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1.
Cell ; 186(19): 4074-4084.e11, 2023 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-37669665

RESUMO

H3N8 avian influenza viruses (AIVs) in China caused two confirmed human infections in 2022, followed by a fatal case reported in 2023. H3N8 viruses are widespread in chicken flocks; however, the zoonotic features of H3N8 viruses are poorly understood. Here, we demonstrate that H3N8 viruses were able to infect and replicate efficiently in organotypic normal human bronchial epithelial (NHBE) cells and lung epithelial (Calu-3) cells. Human isolates of H3N8 virus were more virulent and caused severe pathology in mice and ferrets, relative to chicken isolates. Importantly, H3N8 virus isolated from a patient with severe pneumonia was transmissible between ferrets through respiratory droplets; it had acquired human-receptor-binding preference and amino acid substitution PB2-E627K necessary for airborne transmission. Human populations, even when vaccinated against human H3N2 virus, appear immunologically naive to emerging mammalian-adapted H3N8 AIVs and could be vulnerable to infection at epidemic or pandemic proportion.


Assuntos
Vírus da Influenza A Subtipo H3N8 , Influenza Humana , Animais , Humanos , Camundongos , Galinhas , Furões , Vírus da Influenza A Subtipo H3N2 , Aerossóis e Gotículas Respiratórios
2.
Cell ; 184(17): 4380-4391.e14, 2021 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-34147139

RESUMO

Despite the discovery of animal coronaviruses related to SARS-CoV-2, the evolutionary origins of this virus are elusive. We describe a meta-transcriptomic study of 411 bat samples collected from a small geographical region in Yunnan province, China, between May 2019 and November 2020. We identified 24 full-length coronavirus genomes, including four novel SARS-CoV-2-related and three SARS-CoV-related viruses. Rhinolophus pusillus virus RpYN06 was the closest relative of SARS-CoV-2 in most of the genome, although it possessed a more divergent spike gene. The other three SARS-CoV-2-related coronaviruses carried a genetically distinct spike gene that could weakly bind to the hACE2 receptor in vitro. Ecological modeling predicted the co-existence of up to 23 Rhinolophus bat species, with the largest contiguous hotspots extending from South Laos and Vietnam to southern China. Our study highlights the remarkable diversity of bat coronaviruses at the local scale, including close relatives of both SARS-CoV-2 and SARS-CoV.


Assuntos
COVID-19/virologia , Quirópteros/virologia , Coronavirus/genética , Evolução Molecular , SARS-CoV-2/genética , Sequência de Aminoácidos , Enzima de Conversão de Angiotensina 2/química , Enzima de Conversão de Angiotensina 2/metabolismo , Animais , Sudeste Asiático , China , Coronavirus/classificação , Coronavirus/isolamento & purificação , Fenômenos Ecológicos e Ambientais , Genoma Viral , Humanos , Modelos Moleculares , Filogenia , SARS-CoV-2/fisiologia , Alinhamento de Sequência , Análise de Sequência de RNA , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo , Zoonoses Virais
3.
Cell ; 177(7): 1714-1724.e12, 2019 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-31080063

RESUMO

Arthritogenic alphaviruses, such as Chikungunya virus (CHIKV), cause severe and debilitating rheumatic diseases worldwide, resulting in severe morbidity and economic costs. Recently, MXRA8 was reported as an entry receptor. Here, we present the crystal structures of the mouse MXRA8, human MXRA8 in complex with the CHIKV E protein, and the cryo-electron microscopy structure of human MXRA8 and CHIKV virus-like particle. MXRA8 has two Ig-like domains with unique structural topologies. This receptor binds in the "canyon" between two protomers of the E spike on the surface of the virion. The atomic details at the interface between the two binding entities reveal that both the two domains and the hinge region of MXRA8 are involved in interaction with CHIKV E1-E2 residues from two protomers. Notably, the stalk region of MXRA8 is critical for CHIKV virus entry. This finding provides important information regarding the development of therapeutic countermeasures against those arthritogenic alphaviruses.


Assuntos
Vírus Chikungunya/química , Proteínas de Membrana/química , Proteínas do Envelope Viral/química , Internalização do Vírus , Animais , Vírus Chikungunya/metabolismo , Chlorocebus aethiops , Células HEK293 , Humanos , Proteínas de Membrana/metabolismo , Domínios Proteicos , Células Vero , Proteínas do Envelope Viral/metabolismo
4.
Cell ; 177(6): 1553-1565.e16, 2019 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-31104841

RESUMO

Enterovirus B (EV-B), a major proportion of the genus Enterovirus in the family Picornaviridae, is the causative agent of severe human infectious diseases. Although cellular receptors for coxsackievirus B in EV-B have been identified, receptors mediating virus entry, especially the uncoating process of echovirus and other EV-B remain obscure. Here, we found that human neonatal Fc receptor (FcRn) is the uncoating receptor for major EV-B. FcRn binds to the virus particles in the "canyon" through its FCGRT subunit. By obtaining multiple cryo-electron microscopy structures at different stages of virus entry at atomic or near-atomic resolution, we deciphered the underlying mechanisms of enterovirus attachment and uncoating. These structures revealed that different from the attachment receptor CD55, binding of FcRn to the virions induces efficient release of "pocket factor" under acidic conditions and initiates the conformational changes in viral particle, providing a structural basis for understanding the mechanisms of enterovirus entry.


Assuntos
Enterovirus Humano B/metabolismo , Antígenos de Histocompatibilidade Classe I/metabolismo , Antígenos de Histocompatibilidade Classe I/ultraestrutura , Receptores Fc/metabolismo , Receptores Fc/ultraestrutura , Capsídeo/metabolismo , Microscopia Crioeletrônica , Enterovirus , Enterovirus Humano B/patogenicidade , Infecções por Enterovirus/metabolismo , Antígenos de Histocompatibilidade Classe I/fisiologia , Humanos , Modelos Moleculares , Filogenia , Receptores Fc/fisiologia , Vírion , Internalização do Vírus
5.
PLoS Pathog ; 20(9): e1012508, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39303003

RESUMO

Influenza and coronavirus disease 2019 (COVID-19) represent two respiratory diseases that have significantly impacted global health, resulting in substantial disease burden and mortality. An optimal solution would be a combined vaccine capable of addressing both diseases, thereby obviating the need for multiple vaccinations. Previously, we conceived a chimeric protein subunit vaccine targeting both influenza virus and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), utilizing the receptor binding domain of spike protein (S-RBD) and the stalk region of hemagglutinin protein (HA-stalk) components. By integrating the S-RBD from the SARS-CoV-2 Delta variant with the headless hemagglutinin (HA) from H1N1 influenza virus, we constructed stable trimeric structures that remain accessible to neutralizing antibodies. This vaccine has demonstrated its potential by conferring protection against a spectrum of strains in mouse models. In this study, we designed an mRNA vaccine candidate encoding the chimeric antigen. The resultant humoral and cellular immune responses were meticulously evaluated in mouse models. Furthermore, the protective efficacy of the vaccine was rigorously examined through challenges with either homologous or heterologous influenza viruses or SARS-CoV-2 strains. Our findings reveal that the mRNA vaccine exhibited robust immunogenicity, engendering high and sustained levels of neutralizing antibodies accompanied by robust and persistent cellular immunity. Notably, this vaccine effectively afforded complete protection to mice against H1N1 or heterosubtypic H5N8 subtypes, as well as the SARS-CoV-2 Delta and Omicron BA.2 variants. Additionally, our mRNA vaccine design can be easily adapted from Delta RBD to Omicron RBD antigens, providing protection against emerging variants. The development of two-in-one vaccine targeting both influenza and COVID-19, incorporating the mRNA platform, may provide a versatile approach to combating future pandemics.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Glicoproteínas de Hemaglutininação de Vírus da Influenza , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Vacinas de mRNA , Animais , Camundongos , SARS-CoV-2/imunologia , COVID-19/prevenção & controle , COVID-19/imunologia , Vacinas de mRNA/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/genética , Humanos , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Vacinas contra COVID-19/imunologia , Vacinas contra Influenza/imunologia , Anticorpos Antivirais/imunologia , Camundongos Endogâmicos BALB C , Feminino , Vírus da Influenza A Subtipo H1N1/imunologia , Infecções por Orthomyxoviridae/prevenção & controle , Infecções por Orthomyxoviridae/imunologia , Vacinas Sintéticas/imunologia , Influenza Humana/prevenção & controle , Influenza Humana/imunologia , Anticorpos Neutralizantes/imunologia
6.
PLoS Pathog ; 20(8): e1012487, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39213280

RESUMO

Protective vaccines are crucial for preventing and controlling coronavirus disease 2019 (COVID-19). Updated vaccines are needed to confront the continuously evolving and circulating severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants. These vaccines should be safe, effective, amenable to easily scalable production, and affordable. Previously, we developed receptor binding domain (RBD) dimer-based protein subunit vaccines (ZF2001 and updated vaccines) in mammalian cells. In this study, we explored a strategy for producing RBD-dimer immunogens in Pichia pastoris. We found that wild-type P. pastoris produced hyperglycosylated RBD-dimer protein containing four N-glycosylation sites in P. pastoris. Therefore, we engineered the wild type P. pastoris (GS strain) into GSΔOCH1pAO by deleting the OCH1 gene (encoding α-1,6-mannosyltransferase enzyme) to decrease glycosylation, as well as by overexpressing the HIS4 gene (encoding histidine dehydrogenase) to increase histidine synthesis for better growth. In addition, RBD-dimer protein was truncated to remove the R328/F329 cleavage sites in P. pastoris. Several homogeneous RBD-dimer proteins were produced in the GSΔOCH1pAO strain, demonstrating the feasibility of using the P. pastoris expression system. We further resolved the cryo-EM structure of prototype-Beta RBD-dimer complexed with the neutralizing antibody CB6 to reveal the completely exposed immune epitopes of the RBDs. In a murine model, we demonstrated that the yeast-produced RBD-dimer induces robust and protective antibody responses, which is suitable for boosting immunization. This study developed the yeast system for producing SARS-CoV-2 RBD-dimer immunogens, providing a promising platform and pipeline for the future continuous updating and production of SARS-CoV-2 vaccines.


Assuntos
Vacinas contra COVID-19 , COVID-19 , SARS-CoV-2 , SARS-CoV-2/imunologia , SARS-CoV-2/genética , Animais , Camundongos , COVID-19/prevenção & controle , COVID-19/imunologia , Vacinas contra COVID-19/imunologia , Glicosilação , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/genética , Humanos , Anticorpos Neutralizantes/imunologia , Camundongos Endogâmicos BALB C , Anticorpos Antivirais/imunologia , Saccharomycetales/genética , Saccharomycetales/imunologia , Saccharomycetales/metabolismo , Feminino , Pichia/genética , Pichia/metabolismo
7.
Plant Cell ; 35(4): 1241-1258, 2023 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-36648110

RESUMO

In Arabidopsis thaliana, female gametophyte (FG) development is accompanied by the formation and expansion of the large vacuole in the FG; this is essential for FG expansion, nuclear polar localization, and cell fate determination. Arabidopsis VACUOLELESS GAMETOPHYTES (VLG) facilitates vesicular fusion to form large vacuole in the FG, but the regulation of VLG remains largely unknown. Here, we found that gain-of-function mutation of BRASSINOSTEROID INSENSITIVE2 (BIN2) (bin2-1) increases VLG abundance to induce the vacuole formation at stage FG1, and leads to abortion of FG. Loss-of-function mutation of BIN2 and its homologs (bin2-3 bil1 bil2) reduced VLG abundance and mimicked vlg/VLG phenotypes. Knocking down VLG in bin2-1 decreased the ratio of aberrant vacuole formation at stage FG1, whereas FG1-specific overexpression of VLG mimicked the bin2-1 phenotype. VLG partially rescued the bin2-3 bil1 bil2 phenotype, demonstrating that VLG acts downstream of BIN2. Mutation of VLG residues that are phosphorylated by BIN2 altered VLG stability and a phosphorylation mimic of VLG causes similar defects as did bin2-1. Therefore, BIN2 may function by interacting with and phosphorylating VLG in the FG to enhance its stability and abundance, thus facilitating vacuole formation. Our findings provide mechanistic insight into how the BIN2-VLG module regulates the spatiotemporal formation of the large vacuole in FG development.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/fisiologia , Proteínas de Arabidopsis/metabolismo , Brassinosteroides/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Células Germinativas Vegetais/metabolismo , Óvulo Vegetal/genética , Óvulo Vegetal/metabolismo , Fosforilação , Proteínas Quinases/metabolismo , Transdução de Sinais/genética , Vacúolos/metabolismo
8.
Proc Natl Acad Sci U S A ; 120(18): e2215098120, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-37094126

RESUMO

CRISPR-Cas systems are widespread adaptive antiviral systems used in prokaryotes. Some phages, in turn, although have small genomes can economize the use of genetic space to encode compact or incomplete CRISPR-Cas systems to inhibit the host and establish infection. Phage ICP1, infecting Vibrio cholerae, encodes a compact type I-F CRISPR-Cas system to suppress the antiphage mobile genetic element in the host genome. However, the mechanism by which this compact system recognizes the target DNA and executes interference remains elusive. Here, we present the electron cryo-microscopy (cryo-EM) structures of both apo- and DNA-bound ICP1 surveillance complexes (Aka Csy complex). Unlike most other type I surveillance complexes, the ICP1 Csy complex lacks the Cas11 subunit or a structurally homologous domain, which is crucial for dsDNA binding and Cas3 activation in other type I CRISPR-Cas systems. Structural and functional analyses revealed that the compact ICP1 Csy complex alone is inefficient in binding to dsDNA targets, presumably stalled at a partial R-loop conformation. The presence of Cas2/3 facilitates dsDNA binding and allows effective dsDNA target cleavage. Additionally, we found that Pseudomonas aeruginosa Cas2/3 efficiently cleaved the dsDNA target presented by the ICP1 Csy complex, but not vice versa. These findings suggest a unique mechanism for target dsDNA binding and cleavage by the compact phage-derived CRISPR-Cas system.


Assuntos
Bacteriófagos , Proteínas Associadas a CRISPR , Bacteriófagos/genética , Sistemas CRISPR-Cas , DNA , Proteínas Associadas a CRISPR/metabolismo
9.
Proc Natl Acad Sci U S A ; 120(40): e2302361120, 2023 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-37738291

RESUMO

The almost simultaneous emergence of major animal phyla during the early Cambrian shaped modern animal biodiversity. Reconstructing evolutionary relationships among such closely spaced branches in the animal tree of life has proven to be a major challenge, hindering understanding of early animal evolution and the fossil record. This is particularly true in the species-rich and highly varied Mollusca where dramatic inconsistency among paleontological, morphological, and molecular evidence has led to a long-standing debate about the group's phylogeny and the nature of dozens of enigmatic fossil taxa. A critical step needed to overcome this issue is to supplement available genomic data, which is plentiful for well-studied lineages, with genomes from rare but key lineages, such as Scaphopoda. Here, by presenting chromosome-level genomes from both extant scaphopod orders and leveraging complete genomes spanning Mollusca, we provide strong support for Scaphopoda as the sister taxon of Bivalvia, revitalizing the morphology-based Diasoma hypothesis originally proposed 50 years ago. Our molecular clock analysis confidently dates the split between Bivalvia and Scaphopoda at ~520 Ma, prompting a reinterpretation of controversial laterally compressed Early Cambrian fossils, including Anabarella, Watsonella, and Mellopegma, as stem diasomes. Moreover, we show that incongruence in the phylogenetic placement of Scaphopoda in previous phylogenomic studies was due to ancient incomplete lineage sorting (ILS) that occurred during the rapid radiation of Conchifera. Our findings highlight the need to consider ILS as a potential source of error in deep phylogeny reconstruction, especially in the context of the unique nature of the Cambrian Explosion.


Assuntos
Bivalves , Animais , Filogenia , Biodiversidade , Movimento Celular , Suplementos Nutricionais
10.
Plant J ; 119(2): 879-894, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38923085

RESUMO

Cotton is a globally cultivated crop, producing 87% of the natural fiber used in the global textile industry. The pigment glands, unique to cotton and its relatives, serve as a defense structure against pests and pathogens. However, the molecular mechanism underlying gland formation and the specific role of pigment glands in cotton's pest defense are still not well understood. In this study, we cloned a gland-related transcription factor GhHAM and generated the GhHAM knockout mutant using CRISPR/Cas9. Phenotypic observations, transcriptome analysis, and promoter-binding experiments revealed that GhHAM binds to the promoter of GoPGF, regulating pigment gland formation in cotton's multiple organs via the GoPGF-GhJUB1 module. The knockout of GhHAM significantly reduced gossypol production and increased cotton's susceptibility to pests in the field. Feeding assays demonstrated that more than 80% of the cotton bollworm larvae preferred ghham over the wild type. Furthermore, the ghham mutants displayed shorter cell length and decreased gibberellins (GA) production in the stem. Exogenous application of GA3 restored stem cell elongation but not gland formation, thereby indicating that GhHAM controls gland morphogenesis independently of GA. Our study sheds light on the functional differentiation of HAM proteins among plant species, highlights the significant role of pigment glands in influencing pest feeding preference, and provides a theoretical basis for breeding pest-resistant cotton varieties to address the challenges posed by frequent outbreaks of pests.


Assuntos
Regulação da Expressão Gênica de Plantas , Gossypium , Proteínas de Plantas , Gossypium/genética , Gossypium/parasitologia , Gossypium/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Animais , Giberelinas/metabolismo , Gossipol/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Resistência à Doença/genética , Doenças das Plantas/parasitologia , Doenças das Plantas/imunologia , Mariposas/fisiologia , Larva/crescimento & desenvolvimento
11.
J Virol ; 98(3): e0153623, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38315014

RESUMO

African swine fever (ASF) is a highly contagious viral disease that affects domestic and wild pigs. The causative agent of ASF is African swine fever virus (ASFV), a large double-stranded DNA virus with a complex virion structure. Among the various proteins encoded by ASFV, A137R is a crucial structural protein associated with its virulence. However, the structure and molecular mechanisms underlying the functions of A137R remain largely unknown. In this study, we present the structure of A137R determined by cryogenic electron microscopy single-particle reconstruction, which reveals that A137R self-oligomerizes to form a dodecahedron-shaped cage composed of 60 polymers. The dodecahedron is literally equivalent to a T = 1 icosahedron where the icosahedral vertexes are located in the center of each dodecahedral facet. Within each facet, five A137R protomers are arranged in a head-to-tail orientation with a long N-terminal helix forming the edge through which adjacent facets stitch together to form the dodecahedral cage. Combining structural analysis and biochemical evidence, we demonstrate that the N-terminal domain of A137R is crucial and sufficient for mediating the assembly of the dodecahedron. These findings imply the role of A137R cage as a core component in the icosahedral ASFV virion and suggest a promising molecular scaffold for nanotechnology applications. IMPORTANCE: African swine fever (ASF) is a lethal viral disease of pigs caused by African swine fever virus (ASFV). No commercial vaccines and antiviral treatments are available for the prevention and control of the disease. A137R is a structural protein of ASFV that is associated with its virulence. The discovery of the dodecahedron-shaped cage structure of A137R in this study is of great importance in understanding ASFV pathogenicity. This finding sheds light on the molecular mechanisms underlying the functions of A137R. Furthermore, the dodecahedral cage formed by A137R shows promise as a molecular scaffold for nanoparticle vectors. Overall, this study provides valuable insights into the structure and function of A137R, contributing to our understanding of ASFV and potentially opening up new avenues for the development of vaccines or treatments for ASF.


Assuntos
Vírus da Febre Suína Africana , Suínos , Proteínas Estruturais Virais , Animais , Febre Suína Africana/virologia , Vírus da Febre Suína Africana/química , Vírus da Febre Suína Africana/crescimento & desenvolvimento , Vírus da Febre Suína Africana/patogenicidade , Vírus da Febre Suína Africana/ultraestrutura , Microscopia Crioeletrônica , Relação Estrutura-Atividade , Suínos/virologia , Proteínas Estruturais Virais/química , Proteínas Estruturais Virais/metabolismo , Proteínas Estruturais Virais/ultraestrutura , Vírion/química , Vírion/metabolismo , Vírion/ultraestrutura , Virulência
12.
EMBO Rep ; 24(10): e56098, 2023 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-37522391

RESUMO

A11 dopaminergic neurons regulate somatosensory transduction by projecting from the diencephalon to the spinal cord, but the function of this descending projection in itch remained elusive. Here, we report that dopaminergic projection neurons from the A11 nucleus to the spinal dorsal horn (dopaminergicA11-SDH ) are activated by pruritogens. Inhibition of these neurons alleviates itch-induced scratching behaviors. Furthermore, chemogenetic inhibition of spinal dopamine receptor D1-expressing (DRD1+ ) neurons decreases acute or chronic itch-induced scratching. Mechanistically, spinal DRD1+ neurons are excitatory and mostly co-localize with gastrin-releasing peptide (GRP), an endogenous neuropeptide for itch. In addition, DRD1+ neurons form synapses with GRP receptor-expressing (GRPR+ ) neurons and activate these neurons via AMPA receptor (AMPAR). Finally, spontaneous itch and enhanced acute itch induced by activating spinal DRD1+ neurons are relieved by antagonists against AMPAR and GRPR. Thus, the descending dopaminergic pathway facilitates spinal itch transmission via activating DRD1+ neurons and releasing glutamate and GRP, which directly augments GRPR signaling. Interruption of this descending pathway may be used to treat chronic itch.


Assuntos
Receptores da Bombesina , Medula Espinal , Humanos , Receptores da Bombesina/genética , Receptores da Bombesina/metabolismo , Peptídeo Liberador de Gastrina/genética , Peptídeo Liberador de Gastrina/metabolismo , Medula Espinal/metabolismo , Ácido Glutâmico/metabolismo , Dopamina/metabolismo , Prurido/genética , Prurido/metabolismo , Neurônios Dopaminérgicos/metabolismo , Receptores de AMPA/genética , Receptores de AMPA/metabolismo
13.
Proc Natl Acad Sci U S A ; 119(4)2022 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-35046043

RESUMO

Receptor usage defines cell tropism and contributes to cell entry and infection. Coxsackievirus B (CVB) engages coxsackievirus and adenovirus receptor (CAR), and selectively utilizes the decay-accelerating factor (DAF; CD55) to infect cells. However, the differential receptor usage mechanism for CVB remains elusive. This study identified VP3-234 residues (234Q/N/V/D/E) as critical population selection determinants during CVB3 virus evolution, contributing to diverse binding affinities to CD55. Cryoelectron microscopy (cryo-EM) structures of CD55-binding/nonbinding isolates and their complexes with CD55 or CAR were obtained under both neutral and acidic conditions, and the molecular mechanism of VP3-234 residues determining CD55 affinity/specificity for naturally occurring CVB3 strains was elucidated. Structural and biochemical studies in vitro revealed the dynamic entry process of CVB3 and the function of the uncoating receptor CAR with different pH preferences. This work provides detailed insight into the molecular mechanism of CVB infection and contributes to an in-depth understanding of enterovirus attachment receptor usage.


Assuntos
Antígenos CD55/metabolismo , Infecções por Coxsackievirus/metabolismo , Infecções por Coxsackievirus/virologia , Enterovirus Humano B/fisiologia , Interações Hospedeiro-Patógeno , Receptores Virais/metabolismo , Sequência de Aminoácidos , Substituição de Aminoácidos , Sítios de Ligação , Enterovirus Humano B/ultraestrutura , Humanos , Modelos Moleculares , Ligação Proteica , Conformação Proteica , Domínios e Motivos de Interação entre Proteínas , Receptores Virais/química , Relação Estrutura-Atividade , Ligação Viral
14.
Chem Soc Rev ; 53(3): 1375-1446, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38117181

RESUMO

The excessive consumption of fossil fuels causes massive emission of CO2, leading to climate deterioration and environmental pollution. The development of substitutes and sustainable energy sources to replace fossil fuels has become a worldwide priority. Bio-electrochemical systems (BESs), employing redox reactions of electroactive microorganisms (EAMs) on electrodes to achieve a meritorious combination of biocatalysis and electrocatalysis, provide a green and sustainable alternative approach for bioremediation, CO2 fixation, and energy and chemicals production. EAMs, including exoelectrogens and electrotrophs, perform extracellular electron transfer (EET) (i.e., outward and inward EET), respectively, to exchange energy with the environment, whose rate determines the efficiency and performance of BESs. Therefore, we review the synthetic biology strategies developed in the last decade for engineering EAMs to enhance the EET rate in cell-electrode interfaces for facilitating the production of electricity energy and value-added chemicals, which include (1) progress in genetic manipulation and editing tools to achieve the efficient regulation of gene expression, knockout, and knockdown of EAMs; (2) synthetic biological engineering strategies to enhance the outward EET of exoelectrogens to anodes for electricity power production and anodic electro-fermentation (AEF) for chemicals production, including (i) broadening and strengthening substrate utilization, (ii) increasing the intracellular releasable reducing equivalents, (iii) optimizing c-type cytochrome (c-Cyts) expression and maturation, (iv) enhancing conductive nanowire biosynthesis and modification, (v) promoting electron shuttle biosynthesis, secretion, and immobilization, (vi) engineering global regulators to promote EET rate, (vii) facilitating biofilm formation, and (viii) constructing cell-material hybrids; (3) the mechanisms of inward EET, CO2 fixation pathway, and engineering strategies for improving the inward EET of electrotrophic cells for CO2 reduction and chemical production, including (i) programming metabolic pathways of electrotrophs, (ii) rewiring bioelectrical circuits for enhancing inward EET, and (iii) constructing microbial (photo)electrosynthesis by cell-material hybridization; (4) perspectives on future challenges and opportunities for engineering EET to develop highly efficient BESs for sustainable energy and chemical production. We expect that this review will provide a theoretical basis for the future development of BESs in energy harvesting, CO2 fixation, and chemical synthesis.


Assuntos
Fontes de Energia Bioelétrica , Biologia Sintética , Elétrons , Dióxido de Carbono , Transporte de Elétrons , Combustíveis Fósseis , Eletrodos
15.
Nano Lett ; 24(15): 4354-4361, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38563599

RESUMO

The recent focus of cancer therapeutics research revolves around modulating the immunosuppressive tumor microenvironment (TME) to enhance efficacy. The tumor stroma, primarily composed of cancer-associated fibroblasts (CAFs), poses significant obstacles to therapeutic penetration, influencing resistance and tumor progression. Reprogramming CAFs into an inactivated state has emerged as a promising strategy, necessitating innovative approaches. This study pioneers the design of a nanoformulation using pioglitazone, a Food and Drug Administration-approved anti-diabetic drug, to reprogram CAFs in the breast cancer TME. Glutathione (GSH)-responsive dendritic mesoporous organosilica nanoparticles loaded with pioglitazone (DMON-P) are designed for the delivery of cargo to the GSH-rich cytosol of CAFs. DMON-P facilitates pioglitazone-mediated CAF reprogramming, enhancing the penetration of doxorubicin (Dox), a therapeutic drug. Treatment with DMON-P results in the downregulation of CAF biomarkers and inhibits tumor growth through the effective delivery of Dox. This innovative approach holds promise as an alternative strategy for enhancing therapeutic outcomes in CAF-abundant tumors, particularly in breast cancer.


Assuntos
Neoplasias da Mama , Fibroblastos Associados a Câncer , Nanopartículas , Humanos , Feminino , Pioglitazona/farmacologia , Pioglitazona/uso terapêutico , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Microambiente Tumoral
16.
Nano Lett ; 24(11): 3448-3455, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38452056

RESUMO

Unlike graphene derived from graphite, borophenes represent a distinct class of synthetic two-dimensional materials devoid of analogous bulk-layered allotropes, leading to covalent bonding within borophenes instead of van der Waals (vdW) stacking. Our investigation focuses on 665 vdW-stacking boron bilayers to uncover potential bulk-layered boron allotropes through vdW stacking. Systematic high-throughput screening and stability analysis reveal a prevailing inclination toward covalently bonded layers in the majority of boron bilayers. However, an intriguing outlier emerges in δ5 borophene, demonstrating potential as a vdW-stacking candidate. We delve into electronic and topological structural similarities between δ5 borophene and graphene, shedding light on the structural integrity and stability of vdW-stacked boron structures across bilayers, multilayers, and bulk-layered allotropes. The δ5 borophene analogues exhibit metallic properties and characteristics of phonon-mediated superconductors, boasting a critical temperature near 22 K. This study paves the way for the concept of "borophite", a long-awaited boron analogue of graphite.

17.
J Cell Mol Med ; 28(9): e18351, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38693854

RESUMO

Coronary artery bypass grafting (CABG) is an effective treatment for coronary heart disease, with vascular transplantation as the key procedure. Intimal hyperplasia (IH) gradually leads to vascular stenosis, seriously affecting the curative effect of CABG. Mesenchymal stem cells (MSCs) were used to alleviate IH, but the effect was not satisfactory. This work aimed to investigate whether lncRNA MIR155HG could improve the efficacy of MSCs in the treatment of IH and to elucidate the role of the competing endogenous RNA (ceRNA). The effect of MIR155HG on MSCs function was investigated, while the proteins involved were assessed. IH was detected by HE and Van Gieson staining. miRNAs as the target of lncRNA were selected by bioinformatics analysis. qRT-PCR and dual-luciferase reporter assay were performed to verify the binding sites of lncRNA-miRNA. The apoptosis, Elisa and tube formation assay revealed the effect of ceRNA on the endothelial protection of MIR155HG-MSCs. We observed that MIR155HG improved the effect of MSCs on IH by promoting viability and migration. MIR155HG worked as a sponge for miR-205. MIR155HG/miR-205 significantly improved the function of MSCs, avoiding apoptosis and inducing angiogenesis. The improved therapeutic effects of MSCs on IH might be due to the ceRNA role of MIR155HG/miR-205.


Assuntos
Apoptose , Hiperplasia , Células-Tronco Mesenquimais , MicroRNAs , RNA Longo não Codificante , Animais , Humanos , Apoptose/genética , Movimento Celular/genética , Proliferação de Células/genética , Sobrevivência Celular/genética , Regulação da Expressão Gênica , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Endógeno Competitivo , RNA Longo não Codificante/genética , Túnica Íntima/patologia , Túnica Íntima/metabolismo , Ratos
18.
J Am Chem Soc ; 146(7): 4333-4339, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38324359

RESUMO

Ru/Cu dual catalysis has been applied for Z-retentive asymmetric allylic substitution reactions of aldimine esters. This reaction provides an enantioselective synthesis of chiral Z-olefins in high yields (up to 91% yield) with excellent enantioselectivity (up to 98% ee) under mild conditions. The previously unreacted trisubstituted allylic electrophiles under Ir catalytic system are found to be compatible, affording the stereoretentive products in either Z- or E-form. Both linear and branched allylic electrophiles are suitable substrates with excellent reaction outcomes. Notably, Ru and Cu complexes are added in one-pot and simplifies the manipulation of this protocol and self-sorting phenomena could be observed in this Ru/Cu dual catalytic system.

19.
J Am Chem Soc ; 146(10): 6530-6535, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38410847

RESUMO

Thermal quenching (TQ) has been naturally entangling with luminescence since its discovery, and lattice vibration, which is characterized as multiphonon relaxation (MPR), plays a critical role. Considering that MPR may be suppressed under exterior pressure, we have designed a core/shell upconversion luminescence (UCL) system of α-NaYF4:Yb/Ln@ScF3 (Ln = Ho, Er, and Tm) with positive/negative thermal expansion behavior so that positive thermal expansion of the core will be restrained by negative thermal expansion of the shell when heated. This imposed pressure on the crystal lattice of the core suppresses MPR, reduces the amount of energy depleted by TQ, and eventually saves more energy for luminescing, so that anti-TQ or even thermally enhanced UCL is obtained.

20.
Apoptosis ; 2024 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-39068623

RESUMO

Malignant melanoma (MM) is a highly invasive and therapeutically resistant skin malignancy, posing a significant clinical challenge in its treatment. Programmed cell death plays a crucial role in the occurrence and progression of MM. Sphingolipids (SP), as a class of bioactive lipids, may be associated with many kinds of diseases. SPs regulate various forms of programmed cell death in tumors, including apoptosis, necroptosis, ferroptosis, and more. This review will delve into the mechanisms by which different types of SPs modulate various forms of programmed cell death in MM, such as their regulation of cell membrane permeability and signaling pathways, and how they influence the survival and death fate of MM cells. An in-depth exploration of the role of SPs in programmed cell death in MM aids in unraveling the molecular mechanisms of melanoma development and holds significant importance in developing novel therapeutic strategies.

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