association between fluctuations in sex hormone levels and changes in their receptor expression with the incidence, progression, treatment, and prognosis of gliomas. Estrogen may have a protective effect on glioma patients, while exposure to androgens increases the risk of glioma. We also discussed the specific genetic and molecular differences between genders in terms of the malignant nature and prognosis of gliomas. Factors such as TP53, MGMT methylation status may play a crucial role. Therefore, it is essential to consider the gender of patients while treating glioma, particularly the differences at the hormonal and molecular levels. This approach can help in the adoption of an individualized treatment strategy.

18.
Nat Commun ; 15(1): 427, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38199995

RESUMO

The microbiome in a specific human organ has been well-studied, but few reports have investigated the multi-organ microbiome as a whole. Here, we aim to analyse the intra-individual inter-organ and intra-organ microbiome in deceased humans. We collected 1608 samples from 53 sites of 7 surface organs (oral cavity, esophagus, stomach, small intestine, appendix, large intestine and skin; n = 33 subjects) and performed microbiome profiling, including 16S full-length sequencing. Microbial diversity varied dramatically among organs, and core microbial species co-existed in different intra-individual organs. We deciphered microbial changes across distinct intra-organ sites, and identified signature microbes, their functional traits, and interactions specific to each site. We revealed significant microbial heterogeneity between paired mucosa-lumen samples of stomach, small intestine, and large intestine. Finally, we established the landscape of inter-organ relationships of microbes along the digestive tract. Therefore, we generate a catalogue of bacterial composition, diversity, interaction, functional traits, and bacterial translocation in human at inter-organ and intra-organ levels.


Assuntos
Apêndice , Microbiota , Humanos , Translocação Bacteriana , Estômago , Microbiota/genética , Boca
19.
United European Gastroenterol J ; 12(6): 772-779, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38753528

RESUMO

OBJECTIVES: Detection of early neoplastic lesions is crucial for improving the survival rates of patients with gastric cancer. Optical enhancement mode 2 is a new image-enhanced endoscopic technique that offers bright images and can improve the visibility of neoplastic lesions. This study aimed to compare the detection of neoplastic lesions with optical enhancement mode 2 and white-light imaging (WLI) in a high-risk population. METHODS: In this prospective multicenter randomized controlled trial, patients were randomly assigned to optical enhancement mode 2 or WLI groups. Detection of suspicious neoplastic lesions during the examinations was recorded, and pathological diagnoses served as the gold standard. RESULTS: A total of 1211 and 1219 individuals were included in the optical enhancement mode 2 and WLI groups, respectively. The detection rate of neoplastic lesions was significantly higher in the optical enhancement mode 2 group (5.1% vs. 1.9%; risk ratio, 2.656 [95% confidence interval, 1.630-4.330]; p < 0.001). The detection rate of neoplastic lesions with an atrophic gastritis background was significantly higher in the optical enhancement mode 2 group (8.6% vs. 2.6%, p < 0.001). The optical enhancement mode 2 group also had a higher detection rate among endoscopists with different experiences. CONCLUSIONS: Optical enhancement mode 2 was more effective than WLI for detecting neoplastic lesions in the stomach, and can serve as a new method for screening early gastric cancer in clinical practice. CLINICAL REGISTRY: United States National Library of Medicine (https://www. CLINICALTRIALS: gov), ID: NCT040720521.


Assuntos
Detecção Precoce de Câncer , Gastroscopia , Aumento da Imagem , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/diagnóstico por imagem , Neoplasias Gástricas/patologia , Neoplasias Gástricas/diagnóstico , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Prospectivos , Gastroscopia/métodos , Detecção Precoce de Câncer/métodos , Idoso , Aumento da Imagem/métodos , Gastrite Atrófica/diagnóstico , Gastrite Atrófica/patologia , Gastrite Atrófica/diagnóstico por imagem , Adulto
20.
Biochemistry ; 52(47): 8406-19, 2013 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-24067086

RESUMO

Viral protein 35 (VP35), encoded by filoviruses, is a multifunctional dsRNA binding protein that plays important roles in viral replication, innate immune evasion, and pathogenesis. The multifunctional nature of these proteins also presents opportunities to develop countermeasures that target distinct functional regions. However, functional validation and the establishment of therapeutic approaches toward such multifunctional proteins, particularly for nonenzymatic targets, are often challenging. Our previous work on filoviral VP35 proteins defined conserved basic residues located within its C-terminal dsRNA binding interferon (IFN) inhibitory domain (IID) as important for VP35 mediated IFN antagonism and viral polymerase cofactor functions. In the current study, we used a combination of structural and functional data to determine regions of Ebola virus (EBOV) VP35 (eVP35) to target for aptamer selection using SELEX. Select aptamers, representing, two distinct classes, were further characterized based on their interaction properties to eVP35 IID. These results revealed that these aptamers bind to distinct regions of eVP35 IID with high affinity (10-50 nM) and specificity. These aptamers can compete with dsRNA for binding to eVP35 and disrupt the eVP35-nucleoprotein (NP) interaction. Consistent with the ability to antagonize the eVP35-NP interaction, select aptamers can inhibit the function of the EBOV polymerase complex reconstituted by the expression of select viral proteins. Taken together, our results support the identification of two aptamers that bind filoviral VP35 proteins with high affinity and specificity and have the capacity to potentially function as filoviral VP35 protein inhibitors.


Assuntos
Antivirais/química , Aptâmeros de Nucleotídeos/química , RNA/química , Proteínas Virais Reguladoras e Acessórias/antagonistas & inibidores , Sequência de Aminoácidos , Antivirais/metabolismo , Antivirais/farmacologia , Aptâmeros de Nucleotídeos/metabolismo , Aptâmeros de Nucleotídeos/farmacologia , Ligação Competitiva , Sequência Conservada , Ebolavirus/efeitos dos fármacos , Ebolavirus/metabolismo , Doença pelo Vírus Ebola/tratamento farmacológico , Doença pelo Vírus Ebola/metabolismo , Cinética , Terapia de Alvo Molecular , Proteínas Mutantes/antagonistas & inibidores , Proteínas Mutantes/química , Proteínas Mutantes/metabolismo , Conformação de Ácido Nucleico , Nucleoproteínas/metabolismo , Conformação Proteica , Domínios e Motivos de Interação entre Proteínas , RNA/metabolismo , RNA/farmacologia , RNA de Cadeia Dupla/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Técnica de Seleção de Aptâmeros , Especificidade da Espécie , Proteínas Virais Reguladoras e Acessórias/química , Proteínas Virais Reguladoras e Acessórias/genética , Proteínas Virais Reguladoras e Acessórias/metabolismo
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