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1.
Cell ; 184(9): 2362-2371.e9, 2021 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-33735608

RESUMO

The 501Y.V2 variants of SARS-CoV-2 containing multiple mutations in spike are now dominant in South Africa and are rapidly spreading to other countries. Here, experiments with 18 pseudotyped viruses showed that the 501Y.V2 variants do not confer increased infectivity in multiple cell types except for murine ACE2-overexpressing cells, where a substantial increase in infectivity was observed. Notably, the susceptibility of the 501Y.V2 variants to 12 of 17 neutralizing monoclonal antibodies was substantially diminished, and the neutralization ability of the sera from convalescent patients and immunized mice was also reduced for these variants. The neutralization resistance was mainly caused by E484K and N501Y mutations in the receptor-binding domain of spike. The enhanced infectivity in murine ACE2-overexpressing cells suggests the possibility of spillover of the 501Y.V2 variants to mice. Moreover, the neutralization resistance we detected for the 501Y.V2 variants suggests the potential for compromised efficacy of monoclonal antibodies and vaccines.


Assuntos
COVID-19/imunologia , COVID-19/virologia , Evasão da Resposta Imune , SARS-CoV-2/patogenicidade , Enzima de Conversão de Angiotensina 2/metabolismo , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Antígenos Virais/imunologia , Linhagem Celular Tumoral , Células HEK293 , Humanos , Mutação/genética , SARS-CoV-2/genética
2.
Cell ; 182(5): 1284-1294.e9, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32730807

RESUMO

The spike protein of SARS-CoV-2 has been undergoing mutations and is highly glycosylated. It is critically important to investigate the biological significance of these mutations. Here, we investigated 80 variants and 26 glycosylation site modifications for the infectivity and reactivity to a panel of neutralizing antibodies and sera from convalescent patients. D614G, along with several variants containing both D614G and another amino acid change, were significantly more infectious. Most variants with amino acid change at receptor binding domain were less infectious, but variants including A475V, L452R, V483A, and F490L became resistant to some neutralizing antibodies. Moreover, the majority of glycosylation deletions were less infectious, whereas deletion of both N331 and N343 glycosylation drastically reduced infectivity, revealing the importance of glycosylation for viral infectivity. Interestingly, N234Q was markedly resistant to neutralizing antibodies, whereas N165Q became more sensitive. These findings could be of value in the development of vaccine and therapeutic antibodies.


Assuntos
Antígenos Virais/genética , Betacoronavirus/patogenicidade , Mutação , Glicoproteína da Espícula de Coronavírus/genética , Células A549 , Animais , Antígenos Virais/imunologia , Betacoronavirus/genética , Betacoronavirus/imunologia , Sítios de Ligação , Bovinos , Chlorocebus aethiops , Cricetinae , Cães , Glicosilação , Células HEK293 , Células HeLa , Humanos , Macaca mulatta , Células Madin Darby de Rim Canino , Camundongos , Células RAW 264.7 , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/metabolismo , Suínos , Células Vero , Virulência/genética
3.
Nat Immunol ; 23(10): 1433-1444, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36138184

RESUMO

Naive T cells undergo radical changes during the transition from dormant to hyperactive states upon activation, which necessitates de novo protein production via transcription and translation. However, the mechanism whereby T cells globally promote translation remains largely unknown. Here, we show that on exit from quiescence, T cells upregulate transfer RNA (tRNA) m1A58 'writer' proteins TRMT61A and TRMT6, which confer m1A58 RNA modification on a specific subset of early expressed tRNAs. These m1A-modified early tRNAs enhance translation efficiency, enabling rapid and necessary synthesis of MYC and of a specific group of key functional proteins. The MYC protein then guides the exit of naive T cells from a quiescent state into a proliferative state and promotes rapid T cell expansion after activation. Conditional deletion of the Trmt61a gene in mouse CD4+ T cells causes MYC protein deficiency and cell cycle arrest, disrupts T cell expansion upon cognate antigen stimulation and alleviates colitis in a mouse adoptive transfer colitis model. Our study elucidates for the first time, to our knowledge, the in vivo physiological roles of tRNA-m1A58 modification in T cell-mediated pathogenesis and reveals a new mechanism of tRNA-m1A58-controlled T cell homeostasis and signal-dependent translational control of specific key proteins.


Assuntos
Colite , RNA de Transferência , Transferência Adotiva , Animais , Proliferação de Células/genética , Colite/genética , Camundongos , Biossíntese de Proteínas , RNA de Transferência/genética , RNA de Transferência/metabolismo , Linfócitos T/metabolismo
4.
Mol Cell ; 84(15): 2984-3000.e8, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39002544

RESUMO

5-methylcytosine (m5C) is a prevalent RNA modification crucial for gene expression regulation. However, accurate and sensitive m5C sites identification remains challenging due to severe RNA degradation and reduced sequence complexity during bisulfite sequencing (BS-seq). Here, we report m5C-TAC-seq, a bisulfite-free approach combining TET-assisted m5C-to-f5C oxidation with selective chemical labeling, therefore enabling direct base-resolution m5C detection through pre-enrichment and C-to-T transitions at m5C sites. With m5C-TAC-seq, we comprehensively profiled the m5C methylomes in human and mouse cells, identifying a substantially larger number of confident m5C sites. Through perturbing potential m5C methyltransferases, we deciphered the responsible enzymes for most m5C sites, including the characterization of NSUN5's involvement in mRNA m5C deposition. Additionally, we characterized m5C dynamics during mESC differentiation. Notably, the mild reaction conditions and preservation of nucleotide composition in m5C-TAC-seq allow m5C detection in chromatin-associated RNAs. The accurate and robust m5C-TAC-seq will advance research into m5C methylation functional investigation.


Assuntos
5-Metilcitosina , Sulfitos , Transcriptoma , 5-Metilcitosina/metabolismo , 5-Metilcitosina/química , Animais , Humanos , Camundongos , Sulfitos/química , Metiltransferases/metabolismo , Metiltransferases/genética , Perfilação da Expressão Gênica/métodos , Diferenciação Celular
5.
Cell ; 150(3): 575-89, 2012 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-22863010

RESUMO

The mechanism by which cells decide to skip mitosis to become polyploid is largely undefined. Here we used a high-content image-based screen to identify small-molecule probes that induce polyploidization of megakaryocytic leukemia cells and serve as perturbagens to help understand this process. Our study implicates five networks of kinases that regulate the switch to polyploidy. Moreover, we find that dimethylfasudil (diMF, H-1152P) selectively increased polyploidization, mature cell-surface marker expression, and apoptosis of malignant megakaryocytes. An integrated target identification approach employing proteomic and shRNA screening revealed that a major target of diMF is Aurora kinase A (AURKA). We further find that MLN8237 (Alisertib), a selective inhibitor of AURKA, induced polyploidization and expression of mature megakaryocyte markers in acute megakaryocytic leukemia (AMKL) blasts and displayed potent anti-AMKL activity in vivo. Our findings provide a rationale to support clinical trials of MLN8237 and other inducers of polyploidization and differentiation in AMKL.


Assuntos
Azepinas/farmacologia , Descoberta de Drogas , Leucemia Megacarioblástica Aguda/tratamento farmacológico , Megacariócitos/metabolismo , Poliploidia , Pirimidinas/farmacologia , Bibliotecas de Moléculas Pequenas , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/análogos & derivados , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/farmacologia , Animais , Aurora Quinase A , Aurora Quinases , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Humanos , Leucemia Megacarioblástica Aguda/genética , Megacariócitos/citologia , Megacariócitos/patologia , Camundongos , Camundongos Endogâmicos C57BL , Mapas de Interação de Proteínas , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/metabolismo , Quinases Associadas a rho/metabolismo
6.
Nature ; 591(7848): 147-151, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33505025

RESUMO

Many sequence variants have been linked to complex human traits and diseases1, but deciphering their biological functions remains challenging, as most of them reside in noncoding DNA. Here we have systematically assessed the binding of 270 human transcription factors to 95,886 noncoding variants in the human genome using an ultra-high-throughput multiplex protein-DNA binding assay, termed single-nucleotide polymorphism evaluation by systematic evolution of ligands by exponential enrichment (SNP-SELEX). The resulting 828 million measurements of transcription factor-DNA interactions enable estimation of the relative affinity of these transcription factors to each variant in vitro and evaluation of the current methods to predict the effects of noncoding variants on transcription factor binding. We show that the position weight matrices of most transcription factors lack sufficient predictive power, whereas the support vector machine combined with the gapped k-mer representation show much improved performance, when assessed on results from independent SNP-SELEX experiments involving a new set of 61,020 sequence variants. We report highly predictive models for 94 human transcription factors and demonstrate their utility in genome-wide association studies and understanding of the molecular pathways involved in diverse human traits and diseases.


Assuntos
Polimorfismo de Nucleotídeo Único/genética , Técnica de Seleção de Aptâmeros , Máquina de Vetores de Suporte , Fatores de Transcrição/metabolismo , Sítios de Ligação/genética , Doença/genética , Genoma Humano/genética , Humanos , Ligantes , Ligação Proteica
7.
Circ Res ; 135(5): 596-613, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39056179

RESUMO

BACKGROUND: Macrophages are key players in obesity-associated cardiovascular diseases, which are marked by inflammatory and immune alterations. However, the pathophysiological mechanisms underlying macrophage's role in obesity-induced cardiac inflammation are incompletely understood. Our study aimed to identify the key macrophage population involved in obesity-induced cardiac dysfunction and investigate the molecular mechanism that contributes to the inflammatory response. METHODS: In this study, we used single-cell RNA-sequencing analysis of Cd45+CD11b+F4/80+ cardiac macrophages to explore the heterogeneity of cardiac macrophages. The CCR2+ (C-C chemokine receptor 2) macrophages were specifically removed by a dual recombinase approach, and the macrophage CCR2 was deleted to investigate their functions. We also performed cleavage under target and tagmentation analysis, chromatin immunoprecipitation-polymerase chain reaction, luciferase assay, and macrophage-specific lentivirus transfection to define the impact of lysozyme C in macrophages on obesity-induced inflammation. RESULTS: We find that the Ccr2 cluster undergoes a functional transition from homeostatic maintenance to proinflammation. Our data highlight specific changes in macrophage behavior during cardiac dysfunction under metabolic challenge. Consistently, inducible ablation of CCR2+CX3CR1+ macrophages or selective deletion of macrophage CCR2 prevents obesity-induced cardiac dysfunction. At the mechanistic level, we demonstrate that the obesity-induced functional shift of CCR2-expressing macrophages is mediated by the CCR2/activating transcription factor 3/lysozyme 1/NF-κB (nuclear factor kappa B) signaling. Finally, we uncover a noncanonical role for lysozyme 1 as a transcription activator, binding to the RelA promoter, driving NF-κB signaling, and strongly promoting inflammation and cardiac dysfunction in obesity. CONCLUSIONS: Our findings suggest that lysozyme 1 may represent a potential target for the diagnosis of obesity-induced inflammation and the treatment of obesity-induced heart disease.


Assuntos
Macrófagos , Muramidase , Obesidade , Receptores CCR2 , Animais , Obesidade/complicações , Obesidade/metabolismo , Macrófagos/metabolismo , Receptores CCR2/metabolismo , Receptores CCR2/genética , Camundongos , Muramidase/metabolismo , Muramidase/genética , Camundongos Endogâmicos C57BL , Masculino , Camundongos Knockout , Transdução de Sinais , Inflamação/metabolismo , Inflamação/genética , Cardiopatias/etiologia , Cardiopatias/metabolismo , Cardiopatias/genética
8.
J Virol ; 98(7): e0046724, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-38864621

RESUMO

Acinetobacter baumannii, an opportunistic pathogen, poses a significant threat in intensive care units, leading to severe nosocomial infections. The rise of multi-drug-resistant strains, particularly carbapenem-resistant A. baumannii, has created formidable challenges for effective treatment. Given the prolonged development cycle and high costs associated with antibiotics, phages have garnered clinical attention as an alternative for combating infections caused by drug-resistant bacteria. However, the utilization of phage therapy encounters notable challenges, including the narrow host spectrum, where each phage targets a limited subset of bacteria, increasing the risk of phage resistance development. Additionally, uncertainties in immune system dynamics during treatment hinder tailoring symptomatic interventions based on patient-specific states. In this study, we isolated two A. baumannii phages from wastewater and conducted a comprehensive assessment of their potential applications. This evaluation included sequencing analysis, genome classification, pH and temperature stability assessments, and in vitro bacterial inhibition assays. Further investigations involved analyzing histological and cytokine alterations in rats undergoing phage cocktail treatment for pneumonia. The therapeutic efficacy of the phages was validated, and transcriptomic studies of rat lung tissue during phage treatment revealed crucial changes in the immune system. The findings from our study underscore the potential of phages for future development as a treatment strategy and offer compelling evidence regarding immune system dynamics throughout the treatment process.IMPORTANCEDue to the growing problem of multi-drug-resistant bacteria, the use of phages is being considered as an alternative to antibiotics, and the genetic safety and application stability of phages determine the potential of phage application. The absence of drug resistance genes and virulence genes in the phage genome can ensure the safety of phage application, and the fact that phage can remain active in a wide range of temperatures and pH is also necessary for application. In addition, the effect evaluation of preclinical studies is especially important for clinical application. By simulating the immune response situation during the treatment process through mammalian models, the changes in animal immunity can be observed, and the effect of phage therapy can be further evaluated. Our study provides compelling evidence that phages hold promise for further development as therapeutic agents for Acinetobacter baumannii infections.


Assuntos
Infecções por Acinetobacter , Acinetobacter baumannii , Bacteriófagos , Carbapenêmicos , Modelos Animais de Doenças , Terapia por Fagos , Acinetobacter baumannii/virologia , Acinetobacter baumannii/efeitos dos fármacos , Animais , Infecções por Acinetobacter/terapia , Infecções por Acinetobacter/microbiologia , Ratos , Terapia por Fagos/métodos , Carbapenêmicos/farmacologia , Bacteriófagos/fisiologia , Bacteriófagos/genética , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Farmacorresistência Bacteriana Múltipla , Masculino , Genoma Viral , Águas Residuárias , Pneumonia/terapia , Pneumonia/microbiologia , Pneumonia/virologia
9.
Plant Physiol ; 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39268874

RESUMO

In arbuscular mycorrhizal (AM) symbiosis, appropriate regulation of the formation, maintenance, and degeneration of the arbuscule are essential for plants and fungi. In this study, we identified a Cysteine-2/Histidine-2 zinc finger protein (C2H2-ZFP)-encoding gene in Lotus japonicus named Regulator of Symbiosome Differentiation-Like (LjRSDL) that is required for arbuscule degeneration. Evolutionary analysis showed that homologs of LjRSDL exist in mycorrhizal flowering plants. We obtained ProLjRSDL::GUS transgenic hairy roots and showed that LjRSDL was strongly upregulated upon AM colonization, particularly at 18 days post AM fungi inoculation and specifically expressed in arbuscular-containing cells. The mycorrhization rate increased in the ljrsdl mutant but decreased in LjRSDL overexpressed L. japonicus. Interestingly, we observed higher proportions of large arbuscule in the ljrsdl mutant but lower proportions of larger arbuscule in LjRSDL overexpressing plants. Transcriptome analyses indicated that genes involved in arbuscule degeneration were significantly changed upon the dysregulation of LjRSDL and that LjRSDL-dependent regulation in AM symbiosis is mainly via the hormone signal transduction pathway. LjRSDL, therefore, represents a C2H2-ZFP that negatively regulates AM symbiosis. Our study provides insight into understanding plant-AM fungal communication and AM symbiosis development.

10.
FASEB J ; 38(16): e23884, 2024 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-39135512

RESUMO

The inhibition of the autophagolysosomal pathway mediated by transcription factor EB (TFEB) inactivation in proximal tubular epithelial cells (TECs) is a key mechanism of TEC injury in diabetic kidney disease (DKD). Acetylation is a novel mechanism that regulates TFEB activity. However, there are currently no studies on whether the adjustment of the acetylation level of TFEB can reduce the damage of diabetic TECs. In this study, we investigated the effect of Trichostatin A (TSA), a typical deacetylase inhibitor, on TFEB activity and damage to TECs in both in vivo and in vitro models of DKD. Here, we show that TSA treatment can alleviate the pathological damage of glomeruli and renal tubules and delay the DKD progression in db/db mice, which is associated with the increased expression of TFEB and its downstream genes. In vitro studies further confirmed that TSA treatment can upregulate the acetylation level of TFEB, promote its nuclear translocation, and activate the expression of its downstream genes, thereby reducing the apoptosis level of TECs. TFEB deletion or HDAC6 knockdown in TECs can counteract the activation effect of TSA on autophagolysosomal pathway. We also found that TFEB enhances the transcription of Tfeb through binding to its promoter and promotes its own expression. Our results, thus, provide a novel therapeutic mechanism for DKD that the alleviation of TEC damage by activating the autophagic lysosomal pathway through upregulating TFEB acetylation can, thus, delay DKD progression.


Assuntos
Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos , Nefropatias Diabéticas , Células Epiteliais , Inibidores de Histona Desacetilases , Ácidos Hidroxâmicos , Túbulos Renais Proximais , Animais , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Nefropatias Diabéticas/metabolismo , Camundongos , Acetilação , Células Epiteliais/metabolismo , Células Epiteliais/efeitos dos fármacos , Túbulos Renais Proximais/metabolismo , Túbulos Renais Proximais/patologia , Ácidos Hidroxâmicos/farmacologia , Inibidores de Histona Desacetilases/farmacologia , Masculino , Camundongos Endogâmicos C57BL , Autofagia/efeitos dos fármacos , Apoptose/efeitos dos fármacos
11.
EMBO Rep ; 24(9): e56512, 2023 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-37437058

RESUMO

Long interspersed element 1 (LINE-1) is the only active autonomous mobile element in the human genome. Its transposition can exert deleterious effects on the structure and function of the host genome and cause sporadic genetic diseases. Tight control of LINE-1 mobilization by the host is crucial for genetic stability. In this study, we report that MOV10 recruits the main decapping enzyme DCP2 to LINE-1 RNA and forms a complex of MOV10, DCP2, and LINE-1 RNP, exhibiting liquid-liquid phase separation (LLPS) properties. DCP2 cooperates with MOV10 to decap LINE-1 RNA, which causes degradation of LINE-1 RNA and thus reduces LINE-1 retrotransposition. We here identify DCP2 as one of the key effector proteins determining LINE-1 replication, and elucidate an LLPS mechanism that facilitates the anti-LINE-1 action of MOV10 and DCP2.


Assuntos
Grânulos Citoplasmáticos , RNA Helicases , Humanos , Grânulos Citoplasmáticos/metabolismo , Endorribonucleases/genética , Elementos Nucleotídeos Longos e Dispersos , RNA/metabolismo , RNA Helicases/metabolismo
12.
Exp Cell Res ; 437(1): 113998, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38513962

RESUMO

Plasma saturated free fatty acid (FFA)-induced endothelial dysfunction (ED) contributes to the pathogenesis of atherosclerosis and cardiovascular diseases. However, the mechanism underlying saturated FFA-induced ED remains unclear. This study demonstrated that palmitic acid (PA) induced ED by activating the NADPH oxidase (NOX)/ROS signaling pathway to activate protein phosphatase 4 (PP4) and protein phosphatase 2A (PP2A), thereby reducing endothelial nitric oxide synthase (eNOS) phosphorylation at Ser633 and Ser1177, respectively. Okadaic acid (OA) and fostriecin (FST), which are inhibitors of PP2A, inhibited the PA-induced decreases in eNOS phosphorylation at Ser633 and Ser1177. The antioxidants N-acetylcysteine (NAC) and apocynin (APO) or knockdown of gp91phox or p67phox (NOX subunits) restored PA-mediated downregulation of PP4R2 protein expression and eNOS Ser633 phosphorylation. Knockdown of the PP4 catalytic subunit (PP4c) specifically increased eNOS Ser633 phosphorylation, while silencing the PP2A catalytic subunit (PP2Ac) restored only eNOS Ser1177 phosphorylation. Furthermore, PA dramatically decreased the protein expression of the PP4 regulatory subunit R2 (PP4R2) but not the other regulatory subunits. PP4R2 overexpression increased eNOS Ser633 phosphorylation, nitric oxide (NO) production, cell migration and tube formation but did not change eNOS Ser1177 phosphorylation levels. Coimmunoprecipitation (Co-IP) suggested that PP4R2 and PP4c interacted with the PP4R3α and eNOS proteins. In summary, PA decreases PP4R2 protein expression through the Nox/ROS pathway to activate PP4, which contributes to ED by dephosphorylating eNOS at Ser633. The results of this study suggest that PP4 is a novel therapeutic target for ED and ED-associated vascular diseases.


Assuntos
Óxido Nítrico Sintase Tipo III , Fosfoproteínas Fosfatases , Doenças Vasculares , Humanos , Fosforilação , Óxido Nítrico Sintase Tipo III/metabolismo , Ácido Palmítico/farmacologia , Serina/metabolismo , Espécies Reativas de Oxigênio , Células Cultivadas , Proteína Fosfatase 2/metabolismo , Óxido Nítrico/metabolismo
13.
Mol Ther ; 32(7): 2340-2356, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38715363

RESUMO

Human papillomavirus (HPV) 16 and 18 infections are related to many human cancers. Despite several preventive vaccines for high-risk (hr) HPVs, there is still an urgent need to develop therapeutic HPV vaccines for targeting pre-existing hrHPV infections and lesions. In this study, we developed a lipid nanoparticle (LNP)-formulated mRNA-based HPV therapeutic vaccine (mHTV)-03E2, simultaneously targeting the E2/E6/E7 of both HPV16 and HPV18. mHTV-03E2 dramatically induced antigen-specific cellular immune responses, leading to significant CD8+ T cell infiltration and cytotoxicity in TC-1 tumors derived from primary lung epithelial cells of C57BL/6 mice expressing HPV E6/E7 antigens, mediated significant tumor regression, and prolonged animal survival, in a dose-dependent manner. We further demonstrated significant T cell immunity against HPV16/18 E6/E7 antigens for up to 4 months post-vaccination in immunological and distant tumor rechallenging experiments, suggesting robust memory T cell immunity against relapse. Finally, mHTV-03E2 synergized with immune checkpoint blockade to inhibit tumor growth and extend animal survival, indicating the potential in combination therapy. We conclude that mHTV-03E2 is an excellent candidate therapeutic mRNA vaccine for treating malignancies caused by HPV16 or HPV18 infections.


Assuntos
Proteínas Oncogênicas Virais , Infecções por Papillomavirus , Vacinas contra Papillomavirus , RNA Mensageiro , Animais , Camundongos , Vacinas contra Papillomavirus/imunologia , Humanos , Infecções por Papillomavirus/imunologia , Infecções por Papillomavirus/virologia , Infecções por Papillomavirus/terapia , Infecções por Papillomavirus/prevenção & controle , Feminino , Proteínas Oncogênicas Virais/imunologia , Proteínas Oncogênicas Virais/genética , RNA Mensageiro/genética , RNA Mensageiro/imunologia , Nanopartículas/química , Papillomavirus Humano 16/imunologia , Papillomavirus Humano 16/genética , Camundongos Endogâmicos C57BL , Papillomavirus Humano 18/imunologia , Papillomavirus Humano 18/genética , Proteínas E7 de Papillomavirus/imunologia , Proteínas E7 de Papillomavirus/genética , Vacinas Anticâncer/imunologia , Vacinas Anticâncer/administração & dosagem , Linhagem Celular Tumoral , Modelos Animais de Doenças , Linfócitos T CD8-Positivos/imunologia , Proteínas Repressoras/imunologia , Proteínas Repressoras/genética , Proteínas de Ligação a DNA , Lipossomos
14.
Mol Cell ; 68(5): 993-1005.e9, 2017 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-29107537

RESUMO

Gene expression can be post-transcriptionally regulated via dynamic and reversible RNA modifications. N1-methyladenosine (m1A) is a recently identified mRNA modification; however, little is known about its precise location and biogenesis. Here, we develop a base-resolution m1A profiling method, based on m1A-induced misincorporation during reverse transcription, and report distinct classes of m1A methylome in the human transcriptome. m1A in 5' UTR, particularly those at the mRNA cap, associate with increased translation efficiency. A different, small subset of m1A exhibit a GUUCRA tRNA-like motif, are evenly distributed in the transcriptome, and are dependent on the methyltransferase TRMT6/61A. Additionally, we show that m1A is prevalent in the mitochondrial-encoded transcripts. Manipulation of m1A level via TRMT61B, a mitochondria-localizing m1A methyltransferase, demonstrates that m1A in mitochondrial mRNA interferes with translation. Collectively, our approaches reveal distinct classes of m1A methylome and provide a resource for functional studies of m1A-mediated epitranscriptomic regulation.


Assuntos
Adenosina/análogos & derivados , Núcleo Celular/metabolismo , Mitocôndrias/metabolismo , Processamento Pós-Transcricional do RNA , RNA Mensageiro/metabolismo , RNA de Transferência/metabolismo , Imagem Individual de Molécula/métodos , Regiões 5' não Traduzidas , Adenosina/metabolismo , Células HEK293 , Humanos , Proteínas Mitocondriais/biossíntese , Proteínas Mitocondriais/genética , Proteínas Nucleares/biossíntese , Proteínas Nucleares/genética , Biossíntese de Proteínas , Capuzes de RNA , Interferência de RNA , RNA Mensageiro/genética , RNA de Transferência/genética , Transfecção , tRNA Metiltransferases/genética , tRNA Metiltransferases/metabolismo
15.
Chem Soc Rev ; 53(10): 5014-5053, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38600823

RESUMO

Alumina materials, as one of the cornerstones of the modern chemical industry, possess physical and chemical properties that include excellent mechanical strength and structure stability, which also make them highly suitable as catalyst supports. Alumina-supported Pd-based catalysts with the advantages of exceptional catalytic performance, flexible regulated surface metal/acid sites, and good regeneration ability have been widely used in many traditional chemical industry fields and have also shown great application prospects in emerging fields. This review aims to provide an overview of the recent advances in alumina and its supported Pd-based catalysts. Specifically, the synthesis strategies, morphology transformation mechanisms, and structural properties of alumina with various morphologies are comprehensively summarized and discussed in-depth. Then, the preparation approaches of Pd/Al2O3 catalysts (impregnation, precipitation, and other emerging methods), as well as the metal-support interactions (MSIs), are revisited. Moreover, Some promising applications have been chosen as representative reactions in fine chemicals, environmental purification, and sustainable development fields to highlight the universal functionality of the alumina-supported Pd-based catalysts. The role of the Pd species, alumina support, promoters, and metal-support interactions in the enhancement of catalytic performance are also discussed. Finally, some challenges and upcoming opportunities in the academic and industrial application of the alumina and its supported Pd-based are presented and put forward.

16.
J Am Chem Soc ; 146(35): 24638-24653, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39171830

RESUMO

Identifying biologically active ligands for membrane proteins is an important task in chemical biology. We report an approach to directly identify small molecule agonists against membrane proteins by selecting DNA-encoded libraries (DELs) on live cells. This method connects extracellular ligand binding with intracellular biochemical transformation, thereby biasing the selection toward agonist identification. We have demonstrated the methodology with three membrane proteins: epidermal growth factor receptor (EGFR), thrombopoietin receptor (TPOR), and insulin receptor (INSR). A ∼30 million and a 1.033 billion-compound DEL were selected against these targets, and novel agonists with subnanomolar affinity and low micromolar cellular activities have been discovered. The INSR agonists activated the receptor by possibly binding to an allosteric site, exhibited clear synergistic effects with insulin, and activated the downstream signaling pathways. Notably, the agonists did not activate the insulin-like growth factor 1 receptor (IGF-1R), a highly homologous receptor whose activation may lead to tumor progression. Collectively, this work has developed an approach toward "functional" DEL selections on the cell surface and may provide a widely applicable method for agonist discovery for membrane proteins.


Assuntos
DNA , Receptores ErbB , Receptor de Insulina , Bibliotecas de Moléculas Pequenas , Humanos , Receptor de Insulina/agonistas , Receptor de Insulina/metabolismo , Bibliotecas de Moléculas Pequenas/farmacologia , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/síntese química , DNA/química , DNA/metabolismo , Receptores ErbB/metabolismo , Receptores ErbB/agonistas , Proteínas de Membrana/agonistas , Proteínas de Membrana/metabolismo , Descoberta de Drogas , Células HEK293 , Ligantes , Antígenos CD
17.
Mol Cancer ; 23(1): 123, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38849845

RESUMO

BACKGROUND: Pediatric-type diffuse high-grade glioma (pHGG) is the most frequent malignant brain tumor in children and can be subclassified into multiple entities. Fusion genes activating the MET receptor tyrosine kinase often occur in infant-type hemispheric glioma (IHG) but also in other pHGG and are associated with devastating morbidity and mortality. METHODS: To identify new treatment options, we established and characterized two novel orthotopic mouse models harboring distinct MET fusions. These included an immunocompetent, murine allograft model and patient-derived orthotopic xenografts (PDOX) from a MET-fusion IHG patient who failed conventional therapy and targeted therapy with cabozantinib. With these models, we analyzed the efficacy and pharmacokinetic properties of three MET inhibitors, capmatinib, crizotinib and cabozantinib, alone or combined with radiotherapy. RESULTS: Capmatinib showed superior brain pharmacokinetic properties and greater in vitro and in vivo efficacy than cabozantinib or crizotinib in both models. The PDOX models recapitulated the poor efficacy of cabozantinib experienced by the patient. In contrast, capmatinib extended survival and induced long-term progression-free survival when combined with radiotherapy in two complementary mouse models. Capmatinib treatment increased radiation-induced DNA double-strand breaks and delayed their repair. CONCLUSIONS: We comprehensively investigated the combination of MET inhibition and radiotherapy as a novel treatment option for MET-driven pHGG. Our seminal preclinical data package includes pharmacokinetic characterization, recapitulation of clinical outcomes, coinciding results from multiple complementing in vivo studies, and insights into molecular mechanism underlying increased efficacy. Taken together, we demonstrate the groundbreaking efficacy of capmatinib and radiation as a highly promising concept for future clinical trials.


Assuntos
Neoplasias Encefálicas , Glioma , Proteínas Proto-Oncogênicas c-met , Ensaios Antitumorais Modelo de Xenoenxerto , Animais , Humanos , Glioma/patologia , Glioma/tratamento farmacológico , Glioma/genética , Glioma/terapia , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-met/genética , Proteínas Proto-Oncogênicas c-met/metabolismo , Camundongos , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/radioterapia , Benzamidas/farmacologia , Benzamidas/uso terapêutico , Linhagem Celular Tumoral , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/metabolismo , Feminino , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Piridinas/farmacologia , Piridinas/uso terapêutico , Crizotinibe/farmacologia , Crizotinibe/uso terapêutico , Modelos Animais de Doenças , Criança , Gradação de Tumores , Anilidas/farmacologia , Imidazóis , Triazinas
18.
Apoptosis ; 29(3-4): 289-302, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38095762

RESUMO

Metal ions play an important role in living organisms and are involved in essential physiological activities. However, the overload state of ions can cause excess free radicals, cell damage, and even cell death. Ferroptosis and cuproptosis are specific forms of cell death that are distinct from apoptosis, necroptosis, and other regulated cell death. These unique modalities of cell death, dependent on iron and copper, are regulated by multiple cellular metabolic pathways, including steady-state metal redox treatment mitochondrial activity of lipid, amino acid and glucose metabolism, and various signaling pathways associated with disease. Although the mechanisms of ferroptosis and cuproptosis are not yet fully understood, there is no doubt that ion overload plays a crucial act in these metal-dependent cell deaths. In this review, we discussed the core roles of ion overload in ferroptosis and cuproptosis, the association between metabolism imbalance and ferroptosis and cuproptosis, the extract the diseases caused by ion overload and current treatment modalities.


Assuntos
Ferroptose , Nefropatias , Morte Celular Regulada , Humanos , Ferroptose/genética , Apoptose , Íons
19.
Apoptosis ; 29(1-2): 169-190, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37713112

RESUMO

Cuprotosis, an emerging mode of cell death, has recently caught the attention of researchers worldwide. However, its impact on low-grade glioma (LGG) patients has not been fully explored. To gain a deeper insight into the relationship between cuprotosis and LGG patients' prognosis, we conducted this study in which LGG patients were divided into two clusters based on the expression of 18 cuprotosis-related genes. We found that LGG patients in cluster A had better prognosis than those in cluster B. The two clusters also differed in terms of immune cell infiltration and biological functions. Moreover, we identified differentially expressed genes (DEGs) between the two clusters and developed a cuprotosis-related prognostic signature through the least absolute shrinkage and selection operator (LASSO) analysis in the TCGA training cohort. This signature divided LGG patients into high- and low-risk groups, with the high-risk group having significantly shorter overall survival (OS) time than the low-risk group. Its predictive reliability for prognosis in LGG patients was confirmed by the TCGA internal validation cohort, CGGA325 cohort and CGGA693 cohort. Additionally, a nomogram was used to predict the 1-, 3-, and 5-year OS rates of each patient. The analysis of immune checkpoints and tumor mutation burden (TMB) has revealed that individuals belonging to high-risk groups have a greater chance of benefiting from immunotherapy. Functional experiments confirmed that interfering with the signature gene TNFRSF11B inhibited LGG cell proliferation and migration. Overall, this study shed light on the importance of cuprotosis in LGG patient prognosis. The cuprotosis-related prognostic signature is a reliable predictor for patient outcomes and immunotherapeutic response and can help to develop new therapies for LGG.


Assuntos
Apoptose , Glioma , Humanos , Reprodutibilidade dos Testes , Morte Celular , Glioma/genética , Glioma/terapia , Imunoterapia
20.
Anal Chem ; 96(1): 309-316, 2024 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-38108827

RESUMO

The separation and analysis of circulating tumor cells (CTCs) in liquid biopsy significantly facilitated clinical cancer diagnosis and personalized therapy. However, current methods face challenges in simultaneous efficient capturing, separation, and imaging of CTCs, and most of the devices cannot be reused/regenerated. We present here an innovative glowing octopus-inspired nanomachine (GOIN), capable of capturing, imaging, separating, and controlling the release of cancer cells from whole blood and normal cells. The GOIN comprises an aptamer-decorated magnetic fluorescent covalent organic framework (COF), which exhibits a strong affinity for nucleolin-overexpressed cancer cells through a multivalent binding effect. The captured cancer cells can be directly imaged using the intrinsic stable fluorescence of the COF layer in the GOIN. Employing magnet and NIR laser assistance enables easy separation and mild photothermal release of CTCs from the normal cells and the nanomachine without compromising cell viability. Moreover, the GOIN demonstrates a reusing capability, as the NIR-triggered CTC release is mild and nondestructive, allowing the GOIN to be reused at least three times.


Assuntos
Células Neoplásicas Circulantes , Humanos , Separação Celular/métodos , Células Neoplásicas Circulantes/patologia , Linhagem Celular Tumoral , Diagnóstico por Imagem , Sobrevivência Celular
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