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1.
J Virol ; 96(14): e0080622, 2022 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-35862697

RESUMO

Baculoviruses initiate oral infection in the highly alkaline midgut of insects via a group of envelope proteins called per os infectivity factors (PIFs). To date, no high-resolution structural information has been reported for any PIF. Here, we present the crystal structure of the PIF5 ectodomain (PIF5e) from Autographa californica multiple nucleopolyhedrovirus (AcMNPV) at a 2.2-Å resolution. It revealed an open cavity between the N-terminal E1 domain and the C-terminal E2 domain and a cysteine-rich region with three pairs of disulfide bonds in the E2 domain. Multiple conserved intramolecular interactions within PIF5 are essential for maintaining its tertiary structure. Two conserved arginines (Arg8 and Arg74) play critical roles in E1-E2 interactions, and mutagenesis analysis supported their crucial role in oral infection. Importantly, the reduction in the oral infectivity of the Arg8, Arg74, or cysteine mutant viruses was related to the proteolytic cleavage of PIF5 by the endogenous protease embedded in occlusion bodies during alkaline treatment. This suggested that the structural stability of PIF5 under physiological conditions in the insect midgut is critical for baculoviral oral infectivity. IMPORTANCE Per os infection mediated by PIFs is the highly complex mechanism by which baculoviruses initiate infection in insects. Previous studies revealed that multiple PIF proteins form a large PIF complex on the envelope of virions, while PIF5 functions independently of the PIF complex. Here, we report the crystal structure of AcMNPV PIF5e, which, to our knowledge, is the first atomic structure reported for a PIF protein. The structure revealed the precise locations of three previously proposed disulfide bonds and other conserved intramolecular interactions, which are important for the structural stability of PIF5 and are also essential for oral infectivity. These findings advance our understanding of the molecular mechanism of baculovirus oral infection under alkaline conditions.


Assuntos
Nucleopoliedrovírus , Proteínas do Envelope Viral , Animais , Cisteína/química , Dissulfetos/química , Insetos , Nucleopoliedrovírus/química , Nucleopoliedrovírus/genética , Conformação Proteica , Spodoptera , Proteínas do Envelope Viral/química , Proteínas do Envelope Viral/genética
2.
Mol Biol Rep ; 2022 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-35752700

RESUMO

BACKGROUND: Altered phenotype of Fibroblast-like synoviocyte(FLS) is an important cause of the pathogenesis and progression of rheumatoid arthritis(RA), but the specific mechanism causing this change has not yet been fully explained. The exact mechanism by which the biological properties of FLS change in RA is still unclear. microRNAs (miRNAs) have been shown to affect changes in the biological properties of RA-FLS, but the critical miRNAs remain to be discovered. Thus, we first used miRNA microarray and WGCNA to confirm the RA-FLS miRNA landscape and establish their biological functions via network analyses at the system level, as well as to provide a platform for modulating the overall phenotypic effects of RA-FLS. METHODS: We enrolled a total of 3 patients with RA and 3 healthy participants, constructed a network analysis of via miRNA microarray and RNA-sequencing. Furthermore, the coexpression analyses of miR-7 and ciRS-7 were verified by siRNA transfection, overexpression and qPCR analyses. Finally, we evaluated the effects of adjusting the expression levels of miR-7 and ciRS-7 on RA-FLS, respectively. RESULTS: We identified distinct miRNA features in RA-FLS, including miR-7, which was significantly lower expressed. Furthermore, we discovered the negative regulatory relationship between ciRS-7 and miR-7 in RA-FLS. Finally, we overexpressed miR-7 in RA-FLS and discovered that miR-7 inhibited RA-FLS hyperproliferation, migration, invasion, and apoptosis, whereas ciRS-7 overexpression reversed these effects. CONCLUSIONS: The results indicate that the dysregulation of miR-7 in FLS may be involved in the pathological processes of RA and that ciRS-7 induced the suppression of tumor-like biological characters of RA-FLS via modulation of miR-7. These findings help us understand the essential roles of a regulatory interaction between ciRS-7 and miR-7 mediating disease activity of RA, and will facilitate to develop potential intervention target for RA.

3.
Viruses ; 14(6)2022 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-35746591

RESUMO

Bombyx mori nucleopolyhedrovirus (BmNPV) is a pathogen that causes severe disease in silkworms. In a previous study, we demonstrated that by using the CRISPR/Cas9 system to disrupt the BmNPV ie-1 and me53 genes, transgenic silkworms showed resistance to BmNPV infection. Here, we used the same strategy to simultaneously target lef8 and lef9, which are essential for BmNPV replication. A PCR assay confirmed that double-stranded breaks were induced in viral DNA at targeted sequences in BmNPV-infected transgenic silkworms that expressed small guide RNAs (sgRNAs) and Cas9. Bioassays and qPCR showed that replication of BmNPV and mortality were significantly reduced in the transgenic silkworms in comparison with the control groups. Microscopy showed degradation of midgut cells in the BmNPV-infected wild type silkworms, but not in the transgenic silkworms. These results demonstrated that transgenic silkworms using the CRISPR/Cas9 system to disrupt BmNPV lef8 and lef9 genes could successfully prevent BmNPV infection. Our research not only provides more alternative targets for the CRISPR antiviral system, but also aims to provide new ideas for the application of virus infection research and the control of insect pests.


Assuntos
Bombyx , Nucleopoliedrovírus , Animais , Animais Geneticamente Modificados , Sistemas CRISPR-Cas , Nucleopoliedrovírus/genética
4.
PLoS Genet ; 18(6): e1009806, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35666722

RESUMO

Mutation rates are of key importance for understanding evolutionary processes and predicting their outcomes. Empirical mutation rate estimates are available for a number of RNA viruses, but few are available for DNA viruses, which tend to have larger genomes. Whilst some viruses have very high mutation rates, lower mutation rates are expected for viruses with large genomes to ensure genome integrity. Alphabaculoviruses are insect viruses with large genomes and often have high levels of polymorphism, suggesting high mutation rates despite evidence of proofreading activity by the replication machinery. Here, we report an empirical estimate of the mutation rate per base per strand copying (s/n/r) of Autographa californica multiple nucleopolyhedrovirus (AcMNPV). To avoid biases due to selection, we analyzed mutations that occurred in a stable, non-functional genomic insert after five serial passages in Spodoptera exigua larvae. Our results highlight that viral demography and the stringency of mutation calling affect mutation rate estimates, and that using a population genetic simulation model to make inferences can mitigate the impact of these processes on estimates of mutation rate. We estimated a mutation rate of µ = 1×10-7 s/n/r when applying the most stringent criteria for mutation calling, and estimates of up to µ = 5×10-7 s/n/r when relaxing these criteria. The rates at which different classes of mutations accumulate provide good evidence for neutrality of mutations occurring within the inserted region. We therefore present a robust approach for mutation rate estimation for viruses with stable genomes, and strong evidence of a much lower alphabaculovirus mutation rate than supposed based on the high levels of polymorphism observed.


Assuntos
Nucleopoliedrovírus , Animais , Mutação , Taxa de Mutação , Nucleopoliedrovírus/genética , Spodoptera
5.
Insect Biochem Mol Biol ; 147: 103775, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35504546

RESUMO

Melanization is a key immune response mediated by serine protease (SP) cascade in insects. Multiple SP pathways exist in different species and it is unclear how conserved these cascades are. The cotton bollworm Helicoverpa armigera is a major worldwide agricultural pest. We reported a conserved melanization pathway in this species, which consists of SP41, cSP1, and cSP6. In this study, we attempted to identify an insect pathogen that elicits the cascade and test whether or not there are other SP cascades in H. armigera. After Micrococcus luteus, Enterobacter cloacae, Beauveria bassiana, or Helicoverpa armigera nucleopolyhedrovirus were injected into larvae, pathogen-induced hemolymph samples were collected for in vitro biochemical assays, which failed to detect proSP41 or procSP1 activation. In contrast, we found that procSP4, a protein proposed to participate in H. armigera melanization, was activated in M. luteus infected hemolymph. We further revealed that cSP8 was a prophenoloxidase (PPO) activating protease downstream of cSP4, and cSP4 was activated by cSP10. The pathway of cSP10-cSP4-cSP8 activated PPO in vitro. Efficiently cleaved procSPH11 and procSPH50 by cSP8 substantially enhanced phenoloxidase activity, suggesting they work together as a cofactor for cSP8 mediated PPO activation. Hemolymph from larvae challenged with M. luteus or its peptidoglycan effectively activated procSP10. Collectively, these results revealed a new PPO activation cascade specifically triggered by the bacterium. In addition, we found that the PPO activation cascades in H. armigera and Manduca sexta are conserved.

6.
Virol Sin ; 2022 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-35527222

RESUMO

Apis mellifera filamentous virus (AmFV) is a large DNA virus that is endemic in honeybee colonies. The genome sequence of the AmFV Swiss isolate (AmFV CH-C05) has been reported, but so far very few molecular studies have been conducted on this virus. In this study, we isolated and purified AmFV (AmFV CN) from Chinese honeybee (Apis mellifera) colonies and elucidated its genomics and proteomics. Electron microscopy showed ovoid purified virions with dimensions of 300-500 â€‹× â€‹210-285 â€‹nm, wrapping a 3165 â€‹× â€‹40 â€‹nm filamentous nucleocapsid in three figure-eight loops. Unlike AmFV CH-C05, which was reported to have a circular genome, our data suggest that AmFV CN has a linear genome of approximately 493 â€‹kb. A total of 197 ORFs were identified, among which 36 putative genes including 18 baculoviral homologs were annotated. The overall nucleotide similarity between the CN and CH-C05 isolates was 96.9%. Several ORFs were newly annotated in AmFV CN, including homologs of per os infectivity factor 4 (PIF4) and a putative integrase. Phylogenomic analysis placed AmFVs on a separate branch within the newly proposed virus class Naldaviricetes. Proteomic analysis revealed 47 AmFV virion-associated proteins, of which 14 had over 50% sequence coverage, suggesting that they are likely to be main structural proteins. In addition, all six of the annotated PIFs (PIF-0-5) were identified by proteomics, suggesting that they may function as entry factors in AmFV infection. This study provides fundamental information regarding the molecular biology of AmFV.

7.
BMC Neurol ; 22(1): 196, 2022 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-35624413

RESUMO

BACKGROUND: Convulsive status epilepticus (CSE) is a common neurologic emergency with high morbidity and mortality. This single center study is aimed to assess changes of serum biochemical biomarkers after seizure, and their associations with the development of CSE. METHODS: From January 2015 to October 2016, a total of 57 CSE patients, and 30 healthy controls without central nervous system diseases were enrolled in Children's Hospital of Soochow University. CSE patients were further divided into viral encephalitis (VEN, 13 cases), primary generalized epilepsy (PGE, 30 cases), and complex febrile seizures (CFS, 14 cases). The levels of serum biochemical biomarkers were measured using the corresponding commercial ELISA kits. Logistic regression analysis was performed to identify the associations between these biomarkers and diseases. RESULTS: At the 1st and 4th day of CSE, neuron-specific enolase (NSE; 1st day: 20.553 ± 5.360, 4th day: 10.094 ± 3.426) and vascular endothelial growth factor (VEGF; 1st day: 153.504 ± 31.246, 4th day: 138.536 ± 25.221) in the CSE group were increased compared to the control (NSE: 6.138 ± 1.941; VEGF: 119.210 ± 31.681). Both the levels of S-100 calcium binding protein B (S-100B; 1st day: 0.738 ± 0.391) and C-reactive protein (CRP; 1st day: 11.128 ± 12.066) were elevated at 1st day of CSE (S-100B: 0.387 ± 0.040; CRP: 3.915 ± 2.064). For glial fibrillary acidic protein (GFAP), it was remarkably upregulated at 4th day of CSE (3.998 ± 1.211). NSE (P = 0.000), S-100B (P = 0.000), CRP (P = 0.011), and VEGF (P = 0.000) at 1st day of CSE, and NSE (P = 0.000), VEGF (P = 0.005), and GFAP (P = 0.000) at 4th day of CSE were significantly associated with the occurrence of CSE. Besides, NSE (P = 0.002), S-100B (P = 0.001), and VEGF (P = 0.002) at 4th day of CSE were significantly associated with VEN. CONCLUSIONS: The levels of serum NSE, S-100B, CRP, VEGF, and GFAP are associated with CSE.


Assuntos
Doenças do Sistema Nervoso Central , Estado Epiléptico , Biomarcadores , Proteína C-Reativa , Criança , Humanos , Estudos Prospectivos , Fator A de Crescimento do Endotélio Vascular
8.
Signal Transduct Target Ther ; 7(1): 122, 2022 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-35418165

RESUMO

The cell identity of malignant cells and how they acquire it are fundamental for our understanding of cancer. Here, we report that esophageal squamous cell carcinoma (ESCC) cells display molecular features equally similar but distinct to all three types of normal esophageal epithelial cells, which we term as confused cell identity (CCI). CCI is an independent prognostic marker associated with poor prognosis in ESCC. Further, we identify tropomyosin 4 (TPM4) as a critical CCI gene that promotes the aggressiveness of ESCC in vitro and in vivo. And TPM4 creates CCI through activating the Jak/STAT-SOX2 pathway. Thus, our study suggests an unrecognized feature of ESCC cells, which might be of value for clinic prognosis and potential interference.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Linhagem Celular Tumoral , Neoplasias Esofágicas/metabolismo , Carcinoma de Células Escamosas do Esôfago/genética , Humanos
9.
Adv Sci (Weinh) ; 9(14): e2104333, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35403837

RESUMO

Coronavirus disease 2019 (COVID-19) remains a global public health threat. Hence, more effective and specific antivirals are urgently needed. Here, COVID-19 hyperimmune globulin (COVID-HIG), a passive immunotherapy, is prepared from the plasma of healthy donors vaccinated with BBIBP-CorV (Sinopharm COVID-19 vaccine). COVID-HIG shows high-affinity binding to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike (S) protein, the receptor-binding domain (RBD), the N-terminal domain of the S protein, and the nucleocapsid protein; and blocks RBD binding to human angiotensin-converting enzyme 2 (hACE2). Pseudotyped and authentic virus-based assays show that COVID-HIG displays broad-spectrum neutralization effects on a wide variety of SARS-CoV-2 variants, including D614G, Alpha (B.1.1.7), Beta (B.1.351), Gamma (P.1), Kappa (B.1.617.1), Delta (B.1.617.2), and Omicron (B.1.1.529) in vitro. However, a significant reduction in the neutralization titer is detected against Beta, Delta, and Omicron variants. Additionally, assessments of the prophylactic and treatment efficacy of COVID-HIG in an Adv5-hACE2-transduced IFNAR-/- mouse model of SARS-CoV-2 infection show significantly reduced weight loss, lung viral loads, and lung pathological injury. Moreover, COVID-HIG exhibits neutralization potency similar to that of anti-SARS-CoV-2 hyperimmune globulin from pooled convalescent plasma. Overall, the results demonstrate the potential of COVID-HIG against SARS-CoV-2 infection and provide reference for subsequent clinical trials.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Globulinas , Animais , COVID-19/terapia , Globulinas/uso terapêutico , Humanos , Imunização Passiva , Camundongos , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus
10.
Nat Cancer ; 3(6): 753-767, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35449309

RESUMO

Small cell lung cancer (SCLC) is notorious for its early and frequent metastases, which contribute to it as a recalcitrant malignancy. To understand the molecular mechanisms underlying SCLC metastasis, we generated SCLC mouse models with orthotopically transplanted genome-edited lung organoids and performed multiomics analyses. We found that a deficiency of KMT2C, a histone H3 lysine 4 methyltransferase frequently mutated in extensive-stage SCLC, promoted multiple-organ metastases in mice. Metastatic and KMT2C-deficient SCLC displayed both histone and DNA hypomethylation. Mechanistically, KMT2C directly regulated the expression of DNMT3A, a de novo DNA methyltransferase, through histone methylation. Forced DNMT3A expression restrained metastasis of KMT2C-deficient SCLC through repressing metastasis-promoting MEIS/HOX genes. Further, S-(5'-adenosyl)-L-methionine, the common cofactor of histone and DNA methyltransferases, inhibited SCLC metastasis. Thus, our study revealed a concerted epigenetic reprogramming of KMT2C- and DNMT3A-mediated histone and DNA hypomethylation underlying SCLC metastasis, which suggested a potential epigenetic therapeutic vulnerability.


Assuntos
DNA Metiltransferase 3A , Histona-Lisina N-Metiltransferase , Neoplasias Pulmonares , Carcinoma de Pequenas Células do Pulmão , Animais , DNA/metabolismo , DNA (Citosina-5-)-Metiltransferases/genética , Metilação de DNA/genética , DNA Metiltransferase 3A/genética , Metilases de Modificação do DNA/genética , Epigênese Genética/genética , Histona-Lisina N-Metiltransferase/deficiência , Histona-Lisina N-Metiltransferase/genética , Histonas/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Metiltransferases/genética , Camundongos , Carcinoma de Pequenas Células do Pulmão/genética , Carcinoma de Pequenas Células do Pulmão/secundário
11.
Antiviral Res ; 199: 105273, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35257725

RESUMO

Crimean-Congo hemorrhagic fever virus (CCHFV) is a highly pathogenic tick-borne virus that causes fever, hemorrhage, and multi-organ failure, with an average fatality rate of ∼40% in humans. Currently, there are no available vaccines or drugs for the treatment of Crimean-Congo hemorrhagic fever (CCHF). Favipiravir (T-705), a nucleoside analog, protects against CCHFV infection in animal models. Here, we evaluated the anti-CCHFV efficacy of several nucleoside analogs, including some well-known compounds such as remdesivir (GS-5734), EIDD-1931 and its prodrug molnupiravir (EIDD-2801), as well as a novel T-705-derived compound H44. T-705, H44, and EIDD-1931 inhibited CCHFV infection in vitro while GS-5734 had no inhibitory effect. All three nucleoside analogs functioned at the "post-entry" stage of virus infection. However, EIDD-2801 failed to protect type I interferon receptor knockout (IFNAR)-/- mice from CCHFV infection. H44, similar to T-705, conferred 100% protection to IFNAR-/- mice against lethal CCHFV challenge, even with delayed administration. This study provided in vitro and in vivo data regarding the anti-CCHFV efficacy of different nucleosides and identified a novel compound, H44, as a promising drug candidate for the treatment of CCHFV infection in vivo.


Assuntos
Vírus da Febre Hemorrágica da Crimeia-Congo , Febre Hemorrágica da Crimeia , Animais , Modelos Animais de Doenças , Febre Hemorrágica da Crimeia/tratamento farmacológico , Febre Hemorrágica da Crimeia/prevenção & controle , Camundongos , Nucleosídeos/farmacologia , Nucleosídeos/uso terapêutico
12.
Front Immunol ; 13: 793855, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35350778

RESUMO

Rheumatoid arthritis (RA) is an autoimmune disease characterized by chronic inflammatory in joints. Invasive pannus is a characteristic pathological feature of RA. RA fibroblast-like synoviocytes (FLSs) are showed tumor-like biological characters that facilitate pannus generation. Importantly, it has been documented that extracellular vesicle (EVs) derived microRNAs have a vital role of angiogenesis in various immune inflammatory diseases. However, whether RA FLSs derived EVs can facilitate angiogenesis and the underlying mechanism is undefined. Herein, we aim to investigate the key role of RA FLSs derived EVs on angiogenesis in endothelial cells (ECs). We indicate that RA FLSs derived EVs promote ECs angiogenesis by enhancing migration and tube formation of ECs in vitro. Also, we confirm that RA FLSs derived EVs can significantly facilitate ECs angiogenesis with a matrigel angiogenesis mice model. In terms of the mechanisms, both RNAs and proteins in EVs play roles in promoting ECs angiogenesis, but the RNA parts are more fundamental in this process. By combining microRNA sequencing and qPCR results, miR-1972 is identified to facilitate ECs angiogenesis. The blockage of miR-1972 significantly abrogated the angiogenesis stimulative ability of RA FLSs derived EVs in ECs, while the overexpression of miR-1972 reversed the effect in ECs. Specifically, the p53 level is decreased, and the phosphorylated mTOR is upregulated in miR-1972 overexpressed ECs, indicating that miR-1972 expedites angiogenesis through p53/mTOR pathway. Collectively, RA FLSs derived EVs can promote ECs angiogenesis via miR-1972 targeted p53/mTOR signaling, targeting on RA FLSs derived EVs or miR-1972 provides a promising strategy for the treatment of patients with RA.


Assuntos
Artrite Reumatoide , Vesículas Extracelulares , MicroRNAs , Sinoviócitos , Animais , Artrite Reumatoide/metabolismo , Proliferação de Células/genética , Células Cultivadas , Células Endoteliais/metabolismo , Vesículas Extracelulares/metabolismo , Fibroblastos/metabolismo , Humanos , Camundongos , MicroRNAs/genética , MicroRNAs/metabolismo , Sinoviócitos/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
13.
J Virol ; 96(7): e0217321, 2022 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-35266805

RESUMO

The Bunyavirales contain many important human pathogens that lack an antiviral therapy. The cap-snatching endonuclease (EN) of segmented negative-strand RNA viruses is an attractive target for broad-spectrum antivirals due to its essential role in initiating viral transcription. L-742,001, a previously reported diketo acid inhibitor against influenza virus EN, demonstrated potent EN inhibition and antiviral activity on various bunyaviruses. However, the precise inhibitory mechanism of the compound is still poorly understood. We recently characterized a highly active EN from Ebinur Lake virus (EBIV), a newly identified member of the Orthobunyavirus genus, and obtained its high-resolution structures, paving the way for structure-guided inhibitor development. Here, nine L-742,001 derivatives were designed and synthesized de novo, and their structure-activity relationship with EBIV EN was studied. In vitro biochemical data showed that the compounds inhibited the EBIV EN activity with different levels and could be divided into three categories. Five representative compounds were selected for further cell-based antiviral assay, and the results largely agreed with those of the EN assays. Furthermore, the precise binding modes of L-742,001 and its derivatives in EN were revealed by determining the high-resolution crystal structures of EN-inhibitor complexes, which suggested that the p-chlorobenzene is essential for the inhibitory activity and the flexible phenyl has the greatest exploration potential. This study provides an important basis for the structure-based design and optimization of inhibitors targeting EN of segmented negative-strand RNA viruses. IMPORTANCE The Bunyavirales contain many important human pathogens such as Crimean-Congo hemorrhagic fever virus and Lassa virus that pose serious threats to public health; however, currently there are no specific antiviral drugs against these viruses. The diketo acid inhibitor L-742,001 is a potential drug as it inactivates the cap-snatching endonuclease (EN) encoded by bunyaviruses. Here, we designed and synthesized nine L-742,001 derivatives and assessed the structure-activity relationship using EN of the newly identified Ebinur Lake virus (EBIV) as a research model. Our results revealed that the p-chlorobenzene of this broad-spectrum EN inhibitor is crucial for the inhibitory activity and the flexible phenyl "arm" has the best potential for further optimization. As cap-snatching ENs are present not only in bunyaviruses but also in influenza viruses, our data provide important guidelines for the development of novel and more potent diketo acid-based antiviral drugs against those viruses.


Assuntos
Antivirais , Bunyaviridae , Endonucleases , Proteínas Virais , Antivirais/síntese química , Antivirais/farmacologia , Antivirais/uso terapêutico , Bunyaviridae/enzimologia , Infecções por Bunyaviridae/tratamento farmacológico , Infecções por Bunyaviridae/virologia , Endonucleases/metabolismo , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Humanos , Hidroxibutiratos/química , Hidroxibutiratos/farmacologia , Hidroxibutiratos/uso terapêutico , Piperidinas/química , Piperidinas/farmacologia , Piperidinas/uso terapêutico , Relação Estrutura-Atividade , Proteínas Virais/metabolismo
14.
Dis Markers ; 2022: 7758735, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35308139

RESUMO

Objectives: To discover a more powerful diagnostic tool for the detection of hepatocellular carcinoma (HCC). Methods: 16 extracellularly located candidates were selected by analyzing the expression array datasets in GEO. 10 of them were validated in clinical samples by ELISA. Differences of each variable were compared by one-way ANOVA or Kruskal-Wallis test. CCL20 and LCN2 were determined in all samples (HCC, 167; liver cirrhosis, 106; and healthy control, 106) and finally chosen for the construction of the combination model by binary logistic regression. The models were first built using a comprehensive control, including both liver cirrhosis (LC) and healthy donors. Then, the models were rebuilt by using the LC group alone as a control. ROC analysis was performed to compare the diagnostic efficiency of each indicator. Results: Levels of CCL20 and LCN2 in HCC sera were significantly higher than those in all controls. Using the comprehensive control, ROC curves showed that the optimum diagnostic cutoff of the CCL20 and LCN2 combination was 0.443 (area under curve (AUC) of 0.927 (95% CI 0.896-0.951), sensitivity of 0.808, specificity of 0.892, and accuracy of 0.859). For detection of HCC from LC control, the optimum diagnostic cutoff was 0.590 (AUC of 0.919 (95% CI 0.880-0.948), sensitivity of 0.814, specificity of 0.868, and accuracy of 0.834). Furthermore, the model maintained diagnostic accuracy for patients with HCC in the early stage, with the sensitivity and specificity of 0.75 and 0.77 from LC control, yet the AFP only reached 0.5 and 0.67, respectively. Conclusion: A combination model composed of CCL20 and LCN2 may serve as a more efficient tool for distinguishing HCC from nonmalignant liver diseases.


Assuntos
Biomarcadores Tumorais/sangue , Carcinoma Hepatocelular/diagnóstico , Quimiocina CCL20/sangue , Lipocalina-2/sangue , Neoplasias Hepáticas/diagnóstico , Bases de Dados Genéticas , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Cirrose Hepática/sangue , Cirrose Hepática/complicações , Masculino , Pessoa de Meia-Idade , Transcriptoma
15.
Neurosci Bull ; 38(7): 809-819, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35149974

RESUMO

Alzheimer's disease (AD) is the most prevalent neurodegenerative disease featuring progressive cognitive impairment. Although the etiology of late-onset AD remains unclear, the close association of AD with apolipoprotein E (APOE), a gene that mainly regulates lipid metabolism, has been firmly established and may shed light on the exploration of AD pathogenesis and therapy. However, various confounding factors interfere with the APOE-related AD risk, raising questions about our comprehension of the clinical findings concerning APOE. In this review, we summarize the most debated factors interacting with the APOE genotype and AD pathogenesis, depict the extent to which these factors relate to APOE-dependent AD risk, and discuss the possible underlying mechanisms.


Assuntos
Doença de Alzheimer , Doenças Neurodegenerativas , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Apolipoproteína E4/genética , Apolipoproteínas E/genética , Genótipo , Humanos , Metabolismo dos Lipídeos , Fatores de Risco
16.
J Am Chem Soc ; 144(13): 5702-5707, 2022 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-35212528

RESUMO

The rapid emergence and spread of escaping mutations of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has significantly challenged our efforts in fighting against the COVID-19 pandemic. A broadly neutralizing reagent against these concerning variants is thus highly desirable for the prophylactic and therapeutic treatments of SARS-CoV-2 infection. We herein report a covalent engineering strategy on protein minibinders for potent neutralization of the escaping variants such as B.1.617.2 (Delta), B.1.617.1 (Kappa), and B.1.1.529 (Omicron) through in situ cross-linking with the spike receptor binding domain (RBD). The resulting covalent minibinder (GlueBinder) exhibited enhanced blockage of RBD-human angiotensin-converting enzyme 2 (huACE2) interaction and more potent neutralization effect against the Delta variant than its noncovalent counterpart as demonstrated on authentic virus. By leveraging the covalent chemistry against escaping mutations, our strategy may be generally applicable for restoring and enhancing the potency of neutralizing antibodies to SARS-CoV-2 and other rapidly evolving viral targets.


Assuntos
COVID-19 , SARS-CoV-2 , Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19/tratamento farmacológico , Humanos , Testes de Neutralização , Pandemias , Ligação Proteica , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genética
17.
J Virol ; 96(6): e0208521, 2022 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-35044209

RESUMO

The cap-snatching endonuclease (EN) of segmented negative-strand RNA viruses (sNSVs) produces short capped primers for viral transcription by cleaving the host mRNAs. EN requires divalent metals as cofactors for nucleic acid substrates cleavage; however, the detailed mechanism of metal ion-dependent catalysis of ENs remains obscure. In this work, we reported the EN crystal structure of the Ebinur Lake virus (EBIV), an emerging mosquito-borne orthobunyavirus, and investigated its enzymatic properties and metal ion-based catalytic mechanism. In vitro biochemical data showed that EBIV EN is a specific RNA nuclease and prefers to cleave unstructured uridine-rich ssRNA. Structural comparison indicated that the overall structural architecture of EBIV EN is similar to that of other sNSV ENs, while the detailed active site configuration including the binding state of metal ions and the conformation of the LA/LB loop pair is different. Based on sequence conservation analysis, nine active site mutants were constructed, and seven crystal structures of them were determined. Mutations of active site residues associated with the two metal ions (Mn1 and Mn2) coordination abolished EN activity. Crystallographic analyses further revealed that none of these mutants bound two metal ions simultaneously in the active site. Importantly, we found that the perturbation of Mn1-coordination (metal site 1), resulted in the enhancement or elimination of Mn2-coordination (metal site 2). Taken together, our data provide structural evidence to support the two-metal-ion catalytic mechanism of EBIV EN and the correlation of metal binding at the two binding sites, which may be commonly shared by bunyaviruses or other sNSVs. IMPORTANCE The viral endonucleases (ENs) encoded by bunyaviruses and orthomyxoviruses play an essential role in initiating transcription by "snatching" capped primers from the host mRNAs. These ENs are metal-ion-dependent nucleases; however, the details of their catalytic mechanism remain elusive. Here, we reported high-resolution crystal structures of the wild-type and mutant ENs of a novel bunyavirus, the Ebinur Lake virus (EBIV), and revealed the structure and function relationship of EN. The EBIV EN exhibited differences in the details of active site structure compared to its homologues. Our data provided structural evidence to support a two-metal-ion catalytic mechanism of EBIV EN, and found the correlation of metal binding at both binding sites, which might reflect the dynamic structural properties that correlate to EN catalytic function. Taken together, our results revealed the structural characteristics of EBIV EN and made important implications for understanding the catalytic mechanism of cap-snatching ENs.


Assuntos
Endonucleases , Orthobunyavirus , Proteínas Virais , Animais , Catálise , Endonucleases/química , Endonucleases/genética , Endonucleases/metabolismo , Ativação Enzimática/genética , Mutação , Orthobunyavirus/enzimologia , Orthobunyavirus/genética , Capuzes de RNA/metabolismo , RNA Mensageiro/metabolismo , Proteínas Virais/genética , Proteínas Virais/metabolismo
18.
J Leukoc Biol ; 111(3): 641-653, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34254354

RESUMO

Fibroblast-like synoviocytes (FLSs) are the predominant effector cells in the pathological progression of rheumatoid arthritis (RA). Therefore, elucidating the underlying molecular mechanism of the biologic behaviors in RA-FLSs will be helpful in developing the potent targets for the treatment of RA. We have previously documented that the tumor-like biologic behaviors of RA-FLSs are exacerbated by urokinase-type plasminogen activator receptor (uPAR), a specifically up-regulated receptor in RA-FLSs. Here, we investigate the further mechanism of uPAR and clarify its function in RA-FLSs. We demonstrate that miR-221-3p positively correlates to uPAR and regulates uPAR level in RA-FLSs. Simultaneously, one long noncoding RNA, nuclear paraspeckle assembly transcript 1_1 (NEAT1_1) is identified, which can predictively target miR-221-3p at three sites, indicating a strong possibility of being a competing endogenous RNA in RA-FLSs. Interestingly, NEAT1_1 and miR-221-3p can colocate in the nucleus and cytoplasm in RA-FLSs. Importantly, NEAT1_1 can act as a rheostat for the miR-221-3p/uPAR axis and the downstream JAK signaling. In line with the biologic function, NEAT1_1 negatively regulates the tumor-like characters, and cytokine secretions of RA-FLSs. Collectively, our data provide new insight into the mechanisms of NEAT1_1 in modulating RA-FLSs tumor-like behaviors. The targeting of NEAT1_1 and miR-221-3p/uPAR axis may have a promising therapeutic role in patients with RA.

19.
Adv Sci (Weinh) ; 9(7): e2104192, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34971128

RESUMO

Coronavirus disease 2019 (COVID-19) patients with impact on skin and hair loss are reported. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is detected in the skin of some patients; however, the detailed pathological features of skin tissues from patients infected with SARS-CoV-2 at a molecular level are limited. Especially, the ability of SARS-CoV-2 to infect skin cells and impact their function is not well understood. A proteome map of COVID-19 skin is established here and the susceptibility of human-induced pluripotent stem cell (hiPSC)-derived skin organoids with hair follicles and nervous system is investigated, to SARS-CoV-2 infection. It is shown that KRT17+ hair follicles can be infected by SARS-CoV-2 and are associated with the impaired development of hair follicles and epidermis. Different types of nervous system cells are also found to be infected, which can lead to neuron death. Findings from the present work provide evidence for the association between COVID-19 and hair loss. hiPSC-derived skin organoids are also presented as an experimental model which can be used to investigate the susceptibility of skin cells to SARS-CoV-2 infection and can help identify various pathological mechanisms and drug screening strategies.


Assuntos
COVID-19/fisiopatologia , Células-Tronco Pluripotentes Induzidas/citologia , Modelos Biológicos , Organoides/citologia , Pele/citologia , COVID-19/virologia , Folículo Piloso/virologia , Humanos , Sistema Nervoso/virologia , Proteômica , SARS-CoV-2/isolamento & purificação
20.
ACS Synth Biol ; 11(1): 144-153, 2022 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-34933547

RESUMO

The engineering of viral genomes facilitates both fundamental and applied research on viruses. However, the multiloci manipulation of DNAs of viruses with large DNA genomes, such as baculoviruses, herpesviruses, and poxviruses, is technically challenging, particularly for highly homologous or repetitive sequences. Homologous regions (hrs) have multiple copies in many large DNA viruses and play pivotal roles in the viral life cycle. Here, we used synthetic biology to investigate the fundamental function of baculoviral hrs by conducting multiloci manipulation of Autographa californica multiple nucleopolyhedrovirus (AcMNPV) DNA that contains eight hrs scattered in the genome. Using transformation-associated recombination in yeast, we generated recombinant AcMNPV genomes in which we deleted all hrs or retained a single hr (hr1, hr2, or hr3). Infectious viruses were rescued after transfecting the synthetic viral genomes into host cells, and their replication features were characterized. The results demonstrated that deletion of all hrs severely compromised viral DNA replication and progeny production, whereas retaining only a single hr was essential for efficient viral DNA replication and progeny production. The synthetic virus with hr2 or hr3 showed a growth curve similar to that of the parental virus. Transcriptomic analysis revealed that hr1, hr2, and hr3 could enhance gene transcription within a surrounding region of 14.6 kb, 13.8 kb, and 29.8 kb, respectively. Overall, this study revealed the advantages of synthetic biology in multiloci engineering and functional studies of large DNA viruses. In addition, our findings on hrs will be helpful for the design and improvement of baculovirus-based expression vectors.


Assuntos
Baculoviridae , Replicação Viral , Animais , Baculoviridae/genética , Replicação do DNA/genética , DNA Viral/genética , Spodoptera/genética , Replicação Viral/genética
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