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1.
Cell ; 182(5): 1328-1340.e13, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32814014

RESUMO

Among arthropod vectors, ticks transmit the most diverse human and animal pathogens, leading to an increasing number of new challenges worldwide. Here we sequenced and assembled high-quality genomes of six ixodid tick species and further resequenced 678 tick specimens to understand three key aspects of ticks: genetic diversity, population structure, and pathogen distribution. We explored the genetic basis common to ticks, including heme and hemoglobin digestion, iron metabolism, and reactive oxygen species, and unveiled for the first time that genetic structure and pathogen composition in different tick species are mainly shaped by ecological and geographic factors. We further identified species-specific determinants associated with different host ranges, life cycles, and distributions. The findings of this study are an invaluable resource for research and control of ticks and tick-borne diseases.


Assuntos
Variação Genética/genética , Doenças Transmitidas por Carrapatos/microbiologia , Carrapatos/genética , Animais , Linhagem Celular , Vetores de Doenças , Especificidade de Hospedeiro/genética
2.
Cell ; 172(3): 578-589.e17, 2018 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-29373830

RESUMO

KRASG12C was recently identified to be potentially druggable by allele-specific covalent targeting of Cys-12 in vicinity to an inducible allosteric switch II pocket (S-IIP). Success of this approach requires active cycling of KRASG12C between its active-GTP and inactive-GDP conformations as accessibility of the S-IIP is restricted only to the GDP-bound state. This strategy proved feasible for inhibiting mutant KRAS in vitro; however, it is uncertain whether this approach would translate to in vivo. Here, we describe structure-based design and identification of ARS-1620, a covalent compound with high potency and selectivity for KRASG12C. ARS-1620 achieves rapid and sustained in vivo target occupancy to induce tumor regression. We use ARS-1620 to dissect oncogenic KRAS dependency and demonstrate that monolayer culture formats significantly underestimate KRAS dependency in vivo. This study provides in vivo evidence that mutant KRAS can be selectively targeted and reveals ARS-1620 as representing a new generation of KRASG12C-specific inhibitors with promising therapeutic potential.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Experimentais/tratamento farmacológico , Piperazinas/farmacologia , Proteínas Proto-Oncogênicas p21(ras)/antagonistas & inibidores , Quinazolinas/farmacologia , Animais , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Feminino , Células HCT116 , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Simulação de Acoplamento Molecular , Mutação , Piperazinas/química , Piperazinas/uso terapêutico , Ligação Proteica , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Quinazolinas/química , Quinazolinas/uso terapêutico
3.
PLoS Pathog ; 20(6): e1012271, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38829910

RESUMO

Proper transcription regulation by key transcription factors, such as IRF3, is critical for anti-viral defense. Dynamics of enhancer activity play important roles in many biological processes, and epigenomic analysis is used to determine the involved enhancers and transcription factors. To determine new transcription factors in anti-DNA-virus response, we have performed H3K27ac ChIP-Seq and identified three transcription factors, NR2F6, MEF2D and MAFF, in promoting HSV-1 replication. NR2F6 promotes HSV-1 replication and gene expression in vitro and in vivo, but not dependent on cGAS/STING pathway. NR2F6 binds to the promoter of MAP3K5 and activates AP-1/c-Jun pathway, which is critical for DNA virus replication. On the other hand, NR2F6 is transcriptionally repressed by c-Jun and forms a negative feedback loop. Meanwhile, cGAS/STING innate immunity signaling represses NR2F6 through STAT3. Taken together, we have identified new transcription factors and revealed the underlying mechanisms involved in the network between DNA viruses and host cells.


Assuntos
Herpesvirus Humano 1 , Imunidade Inata , Humanos , Animais , Herpesvirus Humano 1/imunologia , Camundongos , Replicação Viral , Herpes Simples/imunologia , Herpes Simples/virologia , Herpes Simples/metabolismo , Transdução de Sinais , Células HEK293 , Proteínas Repressoras
4.
Nature ; 583(7815): 282-285, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32218527

RESUMO

The ongoing outbreak of viral pneumonia in China and across the world is associated with a new coronavirus, SARS-CoV-21. This outbreak has been tentatively associated with a seafood market in Wuhan, China, where the sale of wild animals may be the source of zoonotic infection2. Although bats are probable reservoir hosts for SARS-CoV-2, the identity of any intermediate host that may have facilitated transfer to humans is unknown. Here we report the identification of SARS-CoV-2-related coronaviruses in Malayan pangolins (Manis javanica) seized in anti-smuggling operations in southern China. Metagenomic sequencing identified pangolin-associated coronaviruses that belong to two sub-lineages of SARS-CoV-2-related coronaviruses, including one that exhibits strong similarity in the receptor-binding domain to SARS-CoV-2. The discovery of multiple lineages of pangolin coronavirus and their similarity to SARS-CoV-2 suggests that pangolins should be considered as possible hosts in the emergence of new coronaviruses and should be removed from wet markets to prevent zoonotic transmission.


Assuntos
Betacoronavirus/genética , Betacoronavirus/isolamento & purificação , Eutérios/virologia , Evolução Molecular , Genoma Viral/genética , Homologia de Sequência do Ácido Nucleico , Sequência de Aminoácidos , Animais , Betacoronavirus/química , Betacoronavirus/classificação , COVID-19 , China/epidemiologia , Quirópteros/virologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/virologia , Reservatórios de Doenças/virologia , Genômica , Humanos , Malásia , Pandemias , Filogenia , Pneumonia Viral/epidemiologia , Pneumonia Viral/transmissão , Pneumonia Viral/virologia , Recombinação Genética , SARS-CoV-2 , Alinhamento de Sequência , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Zoonoses/virologia
5.
PLoS Pathog ; 19(8): e1011580, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37566637

RESUMO

The multigene family genes (MGFs) in the left variable region (LVR) of the African swine fever virus (ASFV) genome have been reported to be involved in viral replication in primary porcine alveolar macrophages (PAMs) and virulence in pigs. However, the exact functions of key MGFs in the LVR that regulate the replication and virulence of ASFV remain unclear. In this study, we identified the MGF300-2R gene to be critical for viral replication in PAMs by deleting different sets of MGFs in the LVR from the highly virulent strain ASFV HLJ/18 (ASFV-WT). The ASFV mutant lacking the MGF300-2R gene (Del2R) showed a 1-log reduction in viral titer, and induced higher IL-1ß and TNF-α production in PAMs than did ASFV-WT. Mechanistically, the MGF300-2R protein was found to interact with and degrade IKKα and IKKß via the selective autophagy pathway. Furthermore, we showed that MGF300-2R promoted the K27-linked polyubiquitination of IKKα and IKKß, which subsequently served as a recognition signal for the cargo receptor TOLLIP-mediated selective autophagic degradation. Importantly, Del2R exhibited a significant reduction in both replication and virulence compared with ASFV-WT in pigs, likely due to the increased IL-1ß and TNF-α, indicating that MGF300-2R is a virulence determinant. These findings reveal that MGF300-2R suppresses host innate immune responses by mediating the degradation of IKKα and IKKß, which provides clues to paving the way for the rational design of live attenuated vaccines to control ASF.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Suínos , Animais , Vírus da Febre Suína Africana/genética , Virulência , Quinase I-kappa B/genética , Quinase I-kappa B/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Macrófagos , Proteínas Serina-Treonina Quinases/metabolismo , Autofagia
6.
Cell Mol Life Sci ; 81(1): 73, 2024 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-38308713

RESUMO

N4 acetylcytidine (ac4C) modification mainly occurs on tRNA, rRNA, and mRNA, playing an important role in the expression of genetic information. However, it is still unclear whether microRNAs have undergone ac4C modification and their potential physiological and pathological functions. In this study, we identified that NAT10/THUMPD1 acetylates primary microRNAs (pri-miRNAs) with ac4C modification. Knockdown of NAT10 suppresses and augments the expression levels of mature miRNAs and pri-miRNAs, respectively. Molecular mechanism studies found that pri-miRNA ac4C promotes the processing of pri-miRNA into precursor miRNA (pre-miRNA) by enhancing the interaction of pri-miRNA and DGCR8, thereby increasing the biogenesis of mature miRNA. Knockdown of NAT10 attenuates the oncogenic characters of lung cancer cells by regulating miRNA production in cancers. Moreover, NAT10 is highly expressed in various clinical cancers and negatively correlated with poor prognosis. Thus, our results reveal that NAT10 plays a crucial role in cancer initiation and progression by modulating pri-miRNA ac4C to affect miRNA production, which would provide an attractive therapeutic strategy for cancers.


Assuntos
MicroRNAs , Neoplasias , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Proteínas de Ligação a RNA/metabolismo , Processamento Pós-Transcricional do RNA/genética , Citidina/genética , Neoplasias/genética
7.
Nucleic Acids Res ; 51(10): 5271-5284, 2023 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-37094074

RESUMO

Liquid-liquid phase separation (LLPS) plays a critical role in regulating gene transcription via the formation of transcriptional condensates. However, LLPS has not been reported to be engineered as a tool to activate endogenous gene expression in mammalian cells or in vivo. Here, we developed a droplet-forming CRISPR (clustered regularly interspaced short palindromic repeats) gene activation system (DropCRISPRa) to activate transcription with high efficiency via combining the CRISPR-SunTag system with FETIDR-AD fusion proteins, which contain an N-terminal intrinsically disordered region (IDR) of a FET protein (FUS or TAF15) and a transcription activation domain (AD, VP64/P65/VPR). In this system, the FETIDR-AD fusion protein formed phase separation condensates at the target sites, which could recruit endogenous BRD4 and RNA polymerase II with an S2 phosphorylated C-terminal domain (CTD) to enhance transcription elongation. IDR-FUS9Y>S and IDR-FUSG156E, two mutants with deficient and aberrant phase separation respectively, confirmed that appropriate phase separation was required for efficient gene activation. Further, the DropCRISPRa system was compatible with a broad set of CRISPR-associated (Cas) proteins and ADs, including dLbCas12a, dAsCas12a, dSpCas9 and the miniature dUnCas12f1, and VP64, P65 and VPR. Finally, the DropCRISPRa system could activate target genes in mice. Therefore, this study provides a robust tool to activate gene expression for foundational research and potential therapeutics.


Assuntos
Sistemas CRISPR-Cas , Ativação Transcricional , Animais , Camundongos , Sistemas CRISPR-Cas/genética , Mamíferos , Proteínas Nucleares/genética , Fatores de Transcrição/genética
8.
Nucleic Acids Res ; 51(7): 3150-3165, 2023 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-36869674

RESUMO

DNA double-strand breaks (DSBs) are functionally linked to genomic instability in spermatocytes and to male infertility. The heavy metal cadmium (Cd) is known to induce DNA damage in spermatocytes by unknown mechanisms. Here, we showed that Cd ions impaired the canonical non-homologous end-joining (NHEJ) repair pathway, but not the homologous recombination (HR) repair pathway, through stimulation of Ser2056 and Thr2609 phosphorylation of DNA-PKcs at DSB sites. Hyper-phosphorylation of DNA-PKcs led to its premature dissociation from DNA ends and the Ku complex, preventing recruitment of processing enzymes and further ligation of DNA ends. Specifically, this cascade was initiated by the loss of PP5 phosphatase activity, which results from the dissociation of PP5 from its activating ions (Mn), that is antagonized by Cd ions through a competitive mechanism. In accordance, in a mouse model Cd-induced genomic instability and consequential male reproductive dysfunction were effectively reversed by a high dosage of Mn ions. Together, our findings corroborate a protein phosphorylation-mediated genomic instability pathway in spermatocytes that is triggered by exchange of heavy metal ions.


Assuntos
Cádmio , Instabilidade Genômica , Infertilidade Masculina , Espermatócitos , Animais , Humanos , Masculino , Camundongos , Cádmio/toxicidade , DNA/metabolismo , Reparo do DNA por Junção de Extremidades , Reparo do DNA , Instabilidade Genômica/efeitos dos fármacos , Infertilidade Masculina/genética , Infertilidade Masculina/metabolismo , Íons/metabolismo , Fosforilação , Reparo de DNA por Recombinação , Espermatócitos/efeitos dos fármacos
9.
Nano Lett ; 24(1): 122-129, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-37913524

RESUMO

Two-dimensional (2D) magnets exhibit unique physical properties for potential applications in spintronics. To date, most 2D ferromagnets are obtained by mechanical exfoliation of bulk materials with van der Waals interlayer interactions, and the synthesis of single- or few-layer 2D ferromagnets with strong interlayer coupling remains experimentally challenging. Here, we report the epitaxial growth of 2D non-van der Waals ferromagnetic bilayer FeSb on SrTiO3(001) substrates stabilized by strong coupling to the substrate, which exhibits in-plane magnetic anisotropy and a Curie temperature above 390 K. In situ low-temperature scanning tunneling microscopy/spectroscopy and density-functional theory calculations further reveal that an Fe Kagome layer terminates the bilayer FeSb. Our results open a new avenue for further exploring emergent quantum phenomena from the interplay of ferromagnetism and topology for application in spintronics.

10.
J Biol Chem ; 299(11): 105347, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37838171

RESUMO

The pseudorabies virus (PRV) TJ strain, a variant of PRV, induces more severe neurological symptoms and higher mortality in piglets and mice than the PRV SC strain isolated in 1980. However, the mechanism underlying responsible for the discrepancy in virulence between these strains remains unclear. Our study investigated the differences in neurotropism between PRV TJ and PRV SC using both in vitro and in vivo models. We discovered that PRV TJ enters neural cells more efficiently than PRV SC. Furthermore, we found that PRV TJ has indistinguishable genomic DNA replication capability and axonal retrograde transport dynamics compared to the PRV SC. To gain deeper insights into the mechanisms underlying these differences, we constructed gene-interchanged chimeric virus constructs and assessed the affinity between envelope glycoprotein B, C, and D (gD) and corresponding receptors. Our findings confirmed that mutations in these envelope proteins, particularly gD, significantly contributed to the heightened attachment and penetration capabilities of PRV TJ. Our study revealed the critical importance of the gDΔR278/P279 and gDV338A in facilitating viral invasion. Furthermore, our observations indicated that mutations in envelope proteins have a more significant impact on viral invasion than on virulence in the mouse model. Our findings provide valuable insights into the roles of natural mutations on the PRV envelope glycoproteins in cell tropism, which sheds light on the relationship between cell tropism and clinical symptoms and offers clues about viral evolution.


Assuntos
Herpesvirus Suídeo 1 , Pseudorraiva , Proteínas do Envelope Viral , Tropismo Viral , Animais , Camundongos , Genômica , Herpesvirus Suídeo 1/genética , Mutagênese , Mutação , Pseudorraiva/genética , Suínos , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/metabolismo
11.
J Am Chem Soc ; 146(13): 9404-9412, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38504578

RESUMO

The catalytic and enantioselective construction of quaternary (all-carbon substituents) stereocenters poses a formidable challenge in organic synthesis due to the hindrance caused by steric factors. One conceptually viable and potentially versatile approach is the coupling of a C-C bond through an outer-sphere mechanism, accompanied by the realization of enantiocontrol through cooperative catalysis; however, examples of such processes are yet to be identified. Herein, we present such a method for creating different compounds with quaternary stereocenters by photoredox/Fe/chiral primary amine triple catalysis. This approach facilitates the connection of an unactivated alkyl source with a tertiary alkyl moiety, which is also rare. The scalable process exhibits mild conditions, does not necessitate the use of a base, and possesses a good functional-group tolerance. Preliminary investigations into the underlying mechanisms have provided valuable insights into the reaction pathway.

12.
Clin Immunol ; 263: 110226, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38663493

RESUMO

Antibiotic resistance and the surge of infectious diseases during the pandemic present significant threats to human health. Trained immunity emerges as a promising and innovative approach to address these infections. Synthetic or natural fungal, parasitic and viral components have been reported to induce trained immunity. However, it is not clear whether bacterial virulence proteins can induce protective trained immunity. Our research demonstrates Streptococcus pneumoniae virulence protein PepO, is a highly potent trained immunity inducer for combating broad-spectrum infection. Our findings showcase that rPepO training confers robust protection to mice against various pathogenic infections by enhancing macrophage functionality. rPepO effectively re-programs macrophages, re-configures their epigenetic modifications and bolsters their immunological responses, which is independent of T or B lymphocytes. In vivo and in vitro experiments confirm that trained macrophage-secreted complement C3 activates peritoneal B lymphocyte and enhances its bactericidal capacity. In addition, we provide the first evidence that granulocyte colony-stimulating factor (G-CSF) derived from trained macrophages plays a pivotal role in shaping central-trained immunity. In summation, our research demonstrates the capability of rPepO to induce both peripheral and central trained immunity in mice, underscoring its potential application in broad-spectrum anti-infection therapy. Our research provides a new molecule and some new target options for infectious disease prevention.


Assuntos
Macrófagos , Camundongos Endogâmicos C57BL , Streptococcus pneumoniae , Animais , Streptococcus pneumoniae/imunologia , Camundongos , Macrófagos/imunologia , Infecções Pneumocócicas/imunologia , Infecções Pneumocócicas/prevenção & controle , Proteínas de Bactérias/imunologia , Linfócitos B/imunologia , Feminino , Imunidade Treinada
13.
Small ; 20(25): e2307261, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38225702

RESUMO

Conventional photodynamic therapy (PDT) of rheumatoid arthritis (RA) faces a dilemma: low-power is insufficient to kill pro-inflammatory cells while high-power exacerbates inflammation. Herein, mitochondrial targeting is introduced in PDT of RA to implement a "less-is-more" strategy, where higher apoptosis in pro-inflammatory cells are achieved with lower laser power. In arthritic rats, chlorine 6-loaded and mitochondria-targeting liposomes (Ce6@M-Lip) passively accumulated in inflamed joints, entered pro-inflammatory macrophages, and actively localized to mitochondria, leading to enhanced mitochondrial dysfunction under laser irradiation. By effectively disrupting mitochondria, pro-inflammatory macrophages are more susceptible to PDT, resulting in increased apoptosis initiation. Additionally, it identifies that high-power irradiation caused cell rupture and release of endogenous danger signals that recruited and activated additional macrophages. In contrast, under low-power irradiation, mitochondria-targeting Ce6@M-Lip not only prevented inflammation but also reduced pro-inflammatory macrophage infiltration and pro-inflammatory cytokine secretion. Overall, targeting mitochondria reconciled therapeutic efficacy and inflammation, thus enabling efficacious yet inflammation-sparing PDT for RA. This highlights the promise of mitochondrial targeting to resolve the dilemma between anti-inflammatory efficacy and inflammatory exacerbation in PDT by implementing a "less-is-more" strategy.


Assuntos
Artrite Reumatoide , Lipossomos , Mitocôndrias , Fotoquimioterapia , Animais , Fotoquimioterapia/métodos , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/metabolismo , Lipossomos/química , Macrófagos/metabolismo , Macrófagos/efeitos dos fármacos , Ratos , Apoptose/efeitos dos fármacos , Inflamação/tratamento farmacológico , Inflamação/patologia
14.
J Virol ; 97(9): e0056923, 2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37607059

RESUMO

Proinflammatory factors play important roles in the pathogenesis of African swine fever virus (ASFV), which is the causative agent of African swine fever (ASF), a highly contagious and severe hemorrhagic disease. Efforts in the prevention and treatment of ASF have been severely hindered by knowledge gaps in viral proteins responsible for modulating host antiviral responses. In this study, we identified the I10L protein (pI10L) of ASFV as a potential inhibitor of the TNF-α- and IL-1ß-triggered NF-κB signaling pathway, the most canonical and important part of host inflammatory responses. The ectopically expressed pI10L remarkably suppressed the activation of NF-κB signaling in HEK293T and PK-15 cells. The ASFV mutant lacking the I10L gene (ASFVΔI10L) induced higher levels of proinflammatory cytokines production in primary porcine alveolar macrophages (PAMs) compared with its parental ASFV HLJ/2018 strain (ASFVWT). Mechanistic studies suggest that pI10L inhibits IKKß phosphorylation by reducing the K63-linked ubiquitination of NEMO, which is necessary for the activation of IKKß. Morever, pI10L interacts with the kinase domain of IKKß through its N-terminus, and consequently blocks the association of IKKß with its substrates IκBα and p65, leading to reduced phosphorylation. In addition, the nuclear translocation efficiency of p65 was also altered by pI10L. Further biochemical evidence supported that the amino acids 1-102 on pI10L were essential for the pI10L-mediated suppression of the NF-κB signaling pathway. The present study clarifies the immunosuppressive activity of pI10L, and provides novel insights into the understanding of ASFV pathobiology and the development of vaccines against ASF. IMPORTANCE African swine fever (ASF), caused by the African swine fever virus (ASFV), is now widespread in many countries and severely affects the commercial rearing of swine. To date, few safe and effective vaccines or antiviral strategies have been marketed due to large gaps in knowledge regarding ASFV pathobiology and immune evasion mechanisms. In this study, we deciphered the important role of the ASFV-encoded I10L protein in the TNF-α-/IL-1ß-triggered NF-κB signaling pathway. This study provides novel insights into the pathogenesis of ASFV and thus contributes to the development of vaccines against ASF.

15.
J Virol ; 97(5): e0020923, 2023 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-37120831

RESUMO

Human adenoviruses type 3 (HAdV-3) and type 55 (HAdV-55) are frequently encountered, highly contagious respiratory pathogens with high morbidity rate. In contrast to HAdV-3, one of the most predominant types in children, HAdV-55 is a reemergent pathogen associated with more severe community-acquired pneumonia (CAP) in adults, especially in military camps. However, the infectivity and pathogenicity differences between these viruses remain unknown as in vivo models are not available. Here, we report a novel system utilizing human embryonic stem cells-derived 3-dimensional airway organoids (hAWOs) and alveolar organoids (hALOs) to investigate these two viruses. Firstly, HAdV-55 replicated more robustly than HAdV-3. Secondly, cell tropism analysis in hAWOs and hALOs by immunofluorescence staining revealed that HAdV-55 infected more airway and alveolar stem cells (basal and AT2 cells) than HAdV-3, which may lead to impairment of self-renewal functions post-injury and the loss of cell differentiation in lungs. Additionally, the viral life cycles of HAdV-3 and -55 in organoids were also observed using Transmission Electron Microscopy. This study presents a useful pair of lung organoids for modeling infection and replication differences between respiratory pathogens, illustrating that HAdV-55 has relatively higher replication efficiency and more specific cell tropism in human lung organoids than HAdV-3, which may result in relatively higher pathogenicity and virulence of HAdV-55 in human lungs. The model system is also suitable for evaluating potential antiviral drugs, as demonstrated with cidofovir. IMPORTANCE Human adenovirus (HAdV) infections are a major threat worldwide. HAdV-3 is one of the most predominant respiratory pathogen types found in children. Many clinical studies have reported that HAdV-3 causes less severe disease. In contrast, HAdV-55, a reemergent acute respiratory disease pathogen, is associated with severe community-acquired pneumonia in adults. Currently, no ideal in vivo models are available for studying HAdVs. Therefore, the mechanism of infectivity and pathogenicity differences between human adenoviruses remain unknown. In this study, a useful pair of 3-dimensional (3D) airway organoids (hAWOs) and alveolar organoids (hALOs) were developed to serve as a model. The life cycles of HAdV-3 and HAdV-55 in these human lung organoids were documented for the first time. These 3D organoids harbor different cell types, which are similar to the ones found in humans. This allows for the study of the natural target cells for infection. The finding of differences in replication efficiency and cell tropism between HAdV-55 and -3 may provide insights into the mechanism of clinical pathogenicity differences between these two important HAdV types. Additionally, this study provides a viable and effective in vitro tool for evaluating potential anti-adenoviral treatments.


Assuntos
Infecções por Adenovirus Humanos , Adenovírus Humanos , Antivirais , Células-Tronco Embrionárias Humanas , Adulto , Criança , Humanos , Infecções por Adenovirus Humanos/tratamento farmacológico , Infecções por Adenovirus Humanos/virologia , Adenovírus Humanos/classificação , Adenovírus Humanos/fisiologia , Antivirais/farmacologia , Pulmão/virologia , Organoides , Pneumonia , Especificidade da Espécie
16.
J Virol ; 97(10): e0082423, 2023 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-37724880

RESUMO

IMPORTANCE: African swine fever (ASF) is an acute, hemorrhagic, and severe porcine infectious disease caused by African swine fever virus (ASFV). ASF outbreaks severely threaten the global pig industries and result in serious economic losses. No safe and efficacious commercial vaccine is currently available except in Vietnam. To date, large gaps in the knowledge concerning viral biological characteristics and immunoevasion strategies have hindered the ASF vaccine design. In this study, we demonstrate that pD129L negatively regulates the type I interferon (IFN) signaling pathway by interfering with the interaction of the transcriptional coactivator p300 and IRF3, thereby inhibiting the induction of type I IFNs. This study reveals a novel immunoevasion strategy employed by ASFV, shedding new light on the intricate mechanisms for ASFV to evade the host immune responses.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Proteína p300 Associada a E1A , Fator Regulador 3 de Interferon , Interferon Tipo I , Animais , Febre Suína Africana/virologia , Interferon Tipo I/metabolismo , Interferon beta/metabolismo , Suínos , Fatores de Transcrição/metabolismo , Vacinas/metabolismo , Proteína p300 Associada a E1A/metabolismo , Fator Regulador 3 de Interferon/metabolismo , Evasão da Resposta Imune
17.
BMC Cancer ; 24(1): 506, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38649860

RESUMO

BACKGROUND: N1-methyladenosine (m1A), among the most common internal modifications on RNAs, has a crucial role to play in cancer development. The purpose of this study were systematically investigate the modification characteristics of m1A in hepatocellular carcinoma (HCC) to unveil its potential as an anticancer target and to develop a model related to m1A modification characteristics with biological functions. This model could predict the prognosis for patients with HCC. METHODS: An integrated analysis of the TCGA-LIHC database was performed to explore the gene signatures and clinical relevance of 10 m1A regulators. Furthermore, the biological pathways regulated by m1A modification patterns were investigated. The risk model was established using the genes that showed differential expression (DEGs) between various m1A modification patterns and autophagy clusters. These in vitro experiments were subsequently designed to validate the role of m1A in HCC cell growth and autophagy. Immunohistochemistry was employed to assess m1A levels and the expression of DEGs from the risk model in HCC tissues and paracancer tissues using tissue microarray. RESULTS: The risk model, constructed from five DEGs (CDK5R2, TRIM36, DCAF8L, CYP26B, and PAGE1), exhibited significant prognostic value in predicting survival rates among individuals with HCC. Moreover, HCC tissues showed decreased levels of m1A compared to paracancer tissues. Furthermore, the low m1A level group indicated a poorer clinical outcome for patients with HCC. Additionally, m1A modification may positively influence autophagy regulation, thereby inhibiting HCC cells proliferation under nutrient deficiency conditions. CONCLUSIONS: The risk model, comprising m1A regulators correlated with autophagy and constructed from five DEGs, could be instrumental in predicting HCC prognosis. The reduced level of m1A may represent a potential target for anti-HCC strategies.


Assuntos
Autofagia , Carcinoma Hepatocelular , Regulação Neoplásica da Expressão Gênica , Metilação de RNA , Feminino , Humanos , Masculino , Adenosina/análogos & derivados , Adenosina/metabolismo , Autofagia/genética , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/mortalidade , Linhagem Celular Tumoral , Proliferação de Células , Metilação de DNA , Perfilação da Expressão Gênica , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/mortalidade , Prognóstico , Metilação de RNA/genética
18.
Mol Psychiatry ; 28(3): 1383-1395, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36481932

RESUMO

In response to stressful events, the hypothalamic-pituitary-adrenal (HPA) axis is activated, and consequently glucocorticoids are released by the adrenal gland into the blood circulation. A large body of research has illustrated that excessive glucocorticoids in the hippocampus exerts negative feedback regulation of the HPA axis through glucocorticoid receptor (GR), which is critical for the homeostasis of the HPA axis. Maternal prenatal stress causes dysfunction of the HPA axis feedback mechanism in their offspring in adulthood. Here we report that telomerase reverse transcriptase (TERT) gene knockout causes hyperactivity of the HPA axis without hippocampal GR deficiency. We found that the level of TERT in the dentate gyrus (DG) of the hippocampus during the developmental stage determines the responses of the HPA axis to stressful events in adulthood through modulating the excitability of the dentate granular cells (DGCs) rather than the expression of GR. Our study also suggests that the prenatal high level of glucocorticoids exposure-induced hypomethylation at Chr13:73764526 in the first exon of mouse Tert gene accounted for TERT deficiency in the DG and HPA axis abnormality in the adult offspring. This study reveals a novel GR-independent mechanism underlying prenatal stress-associated HPA axis impairment, providing a new angle for understanding the mechanisms for maintaining HPA axis homeostasis.


Assuntos
Sistema Hipotálamo-Hipofisário , Receptores de Glucocorticoides , Feminino , Gravidez , Animais , Camundongos , Sistema Hipotálamo-Hipofisário/metabolismo , Receptores de Glucocorticoides/metabolismo , Glucocorticoides/metabolismo , Sistema Hipófise-Suprarrenal/metabolismo , Homeostase
19.
Eur Radiol ; 34(4): 2608-2618, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37840099

RESUMO

OBJECTIVE: To develop a bimodal nomogram to reduce unnecessary biopsies in breast lesions with discordant ultrasound (US) and mammography (MG) Breast Imaging Reporting and Data System (BI-RADS) assessments. METHODS: This retrospective study enrolled 706 women following opportunistic screening or diagnosis with discordant US and MG BI-RADS assessments (where one assessed a lesion as BI-RADS 4 or 5, while the other assessed the same lesion as BI-RADS 0, 2, or 3) from two medical centres between June 2019 and June 2021. Univariable and multivariable logistic regression analyses were used to develop the nomogram. DeLong's and McNemar's tests were used to assess the model's performance. RESULTS: Age, MG features (margin, shape, and density in masses, suspicious calcifications, and architectural distortion), and US features (margin and shape in masses as well as calcifications) were independent risk factors for breast cancer. The nomogram obtained an area under the curve of 0.87 (95% confidence interval (CI), 0.83-0.91), 0.91 (95% CI, 0.87 - 0.96), and 0.92 (95% CI, 0.86-0.98) in the training, internal validation, and external testing samples, respectively, and demonstrated consistency in calibration curves. Coupling the nomogram with US reduced unnecessary biopsies from 74 to 44% and the missed malignancies rate from 13 to 2%. Similarly, coupling with MG reduced missed malignancies from 20 to 6%, and 63% of patients avoided unnecessary biopsies. Interobserver agreement between US and MG increased from - 0.708 (poor agreement) to 0.700 (substantial agreement) with the nomogram. CONCLUSION: When US and MG BI-RADS assessments are discordant, incorporating the nomogram may improve the diagnostic accuracy, avoid unnecessary breast biopsies, and minimise missed diagnoses. CLINICAL RELEVANCE STATEMENT: The nomogram developed in this study could be used as a computer program to assist radiologists with detecting breast cancer and ensuring more precise management and improved treatment decisions for breast lesions with discordant assessments in clinical practice. KEY POINTS: • Coupling the nomogram with US and mammography improves the detection of breast cancers without the risk of unnecessary biopsy or missed malignancies. • The nomogram increases mammography and US interobserver agreement and enhances the consistency of decision-making. • The nomogram has the potential to be a computer program to assist radiologists in identifying breast cancer and making optimal decisions.


Assuntos
Neoplasias da Mama , Nomogramas , Feminino , Humanos , Estudos Retrospectivos , Ultrassom , Mamografia/métodos , Neoplasias da Mama/patologia , Biópsia
20.
Int Microbiol ; 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38190086

RESUMO

Sulfitobacter is a bacterium recognized for its production of AMP-independent sulfite oxidase, which is instrumental in the creation of sulfite biosensors. This capability underscores its ecological and economic relevance. In this study, we present a newly discovered phage, Sulfitobacter phage vB_SupP_AX, which was isolated from Maidao of Qingdao, China. The vB_SupP_AX genome is linear and double-stranded and measures 75,445 bp with a GC content of 49%. It encompasses four transfer RNA (tRNA) sequences and 79 open reading frames (ORFs), one of which is an auxiliary metabolic gene encoding thioredoxin. Consistent with other N4-like phages, vB_SupP_AX possesses three distinct RNA polymerases and is characterized by the presence of four tRNA molecules. Comparative genomic and phylogenetic analyses position vB_SupP_AX and three other viral genomes from the Integrated Microbial Genomes/Virus v4 database within the Rhodovirinae virus subfamily. The identification of vB_SupP_AX enhances our understanding of virus-host interactions within marine ecosystems.

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