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1.
Cell ; 186(10): 2092-2110.e23, 2023 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-37172563

RESUMO

The third and fourth weeks of gestation in primates are marked by several developmental milestones, including gastrulation and the formation of organ primordia. However, our understanding of this period is limited due to restricted access to in vivo embryos. To address this gap, we developed an embedded 3D culture system that allows for the extended ex utero culture of cynomolgus monkey embryos for up to 25 days post-fertilization. Morphological, histological, and single-cell RNA-sequencing analyses demonstrate that ex utero cultured monkey embryos largely recapitulated key events of in vivo development. With this platform, we were able to delineate lineage trajectories and genetic programs involved in neural induction, lateral plate mesoderm differentiation, yolk sac hematopoiesis, primitive gut, and primordial germ-cell-like cell development in monkeys. Our embedded 3D culture system provides a robust and reproducible platform for growing monkey embryos from blastocysts to early organogenesis and studying primate embryogenesis ex utero.


Assuntos
Embrião de Mamíferos , Desenvolvimento Embrionário , Animais , Macaca fascicularis , Blastocisto , Organogênese , Primatas
2.
Cell ; 152(1-2): 276-89, 2013 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-23273991

RESUMO

MDA5, a viral double-stranded RNA (dsRNA) receptor, shares sequence similarity and signaling pathways with RIG-I yet plays essential functions in antiviral immunity through distinct specificity for viral RNA. Revealing the molecular basis for the functional divergence, we report here the crystal structure of MDA5 bound to dsRNA, which shows how, using the same domain architecture, MDA5 recognizes the internal duplex structure, whereas RIG-I recognizes the terminus of dsRNA. We further show that MDA5 uses direct protein-protein contacts to stack along dsRNA in a head-to-tail arrangement, and that the signaling domain (tandem CARD), which decorates the outside of the core MDA5 filament, also has an intrinsic propensity to oligomerize into an elongated structure that activates the signaling adaptor, MAVS. These data support a model in which MDA5 uses long dsRNA as a signaling platform to cooperatively assemble the core filament, which in turn promotes stochastic assembly of the tandem CARD oligomers for signaling.


Assuntos
RNA Helicases DEAD-box/química , RNA Helicases DEAD-box/metabolismo , RNA de Cadeia Dupla/metabolismo , Sequência de Aminoácidos , Humanos , Helicase IFIH1 Induzida por Interferon , Modelos Moleculares , Dados de Sequência Molecular , Estrutura Terciária de Proteína , RNA de Cadeia Dupla/química , Receptores do Ácido Retinoico/química , Receptores do Ácido Retinoico/metabolismo , Alinhamento de Sequência , Difração de Raios X
3.
PLoS Biol ; 22(7): e3002704, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38954724

RESUMO

The vegetative insecticidal protein Vip3Aa from Bacillus thuringiensis (Bt) has been produced by transgenic crops to counter pest resistance to the widely used crystalline (Cry) insecticidal proteins from Bt. To proactively manage pest resistance, there is an urgent need to better understand the genetic basis of resistance to Vip3Aa, which has been largely unknown. We discovered that retrotransposon-mediated alternative splicing of a midgut-specific chitin synthase gene was associated with 5,560-fold resistance to Vip3Aa in a laboratory-selected strain of the fall armyworm, a globally important crop pest. The same mutation in this gene was also detected in a field population. Knockout of this gene via CRISPR/Cas9 caused high levels of resistance to Vip3Aa in fall armyworm and 2 other lepidopteran pests. The insights provided by these results could help to advance monitoring and management of pest resistance to Vip3Aa.


Assuntos
Bacillus thuringiensis , Proteínas de Bactérias , Quitina Sintase , Resistência a Inseticidas , Retroelementos , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Quitina Sintase/genética , Quitina Sintase/metabolismo , Retroelementos/genética , Bacillus thuringiensis/genética , Resistência a Inseticidas/genética , Sistemas CRISPR-Cas , Processamento Alternativo/genética , Processamento Alternativo/efeitos dos fármacos , Spodoptera/efeitos dos fármacos , Plantas Geneticamente Modificadas , Mariposas/efeitos dos fármacos , Mariposas/genética
4.
Nature ; 600(7887): 81-85, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34853456

RESUMO

Understanding the structure and dynamic process of water at the solid-liquid interface is an extremely important topic in surface science, energy science and catalysis1-3. As model catalysts, atomically flat single-crystal electrodes exhibit well-defined surface and electric field properties, and therefore may be used to elucidate the relationship between structure and electrocatalytic activity at the atomic level4,5. Hence, studying interfacial water behaviour on single-crystal surfaces provides a framework for understanding electrocatalysis6,7. However, interfacial water is notoriously difficult to probe owing to interference from bulk water and the complexity of interfacial environments8. Here, we use electrochemical, in situ Raman spectroscopic and computational techniques to investigate the interfacial water on atomically flat Pd single-crystal surfaces. Direct spectral evidence reveals that interfacial water consists of hydrogen-bonded and hydrated Na+ ion water. At hydrogen evolution reaction (HER) potentials, dynamic changes in the structure of interfacial water were observed from a random distribution to an ordered structure due to bias potential and Na+ ion cooperation. Structurally ordered interfacial water facilitated high-efficiency electron transfer across the interface, resulting in higher HER rates. The electrolytes and electrode surface effects on interfacial water were also probed and found to affect water structure. Therefore, through local cation tuning strategies, we anticipate that these results may be generalized to enable ordered interfacial water to improve electrocatalytic reaction rates.

5.
Proc Natl Acad Sci U S A ; 121(2): e2219352120, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38165927

RESUMO

High levels of mitochondrial reactive oxygen species (mROS) are linked to cancer development, which is tightly controlled by the electron transport chain (ETC). However, the epigenetic mechanisms governing ETC gene transcription to drive mROS production and cancer cell growth remain to be fully characterized. Here, we report that protein demethylase PHF8 is overexpressed in many types of cancers, including colon and lung cancer, and is negatively correlated with ETC gene expression. While it is well known to demethylate histones to activate transcription, PHF8 demethylates transcription factor YY1, functioning as a co-repressor for a large set of nuclear-coded ETC genes to drive mROS production and cancer development. In addition to genetically ablating PHF8, pharmacologically targeting PHF8 with a specific chemical inhibitor, iPHF8, is potent in regulating YY1 methylation, ETC gene transcription, mROS production, and cell growth in colon and lung cancer cells. iPHF8 exhibits potency and safety in suppressing tumor growth in cell-line- and patient-derived xenografts in vivo. Our data uncover a key epigenetic mechanism underlying ETC gene transcriptional regulation, demonstrating that targeting the PHF8/YY1 axis has great potential to treat cancers.


Assuntos
Neoplasias Pulmonares , Fatores de Transcrição , Humanos , Fatores de Transcrição/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Histona Desmetilases/metabolismo , Histonas/metabolismo , Transformação Celular Neoplásica , Neoplasias Pulmonares/genética , Fator de Transcrição YY1/genética , Fator de Transcrição YY1/metabolismo
6.
Brief Bioinform ; 25(5)2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39177264

RESUMO

Recent nanopore sequencing system (R10.4) has enhanced base calling accuracy and is being increasingly utilized for detecting CpG methylation state. However, the robustness and universality of the methylation calling model in officially supplied Dorado remains poorly tested. In this study, we obtained heterogeneous datasets from human and plant sources to carry out comprehensive evaluations, which showed that Dorado performed significantly different across datasets. We therefore developed deep neural networks and implemented several optimizations in training a new model called DeepBAM. DeepBAM achieved superior and more stable performances compared with Dorado, including higher area under the ROC curves (98.47% on average and up to 7.36% improvement) and F1 scores (94.97% on average and up to 16.24% improvement) across the datasets. DeepBAM-based whole genome methylation frequencies have achieved >0.95 correlations with BS-seq on four of five datasets, outperforming Dorado in all instances. It enables unraveling allele-specific methylation patterns, including regions of transposable elements. The enhanced performance of DeepBAM paves the way for broader applications of nanopore sequencing in CpG methylation studies.


Assuntos
Ilhas de CpG , Metilação de DNA , Sequenciamento por Nanoporos , Sequenciamento por Nanoporos/métodos , Humanos , Software , Análise de Sequência de DNA/métodos , Redes Neurais de Computação
7.
Mol Cell ; 70(2): 340-357.e8, 2018 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-29628309

RESUMO

Whereas the actions of enhancers in gene transcriptional regulation are well established, roles of JmjC-domain-containing proteins in mediating enhancer activation remain poorly understood. Here, we report that recruitment of the JmjC-domain-containing protein 6 (JMJD6) to estrogen receptor alpha (ERα)-bound active enhancers is required for RNA polymerase II recruitment and enhancer RNA production on enhancers, resulting in transcriptional pause release of cognate estrogen target genes. JMJD6 is found to interact with MED12 in the mediator complex to regulate its recruitment. Unexpectedly, JMJD6 is necessary for MED12 to interact with CARM1, which methylates MED12 at multiple arginine sites and regulates its chromatin binding. Consistent with its role in transcriptional activation, JMJD6 is required for estrogen/ERα-induced breast cancer cell growth and tumorigenesis. Our data have uncovered a critical regulator of estrogen/ERα-induced enhancer coding gene activation and breast cancer cell potency, providing a potential therapeutic target of ER-positive breast cancers.


Assuntos
Neoplasias da Mama/enzimologia , Proliferação de Células , Receptor alfa de Estrogênio/metabolismo , Histona Desmetilases com o Domínio Jumonji/metabolismo , Complexo Mediador/metabolismo , Proteína-Arginina N-Metiltransferases/metabolismo , Ativação Transcricional , Animais , Sítios de Ligação , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Proliferação de Células/efeitos dos fármacos , Estradiol/farmacologia , Receptor alfa de Estrogênio/agonistas , Receptor alfa de Estrogênio/genética , Feminino , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Humanos , Histona Desmetilases com o Domínio Jumonji/genética , Células MCF-7 , Complexo Mediador/genética , Camundongos Endogâmicos BALB C , Camundongos Nus , Ligação Proteica , Transporte Proteico , Proteína-Arginina N-Metiltransferases/genética , Transdução de Sinais , Ativação Transcricional/efeitos dos fármacos
8.
Nucleic Acids Res ; 52(12): 6811-6829, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38676947

RESUMO

Protein arginine methyltransferase CARM1 has been shown to methylate a large number of non-histone proteins, and play important roles in gene transcriptional activation, cell cycle progress, and tumorigenesis. However, the critical substrates through which CARM1 exerts its functions remain to be fully characterized. Here, we reported that CARM1 directly interacts with the GATAD2A/2B subunit in the nucleosome remodeling and deacetylase (NuRD) complex, expanding the activities of NuRD to include protein arginine methylation. CARM1 and NuRD bind and activate a large cohort of genes with implications in cell cycle control to facilitate the G1 to S phase transition. This gene activation process requires CARM1 to hypermethylate GATAD2A/2B at a cluster of arginines, which is critical for the recruitment of the NuRD complex. The clinical significance of this gene activation mechanism is underscored by the high expression of CARM1 and NuRD in breast cancers, and the fact that knockdown CARM1 and NuRD inhibits cancer cell growth in vitro and tumorigenesis in vivo. Targeting CARM1-mediated GATAD2A/2B methylation with CARM1 specific inhibitors potently inhibit breast cancer cell growth in vitro and tumorigenesis in vivo. These findings reveal a gene activation program that requires arginine methylation established by CARM1 on a key chromatin remodeler, and targeting such methylation might represent a promising therapeutic avenue in the clinic.


Assuntos
Neoplasias da Mama , Montagem e Desmontagem da Cromatina , Regulação Neoplásica da Expressão Gênica , Complexo Mi-2 de Remodelação de Nucleossomo e Desacetilase , Proteína-Arginina N-Metiltransferases , Complexo Mi-2 de Remodelação de Nucleossomo e Desacetilase/metabolismo , Complexo Mi-2 de Remodelação de Nucleossomo e Desacetilase/genética , Proteína-Arginina N-Metiltransferases/genética , Proteína-Arginina N-Metiltransferases/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Humanos , Feminino , Animais , Linhagem Celular Tumoral , Ciclo Celular/genética , Camundongos , Metilação , Arginina/metabolismo , Carcinogênese/genética , Ativação Transcricional
9.
Plant J ; 117(1): 107-120, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37753665

RESUMO

Black pepper (Piper nigrum L.), the world renown as the King of Spices, is not only a flavorsome spice but also a traditional herb. Piperine, a species-specific piper amide, is responsible for the major bioactivity and pungent flavor of black pepper. However, several key steps for the biosynthesis of piperoyl-CoA (acyl-donor) and piperidine (acyl-acceptor), two direct precursors for piperine, remain unknown. In this study, we used guilt-by-association analysis of the combined metabolome and transcriptome, to identify two feruloyldiketide-CoA synthases responsible for the production of the C5 side chain scaffold feruloyldiketide-CoA intermediate, which is considered the first and important step to branch metabolic fluxes from phenylpropanoid pathway to piperine biosynthesis. In addition, we also identified the first two key enzymes for piperidine biosynthesis derived from lysine in P. nigrum, namely a lysine decarboxylase and a copper amine oxidase. These enzymes catalyze the production of cadaverine and 1-piperideine, the precursors of piperidine. In vivo and in vitro experiments verified the catalytic capability of them. In conclusion, our findings revealed enigmatic key steps of piperine biosynthetic pathway and thus provide a powerful reference for dissecting the biosynthetic logic of other piper amides.


Assuntos
Piper nigrum , Piper nigrum/genética , Alcamidas Poli-Insaturadas , Piperidinas , Perfilação da Expressão Gênica , Metaboloma
10.
Brief Bioinform ; 25(1)2023 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-38040492

RESUMO

Accurate prediction of TCR-pMHC binding is important for the development of cancer immunotherapies, especially TCR-based agents. Existing algorithms often experience diminished performance when dealing with unseen epitopes, primarily due to the complexity in TCR-pMHC recognition patterns and the scarcity of available data for training. We have developed a novel deep learning model, 'TCR Antigen Binding Recognition' based on BERT, named as TABR-BERT. Leveraging BERT's potent representation learning capabilities, TABR-BERT effectively captures essential information regarding TCR-pMHC interactions from TCR sequences, antigen epitope sequences and epitope-MHC binding. By transferring this knowledge to predict TCR-pMHC recognition, TABR-BERT demonstrated better results in benchmark tests than existing methods, particularly for unseen epitopes.


Assuntos
Algoritmos , Receptores de Antígenos de Linfócitos T , Receptores de Antígenos de Linfócitos T/genética , Ligação Proteica , Epitopos/metabolismo , Aprendizado de Máquina
11.
J Am Chem Soc ; 146(18): 12538-12546, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38656110

RESUMO

There is growing acknowledgment that the properties of the electrochemical interfaces play an increasingly pivotal role in improving the performance of the hydrogen evolution reaction (HER). Here, we present, for the first time, direct dynamic spectral evidence illustrating the impact of the interaction between interfacial water molecules and adsorbed hydroxyl species (OHad) on the HER properties of Ni(OH)2 using Au/core-Ni(OH)2/shell nanoparticle-enhanced Raman spectroscopy. Notably, our findings highlight that the interaction between OHad and interfacial water molecules promotes the formation of weakly hydrogen-bonded water, fostering an environment conducive to improving the HER performance. Furthermore, the participation of OHad in the reaction is substantiated by the observed deprotonation step of Au@2 nm Ni(OH)2 during the HER process. This phenomenon is corroborated by the phase transition of Ni(OH)2 to NiO, as verified through Raman and X-ray photoelectron spectroscopy. The significant redshift in the OH-stretching frequency of water molecules during the phase transition confirms that surface OHad disrupts the hydrogen-bond network of interfacial water molecules. Through manipulation of the shell thickness of Au@Ni(OH)2, we additionally validate the interaction between OHad and interfacial water molecules. In summary, our insights emphasize the potential of electrochemical interfacial engineering as a potent approach to enhance electrocatalytic performance.

12.
J Am Chem Soc ; 146(18): 12723-12733, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38654452

RESUMO

Enfumafungin-type antibiotics, represented by enfumafungin and fuscoatroside, belong to a distinct group of triterpenoids derived from fungi. These compounds exhibit significant antifungal properties with ibrexafungerp, a semisynthetic derivative of enfumafungin, recently gaining FDA's approval as the first oral antifungal drug for treating invasive vulvar candidiasis. Enfumafungin-type antibiotics possess a cleaved E-ring with an oxidized carboxyl group and a reduced methyl group at the break site, suggesting unprecedented C-C bond cleavage chemistry involved in their biosynthesis. Here, we show that a 4-gene (fsoA, fsoD, fsoE, fsoF) biosynthetic gene cluster is sufficient to yield fuscoatroside by heterologous expression in Aspergillus oryzae. Notably, FsoA is an unheard-of terpene cyclase-glycosyltransferase fusion enzyme, affording a triterpene glycoside product that relies on enzymatic fusion. FsoE is a P450 enzyme that catalyzes successive oxidation reactions at C19 to facilitate a C-C bond cleavage, producing an oxidized carboxyl group and a reduced methyl group that have never been observed in known P450 enzymes. Our study thus sets the important foundation for the manufacture of enfumafungin-type antibiotics using biosynthetic approaches.


Assuntos
Antifúngicos , Antifúngicos/química , Antifúngicos/farmacologia , Antifúngicos/metabolismo , Aspergillus oryzae/enzimologia , Aspergillus oryzae/metabolismo , Família Multigênica , Triterpenos/química , Triterpenos/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo
13.
Cancer Immunol Immunother ; 73(11): 232, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39264449

RESUMO

Tumor-infiltrating lymphocyte (TIL) therapy represents a groundbreaking advancement in the solid cancer treatment, offering new hope to patients and their families with high response rates and long overall survival. TIL therapy involves extracting immune cells from a patient's tumor tissue, expanding them ex vivo, and infusing them back into the patient to target and eliminate cancer cells. This revolutionary approach harnesses the power of the immune system to combat cancers, ushering in a new era of T cell-based therapies along with CAR-T and TCR-therapies. In this comprehensive review, we aim to elucidate the remarkable potential of TIL therapy by delving into recent advancements in basic and clinical researches. We highlight on the evolving landscape of TIL therapy as a prominent immunotherapeutic strategy, its multifaceted applications, and the promising outcomes. Additionally, we explore the future horizons of TIL therapy, next-generation TILs, and combination therapy, to overcome the limitations and improve clinical efficacy of TIL therapy.


Assuntos
Imunoterapia Adotiva , Linfócitos do Interstício Tumoral , Neoplasias , Humanos , Linfócitos do Interstício Tumoral/imunologia , Neoplasias/terapia , Neoplasias/imunologia , Imunoterapia Adotiva/métodos , Animais , Terapia Combinada/métodos
14.
Small ; 20(28): e2311393, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38287737

RESUMO

Electrolyte plays a crucial role in ensuring stable operation of lithium metal batteries (LMBs). Localized high-concentration electrolytes (LHCEs) have the potential to form a robust solid-electrolyte interphase (SEI) and mitigate Li dendrite growth, making them a highly promising electrolyte option. However, the principles governing the selection of diluents, a crucial component in LHCE, have not been clearly determined, hampering the advancement of such a type of electrolyte systems. Herein, the diluents from the perspective of molecular polarity are rationally designed and developed. A moderately fluorinated solvent, 1-(1,1,2,2-tetrafluoroethoxy)propane (TNE), is employed as a diluent to create a novel LHCE. The unique molecular structure of TNE enhances the intrinsic dipole moment, thereby altering solvent interactions and the coordination environment of Li-ions in LHCE. The achieved solvation structure not only enhances the bulk properties of LHCE, but also facilitates the formation of more stable anion-derived SEIs featured with a higher proportion of inorganic species. Consequently, the corresponding full cells of both Li||LiFePO4 and Li||LiNi0.8Co0.1Mn0.1O2 cells utilizing Li thin-film anodes exhibit extended long-term stability with significantly improved average Coulombic efficiency. This work offers new insights into the functions of diluents in LHCEs and provides direction for further optimizing the LHCEs for LMBs.

15.
PLoS Pathog ; 18(8): e1010692, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35939498

RESUMO

Herpes simplex virus 1 (HSV-1)-induced encephalitis is the most common cause of sporadic, fatal encephalitis in humans. HSV-1 has at least 10 different envelope glycoproteins, which can promote virus infection. The ligands for most of the envelope glycoproteins and the significance of these ligands in virus-induced encephalitis remain elusive. Here, we show that glycoprotein E (gE) binds to the cellular protein, annexin A1 (Anx-A1) to enhance infection. Anx-A1 can be detected on the surface of cells permissive for HSV-1 before infection and on virions. Suppression of Anx-A1 or its receptor, formyl peptide receptor 2 (FPR2), on the cell surface and gE or Anx-A1 on HSV-1 envelopes reduced virus binding to cells. Importantly, Anx-A1 knockout, Anx-A1 knockdown, or treatments with the FPR2 antagonist reduced the mortality and tissue viral loads of infected mice. Our results show that Anx-A1 is a novel enhancing factor of HSV-1 infection. Anx-A1-deficient mice displayed no evident physiology and behavior changes. Hence, targeting Anx-A1 and FPR2 could be a promising prophylaxis or adjuvant therapy to decrease HSV-1 lethality.


Assuntos
Anexina A1 , Encefalite , Herpes Simples , Herpesvirus Humano 1 , Animais , Anexina A1/genética , Anexina A1/metabolismo , Glicoproteínas/metabolismo , Herpesvirus Humano 1/metabolismo , Humanos , Camundongos
16.
BMC Microbiol ; 24(1): 151, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38702601

RESUMO

BACKGROUND: Fluoride-resistant Streptococcus mutans (S. mutans) strains have developed due to the wide use of fluoride in dental caries prevention. However, the metabolomics of fluoride-resistant S. mutans remains unclear. OBJECTIVE: This study aimed to identify metabolites that discriminate fluoride-resistant from wild-type S. mutans. MATERIALS AND METHODS: Cell supernatants from fluoride-resistant and wild-type S. mutans were collected and analyzed by liquid chromatography-mass spectrometry. Principal components analysis and partial least-squares discriminant analysis were performed for the statistical analysis by variable influence on projection (VIP > 2.0) and p value (Mann-Whitney test, p < 0.05). Metabolites were assessed qualitatively using the Human Metabolome Database version 2.0 ( http://www.hmdb.ca ), or Kyoto Encyclopedia of Genes and Genomes ( http://www.kegg.jp ), and Metaboanalyst 6.0 ( https://www.metaboanalyst.ca ). RESULTS: Fourteen metabolites differed significantly between fluoride-resistant and wild-type strains in the early log phase. Among these metabolites, 5 were identified. There were 32 differential metabolites between the two strains in the stationary phase, 13 of which were identified. The pyrimidine metabolism for S. mutans FR was matched with the metabolic pathway. CONCLUSIONS: The fructose-1,6-bisphosphate concentration increased in fluoride-resistant strains under acidic conditions, suggesting enhanced acidogenicity and acid tolerance. This metabolite may be a promising target for elucidating the cariogenic and fluoride resistant mechanisms of S. mutans.


Assuntos
Farmacorresistência Bacteriana , Fluoretos , Frutosedifosfatos , Metabolômica , Streptococcus mutans , Streptococcus mutans/efeitos dos fármacos , Streptococcus mutans/genética , Streptococcus mutans/metabolismo , Metabolômica/métodos , Fluoretos/metabolismo , Fluoretos/farmacologia , Frutosedifosfatos/metabolismo , Humanos , Metaboloma/efeitos dos fármacos , Cárie Dentária/microbiologia , Cromatografia Líquida
17.
Plant Cell Environ ; 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39262278

RESUMO

Plants have developed various resistance mechanisms against herbivorous insects through prolonged coevolution. Plant defence responses can be triggered by specific compounds present in insect saliva. Apyrase, a known enzyme that catalyzes the hydrolysis of adenosine triphosphate (ATP) and adenosine diphosphate (ADP) into adenosine monophosphate (AMP) and inorganic phosphorus, has recently been identified in some herbivorous insects. However, whether insect salivary apyrase induces or inhibits plant responses remains poorly understood. In this study, we identified an apyrase-like protein in the salivary proteome of the fall armyworm, Spodoptera frugiperda, named Sfapyrase. Sfapyrase was primarily expressed in the salivary gland and secreted into plants during insect feeding. Transient expression of Sfapyrase in tobacco and maize enhanced plant resistance and resulted in decreased insect feeding. Knockdown of Sfapyrase through RNA interference led to increased growth and feeding of S. frugiperda. Furthermore, we showed that Sfapyrase activates the jasmonic acid signalling pathway and promotes the synthesis of secondary metabolites, especially benzoxazinoids, thereby enhancing resistance to S. frugiperda. In summary, our findings demonstrated that Sfapyrase acts as a salivary elicitor, inducing maize jasmonic acid defence responses and the production of insect-resistant benzoxazinoids. This study provides valuable insights into plant-insect interactions and offers potential targets for developing innovative insect pest management strategies.

18.
Exp Dermatol ; 33(1): e14915, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37638770

RESUMO

Fibrinogen is a protein that reflects systemic inflammation and regulates the immune response to disease. However, there is a scarcity of data on fibrinogen in recurrent aphthous stomatitis (RAS). We aimed to test the hypothesis that fibrinogen is involved in the aetiology of RAS. Between November 2016 and November 2018, we included 109 minor RAS patients and 29 age- and sex-matched controls in a single-center, observational study. Their clinical history and ulcer manifestations led to the diagnosis of minor RAS. The ulcer severity score (USS) was used to assess disease severity, and fibrinogen was also collected. We conducted three analyses: Analysis 1 (comparison of fibrinogen levels between patients and controls), Analysis 2 (comparison of fibrinogen levels between high and low USS patients) and Analysis 3 (comparison of fibrinogen levels between before and after anti-inflammatory treatment in patients). The fibrinogen levels in the 109 minor RAS patients were statistically higher than in the 29 controls (mean [SD], 2.6 [0.5] vs. 2.3 [0.3]; Student's t-test, p < 0.001). However, there were no significant differences in fibrinogen levels among the 43 patients with high USS and the 39 patients with low USS (mean [SD], 2.7 [0.5] vs. 2.6 [0.4]; Student's t-test, p = 0.278). Furthermore, fibrinogen levels were significantly higher before anti-inflammatory treatment in comparison to those after anti-inflammatory treatment in the 35 paired patients (mean [SD], 2.6 [0.4] vs. 2.5 [0.4]; Student's t-test, p = 0.026). Interestingly, fibrinogen levels were significantly higher in the 35 paired patients after anti-inflammatory treatment compared to the 29 control subjects (mean [SD], 2.5 [0.4] vs. 2.3 [0.3]; Student's t-test, p = 0.026]. Fibrinogen may play a role in the aetiology of RAS and may be a drug target for RAS treatment. Clinicians should be alert that high serum fibrinogen levels might be associated with the risk of RAS.


Assuntos
Estomatite Aftosa , Humanos , Estomatite Aftosa/complicações , Estomatite Aftosa/tratamento farmacológico , Úlcera/complicações , Úlcera/tratamento farmacológico , Anti-Inflamatórios/uso terapêutico , Fibrinogênio , China
19.
Mol Psychiatry ; 28(2): 919-930, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36280756

RESUMO

Chronic ethanol exposure (CEE), which can lead to neuroinflammation, is an increasing risk factor for depression disorder, but the underlying mechanism is not clear. Recent observations have revealed the associations among psychiatric disorders, ethanol exposure and alterations of the gut microbiota. Here, we found that CEE induced depressive-like behavior, which could be alleviated by probiotics and transferred from donor to recipient mice by fecal microbiota transplantation (FMT). Neuroinflammation and the activation of the NLRP3 inflammasome were also observed in recipient mice. The downregulation of NLRP3 in the hippocampus mitigated CEE-induced depressive-like behavior and neuroinflammation but had no significant effect on FMT recipient mice. Moreover, elevated serum inflammatory factors in recipient mice showed a significant mediation effect between the gut microbiota and depressive-like behavior. Together, our study findings indicate that the gut microbiota contributes to both hippocampal NLRP3-mediated neuroinflammation and depressive-like behavior induced by CEE, which may open avenues for potential interventions against CEE-associated psychiatric disorders.


Assuntos
Microbioma Gastrointestinal , Camundongos , Animais , Microbioma Gastrointestinal/fisiologia , Proteína 3 que Contém Domínio de Pirina da Família NLR , Doenças Neuroinflamatórias , Etanol/farmacologia , Depressão/psicologia , Inflamassomos/metabolismo , Hipocampo/metabolismo
20.
J Org Chem ; 89(12): 8815-8827, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38835152

RESUMO

S-Glycosides are more resistant to enzymatic and chemical hydrolysis and exhibit higher metabolic stability than common O-glycosides, demonstrating their widespread application in biological research and drug development. In particular, ß-S-glycosides are used as antirheumatic, anticancer, and antidiabetic drugs in clinical practice. However, the stereoselective synthesis of ß-S-glycosides is still highly challenging. Herein, we report an effective ß-S-glycosylation using 3-O-trichloroacetimidoyl glycal and thiols under mild conditions. The C3-imidate is designed to guide Pd to form a complex with glucal from the upper face, followed by Pd-S (thiols) coordination to realize ß-stereoselectivity. This method demonstrates excellent compatibility with a broad scope of various thiol acceptors and glycal donors with yields up to 87% and a ß/α ratio of up to 20:1. The present ß-S-glycosylation strategy is used for late-stage functionalization of drugs/natural products such as estrone, zingerone, and thymol. Overall, this novel and simple operation approach provides a general and practical strategy for the construction of ß-thioglycosides, which holds high potential in drug discovery and development.


Assuntos
Glicosídeos , Paládio , Glicosídeos/química , Glicosídeos/síntese química , Paládio/química , Estereoisomerismo , Catálise , Glicosilação , Estrutura Molecular
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