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1.
PLoS Pathog ; 20(7): e1012398, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39038050

RESUMEN

Inflammasomes play pivotal roles in inflammation by processing and promoting the secretion of IL-1ß. Caspase-1 is involved in the maturation of IL-1ß and IL-18, while human caspase-4 specifically processes IL-18. Recent structural studies of caspase-4 bound to Pro-IL-18 reveal the molecular basis of Pro-IL-18 activation by caspase-4. However, the mechanism of caspase-1 processing of pro-IL-1ß and other IL-1ß-converting enzymes remains elusive. Here, we observed that swine Pro-IL-1ß (sPro-IL-1ß) exists as an oligomeric precursor unlike monomeric human Pro-IL-1ß (hPro-IL-1ß). Interestingly, Seneca Valley Virus (SVV) 3C protease cleaves sPro-IL-1ß to produce mature IL-1ß, while it cleaves hPro-IL-1ß but does not produce mature IL-1ß in a specific manner. When the inflammasome is blocked, SVV 3C continues to activate IL-1ß through direct cleavage in porcine alveolar macrophages (PAMs). Through molecular modeling and mutagenesis studies, we discovered that the pro-domain of sPro-IL-1ß serves as an 'exosite' with its hydrophobic residues docking into a positively charged 3C protease pocket, thereby directing the substrate to the active site. The cleavage of sPro-IL-1ß generates a monomeric and active form of IL-1ß, initiating the downstream signaling. Thus, these studies provide IL-1ß is an inflammatory sensor that directly detects viral protease through an independent pathway operating in parallel with host inflammasomes.


Asunto(s)
Proteasas Virales 3C , Inflamasomas , Interleucina-1beta , Picornaviridae , Proteínas Virales , Animales , Interleucina-1beta/metabolismo , Proteasas Virales 3C/metabolismo , Porcinos , Humanos , Proteínas Virales/metabolismo , Inflamasomas/metabolismo , Inflamación/metabolismo , Infecciones por Picornaviridae/metabolismo , Infecciones por Picornaviridae/virología , Cisteína Endopeptidasas/metabolismo , Especificidad de la Especie , Macrófagos Alveolares/virología , Macrófagos Alveolares/metabolismo
2.
PLoS Pathog ; 19(5): e1011411, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37253057

RESUMEN

Seneca virus A (SVA) is an emerging novel picornavirus that has recently been identified as the causative agent of many cases of porcine vesicular diseases in multiple countries. In addition to cleavage of viral polyprotein, the viral 3C protease (3Cpro) plays an important role in the regulation of several physiological processes involved in cellular antiviral responses by cleaving critical cellular proteins. Through a combination of crystallography, untargeted lipidomics, and immunoblotting, we identified the association of SVA 3Cpro with an endogenous phospholipid molecule, which binds to a unique region neighboring the proteolytic site of SVA 3Cpro. Our lipid-binding assays showed that SVA 3Cpro displayed preferred binding to cardiolipin (CL), followed by phosphoinositol-4-phosphate (PI4P) and sulfatide. Importantly, we found that the proteolytic activity of SVA 3Cpro was activated in the presence of the phospholipid, and the enzymatic activity is inhibited when the phospholipid-binding capacity decreased. Interestingly, in the wild-type SVA 3Cpro-substrate peptide structure, the cleavage residue cannot form a covalent binding to the catalytic cysteine residue to form the acyl-enzyme intermediate observed in several picornaviral 3Cpro structures. We observed a decrease in infectivity titers of SVA mutants harboring mutations that impaired the lipid-binding ability of 3Cpro, indicating a positive regulation of SVA infection capacity mediated by phospholipids. Our findings reveal a mutual regulation between the proteolytic activity and phospholipid-binding capacity in SVA 3Cpro, suggesting that endogenous phospholipid may function as an allosteric activator that regulate the enzyme's proteolytic activity during infection.


Asunto(s)
Cisteína Endopeptidasas , Picornaviridae , Animales , Porcinos , Cisteína Endopeptidasas/metabolismo , Proteasas Virales 3C/metabolismo , Péptido Hidrolasas/metabolismo , Regulación Alostérica , Fosfolípidos , Proteínas Virales/metabolismo
3.
PLoS Pathog ; 19(9): e1011641, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37708231

RESUMEN

RNA viruses cause numerous infectious diseases in humans and animals. The crosstalk between RNA viruses and the innate DNA sensing pathways attracts increasing attention. Recent studies showed that the cGAS-STING pathway plays an important role in restricting RNA viruses via mitochondria DNA (mtDNA) mediated activation. However, the mechanisms of cGAS mediated innate immune evasion by RNA viruses remain unknown. Here, we report that seneca valley virus (SVV) protease 3C disrupts mtDNA mediated innate immune sensing by cleaving porcine cGAS (pcGAS) in a species-specific manner. Mechanistically, a W/Q motif within the N-terminal domain of pcGAS is a unique cleavage site recognized by SVV 3C. Three conserved catalytic residues of SVV 3C cooperatively contribute to the cleavage of pcGAS, but not human cGAS (hcGAS) or mouse cGAS (mcGAS). Additionally, upon SVV infection and poly(dA:dT) transfection, pcGAS and SVV 3C colocalizes in the cells. Furthermore, SVV 3C disrupts pcGAS-mediated DNA binding, cGAMP synthesis and interferon induction by specifically cleaving pcGAS. This work uncovers a novel mechanism by which the viral protease cleaves the DNA sensor cGAS to evade innate immune response, suggesting a new antiviral approach against picornaviruses.


Asunto(s)
Nucleotidiltransferasas , Péptido Hidrolasas , Picornaviridae , Animales , Humanos , Ratones , ADN Mitocondrial , Endopeptidasas , Mitocondrias , Picornaviridae/fisiología , Porcinos , Nucleotidiltransferasas/metabolismo
4.
Anal Chem ; 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-39279132

RESUMEN

Biomimetic nanoengineering empowers nanoparticles with enhanced biointerfacial capabilities by directly utilizing cell membranes (CMs) of natural origin. This top-down technique provides a powerful tool for the screening of potentially active compounds in complex matrices. Herein, cartilaginous end plate (CEP) cell membrane biomimetic Nile red (NR)-loaded zeolitic imidazolate frameworks-8 (ZIF-8) modified magnetic graphene oxide (CEP/MGO-ZIF-8-NR) nanocomposites with enhanced stability were accurately prepared by chemical bonding and used as a drug discovery platform for the specific identification and effective extraction of drug leads with anti-intervertebral disc degeneration (IDD) in Yaobitong capsules (YBTCs). The constructed CEP/MGO-ZIF-8-NR exhibited excellent magnetic properties, fluorescence properties, and stability. In addition, drug binding experiments showed that the CEP/MGO-ZIF-8-NR nanocomposites possessed higher adsorption capacity, faster adsorption rate, and superior selectivity compared with uncoated MGO-ZIF-8-NR. Ultimately, four potential bioactive molecules, including ginsenoside Ro, ginsenoside Rg1, astringin, and chikusetsusaponin V methyl ester, were successfully screened and identified in vitro from YBTC. The results of the CCK-8 assay and BrdU ELISA kit showed that the screened compounds promoted CEP cell proliferation in a concentration-dependent manner. Cellular distribution experiments revealed that CEP/MGO-ZIF-8-NR could rapidly escape from lysosomes and into the cytoplasm. And the pharmacological activity of these compounds was further confirmed by real-time cytomorphological imaging of CEP cells by confocal laser scanning microscopy (CLSM). Overall, this surface engineering strategy endows bioaffinity sample pretreatment materials with tremendous versatility, improves drug screening efficiency, and broadens the horizons and methodologies for drug lead discovery.

5.
Microb Cell Fact ; 23(1): 222, 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39118114

RESUMEN

BACKGROUND: A cost-effective Escherichia coli expression system has gained popularity for producing virus-like particle (VLP) vaccines. However, the challenge lies in balancing the endotoxin residue and removal costs, as residual endotoxins can cause inflammatory reactions in the body. RESULTS: In this study, porcine parvovirus virus-like particles (PPV-VLPs) were successfully assembled from Decreased Endotoxic BL21 (BL21-DeE), and the effect of structural changes in the lipid A of BL21 on endotoxin activity, immunogenicity, and safety was investigated. The lipopolysaccharide purified from BL21-DeE produced lower IL-6 and TNF-α than that from wild-type BL21 (BL21-W) in both RAW264.7 cells and BALB/c mice. Additionally, mice immunized with PPV-VLP derived form BL21-DeE (BL21-DeE-VLP) showed significantly lower production of inflammatory factors and a smaller increase in body temperature within 3 h than those immunized with VLP from BL21-W (BL21-W-VLP) and endotoxin-removed VLP (ReE-VLP). Moreover, mice in the BL21-DeE-VLP immunized group had similar levels of serum antibodies as those in the BL21-W-VLP group but significantly higher levels than those in the ReE-VLP group. Furthermore, the liver, lungs, and kidneys showed no pathological damage compared with the BL21-W-VLP group. CONCLUSION: Overall, this study proposes a method for producing VLP with high immunogenicity and minimal endotoxin activity without chemical or physical endotoxin removal methods. This method could address the issue of endotoxin residues in the VLP and provide production benefits.


Asunto(s)
Endotoxinas , Escherichia coli , Lípido A , Ratones Endogámicos BALB C , Parvovirus Porcino , Vacunas de Partículas Similares a Virus , Animales , Ratones , Escherichia coli/genética , Escherichia coli/metabolismo , Parvovirus Porcino/inmunología , Parvovirus Porcino/genética , Vacunas de Partículas Similares a Virus/inmunología , Endotoxinas/inmunología , Células RAW 264.7 , Lípido A/inmunología , Lípido A/análogos & derivados , Interleucina-6/inmunología , Factor de Necrosis Tumoral alfa/metabolismo , Femenino , Porcinos , Lipopolisacáridos/inmunología
6.
Arch Virol ; 169(3): 67, 2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38451379

RESUMEN

Porcine circovirus type 4 (PCV4), first identified in 2019 as a newly emerging pathogen, has been found in several provinces of China, as well as in Korea and Thailand. Since PCV4 is not included in immunization programs, epidemiological investigations should be conducted for detection of anti-PCV4 antibodies. Virus-like particles (VLPs) are frequently used for serological analysis of pathogen infections. However, there have been no reports on using PCV4 VLPs for serological investigation of PCV4 infection. In this study, we generated self-assembled PCV4 VLPs using an E. coli expression system, purified them using a two-step process, and used them to develop an indirect ELISA. This ELISA method was found to be highly specific, sensitive, and repeatable, making it suitable for PCV4 antibody detection in serum samples. Finally, the ELISA was used to analyze 422 serum samples collected from across several regions in China, 134 of which tested positive. Thus, the PCV4-VLP-based ELISA can effectively detect antibodies against PCV4 in serum samples, making it a useful tool for PCV4 epidemiology.


Asunto(s)
Circovirus , Animales , Porcinos , Circovirus/genética , Escherichia coli , Anticuerpos , Ensayo de Inmunoadsorción Enzimática , China
7.
World J Surg Oncol ; 22(1): 22, 2024 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-38245723

RESUMEN

BACKGROUND: Transforming growth factor ß (TGFß) is a critical regulator of lung metastasis of breast cancer and is correlated with the prognosis of breast cancer. However, not all TGFß stimulated genes were functional and prognostic in breast cancer lung metastatic progress. In this study, we tried to determine the prognosis of TGFß stimulated genes in breast cancer. METHODS: TGFß stimulated genes in MDA-MB-231 cells and lung metastasis-associated genes in LM2-4175 cells were identified through gene expression microarray. The prognosis of the induced gene (TGFBI) in breast cancer was determined through bioinformatics analysis and validated using tissue microarray. The immune infiltrations of breast cancer were determined through "ESTIMATE" and "TIMER". RESULTS: TGFBI was up-regulated by TGFß treatment and over-expressed in LM2-4175 cells. Through bioinformatics analysis, we found that higher expression of TGFBI was associated with shorted lung metastasis-free survival, relapse-free survival, disease-free survival, and overall survival of breast cancer. Moreover, the prognosis of TGFBI was validated in 139 Chinese breast cancer patients. Chinese breast cancer patients with higher TGFBI expression had lower overall survival. Correspondingly, breast cancer patients with higher TGFBI methylation had higher overall survival. TGFBI was correlated with the score of the TGFß signaling pathway and multiple immune-related signaling pathways in breast cancer. The stromal score, immune score, and the infiltrations of immune cells were also correlated with TGFBI expression in breast cancer. CONCLUSIONS: TGFß-induced gene TGFBI was correlated with the prognosis and immune infiltrations of breast cancer.


Asunto(s)
Neoplasias de la Mama , Neoplasias Pulmonares , Humanos , Femenino , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Recurrencia Local de Neoplasia , Pronóstico , Factor de Crecimiento Transformador beta/genética , Factor de Crecimiento Transformador beta/metabolismo , Neoplasias Pulmonares/patología , Factores de Crecimiento Transformadores , Línea Celular Tumoral
8.
Inflammopharmacology ; 32(1): 873-883, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38227094

RESUMEN

Lignan-rich beans, nuts, and various seeds are the main foods with antioxidative and hormone-modulating activities. Although the role of lignans in mediating hormone-dependent cancers and cardiovascular diseases is well characterized, the function of lignans in anti-arthritic activity and its underlying mechanisms remain unknown. Three new lignan derivatives, (-)-nortrachelogenin, trachelogenin, and matairesinol, were extracted from Loranthus parasiticus. After establishing the collagen-induced arthritis (CIA) model by intradermal injection of collagen, rats were treated with three new lignan derivatives ((-)-nortrachelogenin: 37%; trachelogenin: 27%; matairesinol: 25.7%) at a concentration of 50 mg/kg and 100 mg/kg, or methotrexate at 0.3 mg/kg. Mixed lignan derivatives significantly attenuated the immune responses in the joints of CIA rats, leading to lower levels of proinflammatory cytokines (IL-6 and TNF-α) and higher levels of free androgen in the serum compared to the CIA model. The results of molecular docking using AutoDock Vina showed that the lignan derivative (-)-nortrachelogenin was the most effective compound for binding to sex hormone-binding globulin (SHBG), thus inhibiting the activity of NFκB in LPS-stimulated macrophages. In this study, (-)-nortrachelogenin was identified as a novel natural lignan derivative with previously unrecognized anti-inflammatory activity. Its molecular mechanism appears related to the regulation of the NFκB/SHBG pathway. Our findings suggest that further application of sex hormone-like compounds in the treatment of rheumatoid arthritis and the potential clinical applications of (-)-nortrachelogenin are promising.


Asunto(s)
4-Butirolactona/análogos & derivados , Artritis Experimental , Furanos , Lignanos , Ratas , Animales , Artritis Experimental/inducido químicamente , Artritis Experimental/tratamiento farmacológico , Artritis Experimental/metabolismo , Globulina de Unión a Hormona Sexual , Simulación del Acoplamiento Molecular , Lignanos/farmacología , Lignanos/uso terapéutico , Hormonas/efectos adversos
9.
Clin Genet ; 103(4): 413-423, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36537221

RESUMEN

The fimbrin protein family contains a variety of proteins, among which Plastin1 (PLS1) is an important member. According to recent studies, variations in the coding region of the PLS1 gene are associated with the development of deafness. However, the molecular mechanism of deafness caused by PLS1 gene variants remains unknown. Whole-exome sequencing was performed on hearing-impaired family members and hearing family members to identify pathogenic variants, followed by Sanger sequencing. A minigene assay was conducted to investigate the effect of the variant on PLS1 mRNA splicing. The pathogenicity of the variant was further investigated in zebrafish. RNA-sequencing (RNA-seq) was performed to analyze the dysregulation of downstream signaling pathways caused by knockdown of PLS1 expression. We identified a novel variant, PLS1 c.981+1G>A, in a large Chinese family with hearing loss and showed that the variant is responsible for the occurrence of hearing loss by inducing exon 8 skipping. The variant caused abnormal inner ear phenotypes, characterized by decreases in the mean otolith distance, anterior otolith diameter, posterior otolith diameter, cochlear diameter, and swimming speed and distance in zebrafish. Furthermore, silencing PLS1 expression significantly upregulated the expression of genes in the PI3K-Akt signaling pathway, including Col6a3, Spp1, Itgb3 and hepatocyte growth factor (Hgf). PLS1 c.981+1G>A is a novel pathogenic variant causing hearing loss by inducing exon 8 skipping. Upregulation of the expression of genes in the PI3K-Akt signaling pathway plays an important role in the pathogenesis caused by variants in the PLS1 gene.


Asunto(s)
Sordera , Pérdida Auditiva Sensorineural , Pérdida Auditiva , Animales , Humanos , Pez Cebra/genética , Proteínas Proto-Oncogénicas c-akt/genética , Fosfatidilinositol 3-Quinasas/genética , Pérdida Auditiva Sensorineural/genética , Sordera/genética , Pérdida Auditiva/genética , Linaje , Mutación
10.
BMC Ophthalmol ; 23(1): 176, 2023 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-37095443

RESUMEN

BACKGROUND: To evaluate the prevalence and associated health and lifestyle factors of myopic maculopathy (MM) in a northern Chinese industrial city. METHODS: The cross-sectional Kailuan Eye Study included subjects who participated in the longitudinal Kailuan Study in 2016. Ophthalmologic and general examinations were performed on all the participants. MM was graded based on fundus photographs using the International Photographic Classification and Grading System. The prevalence of MM was evaluated. Univariate and multiple logistic regression were adopted to evaluated risk factors of MM. RESULTS: The study included 8330 participants with gradable fundus photographs for MM and ocular biometry data. The prevalence of MM was 1.11% (93/8330; 95% confidence interval [CI] 0.89-1.33%). Diffuse chorioretinal atrophy, patchy chorioretinal atrophy, macular atrophy, and plus lesions were observed in 72 (0.9%), 15 (0.2%), 6 (0.007%), and 32 eyes (0.4%), respectively. MM was more common in eyes with longer axial length (OR 4.517; 95%CI 3.273 to 6.235) and in participants with hypertension (OR 3.460; 95%CI 1.152 to 10.391), and older age (OR 1.084; 95%CI 1.036 to 1.134). CONCLUSIONS: The MM was present in 1.11% of the northern Chinese individuals 21 years or older and the associate factors include longer axial length, older age, and hypertension.


Asunto(s)
Degeneración Macular , Miopía Degenerativa , Degeneración Retiniana , Enfermedades de la Retina , Humanos , Agudeza Visual , Prevalencia , Estudios Transversales , China/epidemiología , Estilo de Vida , Atrofia
11.
BMC Pediatr ; 22(1): 376, 2022 06 29.
Artículo en Inglés | MEDLINE | ID: mdl-35764946

RESUMEN

BACKGROUND: Previously, we had analyzed the prognosis of E2F transcription factors across adult tumor types. However, the expressions and prognosis of E2F transcription factors in pediatric neuroblastoma have not yet been fully studied. METHODS: The prognosis of E2F transcription factors was determined in four independent pediatric neuroblastoma cohorts from Therapeutically Applicable Research to Generate Effective Treatments (TARGET), Gene Expression Omnibus (GEO) and European ArrayExpres datasets using Kaplan-Meier and cox regression analysis. RESULTS: E2F regulated gene set was associated with the event free survival and the overall survival of neuroblastoma. E2F1 and E2F3 were prognostic factors in all four independent pediatric neuroblastoma cohorts. Over-expressions of E2F1 or E2F3 were correlated with the shorted event free survival and overall survival of neuroblastoma. Expression levels of E2F1 and E2F3 were higher in neuroblastoma patients with MYCN amplification or age at diagnosis ≥ 18 months. Moreover, the prognostic significance of E2F1 or E2F3 in neuroblastoma was independent of MYCN amplification and age of diagnosis. Combinations of E2F1, E2F3 with MYCN amplification or age of diagnosis achieved better prognosis of neuroblastoma. Identification of 234 genes were associated with E2F1 and E2F3 expressions in neuroblastoma and those genes were significantly enriched in cell cycle signaling pathway. Also, higher scores of cell cycle signaling pathway were correlated with the adverse prognosis of neuroblastoma. CONCLUSIONS: E2F transcription factors E2F1 and E2F3 were prognostic makers of neuroblastoma.


Asunto(s)
Factor de Transcripción E2F1 , Neuroblastoma , Niño , Factor de Transcripción E2F1/genética , Factor de Transcripción E2F3/genética , Humanos , Proteína Proto-Oncogénica N-Myc , Neuroblastoma/genética , Pronóstico
12.
J Virol ; 94(17)2020 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-32581104

RESUMEN

Cap-independent translation initiation on picornavirus mRNAs is mediated by an internal ribosomal entry site (IRES) in the 5' untranslated region. The regulation of internal initiation requires the interaction of IRES-transacting factors (ITAFs) with the IRES. In this study, we identified a novel ITAF, heterogeneous nuclear ribonucleoprotein K (hnRNP K), which negatively regulates foot-and-mouth disease virus (FMDV) translation and viral replication. Further investigation revealed that the KH2 and KH3 domains of hnRNP K directly bind to domains II, III, and IV of the FMDV IRES, resulting in the inhibition of IRES-mediated translation by interfering with the recognition of another positive ITAF, polypyrimidine tract-binding protein (PTB). Conversely, hnRNP K-mediated inhibition was antagonized by the viral 3C protease through the cleavage of hnRNP K at the Glu-364 residue during FMDV infection. Interestingly, the N-terminal cleavage product, hnRNP K1-364, retained partial inhibitory effects on IRES activity, whereas the C-terminal cleavage product, hnRNP K364-465, became a positive regulator of FMDV replication. Our findings expand the current understanding of virus-host interactions concerning viral recruitment and the modulation of ITAFs, providing new insights into translational control during viral infection.IMPORTANCE The translation of picornaviral genome RNA mediated by the internal ribosomal entry site (IRES) is a crucial step for virus infections. Virus-host interactions play a critical role in the regulation of IRES-dependent translation, but the regulatory mechanism remains largely unknown. In this study, we identified an ITAF, hnRNP K, that negatively regulates FMDV replication by inhibiting viral IRES-mediated translation. In addition, we describe a novel translational regulation mechanism involving the proteolytic cleavage of hnRNP K by FMDV protease 3C. The cleavage of hnRNP K yields two cleavage products with opposite functions: the cleavage product hnRNP K1-364 retains a partial inhibitory effect on IRES activity, and the cleavage product hnRNP K364-465 becomes a positive regulator of FMDV replication. Our findings shed light on the effect of a novel ITAF on the translational regulation of picornavirus and provide new insights into translational control during viral infection.


Asunto(s)
Cisteína Endopeptidasas/metabolismo , Virus de la Fiebre Aftosa/fisiología , Ribonucleoproteína Heterogénea-Nuclear Grupo K/metabolismo , Sitios Internos de Entrada al Ribosoma/fisiología , Transactivadores/metabolismo , Proteínas Virales/metabolismo , Replicación Viral/fisiología , Proteasas Virales 3C , Animales , Línea Celular , Cricetinae , Virus de la Fiebre Aftosa/genética , Regulación Viral de la Expresión Génica , Células HEK293 , Humanos , Proteína de Unión al Tracto de Polipirimidina , ARN Mensajero , Proteínas Virales/genética
13.
J Virol ; 94(10)2020 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-32161169

RESUMEN

Upon infection, the highly structured 5' untranslated region (5' UTR) of picornavirus is involved in viral protein translation and RNA synthesis. As a critical element in the 5' UTR, the internal ribosome entry site (IRES) binds to various cellular proteins to function in the processes of picornavirus replication. Foot-and-mouth disease virus (FMDV) is an important member in the family Picornaviridae, and its 5' UTR contains a functional IRES element. In this study, the cellular heterogeneous nuclear ribonucleoprotein L (hnRNP L) was identified as an IRES-binding protein for FMDV by biotinylated RNA pulldown assays, mass spectrometry (MS) analysis, and determination of hnRNP L-IRES interaction regions. Further, we found that hnRNP L inhibited the growth of FMDV through binding to the viral IRES and that the inhibitory effect of hnRNP L on FMDV growth was not due to FMDV IRES-mediated translation, but to influence on viral RNA synthesis. Finally, hnRNP L was demonstrated to coimmunoprecipitate with RNA-dependent RNA polymerase (3Dpol) in an FMDV RNA-dependent manner in the infected cells. Thus, our results suggest that hnRNP L, as a critical IRES-binding protein, negatively regulates FMDV replication by inhibiting viral RNA synthesis, possibly by remaining in the replication complex.IMPORTANCE Picornaviruses, as a large family of human and animal pathogens, cause a bewildering array of disease syndromes. Many host factors are implicated in the pathogenesis of these viruses, and some proteins interact with the viral IRES elements to affect function. Here, we report for the first time that cellular hnRNP L specifically interacts with the IRES of the picornavirus FMDV and negatively regulates FMDV replication through inhibiting viral RNA synthesis. Further, our results showed that hnRNP L coimmunoprecipitates with FMDV 3Dpol in a viral RNA-dependent manner, suggesting that it may remain in the replication complex to function. The data presented here would facilitate further understanding of virus-host interactions and the pathogenesis of picornavirus infections.


Asunto(s)
Regiones no Traducidas 5' , Virus de la Fiebre Aftosa/fisiología , Ribonucleoproteína Heterogénea-Nuclear Grupo L/metabolismo , Sitios Internos de Entrada al Ribosoma/fisiología , ARN Viral/biosíntesis , Replicación Viral/fisiología , Animales , Línea Celular , Virus de la Fiebre Aftosa/genética , Regulación Viral de la Expresión Génica , Técnicas de Inactivación de Genes , Células HEK293 , Ribonucleoproteína Heterogénea-Nuclear Grupo L/genética , Interacciones Microbiota-Huesped/fisiología , Humanos , Inmunoprecipitación , Unión Proteica , ARN Viral/genética , Transcriptoma
14.
J Virol ; 95(1)2020 12 09.
Artículo en Inglés | MEDLINE | ID: mdl-33028719

RESUMEN

The low fidelity of foot-and-mouth disease virus (FMDV) RNA-dependent RNA polymerase allows FMDV to exhibit high genetic diversity. Previously, we showed that the genetic diversity of FMDV plays an important role in virulence in suckling mice. Here, we mutated the amino acid residue Phe257, located in the finger domain of FMDV polymerase and conserved across FMDV serotypes, to a cysteine (F257C) to study the relationship between viral genetic diversity, virulence, and transmissibility in natural hosts. The single amino acid substitution in FMDV polymerase resulted in a high-fidelity virus variant, rF257C, with growth kinetics indistinguishable from those of wild-type (WT) virus in cell culture, but it displayed smaller plaques and impaired fitness in direct competition assays. Furthermore, we found that rF257C was attenuated in vivo in both suckling mice and pigs (one of its natural hosts). Importantly, contact exposure experiments showed that the rF257C virus exhibited reduced transmissibility compared to that of wild-type FMDV in the porcine model. This study provides evidence that FMDV genetic diversity is important for viral virulence and transmissibility in susceptible animals. Given that type O FMDV exhibits the highest genetic diversity among all seven serotypes of FMDV, we propose that the lower polymerase fidelity of the type O FMDV could contribute to its dominance worldwide.IMPORTANCE Among the seven serotypes of FMDV, serotype O FMDV have the broadest distribution worldwide, which could be due to their high virulence and transmissibility induced by high genetic diversity. In this paper, we generated a single amino acid substitution FMDV variant with a high-fidelity polymerase associated with viral fitness, virulence, and transmissibility in a natural host. The results highlight that maintenance of viral population diversity is essential for interhost viral spread. This study provides evidence that higher genetic diversity of type O FMDV could increase both virulence and transmissibility, thus leading to their dominance in the global epidemic.


Asunto(s)
Virus de la Fiebre Aftosa/patogenicidad , Fiebre Aftosa/virología , ARN Polimerasa Dependiente del ARN/fisiología , Proteínas no Estructurales Virales/fisiología , Animales , Línea Celular , Cricetinae , Virus de la Fiebre Aftosa/enzimología , Virus de la Fiebre Aftosa/genética , Aptitud Genética , Variación Genética , Ratones , Mutación , Fenotipo , ARN Polimerasa Dependiente del ARN/genética , Porcinos , Proteínas no Estructurales Virales/genética , Virulencia
15.
J Virol ; 94(16)2020 07 30.
Artículo en Inglés | MEDLINE | ID: mdl-32493820

RESUMEN

Foot-and-mouth disease (FMD), which is caused by FMD virus (FMDV), remains a major plague among cloven-hoofed animals worldwide, and its outbreak often has disastrous socioeconomic consequences. A live-attenuated FMDV vaccine will greatly facilitate the global control and eradication of FMD, but a safe and effective attenuated FMDV vaccine has not yet been successfully developed. Here, we found that the internal ribosome entry site (IRES) element in the viral genome is a critical virulence determinant of FMDV, and a nucleotide substitution of cytosine (C) for guanine (G) at position 351 of the IRES endows FMDV with temperature-sensitive and attenuation (ts&att) phenotypes. Furthermore, we demonstrated that the C351G mutation of IRES causes a temperature-dependent translation defect by impairing its binding to cellular pyrimidine tract-binding protein (PTB), resulting in the ts&att phenotypes of FMDV. Natural hosts inoculated with viruses carrying the IRES C351G mutation showed no clinical signs, viremia, virus excretion, or viral transmission but still produced a potent neutralizing antibody response that provided complete protection. Importantly, the IRES C351G mutation is a universal determinant of the ts&att phenotypes of different FMDV strains, and the C351G mutant was incapable of reversion to virulence during in vitro and in vivo passages. Collectively, our findings suggested that manipulation of the IRES, especially its C351G mutation, may serve as a feasible strategy to develop live-attenuated FMDV vaccines.IMPORTANCE The World Organization for Animal Health has called for global control and eradication of foot-and-mouth disease (FMD), the most economically and socially devastating disease affecting animal husbandry worldwide. Live-attenuated vaccines are considered the most effective strategy for prevention, control, and eradication of infectious diseases due to their capacity to induce potent and long-lasting protective immunity. However, efforts to develop FMD virus (FMDV) live-attenuated vaccines have achieved only limited success. Here, by structure-function study of the FMDV internal ribosome entry site (IRES), we find that the C351 mutation of the IRES confers FMDV with an ideal temperature-sensitive attenuation phenotype by decreasing its interaction with cellular pyrimidine tract-binding protein (PTB) to cause IRES-mediated temperature-dependent translation defects. The temperature-sensitive attenuated strains generated by manipulation of the IRES address the challenges of FMDV attenuation differences among various livestock species and immunogenicity maintenance encountered previously, and this strategy can be applied to other viruses with an IRES to rationally design and develop live-attenuated vaccines.


Asunto(s)
Virus de la Fiebre Aftosa/genética , Sitios Internos de Entrada al Ribosoma/genética , Animales , Anticuerpos Neutralizantes/metabolismo , Bovinos , Femenino , Fiebre Aftosa/virología , Virus de la Fiebre Aftosa/metabolismo , Virus de la Fiebre Aftosa/patogenicidad , Regulación Viral de la Expresión Génica/genética , Sitios Internos de Entrada al Ribosoma/fisiología , Masculino , Ratones , Ratones Endogámicos BALB C , Mutación/genética , Ribosomas/genética , Porcinos , Vacunas Atenuadas , Virulencia/genética , Replicación Viral/genética
16.
Am J Pathol ; 190(12): 2464-2477, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33222991

RESUMEN

Heat shock proteins (HSPs) are emerging as valuable potential molecular targets in breast cancer therapy owing to their diverse functions in cancer cells. This study investigated the potential role of heat shock protein 27 (HSP27, also known as HSPB1) in breast cancer through heat shock protein B8 (HSPB8). The correlation between HSP27 and HSPB8 was identified by using co-immunoprecipitation, immunoprecipitation, and SUMOylation assays. Through gain- and loss-of-function approaches in MCF-7 cells, the effect of HSP27 on HSPB8 expression, SUMOylation level, and protein stability of HSPB8, as well as on cell proliferation, migration, and stemness, was elucidated. A mouse xenograft model of breast cancer cells was established to verify the function of HSP27 in vivo. Results indicate that HSP27 and HSPB8 were highly expressed in breast cancer tissues and MCF-7 cells. HSP27 was also found to induce the SUMOylation of HSPB8 at the 106 locus and subsequently increased its protein stability, which resulted in accelerated proliferation, migration, and stemness of breast cancer cells in vitro along with increased tumor metastasis of breast cancer in vivo. However, these results could be reversed by the knockdown of HSPB8. Overall, HSP27 induces SUMOylation of HSPB8 to promote HSPB8 expression, thereby endorsing proliferation and metastasis of breast cancer cells. This study may provide insight for the development of new targets for breast cancer.


Asunto(s)
Neoplasias de la Mama/patología , Progresión de la Enfermedad , Proteínas de Choque Térmico HSP27/metabolismo , Metástasis de la Neoplasia/patología , Animales , Neoplasias de la Mama/metabolismo , Proliferación Celular/fisiología , Femenino , Proteínas de Choque Térmico/genética , Humanos , Ratones , Proteínas Serina-Treonina Quinasas/metabolismo , Sumoilación/fisiología
17.
Opt Express ; 29(24): 40617-40632, 2021 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-34809397

RESUMEN

A new type of liquid crystal microlens array (LCMLA) constructed by a single-layered LC material is proposed. The basic dual-mode integrated LC microlens includes a concentric microhole electrode and a central plate electrode. Compared with traditional LC microlenses driven electrically, the dual-mode integrated LC microlens presents a better light control effect, such as being flexibly adjusted between the beam convergence and divergence modes, enlarging both the tunable range of the signal voltage and the focal length and also reducing the focal spot assisted by a convex electric-field generated by the central plate electrode, acquiring a sharper beam diverging microring formed by the concave LC microlens assisted by a concave electric-field generated by the microhole electrode. At the same time, we have also verified that the electric-field filling factor of the dual-mode integrated LCMLA can be obviously increased through jointly tuning the signal voltages applied independently over both the microhole electrode and the central plate electrode. This research has laid a solid foundation for continuously developing LCMLA technology.

18.
Opt Lett ; 46(14): 3388-3391, 2021 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-34264220

RESUMEN

As an optical-based classifier of the physical neural network, the independent diffractive deep neural network (D2NN) can be utilized to learn the single-view spatial featured mapping between the input lightfields and the truth labels by preprocessing a large number of training samples. However, it is still not enough to approach or even reach a satisfactory classification accuracy on three-dimensional (3D) targets owing to already losing lots of effective lightfield information on other view fields. This Letter presents a multiple-view D2NNs array (MDA) scheme that provides a significant inference improvement compared with individual D2NN or Res-D2NN by constructing a different complementary mechanism and then merging all base learners of distinct views on an electronic computer. Furthermore, a robust multiple-view D2NNs array (r-MDA) framework is demonstrated to resist the redundant spatial features of invalid lightfields due to severe optical disturbances.

19.
BMC Pediatr ; 21(1): 272, 2021 06 11.
Artículo en Inglés | MEDLINE | ID: mdl-34116676

RESUMEN

BACKGROUND: MYCN amplification and age are two critical prognostic factors of pediatric neuroblastoma. Previously, we had revealed the prognosis of MYCN target genes. However, the prognostic effects of age related genes in neuroblastoma are unclear. METHODS: The prognostic significance of age and MYCN amplification was determined through multivariate cox regression and Kaplan-Meier survival analysis. Genes differentially expressed in MYCN non-amplified younger neuroblastoma patients were identified using Therapeutically Applicable Research to Generate Effective Treatments (TARGET) and Gene Expression Omnibus (GEO) datasets. The prognostic effects of age related genes ALCAM, CACNA2D3, DST, EPB41L4A and KIF1B in pediatric neuroblastoma patients were determined by Kaplan-Meier survival. RESULTS: In a pediatric pan-cancer analysis, age was associated with the overall survival of pediatric B-lineage acute lymphoblastic leukemia, neuroblastoma and wilms tumor in TARGET dataset. Moreover, the prognostic effects of age in neuroblastoma were validated using two independent neuroblastoma cohorts. Furthermore, age and MYCN amplification were independent prognostic factors in pediatric neuroblastoma. Compared with MYCN non-amplified older neuroblastoma patients, MYCN non-amplified younger neuroblastoma patients had better clinical outcomes. ALCAM, CACNA2D3, DST, EPB41L4A and KIF1B were highly expressed in MYCN non-amplified younger neuroblastoma patients. And the higher expression levels of ALCAM, CACNA2D3, DST, EPB41L4A or KIF1B were associated with better prognosis of MYCN non-amplified neuroblastoma patients. DST was an independent prognostic factor in MYCN non-amplified neuroblastoma patients and MYCN non-amplified neuroblastoma younger patients with higher DST expression levels had the best clinical overall survival. CONCLUSIONS: Age related gene DST was an independent prognostic factor in MYCN non-amplified neuroblastoma. MYCN non-amplified younger neuroblastoma patients with higher DST expression levels had the best clinical overall survival.


Asunto(s)
Distonina/genética , Amplificación de Genes , Neuroblastoma , Niño , Expresión Génica , Humanos , Proteína Proto-Oncogénica N-Myc/genética , Proteína Proto-Oncogénica N-Myc/metabolismo , Neuroblastoma/genética , Pronóstico
20.
J Clin Lab Anal ; 35(9): e23945, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34398996

RESUMEN

BACKGROUND: MicroRNAs (miRNAs) participate in the reactivation of γ-globin expression in ß-thalassemia. However, the miRNA transcriptional profiles of pediatric ß-thalassemia remain unclear. Accordingly, in this study, we assessed miRNA expression in pediatric patients with ß-thalassemia. METHODS: Differentially expressed miRNAs in pediatric patients with ß-thalassemia were determined using microRNA sequencing. RESULTS: Hsa-miR-483-3p, hsa-let-7f-1-3p, hsa-let-7a-3p, hsa-miR-543, hsa-miR-433-3p, hsa-miR-4435, hsa-miR-329-3p, hsa-miR-92b-5p, hsa-miR-6747-3p and hsa-miR-495-3p were significantly upregulated, whereas hsa-miR-4508, hsa-miR-20a-5p, hsa-let-7b-5p, hsa-miR-93-5p, hsa-let-7i-5p, hsa-miR-6501-5p, hsa-miR-221-3p, hsa-let-7g-5p, hsa-miR-106a-5p, and hsa-miR-17-5p were significantly downregulated in pediatric patients with ß-thalassemia. After integrating our data with a previously published dataset, we found that hsa-let-7b-5p and hsa-let-7i-5p expression levels were also lower in adolescent or adult patients with ß-thalassemia. The predicted target genes of hsa-let-7b-5p and hsa-let-7i-5p were associated with the transforming growth factor ß receptor, phosphatidylinositol 3-kinase/AKT, FoxO, Hippo, and mitogen-activated protein kinase signaling pathways. We also identified 12 target genes of hsa-let-7a-3p and hsa-let-7f-1-3p and 21 target genes of hsa-let-7a-3p and hsa-let-7f-1-3p, which were differentially expressed in patients with ß-thalassemia. Finally, we found that hsa-miR-190-5p and hsa-miR-1278-5p may regulate hemoglobin switching by modulation of the B-cell lymphoma/leukemia 11A gene. CONCLUSION: The results of the study show that several microRNAs are dysregulated in pediatric ß-thalassemia. Further, the results also indicate toward a critical role of let7 miRNAs in the pathogenesis of pediatric ß-thalassemia, which needs to be investigated further.


Asunto(s)
Regulación de la Expresión Génica , Redes Reguladoras de Genes , MicroARNs/genética , Talasemia beta/genética , Talasemia beta/patología , Estudios de Casos y Controles , Preescolar , Femenino , Perfilación de la Expresión Génica , Humanos , Masculino , Pronóstico
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