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1.
J Virol ; 98(3): e0181523, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38421179

RESUMO

Severe fever with thrombocytopenia syndrome virus (SFTSV) is an emerging tick-borne bunyavirus with high pathogenicity. There has been a gradual increase in the number of reported cases in recent years, with high morbidity and mortality rates. The cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) signaling pathway plays an important role in the innate immune defense activated by viral infection; however, the role of the cGAS-STING signaling pathway during SFTSV infection is still unclear. In this study, we investigated the relationship between SFTSV infection and cGAS-STING signaling. We found that SFTSV infection caused the release of mitochondrial DNA into the cytoplasm and inhibits downstream innate immune signaling pathways by activating the cytoplasmic DNA receptor cGAS. We found that the SFTSV envelope glycoprotein Gn was a potent inhibitor of the cGAS-STING pathway and blocked the nuclear accumulation of interferon regulatory factor 3 and p65 to inhibit downstream innate immune signaling. Gn of SFTSV interacted with STING to inhibit STING dimerization and inhibited K27-ubiquitin modification of STING to disrupt the assembly of the STING-TANK-binding kinase 1 complex and downstream signaling. In addition, Gn was found to be involved in inducing STING degradation, further inhibiting the downstream immune response. In conclusion, this study identified the important role of the glycoprotein Gn in the antiviral innate immune response and revealed a novel mechanism of immune escape for SFTSV. Moreover, this study increases the understanding of the pathogenic mechanism of SFTSV and provides new insights for further treatment of SFTS. IMPORTANCE: Severe fever with thrombocytopenia syndrome virus (SFTSV) is a newly discovered virus associated with severe hemorrhagic fever in humans. However, the role of the cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) signaling pathway during SFTSV infection is still unclear. We found that SFTSV infection inhibits downstream innate immune signaling pathways by activating the cytoplasmic DNA receptor cGAS. In addition, SFTSV Gn blocked the nuclear accumulation of interferon regulatory factor 3 and p65 to inhibit downstream innate immune signaling. Moreover, we determined that Gn of SFTSV inhibited K27-ubiquitin modification of STING to disrupt the assembly of the STING-TANK-binding kinase 1 complex and downstream signaling. We found that the SFTSV envelope glycoprotein Gn is a potent inhibitor of the cGAS-STING pathway. In conclusion, this study highlights the crucial function of the glycoprotein Gn in the antiviral innate immune response and reveals a new method of immune escape of SFTSV.


Assuntos
NF-kappa B , Febre Grave com Síndrome de Trombocitopenia , Humanos , NF-kappa B/metabolismo , Fator Regulador 3 de Interferon/metabolismo , Transdução de Sinais/genética , Imunidade Inata/genética , Nucleotidiltransferases/metabolismo , Interferons/metabolismo , Antivirais , Ubiquitinas/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo
2.
J Virol ; 97(4): e0030223, 2023 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-37039677

RESUMO

Severe fever with thrombocytopenia syndrome virus (SFTSV) is a newly identified phlebovirus associated with severe hemorrhagic fever in humans. Studies have shown that SFTSV nucleoprotein (N) induces BECN1-dependent autophagy to promote viral assembly and release. However, the function of other SFTSV proteins in regulating autophagy has not been reported. In this study, we identify SFTSV NSs, a nonstructural protein that forms viroplasm-like structures in the cytoplasm of infected cells as the virus component mediating SFTSV-induced autophagy. We found that SFTSV NSs-induced autophagy was inclusion body independent, and most phenuivirus NSs had autophagy-inducing effects. Unlike N protein-induced autophagy, SFTSV NSs was key in regulating autophagy by interacting with the host's vimentin in an inclusion body-independent manner. NSs interacted with vimentin and induced vimentin degradation through the K48-linked ubiquitin-proteasome pathway. This negatively regulating Beclin1-vimentin complex formed and promoted autophagy. Furthermore, we identified the NSs-binding domain of vimentin and found that overexpression of wild-type vimentin antagonized the induced effect of NSs on autophagy and inhibited viral replication, suggesting that vimentin is a potential antiviral target. The present study shows a novel mechanism through which SFTSV nonstructural protein activates autophagy, which provides new insights into the role of NSs in SFTSV infection and pathogenesis. IMPORTANCE Severe fever with thrombocytopenia syndrome virus (SFTSV) is a newly emerging tick-borne pathogen that causes multifunctional organ failure and even death in humans. As a housekeeping mechanism for cells to maintain steady state, autophagy plays a dual role in viral infection and the host's immune response. However, the relationship between SFTSV infection and autophagy has not been described in detail yet. Here, we demonstrated that SFTSV infection induced complete autophagic flux and facilitated viral proliferation. We also identified a key mechanism underlying NSs-induced autophagy, in which NSs interacted with vimentin to inhibit the formation of the Beclin1-vimentin complex and induced vimentin degradation through K48-linked ubiquitination modification. These findings may help us understand the new functions and mechanisms of NSs and may aid in the identification of new antiviral targets.


Assuntos
Autofagia , Phlebovirus , Febre Grave com Síndrome de Trombocitopenia , Vimentina , Proteínas não Estruturais Virais , Humanos , Autofagia/genética , Proteína Beclina-1/metabolismo , Phlebovirus/metabolismo , Febre Grave com Síndrome de Trombocitopenia/fisiopatologia , Febre Grave com Síndrome de Trombocitopenia/virologia , Vimentina/genética , Vimentina/metabolismo , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/metabolismo , Replicação Viral/fisiologia , Regulação para Baixo , Domínios Proteicos
3.
Anal Bioanal Chem ; 416(5): 1179-1188, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38148365

RESUMO

A facile and sensitive fluorescent and colorimetric dual-readout assay for detection of acid phosphatase (ACP) was developed via Ce(III) ions-directed aggregation-induced emission (AIE) of glutathione-protected gold nanoclusters (GSH-AuNCs) and oxidase-mimicking activity of Ce(IV) ions. Free Ce(IV) ions exhibited a strong oxidase-mimetic activity, catalytically oxidizing colorless 3,3',5,5'-tetramethylbenzidine (TMB) into its blue product oxTMB in the presence of dissolved O2, thus triggering a remarkable color reaction detected visually. ACP can hydrolyze L-ascorbic acid-2-phosphate (AAP) with the production of ascorbic acid (AA). The AA is able to reduce Ce(IV) ions to Ce(III) ions, thus quenching the oxidase-mimetic activity of Ce(IV) ions. Meanwhile, Ce(III) ions induce AIE of GSH-AuNCs, resulting in the enhancement of the fluorescence signal of GSH-AuNCs. Both the fluorescent and colorimetric dual-mode analysis platforms exhibit a sensitive response to ACP, providing detection limits as low as 0.101 U/L and 0.200 U/L, respectively. Besides, this fabricated dual-mode detection platform holds the potential for analysis of ACP in human serum samples and screening inhibitors for ACP. With good performance and practicability, this study shows promising application in the convenient and reliable determination of ACP activity.


Assuntos
Fosfatase Ácida , Cério , Humanos , Oxirredutases , Colorimetria/métodos , Íons , Limite de Detecção
4.
Macromol Rapid Commun ; 45(8): e2300676, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38232334

RESUMO

Poly(ionic liquid) (PIL)-based porous membranes are extensively investigated as soft polymer actuators. While PILs have shown significant advancements in membrane fabrication and stabilization of metal nanoparticles (MNPs), research on integrating MNPs into porous membranes to achieve actuation behavior under multiple stimuli is limited. Herein, this work presents a new paradigm for designing a porous PIL-polyacrylic acid (PAA) membrane with a distinct MNP gradient via a top-bottom diffusion approach involving a metal salt precursor solution and NaBH4 as a reducing agent. The strong binding sites provided by PILs, combined with the gradient distribution of -COO- groups across the membrane cross-section, play a significant role in controlling the MNPs' gradient distribution. Interestingly, the MNPs within the membrane display excellent catalytic activity in exothermic reactions such as H2O2 decomposition, dissipating uneven heat that quickly permeates the membrane network. This induces asymmetrical swelling of polymer chains, resulting in rapid membrane bending. Furthermore, such MNP-loaded membrane could serve as a portable test paper for visually monitoring H2O2. This advancement paves the way for the development of intricate smart actuation materials and expands their practical applications in various real-life scenarios.


Assuntos
Líquidos Iônicos , Nanopartículas Metálicas , Líquidos Iônicos/química , Nanopartículas Metálicas/química , Porosidade , Polímeros/química , Resinas Acrílicas/química , Membranas Artificiais , Peróxido de Hidrogênio/química , Catálise , Propriedades de Superfície , Tamanho da Partícula
5.
J Virol ; 96(14): e0078822, 2022 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-35862701

RESUMO

Dabie bandavirus (DBV) is an emerging Bandavirus that causes multiorgan failure with a high fatality rate in humans. While many viruses can manipulate the actin cytoskeleton to facilitate viral growth, the regulation pattern of the actin cytoskeleton and the molecular mechanisms involved in DBV entry into the host cells remain unclear. In this study, we demonstrate that expression of nonstructural protein (NSs) or infection with DBV induces actin rearrangement, which presents a point-like distribution, and this destruction is dependent on inclusion bodies (IBs). Further experiments showed that NSs inhibits viral adsorption by destroying the filopodium structure. In addition, NSs also compromised the viral entry by inhibiting clathrin aggregation on the cell surface and capturing clathrin into IBs. Furthermore, NSs induced clathrin light chain B (CLTB) degradation through the K48-linked ubiquitin proteasome pathway, which could negatively regulate clathrin-mediated endocytosis, inhibiting the viral entry. Finally, we confirmed that this NSs-induced antiviral mechanism is broadly applicable to other viruses, such as enterovirus 71 (EV71) and influenza virus, A/PR8/34 (PR8), which use the same clathrin-mediated endocytosis to enter host cells. In conclusion, our study provides new insights into the role of NSs in inhibiting endocytosis and a novel strategy for treating DBV infections. IMPORTANCEDabie bandavirus (DBV), a member of the Phenuiviridae family, is a newly emerging tick-borne pathogen that causes multifunctional organ failure and even death in humans. The actin cytoskeleton is involved in various crucial cellular processes and plays an important role in viral life activities. However, the relationship between DBV infection and the actin cytoskeleton has not been described in detail. Here, we show for the first time the interaction between NSs and actin to induce actin rearrangement, which inhibits the viral adsorption and entry. We also identify a key mechanism underlying NSs-induced entry inhibition in which NSs prevents clathrin aggregation on the cell surface by hijacking clathrin into the inclusion body and induces CLTB degradation through the K48-linked ubiquitination modification. This paper is the first to reveal the antiviral mechanism of NSs and provides a theoretical basis for the search for new antiviral targets.


Assuntos
Actinas , Vírus de RNA , Proteínas não Estruturais Virais , Internalização do Vírus , Citoesqueleto de Actina/metabolismo , Actinas/metabolismo , Clatrina/metabolismo , Endocitose/fisiologia , Humanos , Vírus de RNA/metabolismo , Vírus de RNA/fisiologia , Proteínas não Estruturais Virais/metabolismo
6.
Acc Chem Res ; 55(24): 3675-3687, 2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-36469417

RESUMO

ConspectusDiscovering and constructing molecular functionality platforms for materials chemistry innovation has been a persistent target in the fields of chemistry, materials, and engineering. Around this task, basic scientific questions can be asked, novel functional materials can be synthesized, and efficient system functionality can be established. Poly(ionic liquid)s (PILs) have attracted growing interest far beyond polymer science and are now considered an interdisciplinary crossing point between multiple research areas due to their designable chemical structure, intriguing physicochemical properties, and broad and diverse applications. Recently, we discovered that 1,2,4-triazolium-type PILs show enhanced performance profiles, which are due to stronger and more abundant supramolecular interactions ranging from hydrogen bonding to metal coordination, when compared with structurally similar imidazolium counterparts. This phenomenon in our view can be related to the smart hydrogen atoms (SHAs), that is, any proton that binds to the carbon in the N-heterocyclic cations of 1,2,4-triazolium-type PILs. The replacement of one carbon by an electron-withdrawing nitrogen atom in the broadly studied heterocyclic imidazolium ring will further polarize the C-H bond (especially for C5-H) of the resultant 1,2,4-triazolium cation and establish new chemical tools for materials design. For instance, the H-bond-donating strength of the SHA, as well as its BroÌ·nsted acidity, is increased. Furthermore, polycarbene complexes can be readily formed even in the presence of weak or medium bases, which is by contrast rather challenging for imidazolium-type PILs. The combination of SHAs with the intrinsic features of heterocyclic cation-functionalized PILs (e.g., N-coordination capability and polymeric multibinding effects) enables new phenomena and therefore innovative materials applications.In this Account, recent progress on SHAs is presented. SHA-related applications in several research branches are highlighted together with the corresponding materials design at size scales ranging from nano- to micro- and macroscopic levels. At a nanoscopic level, it is possible to manipulate the interior and outer shapes and surface properties of PIL nanocolloids by adjusting the hydrogen bonds (H-bonds) between SHAs and water. Owing to the interplay of polycarbene structure, N-coordination, and the polymer multidentate binding of 1,2,4-triazolium-type PILs, metal clusters with controllable size at sub-nanometer scale were successfully synthesized and stabilized, which exhibited record-high catalytic performance in H2 generation via methanolysis of ammonia borane. At the microscopic level, SHAs are found to efficiently catalyze single crystal formation of structurally complex organics. Free protons in situ released from the SHAs serve as organocatalysts to activate formation of C-N bonds at room temperature in a series of imine-linked crystalline porous organics, such as organic cages, macrocycles and covalent organic frameworks; meanwhile the concurrent "salting-out" effect of PILs as polymers in solution accelerated the crystallization rate of product molecules by at least 1 order of magnitude. At the macroscopic scale, by finely regulating the supramolecular interactions of SHAs, a series of functional supramolecular porous polyelectrolyte membranes (SPPMs) with switchable pores and gradient cross-sectional structures were manufactured. These membranes demonstrate impressive figures of merit, ranging from chiral separation and proton recognition to switchable optical properties and real-time chemical reaction monitoring. Although the concept of SHAs is in the incipient stage of development, our successful examples of applications portend bright prospects for materials chemistry innovation.

7.
J Virol ; 95(3)2021 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-33148796

RESUMO

Human enterovirus D68 (EV-D68) has received considerable attention recently as a global reemergent pathogen because it causes severe respiratory tract infections and acute flaccid myelitis (AFM). The nonstructural protein 2A protease (2Apro) of EVs, which functions in the cleavage of host proteins, comprises a pivotal part of the viral immune evasion process. However, the pathogenic mechanism of EV-D68 is not fully understood. In this study, we found that EV-D68 inhibited antiviral type I interferon responses by cleaving tumor necrosis factor receptor-associated factor 3 (TRAF3), which is the key factor for type I interferon production. EV-D68 inhibited Sendai virus (SEV)-induced interferon regulatory factor 3 (IRF3) activation and beta interferon (IFN-ß) expression in HeLa and HEK293T cells. Furthermore, we demonstrated that EV-D68 and 2Apro were able to cleave the C-terminal region of TRAF3 in HeLa and HEK293T cells, respectively. A cysteine-to-alanine substitution at amino acid 107 (C107A) in the 2Apro protease resulted in the loss of cleavage activity to TRAF3, and mutation of glycine at amino acid 462 to alanine (G462A) in TRAF3 conferred resistance to 2Apro These results suggest that control of TRAF3 by 2Apro may be a mechanism EV-D68 utilizes to subvert host innate immune responses.IMPORTANCE Human enterovirus 68 (EV-D68) has received considerable attention recently as a global reemergent pathogen because it causes severe respiratory tract infections and acute flaccid myelitis. The nonstructural protein 2A protease (2Apro) of EV, which functions in cleavage of host proteins, comprises an essential part of the viral immune evasion process. However, the pathogenic mechanism of EV-D68 is not fully understood. Here, we show for the first time that EV-D68 inhibited antiviral type I interferon responses by cleaving tumor necrosis factor receptor-associated factor 3 (TRAF3). Furthermore, we identified the key cleavage site in TRAF3. Our study may suggest a new mechanism by which the 2Apro of EV facilitates subversion of host innate immune responses. These findings increase our understanding of EV-D68 infection and may help identify new antiviral targets against EV-D68.


Assuntos
Enterovirus Humano D/enzimologia , Infecções por Enterovirus/imunologia , Interações Hospedeiro-Patógeno/imunologia , Imunidade Inata/imunologia , Peptídeo Hidrolases/metabolismo , Fator 3 Associado a Receptor de TNF/metabolismo , Proteínas Virais/metabolismo , Infecções por Enterovirus/metabolismo , Infecções por Enterovirus/patologia , Infecções por Enterovirus/virologia , Células HEK293 , Células HeLa , Humanos , Interferon Tipo I/metabolismo , Peptídeo Hidrolases/genética , Proteólise , Fator 3 Associado a Receptor de TNF/genética , Proteínas Virais/genética
8.
Cancer Cell Int ; 22(1): 264, 2022 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-35996149

RESUMO

Interaction between tumor cells and tumor microenvironment (TME) is critical to promote tumor progression and metastasis. As the most abundant immune cells in TME, macrophages can be polarized into M2-like tumor-associated macrophages (TAMs) which further promote tumor progression. However, to date, the molecular mechanisms of TAM polarization in TME are still largely unknown. In the present study, we revealed that circular RNA circWWC3 could up-regulate the expression and secretion of IL-4 in breast cancer cells. Enhanced secretion of IL-4 from breast cancer cells could augment the M2-like polarization of macrophages in TME, which further promotes the migration of breast cancer cells. In addition, increased secretion of IL-4 from breast cancer cells could induce the expression PD-L1 in M2 macrophages. Moreover, up-regulated IL-4 also enhanced the expression of PD-L1 in breast cancer cells, which further facilitates breast cancer immune evasion. Though analyzing the expression of circWWC3, IL-4, PD-L1, and CD163 in 140 cases of breast cancer tissues, we found that high expression of circWWC3 was associated with poor overall survival and disease-free survival of breast cancer patients. Breast cancer patients with circWWC3high/PD-L1high breast cancer cells and CD163high macrophages had a poorer overall survival and disease-free survival. Conclusively, circWWC3 might augment breast cancer progression through promoting M2 macrophage polarization and tumor immune escape via regulating the expression and secretion of IL-4. CircWWC3 might be a potential therapeutic target in breast cancer.

9.
Chemistry ; 28(40): e202201199, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35560996

RESUMO

The effective capture of iodine with high volatility and poisonousness is significant for reprocessing the spent nuclear fuel. In this article, we report a hierarchically porous poly(ionic liquid)-organic cage composite membrane (PIL@CC3) possessing a gradient content distribution of CC3 cage crystals throughout the membrane to capture iodine vapor. The introduction of microporous CC3 can significantly enhance the uptake capacity of iodine up to 980 mg g-1 , which is superior to that of a pristine PIL membrane carrying large meso- and macropores (99 mg g-1 ), and CC3 crystalline powder (662 mg g-1 ). Such enhanced performance benefits from the micro-meso-macroporous structure of the PIL@CC3 membrane in which the large meso- and macropores facilitate the mass transfer of iodine molecules from the external environment into the surface of the CC3 crystal, followed by diffusion of iodine molecules from the CC3 surface into the interior and exterior pores of the CC3 crystal. In addition, the asymmetric distribution of CC3 crystals across the PIL@CC3 membrane also displays its advantage in intercepting trace iodine, revealing its great potential for practical application. This study provides an idea for constructing hierarchically porous membrane composites for the removal of toxic vapors.

10.
Cochrane Database Syst Rev ; 5: CD013692, 2022 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-35579383

RESUMO

BACKGROUND: Vertebral artery stenosis (narrowing of the vertebral artery) is an important cause of posterior circulation ischaemic stroke. Medical treatment (MT) e.g. controlling risk-factors and drug treatment, surgery, and endovascular treatment (ET) are the prevailing treatment strategies for symptomatic vertebral artery stenosis. ET consist s of percutaneous transluminal angioplasty (balloon catheter through the skin), with or without stenting. However, optimal management of people with symptomatic vertebral artery stenosis has not yet been established. OBJECTIVES: To assess the safety and efficacy of percutaneous transluminal angioplasty, with or without stenting, combined with MT, compared to MT alone, in people with episodes of cerebral ischaemia due to vertebral artery stenosis. SEARCH METHODS: We searched the Cochrane Stroke Group, MEDLINE, Embase, BIOSIS, and two other indexes in Web of Science, China Biological Medicine Database, Chinese Science and Technique Journals Database, China National Knowledge Infrastructure and Wanfang Data, as well as ClinicalTrials.gov trials register and the World Health Organization (WHO) International Clinical Trials Registry Platform to 23 July 2021. SELECTION CRITERIA: We included all randomised controlled trials (RCTs) that compared ET plus MT with MT alone in treating people aged 18 years or over with symptomatic vertebral artery stenosis. We included all types of ET modalities (e.g. angioplasty alone, balloon-mounted stenting, and angioplasty followed by placement of a self-expanding stent). MT included risk factor control, antiplatelet therapy, lipid-lowering therapy, and individualised management for people with hypertension or diabetes. DATA COLLECTION AND ANALYSIS: Two review authors independently screened potentially eligible studies, extracted data, and assessed trial quality and risk of bias.  We applied the GRADE approach to assess the certainty of evidence. The primary outcomes were 30-day post-randomisation death/stroke (short-term outcome) and fatal/non-fatal stroke after 30 days post-randomisation to completion of follow-up (long-term outcome).  MAIN RESULTS: We included three RCTs with 349 participants with symptomatic vertebral artery stenosis with a mean age of 64.4 years. The included RCTs were at low risk of bias overall. However, all included studies had a high risk of performance bias because blinding of the ET was not feasible. There was no significant difference in 30-day post-randomisation deaths/strokes between ET plus MT and MT alone (risk ratio (RR) 2.33, 95% confidence interval (CI) 0.77 to 7.07; 3 studies, 349 participants; low-certainty evidence). There were no significant differences between ET plus MT and MT alone in fatal/non-fatal strokes in the territory of the treated vertebral artery stenosis after 30 days post-randomisation to completion of follow-up (RR 0.51, 95% CI 0.26 to 1.01; 3 studies, 349 participants; moderate-certainty evidence), ischaemic or haemorrhagic stroke during the entire follow-up period (RR 0.77, 95% CI 0.44 to 1.32; 3 studies, 349 participants; moderate-certainty evidence), death during the entire follow-up period (RR 0.78, 95% CI 0.37 to 1.62; 3 studies, 349 participants; low-certainty evidence), and stroke or transient ischaemic attack (TIA) during the entire follow-up period (RR 0.65, 95% CI 0.39 to 1.06; 2 studies, 234 participants; moderate-certainty evidence). AUTHORS' CONCLUSIONS: This Cochrane Review provides low- to moderate-certainty evidence indicating that there are no significant differences in either short- or long-term risks of stroke, death, or TIA between people with symptomatic vertebral artery stenosis treated with ET plus MT and those treated with MT alone.


Assuntos
Ataque Isquêmico Transitório , Acidente Vascular Cerebral , Insuficiência Vertebrobasilar , Angioplastia/efeitos adversos , Angioplastia/métodos , Humanos , Ataque Isquêmico Transitório/etiologia , Pessoa de Meia-Idade , Stents/efeitos adversos , Acidente Vascular Cerebral/complicações , Insuficiência Vertebrobasilar/complicações , Insuficiência Vertebrobasilar/terapia
11.
J Virol ; 94(7)2020 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-31941779

RESUMO

Stress granules (SGs) are formed in the cytoplasm under environmental stress, including viral infection. Human enterovirus D68 (EV-D68) is a highly pathogenic virus which can cause serious respiratory and neurological diseases. At present, there is no effective drug or vaccine against EV-D68 infection, and the relationship between EV-D68 infection and SGs is poorly understood. This study revealed the biological function of SGs in EV-D68 infection. Our results suggest that EV-D68 infection induced the accumulation of SG marker proteins Ras GTPase-activated protein-binding protein 1 (G3BP1), T cell intracellular antigen 1 (TIA1), and human antigen R (HUR) in the cytoplasm of infected host cells during early infection but inhibited their accumulation during the late stage. Simultaneously, we revealed that EV-D68 infection induces HUR, TIA1, and G3BP1 colocalization, which marks the formation of typical SGs dependent on protein kinase R (PKR) and eIF2α phosphorylation. In addition, we found that TIA1, HUR, and G3BP1 were capable of targeting the 3' untranslated regions (UTRs) of EV-D68 RNA to inhibit viral replication. However, the formation of SGs in response to arsenite (Ars) gradually decreased as the infection progressed, and G3BP1 was cleaved in the late stage as a strategy to antagonize SGs. Our findings have important implications in understanding the mechanism of interaction between EV-D68 and the host while providing a potential target for the development of antiviral drugs.IMPORTANCE EV-D68 is a serious threat to human health, and there are currently no effective treatments or vaccines. SGs play an important role in cellular innate immunity as a target with antiviral effects. This manuscript describes the formation of SGs induced by EV-D68 early infection but inhibited during the late stage of infection. Moreover, TIA1, HUR, and G3BP1 can chelate a specific site of the 3' UTR of EV-D68 to inhibit viral replication, and this interaction is sequence and complex dependent. However, this inhibition can be antagonized by overexpression of the minireplicon. These findings increase our understanding of EV-D68 infection and may help identify new antiviral targets that can inhibit viral replication and limit the pathogenesis of EV-D68.


Assuntos
Regiões 3' não Traduzidas , Grânulos Citoplasmáticos/virologia , Enterovirus Humano D/genética , Replicação Viral , Células A549 , Linhagem Celular Tumoral , Citoplasma/metabolismo , Grânulos Citoplasmáticos/metabolismo , DNA Helicases/metabolismo , Proteína Semelhante a ELAV 1/metabolismo , Enterovirus Humano D/fisiologia , Células HEK293 , Células HeLa , Humanos , Fosforilação , Proteínas de Ligação a Poli-ADP-Ribose/metabolismo , RNA Helicases/metabolismo , Proteínas com Motivo de Reconhecimento de RNA/metabolismo , RNA Interferente Pequeno/metabolismo , RNA Viral/metabolismo , Antígeno-1 Intracelular de Células T/metabolismo
12.
J Virol ; 94(6)2020 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-31852787

RESUMO

Severe fever with thrombocytopenia syndrome virus (SFTSV) is a newly identified phlebovirus associated with severe hemorrhagic fever in humans. While many viruses subvert the host cell cycle to promote viral growth, it is unknown whether this is a strategy employed by SFTSV. In this study, we investigated how SFTSV manipulates the cell cycle and the effect of the host cell cycle on SFTSV replication. Our results suggest that cells arrest at the G2/M transition following infection with SFTSV. The accumulation of cells at the G2/M transition did not affect virus adsorption and entry but did facilitate viral replication. In addition, we found that SFTSV NSs, a nonstructural protein that forms viroplasm-like structures in the cytoplasm of infected cells and promotes virulence by modulating the interferon response, induces a large number of cells to arrest at the G2/M transition by interacting with CDK1. The interaction between NSs and CDK1, which is inclusion body dependent, inhibits formation and nuclear import of the cyclin B1-CDK1 complex, thereby leading to cell cycle arrest. Expression of a CDK1 loss-of-function mutant reversed the inhibitive effect of NSs on the cell cycle, suggesting that this protein is a potential antiviral target. Our study provides new insight into the role of a specific viral protein in SFTSV replication, indicating that NSs induces G2/M arrest of SFTSV-infected cells, which promotes viral replication.IMPORTANCE Severe fever with thrombocytopenia syndrome virus (SFTSV) is a tick-borne pathogen that causes severe hemorrhagic fever. Although SFTSV poses a serious threat to public health and was recently isolated, its pathogenesis remains unclear. In particular, the relationship between SFTSV infection and the host cell cycle has not been described. Here, we show for the first time that both asynchronized and synchronized SFTSV-susceptible cells arrest at the G2/M checkpoint following SFTSV infection and that the accumulation of cells at this checkpoint facilitates viral replication. We also identify a key mechanism underlying SFTSV-induced G2/M arrest, in which SFTSV NSs interacts with CDK1 to inhibit formation and nuclear import of the cyclin B1-CDK1 complex, thus preventing it from regulating cell cycle progression. Our study highlights the key role that NSs plays in SFTSV-induced G2/M arrest.


Assuntos
Infecções por Bunyaviridae/metabolismo , Proteína Quinase CDC2/metabolismo , Pontos de Checagem da Fase G2 do Ciclo Celular , Phlebovirus/fisiologia , Proteínas não Estruturais Virais/metabolismo , Replicação Viral , Infecções por Bunyaviridae/genética , Infecções por Bunyaviridae/patologia , Proteína Quinase CDC2/genética , Ciclina B1/genética , Ciclina B1/metabolismo , Células HEK293 , Células HeLa , Células Hep G2 , Humanos , Proteínas não Estruturais Virais/genética
13.
J Cell Biochem ; 121(2): 1039-1049, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31490018

RESUMO

Autophagy is a kind of intracellular degradation pathway which could be regulated by many noncoding RNAs. ciRS-7, also called CDR1as, is a circular RNA that is relatively well studied at present. In our recent study, we have found that the expression of ciRS-7 is abnormally increased in the esophageal squamous cell carcinoma (ESCC), and may function as an oncogene to accelerate ESCC progression through sponging miR-876-5p. Meanwhile, another study showed that ciRS-7 is highly expressed in the triple-negative breast cancer (TNBC) and may function as a competing endogenous RNA of miR-1299 to maintain the high migration and invasive capacity of TNBC cells. Of interest, in the present work, we observed that ciRS-7 could inhibit starvation or rapamycin-induced autophagy of ESCC cells and miR-1299 promotes starvation or rapamycin-induced autophagy of ESCC cells. Mechanically, miR-1299 could directly bind to the 3'-untranslated region of epidermal growth factor receptor (EGFR) and then affects its downstream Akt-mTOR pathway in ESCC cells. Consistent with our past findings, ciRS-7 could also sponge miR-1299 in ESCC cells. Taken together, this study has shed light on that circular RNA ciRS-7 inhibits autophagy of ESCC cells by functioning as miR-1299 sponge to target EGFR signaling.


Assuntos
Autofagia , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas do Esôfago/patologia , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , RNA Circular/genética , Apoptose , Biomarcadores Tumorais/genética , Movimento Celular , Proliferação de Células , Receptores ErbB/genética , Receptores ErbB/metabolismo , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/genética , Carcinoma de Células Escamosas do Esôfago/metabolismo , Humanos , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Células Tumorais Cultivadas
14.
Virus Genes ; 54(4): 484-492, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29777445

RESUMO

Human enterovirus D68 (EV-D68) is a highly contagious virus, which causes respiratory tract infections. However, no effective vaccines are currently available for controlling EV-D68 infection. Here, we developed a reverse genetics system to recover EV-D68 minireplicons and infectious EV-D68 from transfected plasmids using the RNA polymerase I (Pol I) promoter. The EV-D68 minireplicons contained the luciferase reporter gene, which flanked by the non-coding regions of the EV-D68 RNA. The luciferase signals could be detected in cells after transfection and Pol I promoter-mediated luciferase signal was significantly stronger than that mediated by the T7 promoter. Furthermore, recombinant viruses were generated by transfecting plasmids that contained the genomic RNA segments of EV-D68, under the control of Pol I promoter into 293T cells or RD cells. On plaque morphology and growth kinetics, the rescued virus and parental virus were indistinguishable. In addition, we showed that the G394C mutation disrupts the viral 5'-UTR structure and suppresses the viral cap-independent translation. This reverse genetics system for EV-D68 recovery can greatly facilitate research into EV-D68 biology. Moreover, this system could accelerate the development of EV-D68 vaccines and anti-EV-D68 drugs.


Assuntos
Enterovirus Humano D/genética , Infecções por Enterovirus/virologia , RNA Polimerase I/genética , Genética Reversa , Linhagem Celular , DNA Complementar , Ordem dos Genes , Engenharia Genética , Humanos , Mutação , Conformação de Ácido Nucleico , Plasmídeos/genética , Regiões Promotoras Genéticas , RNA Polimerase I/metabolismo , RNA Viral , Infecções Respiratórias/virologia , Genética Reversa/métodos , Ensaio de Placa Viral , Replicação Viral
15.
Nat Commun ; 15(1): 2478, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38509092

RESUMO

Biological cell membrane featuring smart mass-transport channels and sub-10 nm thickness was viewed as the benchmark inspiring the design of separation membranes; however, constructing highly connective and adaptive pore channels over large-area membranes less than 10 nm in thickness is still a huge challenge. Here, we report the design and fabrication of sub-8 nm networked cage nanofilms that comprise of tunable, responsive organic cage-based water channels via a free-interface-confined self-assembly and crosslinking strategy. These cage-bearing composite membranes display outstanding water permeability at the 10-5 cm2 s-1 scale, which is 1-2 orders of magnitude higher than that of traditional polymeric membranes. Furthermore, the channel microenvironments including hydrophilicity and steric hindrance can be manipulated by a simple anion exchange strategy. In particular, through ionically associating light-responsive anions to cage windows, such 'smart' membrane can even perform graded molecular sieving. The emergence of these networked cage-nanofilms provides an avenue for developing bio-inspired ultrathin membranes toward smart separation.

16.
Mult Scler Relat Disord ; 84: 105423, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38359691

RESUMO

PURPOSE: To assess the retinal structural and microvascular change in aquaporin-4 antibody (AQP4) positive neuromyelitis optica spectrum disorder (NMOSD) patients and the correlation with clinical features. METHODS: A cross-sectional study was performed with optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA) to measure retinal structure and microvascular parameters in AQP4 positive NMOSD patients. RESULTS: Sixty-two NMOSD patients (44 eyes with ON, NMOSD+ON; 77 eyes without ON, NMOSD-ON) and 62 healthy controls (HC, 124 eyes) were included. BCVA was worse in NMOSD patients compared to HC (p<0.001). Peripapillary retinal nerve fiber layer (pRNFL, p<0.001) and ganglion cell complex (GCC, p<0.001) was thinner in NMOSD+ON eyes compared to NMOSD-ON eyes and HC. Compared to HC, pRNFL (p = 0.002) and GCC (p = 0.001) was thinner in NMOSD-ON eyes. The vessel density (VD) in superficial capillary plexus (SCP, NMOSD+ON vs HC p<0.001, NMOSD-ON vs HC p = 0.002) and radial peripapillary capillary (RPC, NMOSD+ON vs HC p<0.001, NMOSD-ON vs HC p = 0.001) were also lower in NMOSD patients than HC independent of the history of ON. ON frequency and BCVA were correlated with the thickness of pRNFL and GCC, and VD in SCP and RPC (all p<0.001). EDSS was correlated with thickness of GCC (p = 0.008), and VD in SCP (p = 0.013), DCP (p<0.001) and RPC (p = 0.009). CONCLUSIONS: Subclinical degradation of retinal structure and microvasculature was found in NMOSD patients before the occurrence of ON, and was correlated with clinical disability. Retinal parameter might be a tool to estimate the disease progression and investigate the pathogenesis of NMOSD.


Assuntos
Aquaporinas , Neuromielite Óptica , Neurite Óptica , Humanos , Neuromielite Óptica/complicações , Neuromielite Óptica/diagnóstico por imagem , Tomografia de Coerência Óptica , Estudos Transversais , Angiografia/efeitos adversos , Autoanticorpos/metabolismo , Aquaporina 4
17.
Small Methods ; : e2301468, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38295090

RESUMO

The exploration of a facile approach to create structurally versatile substances carrying air-stable radicals is highly desired, but still a huge challenge in chemistry and materials science. Herein, a non-contact method to generate air-stable radicals by exposing pyridine/imidazole ring-bearing substances to volatile cyanuric chloride vapor, harnessed as a chemical fuel is reported. This remarkable feat is accomplished through a nucleophilic substitution reaction, wherein an intrinsic electron transfer event transpires spontaneously, originating from the chloride anion (Cl- ) to the cationic nitrogen (N+ ) atom, ultimately giving rise to pyridinium/imidazolium radicals. Impressively, the generated radicals exhibit noteworthy stability in the air over one month owing to the delocalization of the unpaired electron through the extended and highly fused π-conjugated pyridinium/imidazolium-triazine unit. Such an approach is universal to diverse substances, including organic molecules, metal-organic complexes, hydrogels, polymers, and organic cage materials. Capitalizing on this versatile technique, surface radical functionalization can be readily achieved across diverse substrates. Moreover, the generated radical species showcase a myriad of high-performance applications, including mimicking natural peroxidase to accelerate oxidation reactions and achieving high-efficiency near-infrared photothermal conversion and photothermal bacterial inhibition.

18.
Transl Vis Sci Technol ; 13(7): 20, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-39078643

RESUMO

Purpose: To examine the effects of serum growth hormone (GH) and insulin-like growth factor-1 (IGF-1) on choroidal structures with different blood glucose levels in patients with diabetes mellitus (DM) with acromegaly without diabetic retinopathy. Methods: Eighty-eight eyes of 44 patients with acromegaly were divided into a nondiabetic group (23 patients, 46 eyes) and a diabetic group (21 patients, 42 eyes). Forty-four age- and sex-matched healthy controls and 21 patients with type 2 DM without diabetic retinopathy were also included. Linear regression models with a simple slope analysis were used to identify the correlation and interaction between endocrine parameters and choroidal thickness (ChT), total choroidal area (TCA), luminal area (LA), stromal area (SA), and choroidal vascular index (CVI). Results: Our study revealed significant increases in the ChT, LA, SA, and TCA in patients with acromegaly compared with healthy controls, with no difference in the CVI. Comparatively, patients with DM with acromegaly had greater ChT than matched patients with type 2 DM, with no significant differences in other choroidal parameters. The enhancement of SA, LA and TCA caused by an acromegalic status disappeared in patients with diabetic status, whereas ChT and CVI were not affected by the interaction. In the diabetic acromegaly, higher IGF-1 (P = 0.006) and GH levels (P = 0.049), longer DM duration (P = 0.007), lower blood glucose (P = 0.001), and the interaction between GH and blood glucose were associated independently with thicker ChT. Higher GH levels (P = 0.016, 0.004 and 0.007), longer DM duration (P = 0.022, 0.013 and 0.013), lower blood glucose (P = 0.034, 0.011 and 0.01), and the interaction of IGF-1 and blood glucose were associated independently with larger SA, LA, and TCA. As blood glucose levels increased, the positive correlation between serum GH level and ChT diminished, and became insignificant when blood glucose was more than 7.35 mM/L. The associations between serum IGF-1 levels and LA, SA, and TCA became increasingly negative, with LA, becoming significantly and negatively associated to the GH levels only when blood glucose levels were more than 8.59 mM/L. Conclusions: Acromegaly-related choroidal enhancements diminish in the presence of DM. In diabetic acromegaly, blood glucose levels are linked negatively with changes in choroidal metrics and their association with GH and IGF-1. Translational Relevance: We revealed the potential beneficial impacts of IGF-1 and GH on structural measures of the choroid in patients with DM at relatively well-controlled blood glucose level, which could provide a potential treatment target for diabetic retinopathy.


Assuntos
Acromegalia , Glicemia , Corioide , Diabetes Mellitus Tipo 2 , Retinopatia Diabética , Fator de Crescimento Insulin-Like I , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Fator de Crescimento Insulin-Like I/análise , Acromegalia/sangue , Acromegalia/complicações , Feminino , Masculino , Pessoa de Meia-Idade , Corioide/patologia , Glicemia/análise , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Retinopatia Diabética/sangue , Adulto , Idoso , Tomografia de Coerência Óptica , Hormônio do Crescimento Humano/sangue , Estudos de Casos e Controles
19.
Breast ; 76: 103762, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38924994

RESUMO

BACKGROUND: Male breast cancer (MBC) is a rare disease. Although several large-scale studies have investigated MBC patients in other countries, the features of MBC patients in China have not been fully explored. This study aims to explore the features of Chinese MBC patients comprehensively. METHODS: We retrospectively collected data of MBC patients from 36 centers in China. Overall survival (OS) was evaluated by the Kaplan-Meier method, log-rank test, and Cox regression analyses. Multivariate Cox analyses were used to identify independent prognostic factors of the patients. RESULTS: In total, 1119 patients were included. The mean age at diagnosis was 60.9 years, and a significant extension over time was observed (P < 0.001). The majority of the patients (89.1 %) received mastectomy. Sentinel lymph node biopsy was performed in 7.8 % of the patients diagnosed in 2009 or earlier, and this percentage increased significantly to 38.8 % in 2020 or later (P < 0.001). The five-year OS rate for the population was 85.5 % [95 % confidence interval (CI), 82.8 %-88.4 %]. Multivariate Cox analysis identified taxane-based [T-based, hazard ratio (HR) = 0.32, 95 % CI, 0.13 to 0.78, P = 0.012] and anthracycline plus taxane-based (A + T-based, HR = 0.47, 95 % CI, 0.23 to 0.96, P = 0.037) regimens as independent protective factors for OS. However, the anthracycline-based regimen showed no significance in outcome (P = 0.175). CONCLUSION: As the most extensive MBC study in China, we described the characteristics, treatment and prognosis of Chinese MBC population comprehensively. T-based and A + T-based regimens were protective factors for OS in these patients. More research is required for this population.


Assuntos
Neoplasias da Mama Masculina , Mastectomia , Biópsia de Linfonodo Sentinela , Humanos , Neoplasias da Mama Masculina/patologia , Neoplasias da Mama Masculina/mortalidade , Neoplasias da Mama Masculina/terapia , Neoplasias da Mama Masculina/epidemiologia , Masculino , Pessoa de Meia-Idade , China/epidemiologia , Estudos Retrospectivos , Mastectomia/estatística & dados numéricos , Idoso , Biópsia de Linfonodo Sentinela/estatística & dados numéricos , Adulto , Prognóstico , Modelos de Riscos Proporcionais , Estimativa de Kaplan-Meier , Taxoides/uso terapêutico , Taxa de Sobrevida , Hidrocarbonetos Aromáticos com Pontes/uso terapêutico , Antraciclinas/uso terapêutico , Idoso de 80 Anos ou mais
20.
Front Med (Lausanne) ; 10: 1232814, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37502362

RESUMO

Background: Hepatocellular carcinoma (HCC) represents a complex ailment characterized by an unfavorable prognosis in advanced stages. The involvement of immune cells in HCC progression is of significant importance. Moreover, metastasis poses a substantial impediment to enhanced prognostication for HCC patients, with anoikis playing an indispensable role in facilitating the distant metastasis of tumor cells. Nevertheless, limited investigations have been conducted regarding the utilization of anoikis factors for predicting HCC prognosis and assessing immune infiltration. This present study aims to identify hepatocellular carcinoma-associated anoikis-related genes (ANRGs), establish a robust prognostic model for HCC, and delineate distinct immune characteristics based on the anoikis signature. Cell migration and cytotoxicity experiments were performed to validate the accuracy of the ANRGs model. Methods: Consensus clustering based on ANRGs was employed in this investigation to categorize HCC samples obtained from both TCGA and Gene Expression Omnibus (GEO) cohorts. To assess the differentially expressed genes, Cox regression analysis was conducted, and subsequently, prognostic gene signatures were constructed using LASSO-Cox methodology. External validation was performed at the International Cancer Genome Conference. The tumor microenvironment (TME) was characterized utilizing ESTIMATE and CIBERSORT algorithms, while machine learning techniques facilitated the identification of potential target drugs. The wound healing assay and CCK-8 assay were employed to evaluate the migratory capacity and drug sensitivity of HCC cell lines, respectively. Results: Utilizing the TCGA-LIHC dataset, we devised a nomogram integrating a ten-gene signature with diverse clinicopathological features. Furthermore, the discriminative potential and clinical utility of the ten-gene signature and nomogram were substantiated through ROC analysis and DCA. Subsequently, we devised a prognostic framework leveraging gene expression data from distinct risk cohorts to predict the drug responsiveness of HCC subtypes. Conclusion: In this study, we have established a promising HCC prognostic ANRGs model, which can serve as a valuable tool for clinicians in selecting targeted therapeutic drugs, thereby improving overall patient survival rates. Additionally, this model has also revealed a strong connection between anoikis and immune cells, providing a potential avenue for elucidating the mechanisms underlying immune cell infiltration regulated by anoikis.

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