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1.
Am J Transl Res ; 16(6): 2379-2388, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39006262

RESUMO

OBJECTIVE: This study aimed to examine the effects of combined rehabilitation and rivastigmine treatment on patients with Parkinson's disease (PD). METHODS: Gait parameters were assessed using the Gibbon Gait Analyzer in fifteen patients. Baseline gait data and cognitive assessments were collected. Each patient underwent external counterpulsation therapy, transcranial magnetic stimulation therapy, and exercise therapy for one hour per day, five days a week for three weeks. Post-intervention, gait and cognitive data were re-evaluated. Alongside their standard PD medications, all participants were administered rivastigmine throughout the study period. RESULTS: The intervention significantly enhanced motor function in the single-task test, evidenced by marked improvements in gait metrics such as stride width and walking speed, and a substantial reduction in fall risk. Cognitive function, assessed by mini-mental state examination and Montreal cognitive assessment, showed an improvement trend after the three-week intervention. Improvements in dual-task walking function were observed, although these changes did not reach statistical significance. CONCLUSION: Multimodal exercise training combined with rivastigmine treatment significantly improves certain gait parameters in the single-task test, enhances balance, and reduces the risk of falling in patients with PD. Cognitive function also demonstrated improvement.

2.
Virology ; 597: 110147, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38905921

RESUMO

The glycoprotein GP64 of alphabaculovirus is crucial for viral entry and fusion. Here, we investigated the N-glycosylation patterns of Bombyx mori nucleopolyhedrovirus (BmNPV) GP64 and its signal peptide (SP) cleaved form, SPΔnGP64, along with their impacts on viral infectivity and fusogenicity. Through deglycosylation assays, we confirmed N-glycosylation of BmNPV GP64 on multiple sites. Mutational analysis targeting predicted N-glycosylation sites revealed diverse effects on viral infectivity and cell fusion. Particularly noteworthy were mutations at sites 175, which resulted in complete loss of infectivity and fusion capacity. Furthermore, LC-MS/MS analysis uncovered unexpected non-classical N-glycosylation sites, including N252, N302, N367, and N471, with only N302 and N471 identified in SPΔnGP64. Subsequent investigation highlighted the critical roles of these residues in BmNPV amplification and fusion, underscoring the essentiality of N367 glycosylation for GP64 fusogenicity. Our findings provide valuable insights into the non-classical glycosylation landscape of BmNPV GP64 and its functional significance in viral biology.


Assuntos
Bombyx , Nucleopoliedrovírus , Internalização do Vírus , Nucleopoliedrovírus/genética , Nucleopoliedrovírus/metabolismo , Nucleopoliedrovírus/fisiologia , Glicosilação , Animais , Bombyx/virologia , Bombyx/metabolismo , Proteínas do Envelope Viral/metabolismo , Proteínas do Envelope Viral/genética , Glicoproteínas/metabolismo , Glicoproteínas/genética , Sinais Direcionadores de Proteínas , Espectrometria de Massas em Tandem , Mutação
3.
J Virol Methods ; 327: 114933, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38582377

RESUMO

Baculovirus has been widely used for foreign protein expression in biomedical studies, and budded virus (BV) surface display has developed into an important research tool for heterogenous membrane protein studies. The basic strategy of surface display is to construct a recombinant virus where the target gene is fused with a complete or partial gp64 gene. In this study, we further investigate and develop this BV surface displaying strategy. We constructed stable insect cell lines to express the target protein flanking with different regions of signal peptide (SP) and GP64 transmembrane domain (TMD). Subsequently, recombinant BmNPV was used to infect the cell, and the integration of heterogeneous protein into BV was detected. The results indicated that deletion of the n-region of SP (SPΔn) decreased the incorporation rate more than that of the full-length SP. However, the incorporation rate of the protein fused with h and c-region deletion of SP (SPΔh-c) was significantly enhanced by 35-40 times compare to full-length SP. Moreover, the foreign protein without SP and TMD failed to display on the BV, while the integration of foreign proteins with GP64 TMD fusion at the c-terminal was significantly enhanced by 12-26 times compared to the control. Thus, these new strategies developed the BV surface display system further.


Assuntos
Nucleopoliedrovírus , Vírion , Animais , Nucleopoliedrovírus/genética , Nucleopoliedrovírus/metabolismo , Linhagem Celular , Vírion/genética , Vírion/metabolismo , Bombyx/virologia , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/metabolismo , Sinais Direcionadores de Proteínas/genética , Domínios Proteicos , Células Sf9 , Montagem de Vírus
4.
Heliyon ; 10(3): e24967, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38322910

RESUMO

Objectives: Postoperative delirium (POD) is considered to be a common complication of spine surgery. Although many studies have reported the risk factors associated with POD, the results remain unclear. Therefore, we performed a meta-analysis to identify risk factors for POD among patients following spinal surgery. Methods: We systematically searched the PubMed, Embase and the Cochrane Library for relevant articles published from 2006 to February 1, 2023 that reported risk factors associated with the incidence of POD among patients undergoing spinal surgery. The Meta-Analysis of Observational Studies in Epidemiology (MOOSE) guidelines were followed, and random effects models were used to estimate pooled odds ratio (OR) estimates with 95 % confidence intervals (CIs) for each factor. The evidence from observational studies was classified according to Egger's P value, total sample size, and heterogeneity between studies. Results: Of 11,329 citations screened, 50 cohort studies involving 1,182,719 participants met the inclusion criteria. High-quality evidence indicated that POD was associated with hypertension, diabetes mellitus, cardiovascular disease, pulmonary disease, older age (>65 years), patients experiencing substance use disorder (take drug ≥1 month), cerebrovascular disease, kidney disease, neurological disorder, parkinsonism, cervical surgery, surgical site infection, postoperative fever, postoperative urinary tract infection, and admission to the intensive care unit (ICU). Moderate-quality evidence indicated that POD was associated with depression, American Society of Anesthesiologists (ASA) fitness grade (>II), blood transfusion, abnormal potassium, electrolyte disorder, length of stay, inability to ambulate and intravenous fluid volume. Conclusions: Conspicuous risk factors for POD were mainly patient- and surgery-related. These findings help clinicians identify high-risk patients with POD following spinal surgery and recognize the importance of early intervention.

5.
Gene ; 881: 147626, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37423399

RESUMO

Diapause of the silkworm (Bombyx mori) is an important ecological adaptation strategy regulated by multiple signaling pathways. As an evolutionarily conserved signaling pathway, the insulin/IGF signaling (IIS) pathway is essential in regulating lifespan, energy accumulation, and stress resistance in diapause insects. However, the regulatory mechanism of IIS on diapause in B. mori is still not fully understood. To investigate the role of the IIS pathway in regulating diapause, we first analyzed the transcription levels of the insulin receptor (BmINR) and its downstream gene adenylate cyclase 6 (BmAC6). The diapause-terminated eggs of a bivoltine strain QiuFeng (V2-QF) were incubated at 25 °C in natural room light for preparing diapause egg producers (DEPs) and at 17 °C in total darkness for preparing non-diapause egg producers (NDEPs), respectively. Then we investigated the effects of BmINR and BmAC6 on diapause phenotype and expression of diapause-related genes by RNA interference (RNAi) and overexpression techniques. The results showed that the mRNA expression levels of BmINR and BmAC6 in the head and ovary of NDEPs were higher than those in DEPs during the early and middle pupal stages. Furthermore, when BmINR was knocked down in the NDEPs, approximately 14.43% of eggs were in light red color and subsequently changed into gray-purple color after 48 h post-oviposition, then stayed in a diapause state. On the other hand, overexpression of BmINR or BmAC6 via recombinant baculoviruses did not cause any obvious phenotypic alterations in NDEPs, but it upregulated the expression of genes related to carbohydrate metabolism, which provides energy for embryonic growth and development. Therefore, it can be concluded that BmINR and BmAC6 genes regulate embryonic diapause in bivoltine B. mori.


Assuntos
Bombyx , Animais , Feminino , Insulina/metabolismo , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Transdução de Sinais , Pupa/genética , Pupa/metabolismo , Óvulo/metabolismo
6.
Int J Surg ; 109(10): 3147-3158, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37318854

RESUMO

OBJECTIVE: The authors conducted this meta-analysis to identify risk factors for spinal epidural haematoma (SEH) among patients following spinal surgery. METHODS: The authors systematically searched Pub: Med, Embase, and the Cochrane Library for articles that reported risk factors associated with the development of SEH in patients undergoing spinal surgery from inception to 2 July 2022. The pooled odds ratio (OR) was estimated using a random-effects model for each investigated factor. The evidence of observational studies was classified as high quality (Class I), moderate quality (Class II or III) and low quality (Class IV) based on sample size, Egger's P value and between-study heterogeneity. In addition, subgroup analyses stratified by study baseline characteristics and leave-one-out sensitivity analyses were performed to explore the potential sources of heterogeneity and the stability of the results. RESULTS: Of 21 791 articles screened, 29 unique cohort studies comprising 150 252 patients were included in the data synthesis. Studies with high-quality evidence showed that older patients (≥60 years) (OR, 1.35; 95% CI, 1.03-1.77) were at higher risk for SEH. Studies with moderate-quality evidence suggested that patients with a BMI greater than or equal to 25 kg/m² (OR, 1.39; 95% CI, 1.10-1.76), hypertension (OR, 1.67; 95% CI, 1.28-2.17), and diabetes (OR, 1.25; 95% CI, 1.01-1.55) and those undergoing revision surgery (OR, 1.92; 95% CI, 1.15-3.25) and multilevel procedures (OR, 5.20; 95% CI, 2.89-9.37) were at higher risk for SEH. Meta-analysis revealed no association between tobacco use, operative time, anticoagulant use or American Society of Anesthesiologists (ASA) classification and SEH. CONCLUSIONS: Obvious risk factors for SEH include four patient-related risk factors, including older age, obesity, hypertension and diabetes, and two surgery-related risk factors, including revision surgery and multilevel procedures. These findings, however, must be interpreted with caution because most of these risk factors had small effect sizes. Nonetheless, they may help clinicians identify high-risk patients to improve prognosis.


Assuntos
Diabetes Mellitus , Hematoma Epidural Espinal , Hipertensão , Humanos , Estudos de Coortes , Hematoma Epidural Espinal/epidemiologia , Hematoma Epidural Espinal/etiologia , Hipertensão/complicações , Fatores de Risco
7.
Environ Geochem Health ; 45(7): 5093-5107, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37069329

RESUMO

Several studies have assessed the influence of several often-ignored environmental factors on low back pain (LBP), but the effects of environmental polycyclic aromatic hydrocarbon (PAH) exposure on LBP are unclear. During the 2001-2004 cycle of the National Health and Nutrition Examination Survey (NHANES), our study was given to a representative sample of US participants older than 20 (N = 2743). Environmental PAH exposure was calculated using urinary PAH metabolite concentrations. Weighted logistic regression was performed to assess the connection between PAH levels and LBP, with mediation analysis utilised to explore the underlying mechanism. Levels of 1-hydroxynaphthalene (1-OHNa), 2-hydroxynaphthalene (2-OHNa) and total PAHs had a statistically significant positive association with LBP. The odds ratios per 1-unit increase for log-transformed levels of urinary 1-OHNa, 2-OHNa, and total PAHs with LBP were 1.01 (95% CI 1.02-1.19), 1.19 (95% CI 1.04-1.36) and 1.16 (95% CI 1.03-1.32), respectively. The results revealed a strong dose-response association between 1-OHNa, 2-OHNa, total PAHs, and LBP risk. Subgroup analysis indicated that 2&3-OHPh may increase the risk of LBP in the lower family income subgroup. Gamma-glutamyl transaminase (GGT), known as a biomarker of oxidative stress, was strongly related to PAHs. The relationship between total PAHs and LBP was mediated in part by GGT. Our study demonstrates associations between environmental PAH exposure and LBP that need more research to determine the precise effects of various PAH compounds on LBP.


Assuntos
Dor Lombar , Hidrocarbonetos Policíclicos Aromáticos , Humanos , Hidrocarbonetos Policíclicos Aromáticos/análise , Inquéritos Nutricionais , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Biomarcadores/urina
8.
J Virol ; 97(3): e0004123, 2023 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-36916914

RESUMO

Baculovirus budded virus (BV) acquires its envelope and viral membrane fusion proteins from the plasma membrane (PM) of the host cell during the budding process. However, this classical BV egress pathway has been questioned because an intracellularly localized membrane fusion protein, SPΔnGP64 (glycoprotein 64 [GP64] lacking the signal peptide [SP] n region), was assembled into the envelope to generate infective BVs in our recent studies. Here, we identify an additional pathway for Bombyx mori nucleopolyhedrovirus (BmNPV) BV assembly and release that differs, in part, from the currently accepted model for the egress pathway of baculovirus. Electron microscopy showed that during infection, BmNPV-infected cells contained many newly formed multivesicular body (MVB)-like compartments that included mature virions at 30 h postinfection (p.i.). Immunoelectron microscopy demonstrated that the MVBs contained CD63, an MVB endosome marker, and GP64, a BmNPV fusion glycoprotein. MVB fusion with the PM and the release of mature virions, together with naked nucleocapsids, were observed at the cell surface. Furthermore, MVB egress mediated the translocation of SPΔnGP64 to the PM, which induced cell-cell fusion until 36 h p.i. This BV egress pathway can be partially inhibited by U18666A incubation and RNA interference targeting MVB biogenesis genes. Our findings indicate that BmNPV BVs are enveloped and released through MVBs via the cellular exosomal pathway, which is a subordinate BV egress pathway that produces virions with relatively inferior infectivity. This scenario has significant implications for the elucidation of the BmNPV BV envelopment pathway. IMPORTANCE BmNPV is a severe pathogen that infects mainly Bombyx mori, a domesticated insect of economic importance, and accounts for approximately 15% of economic losses in sericulture. BV production plays a key role in systemic BmNPV infection of larvae. Despite the progress made in the functional gene studies of BmNPV, BmNPV BV egress is ill-understood. This study reports a previously unreported MVB envelopment pathway in BmNPV BV egress. To our knowledge, this is the first report of a baculovirus using dual BV egress pathways. This specific BV egress mechanism explains the cause of the non-PM-localized SPΔnGP64-rescued gp64-null bacmid infectivity, elucidating the reason underlying the retention of SP by BmNPV GP64. The data obtained elucidate an alternate molecular mechanism of baculovirus BV egress.


Assuntos
Bombyx , Nucleopoliedrovírus , Animais , Corpos Multivesiculares , Liberação de Vírus , Linhagem Celular , Nucleopoliedrovírus/genética , Nucleopoliedrovírus/metabolismo , Proteínas Virais de Fusão/genética
9.
Dev Comp Immunol ; 140: 104612, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36473548

RESUMO

Salmon alphavirus (SAV) infection leads to severe pancreas disease (PD) with typical inflammatory responses in Atlantic salmon (Salmo salar) and rainbow trout (Oncorhynchus mykiss). Nsp2, an important nonstructural protein of SAV, can activate NF-κB signaling pathway to reduce inflammatory responses. However, the molecular mechanism remains unclear. In this study, the ML (279-421aa) of Nsp2 was revealed to be the key domain for activating NF-κB. We focused on a host protein, DEAD-box RNA helicase 3 (DDX3), that may interact with Nsp2 to regulate NF-κB-induced inflammatory. The interaction between DDX3 and Nsp2 was confirmed in vitro. Overexpression of DDX3 inhibited the activation of NF-κB by Nsp2. SAV Nsp2 relieves the inhibitory effect of DDX3 on NF-κB, thereby initiating the innate immune response. This study revealed the molecular mechanism of Nsp2-induced inflammatory response by targeting DDX3 to activate NF-κB, providing a theoretical basis for revealing the underlying infection mechanism and pathogenesis of SAV.


Assuntos
Infecções por Alphavirus , Alphavirus , Doenças dos Peixes , Oncorhynchus mykiss , Salmo salar , Animais , NF-kappa B , Alphavirus/fisiologia , Transdução de Sinais
10.
Virus Genes ; 59(2): 260-275, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36512182

RESUMO

Bombyx mori nucleopolyhedrovirus (BmNPV) GP64 is the key membrane fusion protein that mediates budded virus (BV) infection. We recently reported that BmNPV GP64's n-region of signal peptide (SP) blocked the SP-cleavage and mediated GP64 localization on the plasma membrane (PM); n-region (SP∆nGP64) absence caused GP64 intracellular localization, however, SP∆nGP64 was still incorporated into virion to generate BVs with lower infectivity. To better understand the biogenesis of the envelope of BmNPV BV, we conducted a label-free ESI mass spectrometry analysis of the envelope of purified BVs harboring PM localized GP64 or intracellular localized SP∆nGP64. The results indicated that 31 viral proteins were identified on the envelope, among which 15 were reported in other viruses. The other 16 proteins were first reported in BmNPV BV, including the BmNPV-specific protein BRO-A and proteins associated with vesicle transportation. Six proteins with significant intensity differences were detected in virions with differential localized GP64, and five specific proteins were identified in virions with GP64. Meanwhile, we identified 81 host proteins on the envelope, and seven lipoproteins were first identified in baculovirus virion; other 74 proteins are involved in the cytoskeleton, DNA-binding, vesicle transport, etc. In the meantime, eight and five specific host proteins were, respectively, identified in GP64 and SP∆nGP64's virions. The two virions shared 68 common host proteins, and 8 proteins were identified on their envelopes with a significant difference. This study provides new insight into the protein composition of BmNPV BV and a clue for further investigation of the budding mechanism of BmNPV.


Assuntos
Bombyx , Nucleopoliedrovírus , Animais , Proteômica , Linhagem Celular , Nucleopoliedrovírus/genética , Baculoviridae
11.
Fish Shellfish Immunol ; 129: 182-190, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36058437

RESUMO

Salmonid alphavirus (SAV) infection of Atlantic salmon (Salmo salar) and rainbow trout (Oncorhynchus mykiss) causes pancreas disease (PD) with typical inflammatory responses, such as necrosis of the exocrine pancreas, cardiomyopathy and skeletal myopathy. However, the pathogenic mechanism underlying SAV infection is still unclear. Inflammation may cause damage to the body, but it is a defense response against infection by pathogenic microorganisms, of which nuclear factor-kappa B (NF-κB) is the main regulator. This study revealed that SAV can activate NF-κB, of which the viral nonstructural protein Nsp2 is the major activating protein. SAV activates the NF-κB signaling pathway by simultaneously up-regulating TLR3, 7, 8 and then the expression of the signaling molecule myeloid differentiation factor 88 (Myd88) and tumor necrosis factor receptor-associated factor 6 (TRAF6). We found that Nsp2 can induce IκB degradation and p65 phosphorylation and transnucleation, and activate NF-κB downstream inflammatory cytokines. Nsp2 may simultaneously activate NF-κB through TLR3,7,8-dependent signaling pathways. Overexpression of Nsp2 can up-regulate mitochondrial antiviral signaling protein (MAVS) and then promote the expression of IFNa1 and antiviral protein Mx, which inhibits viral replication. This study shows that Nsp2 acts as a key activator protein for the NF-κB signaling pathway, which induces inflammation post-SAV infection. This study systematically analyzes the molecular mechanism of SAV activation of the NF-κB signaling pathway, and provides a theoretical basis for revealing the mechanism of innate immune response and inflammatory injury caused by SAV.


Assuntos
Infecções por Alphavirus , Alphavirus , Doenças dos Peixes , Oncorhynchus mykiss , Salmo salar , Alphavirus/fisiologia , Infecções por Alphavirus/veterinária , Animais , Antivirais , Citocinas/metabolismo , Inflamação/veterinária , Fator 88 de Diferenciação Mieloide/metabolismo , Proteínas de Resistência a Myxovirus/metabolismo , NF-kappa B/metabolismo , Oncorhynchus mykiss/metabolismo , Salmo salar/genética , Salmo salar/metabolismo , Transdução de Sinais , Fator 6 Associado a Receptor de TNF/metabolismo , Receptor 3 Toll-Like/metabolismo , Proteínas não Estruturais Virais
12.
Protein Expr Purif ; 200: 106156, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35987323

RESUMO

Glycoprotein (GP1,2) of the Ebola virus (EBOV) is the key membrane fusion protein, which is a key candidate protein for vaccine preparations. Previously, GP1,2 was expressed by Bombyx mori nucleopolyhedrovirus (BmNPV) expression vector system; however, few GP1,2 was incorporated into budded virus (BV) of BmNPV. To improve the incorporation efficiency of GP1,2 into the virion, the GP1,2 fusion with the cytoplasmic tail of GP64 of BmNPV was expressed in BmN cells by the BmNPV expression system. The BV was purified by ultracentrifugation, and GP1,2 expression in BV was detected by the antibody. The result indicated that a 532% increase in the relative GP1,2 densitometry signal was observed in constructs utilizing the GP64 C-terminal domain; moreover, the substitution of GP1,2 native signal peptide with GP64 signal peptide increased the incorporation efficiency by 34.6% in the relative GP1,2 densitometry signal. We revealed that the application of the cytoplasmic tail of BmNPV GP64 significantly increased the incorporation rate of GP1,2 into the BV envelope. This study lays a foundation for GP1,2 vaccine development.


Assuntos
Bombyx , Ebolavirus , Doença pelo Vírus Ebola , Animais , Linhagem Celular , Ebolavirus/genética , Glicoproteínas/genética , Nucleopoliedrovírus , Sinais Direcionadores de Proteínas
13.
Microbiol Spectr ; 10(4): e0191322, 2022 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-35938817

RESUMO

Bombyx mori nucleopolyhedrovirus (BmNPV) is the primary pathogen of silkworms that causes severe economic losses in sericulture. GP64 is the key membrane fusion protein that mediates budded virus (BV) fusion with the host cell membrane. Previously, we found that the n-region of the GP64 signal peptide (SP) is required for protein secretion and viral pathogenicity; however, our understanding of BmNPV GP64 remains limited. Here, we first reported that BmNPV GP64 retained its SP in the mature protein and virion in only host cells but did not retain in nonhost cells. Uncleaved SP mediates protein targeting to the cytomembrane or secretion in Bombyx mori cells. The exitance of the n-region extended the transmembrane helix length, which resulted in the cleavage site to be located in the helix structure and thus blocked cleavage from signal peptidase (SPase). Without the n-region, the protein fails to be transported to the cytomembrane, but this failure can be rescued by the cleavage site mutation of SP. Helix-breaking mutations in SP abolished protein targeting to the cytomembrane and secretion. Our results revealed a previously unrecognized mechanism by which SP of membrane fusion not only determines protein localization but also determines viral pathogenicity, which highlights the escape mechanism of SP from the cleavage by SPase. IMPORTANCE BmNPV is the primary pathogen of silkworms, which causes severe economic losses in sericulture. BmNPV and Autographa californica multiple nucleopolyhedrovirus (AcMNPV) are closely related group I alphabaculoviruses, but they exhibit nonoverlapping host specificity. Recent studies suppose that GP64 is a determinant of host range, while knowledge remains limited. In this study, we revealed that BmNPV GP64 retained its SP in host cells but not in nonhost cells, and the SP retention is required for GP64 secretion across the cytomembrane. This is the first report that a type I membrane fusion protein retained its SP in mature proteins and virions. Our results unveil the mechanism by which SP GP64 escapes cleavage and the role of SP in protein targeting. This study will help elucidate an important mechanistic understanding of BmNPV infection and host range specificity.


Assuntos
Bombyx , Nucleopoliedrovírus , Animais , Linhagem Celular , Proteínas de Fusão de Membrana/metabolismo , Nucleopoliedrovírus/genética , Nucleopoliedrovírus/metabolismo , Sinais Direcionadores de Proteínas
14.
Arch Insect Biochem Physiol ; 110(4): e21907, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35396759

RESUMO

Neddylation is a posttranslational modification that is similar to ubiquitination, and involved in some critical biological processes, such as DNA repair, transcription regulation, and ubiquitin-proteasome pathway. Recently, it was found that neddylation inhibitor MLN4924 has potent antiviral activity against human viruses including herpes simplex virus (HSV)-1, HSV-2, and influenza viruses. Here, we report that MLN4924 could dramatically and dose-dependently inhibits the propagation, formation of budding virus (BV) and occlusion body (OB) of a lepidopteran virus-Bombyx mori nucleopolyhedrovirus (BmNPV), impaired OB assembly. In addition, the neddylation modification protein NEDD8 is colocalized with aggresome and autophagosome. Our findings suggest that inhibiting neddylation could be an antibaculovirus strategy and MLN4924 may be used as candidate drug for that purpose.


Assuntos
Bombyx , Nucleopoliedrovírus , Animais , Bombyx/genética , Humanos , Nucleopoliedrovírus/fisiologia , Processamento de Proteína Pós-Traducional , Replicação Viral
15.
Arch Virol ; 167(4): 1051-1059, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35201427

RESUMO

Membrane fusion is a key step in enveloped virus infection, releasing the viral genome into the cytoplasm to initiate infection. Bombyx mori nucleopolyhedrovirus (BmNPV) is an enveloped DNA virus that mainly infects silkworms. Information about membrane fusion of BmNPV with host cells is still limited. In this study, BmN cells were pretreated with ??ammonium chloride??, and infection with BmNPV was allowed to occur naturally through endocytosis or artificially through low-pH-induced fusion with the plasma membrane, after which the cells were subjected to RNA-seq. The results indicated that a few endoplasmic reticulum-associated proteins (ERAPs) were among the common upregulated DEGs, including BiP, CRT, and HSP90, and this upregulation was confirmed by q-PCR. Knockdown of BiP, CRT, and HSP90 expression by siRNA resulted in significant inhibition of BmNPV infection. This study suggests that ERAPs may be involved in the BmNPV membrane fusion process during infection.


Assuntos
Bombyx , Nucleopoliedrovírus , Animais , Retículo Endoplasmático , Estresse do Retículo Endoplasmático , Nucleopoliedrovírus/genética , RNA-Seq
16.
Microbiol Spectr ; 9(3): e0172521, 2021 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-34937190

RESUMO

The signal peptide (SP) of integrated membrane proteins is removed cotranslationally or posttranslationally in the endoplasmic reticulum, while GP64, a membrane fusion protein of Bombyx mori nucleopolyhedrovirus (BmNPV), retains its SP in the mature protein and virion. In this study, we revealed that uncleaved SP is a key determinant with additional functions in infection. First, uncleaved SP endows BmNPV with strong virulence; second, SP retention-induced BmNPV infection depends on cholesterol recognition amino acid consensus domain 1 (CRAC1) and CRAC2. In contrast, the recombinant virus with SP-cleaved GP64 has reduced infectivity, and only CRAC2 is required for BmNPV infection. Furthermore, we showed that cholesterol in the plasma membrane is an important fusion receptor that interacts with CRAC2 of GP64. Our study suggested that BmNPV GP64 is a key cholesterol-binding protein and uncleaved SP determines GP64's unique dependence on the CRAC domains. IMPORTANCE BmNPV is a severe pathogen that mainly infects silkworms. GP64 is the key membrane fusion protein that mediates BmNPV infection, and some studies have indicated that cholesterol and lipids are involved in BmNPV infection. A remarkable difference from other membrane fusion proteins is that BmNPV GP64 retains its SP in the mature protein, but the cause is still unclear. In this study, we investigated the reason why BmNPV retains this SP, and its effects on protein targeting, virulence, and CRAC dependence were revealed by comparison of recombinant viruses harboring SP-cleaved or uncleaved GP64. Our study provides a basis for understanding the dependence of BmNPV infection on cholesterol/lipids and host specificity.


Assuntos
Motivos de Aminoácidos/genética , Bombyx/virologia , Colesterol/metabolismo , Proteínas de Fusão de Membrana/metabolismo , Nucleopoliedrovírus/genética , Sinais Direcionadores de Proteínas/genética , Animais , Linhagem Celular , Membrana Celular/química , Especificidade de Hospedeiro/genética , Especificidade de Hospedeiro/fisiologia , Fusão de Membrana/fisiologia , Proteínas de Fusão de Membrana/genética , Nucleopoliedrovírus/patogenicidade , Virulência/genética
17.
ACS Omega ; 6(18): 12223-12228, 2021 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-34056376

RESUMO

Rapid and sensitive pathogenic bacterial identification and isolation from complicated clinical specimens are of great importance for the early diagnosis and prevention of osteomyelitis. Herein, we proposed a novel methicillin-resistant Staphylococcus aureus (MRSA) detection strategy through two specially designed streptavidin magnetic bead-based probes, including a capture probe and a report probe. In detail, the capture probe takes the responsibility to specially bind with the surface protein of MRSA and leads to the liberation of the promoter which could subsequently initiate report probe-based signal amplification. Afterward, the hybridization of the promoter probe with the report probe could then transform the protruding 3' terminus of template DNA in the report probe into a blunt end. With the assistance of Exo III, the template could be digested to liberate the promoter to form a recycle and to liberate the biprobe to induce the following rolling circle amplification (RCA)-based signal amplification. Through the integration of the Exo III-assisted recycle and RCA-based signal amplification, the proposed method exhibited a favorable detection performance.

18.
Curr Microbiol ; 78(2): 490-501, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33386938

RESUMO

GP64 is the key membrane fusion protein of Group I baculovirus, and while the Bombyx mori nucleopolyhedrovirus (BmNPV) GP64 contains a longer n-region (18 amino acid) of the signal peptide than does the Autographa californica multiple nucleopolyhedrovirus (AcMNPV), the function of the n-region has not been determined. In this study, we first showed that n-region is required for membrane protein localization in BmN cells, then the transcriptome sequencing was conducted on proteins guided by different signal peptide regions, and the results were analyzed and validated by quantitative PCR and luciferase assays. The results indicated that 1049 differentially expressed genes (DEGs) were identified among the different region of signal peptides and the control. With the n-region, the protein export pathway was upregulated significantly, the Wnt-1 signaling pathway was downregulated, and BiP was significantly activated by the GP64 full-length signal peptide. Furthermore, RNA interference on BiP efficiently increased luciferase secretion. These results indicate that the GP64 n-region plays a key role in protein expression and regulation.


Assuntos
Bombyx , Sinais Direcionadores de Proteínas , Sequência de Aminoácidos , Aminoácidos , Animais , Proteínas de Transporte , Linhagem Celular , Imunoglobulinas , Nucleopoliedrovírus , Sinais Direcionadores de Proteínas/genética , Análise de Sequência de RNA
19.
Dis Aquat Organ ; 139: 25-33, 2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32351234

RESUMO

The major antigenic protein of infectious hematopoietic necrosis virus (IHNV) is the surface glycoprotein G, which contains neutralizing epitopes that induce the production of immune neutralizing antibodies. In this study, the IHNV G gene sequence was truncated according to bioinformatics principles and then recombinantly expressed via an E. coli expression system. We then assessed the specific antibody immunoglobin M (IgM) levels of rainbow trout immunized with recombinant truncated G protein (emulsified with Freund's incomplete adjuvant), and showed that antibody IgM levels of immunized fish were significantly higher than in the control group (p < 0.01). The mRNA expression levels of interferon 1 (IFN1) and interleukin-8 (IL-8) were also up-regulated significantly (p < 0.01) in head kidneys and spleens of rainbow trout immunized with recombinant truncated G protein. Also, after challenge with wild-type IHNV HLJ-09 virus on Day 28, rainbow trout immunized with recombinant truncated G protein showed cumulative survival rates of 60%. These results indicate that the truncated G protein of IHNV expressed by the E. coli prokaryotic expression system can be used as a candidate immunogen for an IHNV subunit vaccine, which lays a theoretical foundation for the study of further potential IHNV subunit vaccines.


Assuntos
Doenças dos Peixes , Vírus da Necrose Hematopoética Infecciosa , Oncorhynchus mykiss , Animais , Resistência à Doença , Escherichia coli
20.
Viruses ; 11(11)2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31731691

RESUMO

Ebola virus (EBOV) disease outbreaks have resulted in many fatalities, yet no licensed vaccines are available to prevent infection. Recombinant glycoprotein (GP) production may contribute to finding a cure for Ebola virus disease, which is the key candidate protein for vaccine preparation. To explore GP1,2 expression in BmN cells, EBOV-GP1,2 with its native signal peptide or the GP64 signal peptide was cloned and transferred into a normal or gp64 null Bombyx mori nucleopolyhedrovirus (BmNPV) bacmid via transposition. The infectivity of the recombinant bacmids was investigated after transfection, expression and localization of EBOV-GP were investigated, and cell morphological changes were analyzed by TEM. The GP64 signal peptide, but not the GP1,2 native signal peptide, caused GP1,2 localization to the cell membrane, and the differentially localized GP1,2 proteins were cleaved into GP1 and GP2 fragments in BmN cells. GP1,2 expression resulted in dramatic morphological changes in BmN cells in the early stage of infection. However, GP1,2 expression did not rescue GP64 deficiency in BmNPV infection. This study provides a better understanding of GP expression and processing in BmN cells, which may lay a foundation for EBOV-GP expression using the BmNPV baculovirus expression system.


Assuntos
Ebolavirus/metabolismo , Glicoproteínas/genética , Glicoproteínas/metabolismo , Interações Microbianas , Nucleopoliedrovírus/genética , Processamento de Proteína Pós-Traducional , Proteínas Virais , Animais , Linhagem Celular , Células Cultivadas , Ebolavirus/genética , Expressão Gênica , Técnicas de Silenciamento de Genes , Proteínas Recombinantes , Replicação Viral
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