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1.
Nature ; 631(8019): 60-66, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38867046

RESUMO

Broken time-reversal symmetry in the absence of spin order indicates the presence of unusual phases such as orbital magnetism and loop currents1-4. The recently discovered kagome superconductors AV3Sb5 (where A is K, Rb or Cs)5,6 display an exotic charge-density-wave (CDW) state and have emerged as a strong candidate for materials hosting a loop current phase. The idea that the CDW breaks time-reversal symmetry7-14 is, however, being intensely debated due to conflicting experimental data15-17. Here we use laser-coupled scanning tunnelling microscopy to study RbV3Sb5. By applying linearly polarized light along high-symmetry directions, we show that the relative intensities of the CDW peaks can be reversibly switched, implying a substantial electro-striction response, indicative of strong nonlinear electron-phonon coupling. A similar CDW intensity switching is observed with perpendicular magnetic fields, which implies an unusual piezo-magnetic response that, in turn, requires time-reversal symmetry breaking. We show that the simplest CDW that satisfies these constraints is an out-of-phase combination of bond charge order and loop currents that we dub a congruent CDW flux phase. Our laser scanning tunnelling microscopy data open the door to the possibility of dynamic optical control of complex quantum phenomenon in correlated materials.


Assuntos
Supercondutividade , Microscopia de Tunelamento , Campos Magnéticos , Fônons , Elétrons , Luz
2.
Nature ; 631(8020): 459-466, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38776963

RESUMO

Bitter taste receptors, particularly TAS2R14, play central roles in discerning a wide array of bitter substances, ranging from dietary components to pharmaceutical agents1,2. TAS2R14 is also widely expressed in extragustatory tissues, suggesting its extra roles in diverse physiological processes and potential therapeutic applications3. Here we present cryogenic electron microscopy structures of TAS2R14 in complex with aristolochic acid, flufenamic acid and compound 28.1, coupling with different G-protein subtypes. Uniquely, a cholesterol molecule is observed occupying what is typically an orthosteric site in class A G-protein-coupled receptors. The three potent agonists bind, individually, to the intracellular pockets, suggesting a distinct activation mechanism for this receptor. Comprehensive structural analysis, combined with mutagenesis and molecular dynamic simulation studies, elucidate the broad-spectrum ligand recognition and activation of the receptor by means of intricate multiple ligand-binding sites. Our study also uncovers the specific coupling modes of TAS2R14 with gustducin and Gi1 proteins. These findings should be instrumental in advancing knowledge of bitter taste perception and its broader implications in sensory biology and drug discovery.


Assuntos
Ácidos Aristolóquicos , Colesterol , Ácido Flufenâmico , Receptores Acoplados a Proteínas G , Paladar , Humanos , Ácidos Aristolóquicos/metabolismo , Ácidos Aristolóquicos/química , Ácidos Aristolóquicos/farmacologia , Sítios de Ligação/efeitos dos fármacos , Colesterol/química , Colesterol/metabolismo , Colesterol/farmacologia , Microscopia Crioeletrônica , Ácido Flufenâmico/química , Ácido Flufenâmico/metabolismo , Ácido Flufenâmico/farmacologia , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/química , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/metabolismo , Ligantes , Modelos Moleculares , Simulação de Dinâmica Molecular , Mutação , Receptores Acoplados a Proteínas G/agonistas , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Receptores Acoplados a Proteínas G/ultraestrutura , Paladar/efeitos dos fármacos , Paladar/fisiologia , Transducina/química , Transducina/metabolismo
3.
EMBO J ; 43(14): 3044-3071, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38858601

RESUMO

MCM8 has emerged as a core gene in reproductive aging and is crucial for meiotic homologous recombination repair. It also safeguards genome stability by coordinating the replication stress response during mitosis, but its function in mitotic germ cells remains elusive. Here we found that disabling MCM8 in mice resulted in proliferation defects of primordial germ cells (PGCs) and ultimately impaired fertility. We further demonstrated that MCM8 interacted with two known helicases DDX5 and DHX9, and loss of MCM8 led to R-loop accumulation by reducing the retention of these helicases at R-loops, thus inducing genome instability. Cells expressing premature ovarian insufficiency-causative mutants of MCM8 with decreased interaction with DDX5 displayed increased R-loop levels. These results show MCM8 interacts with R-loop-resolving factors to prevent R-loop-induced DNA damage, which may contribute to the maintenance of genome integrity of PGCs and reproductive reserve establishment. Our findings thus reveal an essential role for MCM8 in PGC development and improve our understanding of reproductive aging caused by genome instability in mitotic germ cells.


Assuntos
RNA Helicases DEAD-box , Instabilidade Genômica , Proteínas de Manutenção de Minicromossomo , Estruturas R-Loop , Animais , Feminino , Humanos , Masculino , Camundongos , RNA Helicases DEAD-box/metabolismo , RNA Helicases DEAD-box/genética , Dano ao DNA , Células Germinativas/metabolismo , Proteínas de Manutenção de Minicromossomo/metabolismo , Proteínas de Manutenção de Minicromossomo/genética , Estruturas R-Loop/genética
4.
Am J Hum Genet ; 111(8): 1736-1749, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39053459

RESUMO

Mendelian randomization (MR) provides valuable assessments of the causal effect of exposure on outcome, yet the application of conventional MR methods for mapping risk genes encounters new challenges. One of the issues is the limited availability of expression quantitative trait loci (eQTLs) as instrumental variables (IVs), hampering the estimation of sparse causal effects. Additionally, the often context- or tissue-specific eQTL effects challenge the MR assumption of consistent IV effects across eQTL and GWAS data. To address these challenges, we propose a multi-context multivariable integrative MR framework, mintMR, for mapping expression and molecular traits as joint exposures. It models the effects of molecular exposures across multiple tissues in each gene region, while simultaneously estimating across multiple gene regions. It uses eQTLs with consistent effects across more than one tissue type as IVs, improving IV consistency. A major innovation of mintMR involves employing multi-view learning methods to collectively model latent indicators of disease relevance across multiple tissues, molecular traits, and gene regions. The multi-view learning captures the major patterns of disease relevance and uses these patterns to update the estimated tissue relevance probabilities. The proposed mintMR iterates between performing a multi-tissue MR for each gene region and joint learning the disease-relevant tissue probabilities across gene regions, improving the estimation of sparse effects across genes. We apply mintMR to evaluate the causal effects of gene expression and DNA methylation for 35 complex traits using multi-tissue QTLs as IVs. The proposed mintMR controls genome-wide inflation and offers insights into disease mechanisms.


Assuntos
Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Locos de Características Quantitativas , Humanos , Análise da Randomização Mendeliana/métodos , Estudo de Associação Genômica Ampla/métodos , Especificidade de Órgãos/genética , Modelos Genéticos , Polimorfismo de Nucleotídeo Único
5.
Nat Methods ; 21(4): 623-634, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38504113

RESUMO

Single-cell proteomics sequencing technology sheds light on protein-protein interactions, posttranslational modifications and proteoform dynamics in the cell. However, the uncertainty estimation for peptide quantification, data missingness, batch effects and high noise hinder the analysis of single-cell proteomic data. It is important to solve this set of tangled problems together, but the existing methods tailored for single-cell transcriptomes cannot fully address this task. Here we propose a versatile framework designed for single-cell proteomics data analysis called scPROTEIN, which consists of peptide uncertainty estimation based on a multitask heteroscedastic regression model and cell embedding generation based on graph contrastive learning. scPROTEIN can estimate the uncertainty of peptide quantification, denoise protein data, remove batch effects and encode single-cell proteomic-specific embeddings in a unified framework. We demonstrate that scPROTEIN is efficient for cell clustering, batch correction, cell type annotation, clinical analysis and spatially resolved proteomic data exploration.


Assuntos
Aprendizagem , Proteômica , Análise por Conglomerados , Processamento de Proteína Pós-Traducional , Peptídeos
6.
Proc Natl Acad Sci U S A ; 121(10): e2312150121, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38412127

RESUMO

African swine fever, one of the major viral diseases of swine, poses an imminent threat to the global pig industry. The high-efficient replication of the causative agent African swine fever virus (ASFV) in various organs in pigs greatly contributes to the disease. However, how ASFV manipulates the cell population to drive high-efficient replication of the virus in vivo remains unclear. Here, we found that the spleen reveals the most severe pathological manifestation with the highest viral loads among various organs in pigs during ASFV infection. By using single-cell-RNA-sequencing technology and multiple methods, we determined that macrophages and monocytes are the major cell types infected by ASFV in the spleen, showing high viral-load heterogeneity. A rare subpopulation of immature monocytes represents the major population infected at late infection stage. ASFV causes massive death of macrophages, but shifts its infection into these monocytes which significantly arise after the infection. The apoptosis, interferon response, and antigen-presentation capacity are inhibited in these monocytes which benefits prolonged infection of ASFV in vivo. Until now, the role of immature monocytes as an important target by ASFV has been overlooked due to that they do not express classical monocyte marker CD14. The present study indicates that the shift of viral infection from macrophages to the immature monocytes is critical for maintaining prolonged ASFV infection in vivo. This study sheds light on ASFV tropism, replication, and infection dynamics, and elicited immune response, which may instruct future research on antiviral strategies.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Suínos , Animais , Vírus da Febre Suína Africana/fisiologia , Baço/patologia , Replicação Viral , Macrófagos/patologia
7.
J Biol Chem ; 300(8): 107516, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38960036

RESUMO

Focal segmental glomerulosclerosis (FSGS), a common cause of primary glomerulonephritis, has a poor prognosis and is pathologically featured by tubulointerstitial injury. Thrombospondin-1 (TSP-1) is an extracellular matrix protein that acts in combination with different receptors in the kidney. Here, we analyzed the tubular expression of TSP-1 and its receptor integrin ß3 (ITGB3) in FSGS. Previously the renal interstitial chip analysis of FSGS patients with tubular interstitial injury showed that the expression of TSP-1 and ITGB3 were upregulated. We found that the expression of TSP-1 and ITGB3 increased in the tubular cells of FSGS patients. The plasma level of TSP-1 increased and was correlated to the degree of tubulointerstitial lesions in FSGS patients. TSP-1/ITGB3 signaling induced renal tubular injury in HK-2 cells exposure to bovine serum albumin and the adriamycin (ADR)-induced nephropathy model. THBS1 KO ameliorated tubular injury and renal fibrosis in ADR-treated mice. THBS1 knockdown decreased the expression of KIM-1 and caspase 3 in the HK-2 cells treated with bovine serum albumin, while THBS1 overexpression could induce tubular injury. In vivo, we identified cyclo-RGDfK as an agent to block the binding of TSP-1 to ITGB3. Cyclo-RGDfK treatment could alleviate ADR-induced renal tubular injury and interstitial fibrosis in mice. Moreover, TSP-1 and ITGB3 were colocalized in tubular cells of FSGS patients and ADR-treated mice. Taken together, our data showed that TSP-1/ITGB3 signaling contributed to the development of renal tubulointerstitial injury in FSGS, potentially identifying a new therapeutic target for FSGS.

8.
Mol Biol Evol ; 41(1)2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38128148

RESUMO

The mosquito family Culicidae is divided into 2 subfamilies named the Culicinae and Anophelinae. Nix, the dominant male-determining factor, has only been found in the culicines Aedes aegypti and Aedes albopictus, 2 important arboviral vectors that belong to the subgenus Stegomyia. Here we performed sex-specific whole-genome sequencing and RNAseq of divergent mosquito species and explored additional male-inclusive datasets to investigate the distribution of Nix. Except for the Culex genus, Nix homologs were found in all species surveyed from the Culicinae subfamily, including 12 additional species from 3 highly divergent tribes comprising 4 genera, suggesting Nix originated at least 133 to 165 million years ago (MYA). Heterologous expression of 1 of 3 divergent Nix open reading frames (ORFs) in Ae. aegypti resulted in partial masculinization of genetic females as evidenced by morphology and doublesex splicing. Phylogenetic analysis suggests Nix is related to femaleless (fle), a recently described intermediate sex-determining factor found exclusively in anopheline mosquitoes. Nix from all species has a conserved structure, including 3 RNA-recognition motifs (RRMs), as does fle. However, Nix has evolved at a much faster rate than fle. The RRM3 of both Nix and fle are distantly related to the single RRM of a widely distributed and conserved splicing factor transformer-2 (tra2). The RRM3-based phylogenetic analysis suggests this domain in Nix and fle may have evolved from tra2 or a tra2-related gene in a common ancestor of mosquitoes. Our results provide insights into the evolution of sex determination in mosquitoes and will inform broad applications of mosquito-control strategies based on manipulating sex ratios toward nonbiting males.


Assuntos
Aedes , Mosquitos Vetores , Animais , Feminino , Masculino , Filogenia , Mosquitos Vetores/genética , Aedes/genética , Aedes/metabolismo , Splicing de RNA
9.
Gastroenterology ; 166(6): 1130-1144.e8, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38262581

RESUMO

BACKGROUND & AIMS: Despite the increasing number of treatment options available for liver cancer, only a small proportion of patients achieve long-term clinical benefits. Here, we aim to develop new therapeutic approaches for liver cancer. METHODS: A compound screen was conducted to identify inhibitors that could synergistically induce senescence when combined with cyclin-dependent kinase (CDK) 4/6 inhibitor. The combination effects of CDK4/6 inhibitor and exportin 1 (XPO1) inhibitor on cellular senescence were investigated in a panel of human liver cancer cell lines and multiple liver cancer models. A senolytic drug screen was performed to identify drugs that selectively killed senescent liver cancer cells. RESULTS: The combination of CDK4/6 inhibitor and XPO1 inhibitor synergistically induces senescence of liver cancer cells in vitro and in vivo. The XPO1 inhibitor acts by causing accumulation of RB1 in the nucleus, leading to decreased E2F signaling and promoting senescence induction by the CDK4/6 inhibitor. Through a senolytic drug screen, cereblon (CRBN)-based proteolysis targeting chimera (PROTAC) ARV-825 was identified as an agent that can selectively kill senescent liver cancer cells. Up-regulation of CRBN was a vulnerability of senescent liver cancer cells, making them sensitive to CRBN-based PROTAC drugs. Mechanistically, we find that ubiquitin specific peptidase 2 (USP2) directly interacts with CRBN, leading to the deubiquitination and stabilization of CRBN in senescent liver cancer cells. CONCLUSIONS: Our study demonstrates a striking synergy in senescence induction of liver cancer cells through the combination of CDK4/6 inhibitor and XPO1 inhibitor. These findings also shed light on the molecular processes underlying the vulnerability of senescent liver cancer cells to CRBN-based PROTAC therapy.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Senescência Celular , Quinase 4 Dependente de Ciclina , Quinase 6 Dependente de Ciclina , Proteína Exportina 1 , Carioferinas , Neoplasias Hepáticas , Inibidores de Proteínas Quinases , Receptores Citoplasmáticos e Nucleares , Ubiquitina-Proteína Ligases , Humanos , Senescência Celular/efeitos dos fármacos , Quinase 6 Dependente de Ciclina/antagonistas & inibidores , Quinase 6 Dependente de Ciclina/metabolismo , Quinase 4 Dependente de Ciclina/antagonistas & inibidores , Quinase 4 Dependente de Ciclina/metabolismo , Carioferinas/antagonistas & inibidores , Carioferinas/metabolismo , Receptores Citoplasmáticos e Nucleares/antagonistas & inibidores , Receptores Citoplasmáticos e Nucleares/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/metabolismo , Linhagem Celular Tumoral , Inibidores de Proteínas Quinases/farmacologia , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/antagonistas & inibidores , Animais , Proteínas de Ligação a Retinoblastoma/metabolismo , Proteínas de Ligação a Retinoblastoma/genética , Sinergismo Farmacológico , Senoterapia/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto , Transdução de Sinais/efeitos dos fármacos , Proteólise/efeitos dos fármacos , Hidrazinas/farmacologia , Hidrazinas/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Células Hep G2 , Camundongos , Piperazinas , Piridinas , Triazóis
10.
J Virol ; 98(3): e0000724, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38305153

RESUMO

Pseudorabies virus (PRV) is the causative agent of Aujeszky's disease, which is responsible for enormous economic losses to the global pig industry. Although vaccination has been used to prevent PRV infection, the effectiveness of vaccines has been greatly diminished with the emergence of PRV variants. Therefore, there is an urgent need to develop anti-PRV drugs. Polyethylenimine (PEI) is a cationic polymer and has a wide range of antibacterial and antiviral activities. This study found that a low dose of 1 µg/mL of the 25-kDa linear PEI had significantly specific anti-PRV activity, which became more intense with increasing concentrations. Mechanistic studies revealed that the viral adsorption stage was the major target of PEI without affecting viral entry, replication stages, and direct inactivation effects. Subsequently, we found that cationic polymers PEI and Polybrene interfered with the interaction between viral proteins and cell surface receptors through electrostatic interaction to exert the antiviral function. In conclusion, cationic polymers such as PEI can be a category of options for defense against PRV. Understanding the anti-PRV mechanism also deepens host-virus interactions and reveals new drug targets for anti-PRV.IMPORTANCEPolyethylenimine (PEI) is a cationic polymer that plays an essential role in the host immune response against microbial infections. However, the specific mechanisms of PEI in interfering with pseudorabies virus (PRV) infection remain unclear. Here, we found that 25-kDa linear PEI exerted mechanisms of antiviral activity and the target of its antiviral activity was mainly in the viral adsorption stage. Correspondingly, the study demonstrated that PEI interfered with the virus adsorption stage by electrostatic adsorption. In addition, we found that cationic polymers are a promising novel agent for controlling PRV, and its antiviral mechanism may provide a strategy for the development of antiviral drugs.


Assuntos
Antivirais , Herpesvirus Suídeo 1 , Polietilenoimina , Eletricidade Estática , Animais , Adsorção/efeitos dos fármacos , Antivirais/química , Antivirais/farmacologia , Herpesvirus Suídeo 1/efeitos dos fármacos , Herpesvirus Suídeo 1/metabolismo , Polietilenoimina/química , Polietilenoimina/farmacologia , Pseudorraiva/tratamento farmacológico , Pseudorraiva/virologia , Suínos/virologia , Doenças dos Suínos/virologia
11.
J Virol ; 98(7): e0058524, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-38869319

RESUMO

Senecavirus A (SVA), a picornavirus, causes vesicular diseases and epidemic transient neonatal losses in swine, resulting in a multifaceted economic impact on the swine industry. SVA counteracts host antiviral response through multiple strategies facilitatng viral infection and transmission. However, the mechanism of how SVA modulates interferon (IFN) response remains elusive. Here, we demonstrate that SVA 3C protease (3Cpro) blocks the transduction of Janus kinase-signal transducer and activator of transcription (JAK-STAT) signaling pathway to antagonize type I IFN response. Mechanistically, 3Cpro selectively cleaves and degrades STAT1 and STAT2 while does not target JAK1, JAK2, and IRF9, through its protease activity. Notably, SVA 3Cpro cleaves human and porcine STAT1 on a Leucine (L)-Aspartic acid (D) motif, specifically L693/D694. In the case of STAT2, two cleavage sites were identified: glutamine (Q) 707 was identified in both human and porcine, while the second cleavage pattern differed, with residues 754-757 (Valine-Leucine-Glutamine-Serine motifs) in human STAT2 and Q758 in porcine STAT2. These cleavage patterns by SVA 3Cpro partially differ from previously reported classical motifs recognized by other picornaviral 3Cpro, highlighting the distinct characteristics of SVA 3Cpro. Together, these results reveal a mechanism by which SVA 3Cpro antagonizes IFN-induced antiviral response but also expands our knowledge about the substrate recognition patterns for picornaviral 3Cpro.IMPORTANCESenecavirus A (SVA), the only member in the Senecavirus genus within the Picornaviridae family, causes vesicular diseases in pigs that are clinically indistinguishable from foot-and-mouth disease (FMD), a highly contagious viral disease listed by the World Organization for Animal Health (WOAH). Interferon (IFN)-mediated antiviral response plays a pivotal role in restricting and controlling viral infection. Picornaviruses evolved numerous strategies to antagonize host antiviral response. However, how SVA modulates the JAK-STAT signaling pathway, influencing the type I IFN response, remains elusive. Here, we identify that 3Cpro, a protease of SVA, functions as an antagonist for the IFN response. 3Cpro utilizes its protease activity to cleave STAT1 and STAT2, thereby diminishing the host IFN response to promote SVA infection. Our findings underscore the significance of 3Cpro as a key virulence factor in the antagonism of the type I signaling pathway during SVA infection.


Assuntos
Cisteína Endopeptidases , Infecções por Picornaviridae , Picornaviridae , Fator de Transcrição STAT1 , Fator de Transcrição STAT2 , Transdução de Sinais , Proteínas Virais , Animais , Suínos , Fator de Transcrição STAT2/metabolismo , Humanos , Infecções por Picornaviridae/virologia , Infecções por Picornaviridae/imunologia , Infecções por Picornaviridae/metabolismo , Fator de Transcrição STAT1/metabolismo , Cisteína Endopeptidases/metabolismo , Proteínas Virais/metabolismo , Proteases Virais 3C , Doenças dos Suínos/virologia , Doenças dos Suínos/imunologia , Células HEK293 , Interferon Tipo I/antagonistas & inibidores , Interferon Tipo I/metabolismo , Linhagem Celular , Janus Quinases/metabolismo , Janus Quinases/antagonistas & inibidores
12.
FASEB J ; 38(1): e23342, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38038724

RESUMO

Human antigen R (HuR) is a universally expressed RNA-binding protein that plays an essential role in governing the fate of mRNA transcripts. Accumulating evidence indicated that HuR is involved in the development and functions of several cell types. However, its role in cerebral ischemia/reperfusion injury (CIRI) remains unclear. In this study, we found that HuR was significantly upregulated after CIRI. Moreover, we found that silencing HuR could inhibit the inflammatory response of microglia and reduce the damage to neurons caused by oxygen-glucose deprivation/reperfusion treatment. In vivo, we found that microglial HuR deficiency significantly ameliorated CIRI and reduced NLRP3-mediated inflammasome activation. Mechanistically, we found that HuR could regulate NLRP3 mRNA stability by binding to the AU-rich element (ARE) region within the 3' untranslated region (UTR) of NLRP3 mRNA. In addition, we found that the upregulation of HuR was dependent on the upregulation of NADPH oxidase-mediated ROS accumulation. Collectively, our studies revealed that HuR could regulate NLRP3 expression and that HuR deficiency abrogated the enhanced NLRP3 signaling in experimental ischemic stroke. Targeting HuR may be a novel therapeutic strategy for cerebral ischemic stroke treatment.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Traumatismo por Reperfusão , Isquemia Encefálica/metabolismo , Inflamassomos/metabolismo , AVC Isquêmico/genética , AVC Isquêmico/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/metabolismo , RNA Mensageiro , Transdução de Sinais , Animais
13.
FASEB J ; 38(1): e23368, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38100644

RESUMO

The uterine contraction during labor, a process with repetitive hypoxia and high energy consumption, is essential for successful delivery. However, the molecular mechanism of myometrial contraction regulation is unknown. Serpin family E member 1 (SERPINE1), one of the most upregulated genes in laboring myometrium in both transcriptome and proteome, was highlighted in our previous study. Here, we confirmed SERPINE1 is upregulated in myometrium during labor. Blockade of SERPINE1 using small interfering RNA (siRNA) or inhibitor (Tiplaxtinin) under hypoxic conditions in myocytes or myometrium in vitro showed a decrease contractility, which was achieved by regulating ATP production. Chromatin immunoprecipitation (ChIP-seq), Co-immunoprecipitation (Co-IP), and glutathione-S-transferase (GST) pull down explored that the promoter of SERPINE1 is directly activated by hypoxia-inducible factor-1α (HIF-1α) and SERPINE1 interacts with ATP Synthase Peripheral Stalk Subunit F6 (ATP5PF). Together they enhance hypoxia driven myometrial contraction by maintaining ATP production in the key oxidative phosphorylation pathway. The results provide new insight for uterine contraction regulation, and potential novel therapeutic targets for labor management.


Assuntos
Trabalho de Parto , Serpinas , Gravidez , Feminino , Humanos , Serpinas/metabolismo , Miométrio/metabolismo , Contração Uterina , RNA Interferente Pequeno/metabolismo , Hipóxia/metabolismo , Trifosfato de Adenosina/metabolismo
14.
J Pathol ; 262(4): 517-528, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38361487

RESUMO

This study aimed to provide more information for prognostic stratification for patients through an analysis of the T-cell spatial landscape. It involved analyzing stained tissue sections of 80 patients with stage III lung adenocarcinoma (LUAD) using multiplex immunofluorescence and exploring the spatial landscape of T cells and their relationship with prognosis in the center of the tumor (CT) and invasive margin (IM). In this study, multivariate regression suggested that the relative clustering of CT CD4+ conventional T cell (Tconv) to inducible Treg (iTreg), natural regulatory T cell (nTreg) to Tconv, terminal CD8+ T cell (tCD8) to helper T cell (Th), and IM Treg to tCD8 and the relative dispersion of CT nTreg to iTreg, IM nTreg to nTreg were independent risk factors for DFS. Finally, we constructed a spatial immunological score named the GT score, which had stronger prognostic correlation than IMMUNOSCORE® based on CD3/CD8 cell densities. The spatial layout of T cells in the tumor microenvironment and the proposed GT score can reflect the prognosis of patients with stage III LUAD more effectively than T-cell density. The exploration of the T-cell spatial landscape may suggest potential cell-cell interactions and therapeutic targets and better guide clinical decision-making. © 2024 The Pathological Society of Great Britain and Ireland.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Humanos , Linfócitos T CD8-Positivos , Linfócitos T Reguladores , Prognóstico , Adenocarcinoma de Pulmão/patologia , Reino Unido , Microambiente Tumoral , Neoplasias Pulmonares/patologia
15.
BMC Biol ; 22(1): 169, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39135045

RESUMO

BACKGROUND: Numerous insect species undertake long-distance migrations on an enormous scale, with great implications for ecosystems. Given that take-off is the point where it all starts, whether and how the external light and internal circadian rhythm are involved in regulating the take-off behaviour remains largely unknown. Herein, we explore this issue in a migratory pest, Cnaphalocrocis medinalis, via behavioural observations and RNAi experiments. RESULTS: The results showed that C. medinalis moths took off under conditions where the light intensity gradually weakened to 0.1 lx during the afternoon or evening, and the take-off proportions under full spectrum or blue light were significantly higher than that under red and green light. The ultraviolet-A/blue light-sensitive type 1 cryptochrome gene (Cmedcry1) was significantly higher in take-off moths than that of non-take-off moths. In contrast, the expression of the light-insensitive CRY2 (Cmedcry2) and circadian genes (Cmedtim and Cmedper) showed no significant differences. After silencing Cmedcry1, the take-off proportion significantly decreased. Thus, Cmedcry1 is involved in the decrease in light intensity induced take-off behaviour in C. medinalis. CONCLUSIONS: This study can help further explain the molecular mechanisms behind insect migration, especially light perception and signal transmission during take-off phases.


Assuntos
Criptocromos , Proteínas de Insetos , Mariposas , Animais , Migração Animal , Ritmo Circadiano , Criptocromos/genética , Criptocromos/metabolismo , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Luz , Mariposas/fisiologia , Interferência de RNA
16.
Nano Lett ; 24(13): 3952-3960, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38527956

RESUMO

Despite light-emitting diodes (LEDs) based on quasi-two-dimensional (Q-2D) perovskites being inexpensive and exhibiting high performance, defects still limit the improvement of electroluminescence efficiency and stability by causing nonradiative recombination. Here, an organic molecule, 1-(o-tolyl) biguanide, is used to simultaneously inhibit and passivate defects of Q-2D perovskites via in situ synchronous crystallization. This molecule not only prevents surface bromine vacancies from forming through hydrogen bonding with the bromine of intermediaries but also passivates surface defects through its interaction with uncoordinated Pb. Via combination of defect inhibition and passivation, the trap density of Q-2D perovskite films can be significantly reduced, and the emission efficiency of the film can be improved. Consequently, the corresponding LED shows an external quantum efficiency of 24.3%, and its operational stability has been increased nearly 15 times.

17.
Nano Lett ; 24(22): 6805-6812, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38787360

RESUMO

Near-field enhanced mid-infrared light-matter interactions via metallic plasmonic antennae (PA) have attracted much attention but are inevitably limited by the detuning between their narrow band and the broad applied spectral range. Here, we develop a new low-temperature incubation synthetic method to acquire uniform Ag microparticles (MPs) with numerous hotspots. Their plasmonic band is remarkably extended by the plasmonic coupling of numerous hotspots and covers the entire mid-infrared range (400-4000 cm-1). Hence, the almost complete molecular fingerprint of 4-mercaptobenzonitrile was successfully probed for the first time via resonant surface-enhanced infrared absorption (rSEIRA), and the rSEIRA spectra of different essential amino acids were further detected and exhibit a high spectral identification degree assisted by machine learning. This work changes the inertia perception of "narrow band and large size but small hotspot area" of mid-infrared metallic PA and paves the way for the ultrasensitive mid-infrared optical sensing.

18.
Nano Lett ; 24(23): 7012-7018, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38820129

RESUMO

Light management is critical to maximizing the external quantum efficiency of perovskite light-emitting diodes (PeLEDs), but strategies for enhancing light out-coupling are typically complex and expensive. Here, using a facile solvent treatment strategy, we create a layer of lithium fluoride (LiF) nanoislands that serve as a template to reconstruct the light-extracting interfaces for PeLEDs. The nanoisland interface rearranges the near-field light distribution in order to maximize the efficiency of internal light extraction. With the proper adjustment of the nanoisland size and distribution, we have achieved an optimal balance between charge injection and light out-coupling, resulting in bright, pure-red quasi-two-dimensional PeLEDs with a 21.8% peak external quantum efficiency.

19.
Nano Lett ; 24(1): 433-440, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38112415

RESUMO

Coordinating multiple artificial cellular compartments into a well-organized artificial multicellular system (AMS) is of great interest in bottom-up synthetic biology. However, developing a facile strategy for fabricating an AMS with a controlled arrangement remains a challenge. Herein, utilizing in situ DNA hybridization chain reaction on the membrane surface, we developed a DNA patch-based strategy to direct the interconnection of vesicles. By tuning the DNA patch that generates heterotrophic adhesion for the attachment of vesicles, we could produce an AMS with higher-order structures straightforwardly and effectively. Furthermore, a hybrid AMS comprising live cells and vesicles was fabricated, and we found the hybrid AMS with higher-order structures arouses efficient molecular transportation from vesicles to living cells. In brief, our work provides a versatile strategy for modulating the self-assembly of AMSs, which could expand our capability to engineer synthetic biological systems and benefit synthetic cell research in programmable manipulation of intercellular communications.


Assuntos
Células Artificiais , Fenômenos Biológicos , Membranas/química , DNA/química , Células Artificiais/química , Biologia Sintética
20.
Nano Lett ; 24(12): 3793-3800, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38484388

RESUMO

Plasmonic superstructures hold great potential in encrypted information chips but are still unsatisfactory in terms of resolution and maneuverability because of the limited fabrication strategies. Here, we develop an antielectric potential method in which the interfacial energy from the modification of 5-amino-2-mercapto benzimidazole (AMBI) ligand is used to overcome the electric resistance between the Au nanospheres (NSs) and substrate, thereby realizing the in situ growth of a Au-Ag heterodimers array in large scale. The morphology, number, and size of Ag domains on Au units can be controlled well by modulating the reaction kinetics and thermodynamics. Experiments and theoretical simulations reveal that patterned 3D Au-2D Ag and 3D Au-3D Ag dimer arrays with line widths of 400 nm exhibit cerulean and cyan colors, respectively, and achieve fine color modulation and ultrahigh information resolution. This work not only develops a facile strategy for fabricating patterned plasmonic superstructures but also pushes the plasmon-based high-resolution encrypted information chip into more complex applications.

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