Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 235
Filtrar
1.
Mol Cell ; 82(21): 4018-4032.e9, 2022 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-36332605

RESUMO

Kinetochore assembly on centromeres is central for chromosome segregation, and defects in this process cause mitotic errors and aneuploidy. Besides the well-established protein network, emerging evidence suggests the involvement of regulatory RNA in kinetochore assembly; however, it has remained elusive about the identity of such RNA, let alone its mechanism of action in this critical process. Here, we report CCTT, a previously uncharacterized long non-coding RNA (lncRNA) transcribed from the arm of human chromosome 17, which plays a vital role in kinetochore assembly. We show that CCTT highly localizes to all centromeres via the formation of RNA-DNA triplex and specifically interacts with CENP-C to help engage this blueprint protein in centromeres, and consequently, CCTT loss triggers extensive mitotic errors and aneuploidy. These findings uncover a non-centromere-derived lncRNA that recruits CENP-C to centromeres and shed critical lights on the function of centromeric DNA sequences as anchor points for kinetochore assembly.


Assuntos
RNA Longo não Codificante , Humanos , Aneuploidia , Proteína Centromérica A/metabolismo , DNA , Cinetocoros/metabolismo , RNA Longo não Codificante/genética , Centrômero
2.
J Immunol ; 212(7): 1207-1220, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38345351

RESUMO

Teleost fish type I IFNs and the associated receptors from the cytokine receptor family B (CRFB) are characterized by remarkable diversity and complexity. How the fish type I IFNs bind to their receptors is still not fully understood. In this study, we demonstrate that CRFB1 and CRFB5 constitute the receptor pair through which type I subgroup d IFN (IFNd) from large yellow croaker, Larimichthys crocea, activates the conserved JAK-STAT signaling pathway as a part of the antiviral response. Our data suggest that L. crocea IFNd (LcIFNd) has a higher binding affinity with L. crocea CRFB5 (LcCRFB5) than with LcCRFB1. Furthermore, we report the crystal structure of LcIFNd at a 1.49-Å resolution and construct structural models of LcIFNd in binary complexes with predicted structures of extracellular regions of LcCRFB1 and LcCRFB5, respectively. Despite striking similarities in overall architectures of LcIFNd and its ortholog human IFN-ω, the receptor binding patterns between LcIFNd and its receptors show that teleost and mammalian type I IFNs may have differentially selected helices that bind to their homologous receptors. Correspondingly, key residues mediating binding of LcIFNd to LcCRFB1 and LcCRFB5 are largely distinct from the receptor-interacting residues in other fish and mammalian type I IFNs. Our findings reveal a ligand/receptor complex binding mechanism of IFNd in teleost fish, thus providing new insights into the function and evolution of type I IFNs.


Assuntos
Interferon Tipo I , Perciformes , Animais , Humanos , Filogenia , Peixes/metabolismo , Interferon Tipo I/metabolismo , Proteínas de Peixes/genética , Mamíferos/metabolismo
3.
Proc Natl Acad Sci U S A ; 120(49): e2306390120, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38015841

RESUMO

Hepatitis B virus (HBV) remains a major public health threat with nearly 300 million people chronically infected worldwide who are at a high risk of developing hepatocellular carcinoma. Current therapies are effective in suppressing HBV replication but rarely lead to cure. Current therapies do not affect the HBV covalently closed circular DNA (cccDNA), which serves as the template for viral transcription and replication and is highly stable in infected cells to ensure viral persistence. In this study, we aim to identify and elucidate the functional role of cccDNA-associated host factors using affinity purification and protein mass spectrometry in HBV-infected cells. Nucleolin was identified as a key cccDNA-binding protein and shown to play an important role in HBV cccDNA transcription, likely via epigenetic regulation. Targeting nucleolin to silence cccDNA transcription in infected hepatocytes may be a promising therapeutic strategy for a functional cure of HBV.


Assuntos
Hepatite B , Neoplasias Hepáticas , Humanos , Vírus da Hepatite B/fisiologia , Epigênese Genética , Replicação Viral/genética , DNA Viral/metabolismo , DNA Circular/genética , DNA Circular/metabolismo , Neoplasias Hepáticas/genética , Hepatite B/genética , Hepatite B/metabolismo , Nucleolina
4.
PLoS Pathog ; 19(5): e1011382, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37224147

RESUMO

Hepatitis B virus (HBV) chronically infects 296 million individuals and there is no cure. As an important step of viral life cycle, the mechanisms of HBV egress remain poorly elucidated. With proteomic approach to identify capsid protein (HBc) associated host factors and siRNA screen, we uncovered tumor susceptibility gene 101 (TSG101). Knockdown of TSG101 in HBV-producing cells, HBV-infected cells and HBV transgenic mice suppressed HBV release. Co-immunoprecipitation and site mutagenesis revealed that VFND motif in TSG101 and Lys-96 ubiquitination in HBc were essential for TSG101-HBc interaction. In vitro ubiquitination experiment demonstrated that UbcH6 and NEDD4 were potential E2 ubiquitin-conjugating enzyme and E3 ligase that catalyzed HBc ubiquitination, respectively. PPAY motif in HBc and Cys-867 in NEDD4 were required for HBc ubiquitination, TSG101-HBc interaction and HBV egress. Transmission electron microscopy confirmed that TSG101 or NEDD4 knockdown reduces HBV particles count in multivesicular bodies (MVBs). Our work indicates that TSG101 recognition for NEDD4 ubiquitylated HBc is critical for MVBs mediated HBV egress.


Assuntos
Vírus da Hepatite B , Proteômica , Animais , Camundongos , Vírus da Hepatite B/genética , Fatores de Transcrição/genética , Proteínas de Ligação a DNA/genética , Camundongos Transgênicos
5.
J Biol Chem ; 299(9): 105151, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37567479

RESUMO

Hepatitis B virus (HBV) is a hepatotropic DNA virus that has a very compact genome. Due to this genomic density, several distinct mechanisms are used to facilitate the viral life cycle. Recently, accumulating evidence show that G-quadruplex (G4) in different viruses play essential regulatory roles in key steps of the viral life cycle. Although G4 structures in the HBV genome have been reported, their function in HBV replication remains elusive. In this study, we treated an HBV replication-competent cell line and HBV-infected cells with the G4 structure stabilizer pyridostatin (PDS) and evaluated different HBV replication markers to better understand the role played by the G4. In both models, we found PDS had no effect on viral precore RNA (pcRNA) or pre-genomic RNA (pgRNA), but treatment did increase HBeAg/HBc ELISA reads and intracellular levels of viral core/capsid protein (HBc) in a dose-dependent manner, suggesting post-transcriptional regulation. To further dissect the mechanism of G4 involvement, we used in vitro-synthesized HBV pcRNA and pgRNA. Interestingly, we found PDS treatment only enhanced HBc expression from pgRNA but not HBeAg expression from pcRNA. Our bioinformatic analysis and CD spectroscopy revealed that pgRNA harbors a conserved G4 structure. Finally, we introduced point mutations in pgRNA to disrupt its G4 structure and observed the resulting mutant failed to respond to PDS treatment and decreased HBc level in in vitro translation assay. Taken together, our data demonstrate that HBV pgRNA contains a G4 structure that plays a vital role in the regulation of viral mRNA translation.


Assuntos
Quadruplex G , Vírus da Hepatite B , Hepatite B , Humanos , Proteínas do Capsídeo/química , Proteínas do Capsídeo/metabolismo , Hepatite B/virologia , Antígenos E da Hepatite B/metabolismo , Vírus da Hepatite B/genética , Vírus da Hepatite B/metabolismo , RNA Viral/genética , RNA Viral/metabolismo , Proteínas do Core Viral/química , Proteínas do Core Viral/metabolismo , Replicação Viral/genética , Linhagem Celular , Quadruplex G/efeitos dos fármacos , Biossíntese de Proteínas/efeitos dos fármacos , Biossíntese de Proteínas/genética , Mutação , Aminoquinolinas/farmacologia
6.
J Virol ; 97(7): e0051223, 2023 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-37347173

RESUMO

Nonstructural protein 13 (nsp13), the helicase of SARS-CoV-2, has been shown to possess multiple functions that are essential for viral replication, and is considered an attractive target for the development of novel antivirals. We were initially interested in the interplay between nsp13 and interferon (IFN) signaling, and found that nsp13 inhibited reporter signal in an IFN-ß promoter assay. Surprisingly, the ectopic expression of different components of the RIG-I/MDA5 pathway, which were used to stimulate IFN-ß promoter, was also mitigated by nsp13. However, endogenous expression of these genes was not affected by nsp13. Interestingly, nsp13 restricted the expression of foreign genes originating from plasmid transfection, but failed to inhibit them after chromosome integration. These data, together with results from a runoff transcription assay and RNA sequencing, suggested a specific inhibition of episomal but not chromosomal gene transcription by nsp13. By using different truncated and mutant forms of nsp13, we demonstrated that its NTPase and helicase activities contributed to the inhibition of episomal DNA transcription, and that this restriction required direct interaction with episomal DNA. Based on these findings, we developed an economical and convenient high-throughput drug screening method targeting nsp13. We evaluated the inhibitory effects of various compounds on nsp13 by the expression of reporter gene plasmid after co-transfection with nsp13. In conclusion, we found that nsp13 can specifically inhibit episomal DNA transcription and developed a high-throughput drug screening method targeting nsp13 to facilitate the development of new antiviral drugs. IMPORTANCE To combat COVID-19, we need to understand SARS-CoV-2 and develop effective antiviral drugs. In our study, we serendipitously found that SARS-CoV-2 nsp13 could suppress episomal DNA transcription without affecting chromosomal DNA. Detailed characterization revealed that nsp13 suppresses episomal gene expression through its NTPase and helicase functions following DNA binding. Furthermore, we developed a high-throughput drug screening system targeting SARS-CoV-2 nsp13. Compared to traditional SARS-CoV-2 drug screening methods, our system is more economical and convenient, facilitating the development of more potent and selective nsp13 inhibitors and enabling the discovery of new antiviral therapies.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , Nucleosídeo-Trifosfatase/genética , RNA Helicases/metabolismo , Proteínas não Estruturais Virais/metabolismo , DNA Helicases/genética , DNA Helicases/metabolismo , Antivirais/farmacologia , DNA , Plasmídeos/genética
7.
Hepatology ; 77(4): 1366-1381, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35718932

RESUMO

BACKGROUND AND AIMS: Murine hepatic cells cannot support hepatitis B virus (HBV) infection even with supplemental expression of viral receptor, human sodium taurocholate cotransporting polypeptide (hNTCP). However, the specific restricted step remains elusive. In this study, we aimed to dissect HBV infection process in murine hepatic cells. APPROACH AND RESULTS: Cells expressing hNTCP were inoculated with HBV or hepatitis delta virus (HDV). HBV pregenomic RNA (pgRNA), covalently closed circular DNA (cccDNA), and different relaxed circular DNA (rcDNA) intermediates were produced in vitro . The repair process from rcDNA to cccDNA was assayed by in vitro repair experiments and in mouse with hydrodynamic injection. Southern blotting and in situ hybridization were used to detect HBV DNA. HBV, but not its satellite virus HDV, was restricted from productive infection in murine hepatic cells expressing hNTCP. Transfection of HBV pgRNA could establish HBV replication in human, but not in murine, hepatic cells. HBV replication-competent plasmid, cccDNA, and recombinant cccDNA could support HBV transcription in murine hepatic cells. Different rcDNA intermediates could be repaired to form cccDNA both in vitro and in vivo . In addition, rcDNA could be detected in the nucleus of murine hepatic cells, but cccDNA could not be formed. Interestingly, nuclease sensitivity assay showed that the protein-linked rcDNA isolated from cytoplasm was completely nuclease resistant in murine, but not in human, hepatic cells. CONCLUSIONS: Our results imply that the disassembly of cytoplasmic HBV nucleocapsids is restricted in murine hepatic cells. Overcoming this limitation may help to establish an HBV infection mouse model.


Assuntos
Vírus da Hepatite B , Hepatite B , Camundongos , Humanos , Animais , Vírus da Hepatite B/genética , Vírus da Hepatite B/metabolismo , DNA Viral/genética , Replicação Viral/genética , Hepatócitos/metabolismo , Nucleocapsídeo/metabolismo , Hepatite B/genética , Citoplasma/metabolismo , DNA Circular/metabolismo
8.
Respir Res ; 25(1): 14, 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38178075

RESUMO

BACKGROUND: Ambient fine particulate matter (PM2.5) is considered a plausible contributor to the onset of chronic obstructive pulmonary disease (COPD). Mechanistic studies are needed to augment the causality of epidemiologic findings. In this study, we aimed to test the hypothesis that repeated exposure to diesel exhaust particles (DEP), a model PM2.5, causes COPD-like pathophysiologic alterations, consequently leading to the development of specific disease phenotypes. Sprague Dawley rats, representing healthy lungs, were randomly assigned to inhale filtered clean air or DEP at a steady-state concentration of 1.03 mg/m3 (mass concentration), 4 h per day, consecutively for 2, 4, and 8 weeks, respectively. Pulmonary inflammation, morphologies and function were examined. RESULTS: Black carbon (a component of DEP) loading in bronchoalveolar lavage macrophages demonstrated a dose-dependent increase in rats following DEP exposures of different durations, indicating that DEP deposited and accumulated in the peripheral lung. Total wall areas (WAt) of small airways, but not of large airways, were significantly increased following DEP exposures, compared to those following filtered air exposures. Consistently, the expression of α-smooth muscle actin (α-SMA) in peripheral lung was elevated following DEP exposures. Fibrosis areas surrounding the small airways and content of hydroxyproline in lung tissue increased significantly following 4-week and 8-week DEP exposure as compared to the filtered air controls. In addition, goblet cell hyperplasia and mucus hypersecretions were evident in small airways following 4-week and 8-week DEP exposures. Lung resistance and total lung capacity were significantly increased following DEP exposures. Serum levels of two oxidative stress biomarkers (MDA and 8-OHdG) were significantly increased. A dramatical recruitment of eosinophils (14.0-fold increase over the control) and macrophages (3.2-fold increase) to the submucosa area of small airways was observed following DEP exposures. CONCLUSIONS: DEP exposures over the courses of 2 to 8 weeks induced COPD-like pathophysiology in rats, with characteristic small airway remodeling, mucus hypersecretion, and eosinophilic inflammation. The results provide insights on the pathophysiologic mechanisms by which PM2.5 exposures cause COPD especially the eosinophilic phenotype.


Assuntos
Poluentes Atmosféricos , Doença Pulmonar Obstrutiva Crônica , Ratos , Animais , Material Particulado/toxicidade , Material Particulado/análise , Emissões de Veículos/toxicidade , Poluentes Atmosféricos/toxicidade , Poluentes Atmosféricos/análise , Ratos Sprague-Dawley , Doença Pulmonar Obstrutiva Crônica/induzido quimicamente
9.
Exp Dermatol ; 33(2): e15018, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38414007

RESUMO

Ferroptosis, a type of programmed cell death, occurs when there is oxidative stress and lipid peroxides. This condition is marked by lipid peroxidation that relies on iron and the reduction of cellular defences against oxidation. To investigate the effect of UVB irradiation on ferroptosis of human keratinocytes HaCaT cells, the cells were pretreated with Ferrostatin 1 (Fer-1, 10 µM), an ferroptosis inhibitor and then irradiated with UVB (20 mJ/cm2 ) for 30 min to detect related indexes of ferroptosis through MTT assay, quantitative real-time polymerase chain reaction, flow cytometry, reactive oxygen species (ROS) assay, western blotting. Results showed that UVB significantly reduced cell activity, promoted apoptosis and ROS level, whereas Fer-1 significantly increased cell activity, and reduced apoptosis and ROS level. In addition, UVB significantly reduced levels of ferroptosis-related proteins and skin barrier-related proteins, and increased levels of γ-H2AX and iron, whereas Fer-1 significantly increased their protein levels, and reduced levels of γ-H2AX and iron. Conjoint analysis of transcriptomic and proteomic revealed that UVB significantly reduced the levels of TIMP metallopeptidase inhibitor 3 (TIMP3), and coagulation factor II thrombin receptor (F2R), whereas Fer-1 significantly promoted the levels of TIMP3, and F2R. Therefore, our results indicated that Fer-1 significantly ameliorates UVB-induced damage of HaCaT cells by regulating the levels of TIMP3 and F2R.


Assuntos
Ferroptose , Células HaCaT , Humanos , Espécies Reativas de Oxigênio/metabolismo , Proteômica , Apoptose , Queratinócitos/metabolismo , Ferro , Raios Ultravioleta/efeitos adversos
10.
Int J Mol Sci ; 25(9)2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38731886

RESUMO

The cerebrovascular endothelial cells with distinct characteristics line cerebrovascular blood vessels and are the fundamental structure of the blood-brain barrier, which is important for the development and homeostatic maintenance of the central nervous system. Cre-LoxP system-based spatial gene manipulation in mice is critical for investigating the physiological functions of key factors or signaling pathways in cerebrovascular endothelial cells. However, there is a lack of Cre recombinase mouse lines that specifically target cerebrovascular endothelial cells. Here, using a publicly available single-cell RNAseq database, we screened the solute carrier organic anion transporter family member 1a4 (Slco1a4) as a candidate marker of cerebrovascular endothelial cells. Then, we generated an inducible Cre mouse line in which a CreERT2-T2A-tdTomato cassette was placed after the initiation codon ATG of the Slco1a4 locus. We found that tdTomato, which can indicate the endogenous Slco1a4 expression, was expressed in almost all cerebrovascular endothelial cells but not in any other non-endothelial cell types in the brain, including neurons, astrocytes, oligodendrocytes, pericytes, smooth muscle cells, and microglial cells, as well as in other organs. Consistently, when crossing the ROSA26LSL-EYFP Cre reporter mouse, EYFP also specifically labeled almost all cerebrovascular endothelial cells upon tamoxifen induction. Overall, we generated a new inducible Cre line that specifically targets cerebrovascular endothelial cells.


Assuntos
Encéfalo , Células Endoteliais , Integrases , Animais , Camundongos , Células Endoteliais/metabolismo , Integrases/metabolismo , Integrases/genética , Encéfalo/metabolismo , Técnicas de Introdução de Genes , Camundongos Transgênicos , Barreira Hematoencefálica/metabolismo , Transportadores de Ânions Orgânicos/genética , Transportadores de Ânions Orgânicos/metabolismo , Tamoxifeno/farmacologia , Proteína Vermelha Fluorescente
11.
Sci Eng Ethics ; 30(3): 26, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38856788

RESUMO

The rapid development of computer vision technologies and applications has brought forth a range of social and ethical challenges. Due to the unique characteristics of visual technology in terms of data modalities and application scenarios, computer vision poses specific ethical issues. However, the majority of existing literature either addresses artificial intelligence as a whole or pays particular attention to natural language processing, leaving a gap in specialized research on ethical issues and systematic solutions in the field of computer vision. This paper utilizes bibliometrics and text-mining techniques to quantitatively analyze papers from prominent academic conferences in computer vision over the past decade. It first reveals the developing trends and specific distribution of attention regarding trustworthy aspects in the computer vision field, as well as the inherent connections between ethical dimensions and different stages of visual model development. A life-cycle framework regarding trustworthy computer vision is then presented by making the relevant trustworthy issues, the operation pipeline of AI models, and viable technical solutions interconnected, providing researchers and policymakers with references and guidance for achieving trustworthy CV. Finally, it discusses particular motivations for conducting trustworthy practices and underscores the consistency and ambivalence among various trustworthy principles and technical attributes.


Assuntos
Inteligência Artificial , Humanos , Inteligência Artificial/ética , Inteligência Artificial/tendências , Confiança , Processamento de Linguagem Natural , Mineração de Dados/ética , Bibliometria
12.
BMC Nurs ; 23(1): 154, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38438961

RESUMO

BACKGROUND: Clinical nurses play an important role in ensuring patient safety. Nurses' work experience, organizational environment, psychological cognition, and behavior can all lead to patient safety issues. Improving nurses' attention to patient safety issues and enhancing their competence in dealing with complex medical safety issues can help avoid preventable nursing adverse events. Therefore, it is necessary to actively identify the latent profiles of patient safety competency of clinical nurses and to explore the influencing factors. METHODS: A cross-sectional design was conducted. A total of 782 Chinese registered nurses were included in the study. Demographic characteristics questionnaire, Error Management Climate scale, Security Questionnaire, Proactive Behavior Performance scale and Patient Safety Competency Self-Rating Scale of Nurses were used. Latent profile analysis (LPA) was performed to categorize nurses into latent subgroups with patient safety competency differences. Multinomial logistic regression was conducted to explore the influencing factors of nurses' patient safety competency (PSC) in different latent profiles. RESULTS: A total of 782 questionnaires were valid. Nurses' PSC was positively related to error management climate, and psychological safety and proactive behavior. The PSC score was 121.31 (SD = 19.51), showing that the PSC of clinical nurses was at the level of the medium on the high side. The error management climate score was 70.28 (SD = 11.93), which was at a relatively high level. The psychological safety score was 61.21 (SD = 13.44), indicating a moderate to low level. The proactive behavior score was 37.60 (SD = 7.33), which was at a high level. The latent profile analysis result showed that three groups of profile models were fitted acceding to the evaluation of PSC. They were defined as Low-competency Group (74 (9.5%)), Medium-competency Group (378 (48.3%)) and High-competency Group (330 (42.2%). Working years, professional titles, departments, error management climate, psychological security and proactive behavior were the influencing factors of PSC in three latent profiles. CONCLUSIONS: The PSC of clinical nurses had obvious classification characteristics, and the main influencing factors were working years, professional titles, working departments, error management climate, psychological security and proactive behavior. This study suggests that managers should pay attention to the continuous cultivation of patient safety competence among clinical nurses, provide targeted intervention measures for nurses at different work stages, professional titles, and departments, and use efficient management strategies to create a positive error management atmosphere. In patient safety management, providing nurses with more psychological security is conducive to stimulating more proactive behaviors and continuously improving the level of patient safety competence.

13.
Biochem Biophys Res Commun ; 659: 40-45, 2023 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-37031593

RESUMO

The O-carbamoyltransferase VtdB catalyzes the carbamoylation of venturicidin B, which is essential for the biosynthesis of the antibiotic venturicidin A. Here, the crystal structures of VtdB and VtdB in complex with the intermediate carbamoyladenylate (VtdBCAO) were determined at resolutions of 2.99 Å and 2.90 Å, respectively. The structures resemble the conserved YrdC-like and specific Kae1-like domains. A magnesium ion and the intermediate carbamoyladenylate were also observed in the Kae1-like domain of VtdB. The structure of VtdBCAO in complex with the substrate venturicidin B was modeled by a molecular docking method to better understand the substrate binding mode, revealing a novel venturicidin B binding pocket.


Assuntos
Streptomyces , Simulação de Acoplamento Molecular , Sítios de Ligação , Cristalografia por Raios X , Especificidade por Substrato
14.
J Virol ; 96(21): e0136222, 2022 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-36226986

RESUMO

Hepatitis B virus (HBV) infection is a major health burden worldwide, and currently there is no cure. The persistence of HBV covalently closed circular DNA (cccDNA) is the major obstacle for antiviral trement. HBV core protein (HBc) has emerged as a promising antiviral target, as it plays important roles in critical steps of the viral life cycle. However, whether HBc could regulate HBV cccDNA transcription remains under debate. In this study, different approaches were used to address this question. In synthesized HBV cccDNA and HBVcircle transfection assays, lack of HBc showed no effect on transcription of HBV RNA as well as HBV surface antigen (HBsAg) production in a hepatoma cell line and primary human hepatocytes. Reconstitution of HBc did not alter the expression of cccDNA-derived HBV markers. Similar results were obtained from an in vivo mouse model harboring cccDNA. Chromatin immunoprecipitation (ChIP) or ChIP sequencing assays revealed transcription regulation of HBc-deficient cccDNA chromatin similar to that of wild-type cccDNA. Furthermore, treatment with capsid assembly modulators (CAMs) dramatically reduced extracellular HBV DNA but could not alter viral RNA and HBsAg. Our results demonstrate that HBc neither affects histone modifications and transcription factor binding of cccDNA nor directly influences cccDNA transcription. Although CAMs could reduce HBc binding to cccDNA, they do not suppress cccDNA transcriptional activity. Thus, therapeutics targeting capsid or HBc should not be expected to sufficiently reduce cccDNA transcription. IMPORTANCE Hepatitis B virus (HBV) core protein (HBc) has emerged as a promising antiviral target. However, whether HBc can regulate HBV covalently closed circular DNA (cccDNA) transcription remains elusive. This study illustrated that HBc has no effect on epigenetic regulation of cccDNA, and it does not participate in cccDNA transcription. Given that HBc is dispensable for cccDNA transcription, novel cccDNA-targeting therapeutics are needed for an HBV cure.


Assuntos
DNA Circular , Hepatite B , Animais , Humanos , Camundongos , Antivirais , Proteínas do Capsídeo/genética , DNA Circular/genética , DNA Viral/genética , Epigênese Genética , Hepatite B/genética , Antígenos de Superfície da Hepatite B , Vírus da Hepatite B/fisiologia , Proteínas do Core Viral/genética , Proteínas do Core Viral/metabolismo , Replicação Viral/genética , Transcrição Gênica
16.
Fish Shellfish Immunol ; 133: 108519, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36608811

RESUMO

The terminal differentiation of B cells into plasma cells is central to the generation of protective, long-lived humoral immune responses. In mammals, interleukin-2 (IL-2) has been shown to play a role in B cell proliferation and differentiation. However, it remains unclear whether fish IL-2 is involved in B cell proliferation and differentiation. To this end, we investigated the regulatory role of IL-2 in B cell proliferation and differentiation in large yellow croaker (Larimichthys crocea). We found that L. crocea IL-2 (LcIL-2) significantly increased IgM+ B cells proliferation both in vivo and in vitro and facilitated IgM+ B cells differentiation into plasma cells. Furthermore, LcIL-2 increased the production of specific antibodies after immunization with the Vibrio alginolyticus subunit vaccine, recombinant dihydrolipoamide dehydrogenase (rDLD); simultaneous administration of LcIL-2 and rDLD prior to challenge with Vibrio parahaemolyticus or V. alginolyticus significantly increased relative percent survival. Mechanistically, LcIL-2 promoted B cell proliferation and regulated B cell differentiation by triggering the JAK-STAT5 signaling pathway. Collectively, our results demonstrated that LcIL-2 improved B cell proliferation and specific antibody production via the conserved JAK-STAT5 signaling pathway in large yellow croaker, providing valuable insights into the mechanisms underlying the IL-2-mediated regulation of the humoral immune response in fish.


Assuntos
Proteínas de Peixes , Interleucina-2 , Perciformes , Animais , Doenças dos Peixes , Imunidade Humoral , Imunoglobulina M/metabolismo , Interleucina-2/genética , Mamíferos/metabolismo , Transdução de Sinais , Fator de Transcrição STAT5
17.
Environ Sci Technol ; 57(50): 21104-21112, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38054477

RESUMO

Today, agricultural irrigation consumes the largest amount of freshwater globally, while humans are threatened by water scarcity. To eliminate the trade-off between hunger and thirst, here, we show off-grid maritime agriculture based on a floating solar-driven agro-desalination wooden dome. In this dome, part of the visible light is transmitted for photosynthesis, and the remaining solar energy drives solar desalination, providing enough water (>4 mm day-1) for irrigation. Based on this water-food synergy, the stages of germination and growth are demonstrated. This technology can, to a large extent, support food security and sustainable agriculture and, in principle, be used to create self-circulation systems at sea to help humans survive weather extremes such as floods and droughts.


Assuntos
Agricultura , Abastecimento de Água , Humanos , Fazendas , Água , Oceanos e Mares
18.
Mol Biol Rep ; 50(12): 10121-10129, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37921979

RESUMO

BACKGROUND: We identified a homologue of IL-21R (LcIL-21R) in large yellow croaker (Larimichthys crocea, Lc). Our investigation focused on understanding the molecular structural features and immune function of LcIL-21R. METHODS: We cloned the LcIL-21R gene from the genome of Larimichthys crocea by RT‒PCR, and the molecular and structural characteristics of LcIL-21R were analyzed by a series of protein analysis tools. We used real-time PCR to investigate the tissue distribution of LcIL-21R, and LcIL-21R gene expression regulation was also measured in head kidney leukocytes under trivalent bacterial vaccine or poly (I:C) stimulation. RESULTS: The open reading frame (ORF) of the LcIL-21R gene is 1629 bp long and encodes a precursor protein of 542 amino acids (aa), with a 23-aa signal peptide and a 519-aa mature peptide containing four putative N-glycosylation sites. LcIL-21R has two fibronectin type III (FNIII)-like domains (D1 and D2), a transmembrane domain, and a cytoplasmic region. A conserved WSXWS motif was also found in the D2 domain. The predicted structure of the extracellular region of LcIL-21R (LcIL-21R-Ex) is highly similar to that of human IL-21R. LcIL-21R was constitutively expressed in all tissues examined, and LcIL-21R mRNA levels were increased in the head kidney and spleen upon inactivated trivalent bacterial vaccine or poly(I:C) stimulation. CONCLUSIONS: Our results suggest that LcIL-21R shares structural and functional properties with IL-21Rs found in other vertebrates, indicating its potential involvement in the IL-21-mediated immune response to pathogenic infections. These findings contribute to our understanding of the evolutionary conservation of IL-21 signaling and its role in the immune system.


Assuntos
Perciformes , Receptores de Interleucina-21 , Animais , Humanos , Receptores de Interleucina-21/genética , Receptores de Interleucina-21/metabolismo , Sequência de Aminoácidos , Regulação da Expressão Gênica , Perciformes/metabolismo , Vacinas Bacterianas , Proteínas de Peixes/metabolismo , Filogenia
19.
BMC Pediatr ; 23(1): 265, 2023 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-37237330

RESUMO

OBJECTIVE: To investigate the prevalence of hypertension in adolescents and children in the Taicang area and analyse related factors to provide a theoretical basis for the prevention and control of hypertension in this region. METHODS: A total of 1,000 students who were visited and surveyed in primary schools in the Taicang area in 2021 were selected for statistical testing using a cluster random sampling method, and a survey was conducted on their dietary habits. dietary habits, such as the consumption of meals that included protein-rich animal products, beans and dairy products, vegetables and fruits, salty foods and fried food, was taken into consideration, along with physical fitness indices, waist-to-height ratio and waist circumference. RESULTS: Of the 1,000 adolescents and children surveyed, 222 were classified into the hypertensive group and 778 into the normotensive group. There were 138 boys (a prevalence rate of 6.3%) and 84 girls (a prevalence rate of 4.1%) in the hypertensive group. The physical fitness indices of the hypertensive group were significantly higher than those of the normotensive group. Concerning dietary structure, the frequency of cereal intake between the two groups was comparable, while the hypertensive group's intake of vegetables, fruits, beans and dairy products was significantly lower than that of the normotensive group. Finally, a logistic multivariate regression analysis of related factors was carried out, and it was concluded that waist-to-height ratio, waist circumference and salty and fried food intake were positively correlated with the prevalence of hypertension. CONCLUSION: The prevalence of hypertension among adolescents and children in the Taicang area is high. Body weight and dietary structure can be used as reference indicators for the prevalence of hypertension in this age group.


Assuntos
Dieta , Hipertensão , Humanos , Criança , Prevalência , Peso Corporal , Verduras , Circunferência da Cintura , Hipertensão/epidemiologia , Hipertensão Essencial , Índice de Massa Corporal
20.
BMC Pediatr ; 23(1): 7, 2023 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-36597051

RESUMO

BACKGROUND: Left-to-right shunt congenital heart disease is more likely to induce recurrent respiratory infections in the patients which exacerbate pulmonary hypertension and thereby impairs cardiac function. It is urgent to explore a non-invasive and accurate diagnostic method that can show the cardiac anatomy and associated malformations in clinical research. OBJECTIVE: To determine the diagnostic value of peripheral mucin domain protein-3 (Tim-3), N-terminal pro-brain natriuretic peptide (NT proBNP), sestrin2 testing in patients with the left-to-right shunt congenital heart disease and heart failure. METHODS: Fifty-two neonates with with left to right shunt congenital heart disease and 30 healthy neonates were enrolled. Blood samples were collected within 24 h of admission from newborns for determining the content of TiM-3, NT proBNP, and Sestrin2. Analyzing the ROC curve provided insight into the diagnostic accuracy. Both a Spearman's rank correlation test and a logistic regression analysis were carried out. RESULTS: TiM-3, NT proBNP, and Sestrin2 levels in peripheral blood were statistically different in the three groups (P < 0.05). There were significant differences in LVEF and LVFS among the three groups (P < 0.05). When used to diagnose heart failure in conjunction with left-to-right shunt congenital heart disease, TiM-3, NT proBNP, and Sestrin2 exhibited sensitivity of 58.3, 58.3, and 83.3%, respectively, and specificity of 85.0, 72.5, and 70.0%. ROC curve analysis showed that the AUCs of Tim-3, NT proBNP, and sestrin2 in predicting the outcome of left-to-right shunted congenital heart disease combined with heart failure were 0.744 (95% CI, 0.580 to 0.908), 0.608 (95% CI, 0.359 to 0.857), respectively 0.744 (95% CI 0.592 to 0.896). CONCLUSION: Tim-3, NT proBNP, and sestrin2 can accurately differentiate heart failure from non-combined heart failure from left-to-right shunt congenital heart disease.


Assuntos
Cardiopatias Congênitas , Insuficiência Cardíaca , Humanos , Recém-Nascido , Receptor Celular 2 do Vírus da Hepatite A , Cardiopatias Congênitas/complicações , Cardiopatias Congênitas/diagnóstico , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/diagnóstico , Peptídeo Natriurético Encefálico , Biomarcadores
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA