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1.
Cell ; 184(13): 3394-3409.e20, 2021 06 24.
Artículo en Inglés | MEDLINE | ID: mdl-34077752

RESUMEN

The human fetal immune system begins to develop early during gestation; however, factors responsible for fetal immune-priming remain elusive. We explored potential exposure to microbial agents in utero and their contribution toward activation of memory T cells in fetal tissues. We profiled microbes across fetal organs using 16S rRNA gene sequencing and detected low but consistent microbial signal in fetal gut, skin, placenta, and lungs in the 2nd trimester of gestation. We identified several live bacterial strains including Staphylococcus and Lactobacillus in fetal tissues, which induced in vitro activation of memory T cells in fetal mesenteric lymph node, supporting the role of microbial exposure in fetal immune-priming. Finally, using SEM and RNA-ISH, we visualized discrete localization of bacteria-like structures and eubacterial-RNA within 14th weeks fetal gut lumen. These findings indicate selective presence of live microbes in fetal organs during the 2nd trimester of gestation and have broader implications toward the establishment of immune competency and priming before birth.


Asunto(s)
Bacterias/metabolismo , Desarrollo Embrionario , Feto/citología , Feto/microbiología , Leucocitos/citología , Adulto , Bacterias/genética , Bacterias/ultraestructura , Proliferación Celular , Células Dendríticas/metabolismo , Femenino , Feto/ultraestructura , Tracto Gastrointestinal/embriología , Tracto Gastrointestinal/ultraestructura , Humanos , Memoria Inmunológica , Activación de Linfocitos/inmunología , Viabilidad Microbiana , Embarazo , Segundo Trimestre del Embarazo , ARN Bacteriano/genética , ARN Ribosómico 16S/genética , Reproducibilidad de los Resultados , Linfocitos T/citología
2.
Nat Immunol ; 22(1): 41-52, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33139915

RESUMEN

Personalized cancer vaccines are a promising approach for inducing T cell immunity to tumor neoantigens. Using a self-assembling nanoparticle vaccine that links neoantigen peptides to a Toll-like receptor 7/8 agonist (SNP-7/8a), we show how the route and dose alter the magnitude and quality of neoantigen-specific CD8+ T cells. Intravenous vaccination (SNP-IV) induced a higher proportion of TCF1+PD-1+CD8+ T cells as compared to subcutaneous immunization (SNP-SC). Single-cell RNA sequencing showed that SNP-IV induced stem-like genes (Tcf7, Slamf6, Xcl1) whereas SNP-SC enriched for effector genes (Gzmb, Klrg1, Cx3cr1). Stem-like cells generated by SNP-IV proliferated and differentiated into effector cells upon checkpoint blockade, leading to superior antitumor response as compared to SNP-SC in a therapeutic model. The duration of antigen presentation by dendritic cells controlled the magnitude and quality of CD8+ T cells. These data demonstrate how to optimize antitumor immunity by modulating vaccine parameters for specific generation of effector or stem-like CD8+ T cells.


Asunto(s)
Antígenos de Neoplasias/inmunología , Linfocitos T CD8-positivos/inmunología , Vacunas contra el Cáncer/administración & dosificación , Factor Nuclear 1-alfa del Hepatocito/análisis , Nanopartículas , Animales , Presentación de Antígeno , Vacunas contra el Cáncer/inmunología , Células Dendríticas/inmunología , Femenino , Inmunidad Innata , Ratones , Ratones Endogámicos C57BL , Vacunación
3.
Immunity ; 55(8): 1448-1465.e6, 2022 08 09.
Artículo en Inglés | MEDLINE | ID: mdl-35931085

RESUMEN

Brain macrophage populations include parenchymal microglia, border-associated macrophages, and recruited monocyte-derived cells; together, they control brain development and homeostasis but are also implicated in aging pathogenesis and neurodegeneration. The phenotypes, localization, and functions of each population in different contexts have yet to be resolved. We generated a murine brain myeloid scRNA-seq integration to systematically delineate brain macrophage populations. We show that the previously identified disease-associated microglia (DAM) population detected in murine Alzheimer's disease models actually comprises two ontogenetically and functionally distinct cell lineages: embryonically derived triggering receptor expressed on myeloid cells 2 (TREM2)-dependent DAM expressing a neuroprotective signature and monocyte-derived TREM2-expressing disease inflammatory macrophages (DIMs) accumulating in the brain during aging. These two distinct populations appear to also be conserved in the human brain. Herein, we generate an ontogeny-resolved model of brain myeloid cell heterogeneity in development, homeostasis, and disease and identify cellular targets for the treatment of neurodegeneration.


Asunto(s)
Enfermedad de Alzheimer , Microglía , Envejecimiento , Enfermedad de Alzheimer/genética , Animales , Encéfalo/patología , Humanos , Macrófagos/patología , Glicoproteínas de Membrana , Ratones , Microglía/patología , Receptores Inmunológicos
4.
Immunity ; 54(8): 1883-1900.e5, 2021 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-34331874

RESUMEN

Mononuclear phagocytes (MNPs) encompass dendritic cells, monocytes, and macrophages (MoMac), which exhibit antimicrobial, homeostatic, and immunoregulatory functions. We integrated 178,651 MNPs from 13 tissues across 41 datasets to generate a MNP single-cell RNA compendium (MNP-VERSE), a publicly available tool to map MNPs and define conserved gene signatures of MNP populations. Next, we generated a MoMac-focused compendium that revealed an array of specialized cell subsets widely distributed across multiple tissues. Specific pathological forms were expanded in cancer and inflammation. All neoplastic tissues contained conserved tumor-associated macrophage populations. In particular, we focused on IL4I1+CD274(PD-L1)+IDO1+ macrophages, which accumulated in the tumor periphery in a T cell-dependent manner via interferon-γ (IFN-γ) and CD40/CD40L-induced maturation from IFN-primed monocytes. IL4I1_Macs exhibited immunosuppressive characteristics through tryptophan degradation and promoted the entry of regulatory T cell into tumors. This integrated analysis provides a robust online-available platform for uniform annotation and dissection of specific macrophage functions in healthy and pathological states.


Asunto(s)
Células Dendríticas/inmunología , Expresión Génica/inmunología , Monocitos/inmunología , Transcriptoma/genética , Macrófagos Asociados a Tumores/inmunología , Artritis Reumatoide/inmunología , COVID-19/inmunología , Expresión Génica/genética , Perfilación de la Expresión Génica , Humanos , Interferón gamma/inmunología , L-Aminoácido Oxidasa/metabolismo , Cirrosis Hepática/inmunología , Macrófagos/inmunología , Neoplasias/inmunología , ARN Citoplasmático Pequeño/genética , Análisis de la Célula Individual , Linfocitos T Reguladores/inmunología , Transcriptoma/inmunología
5.
Immunity ; 54(9): 2101-2116.e6, 2021 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-34469775

RESUMEN

Tissue macrophages are immune cells whose phenotypes and functions are dictated by origin and niches. However, tissues are complex environments, and macrophage heterogeneity within the same organ has been overlooked so far. Here, we used high-dimensional approaches to characterize macrophage populations in the murine liver. We identified two distinct populations among embryonically derived Kupffer cells (KCs) sharing a core signature while differentially expressing numerous genes and proteins: a major CD206loESAM- population (KC1) and a minor CD206hiESAM+ population (KC2). KC2 expressed genes involved in metabolic processes, including fatty acid metabolism both in steady-state and in diet-induced obesity and hepatic steatosis. Functional characterization by depletion of KC2 or targeted silencing of the fatty acid transporter Cd36 highlighted a crucial contribution of KC2 in the liver oxidative stress associated with obesity. In summary, our study reveals that KCs are more heterogeneous than anticipated, notably describing a subpopulation wired with metabolic functions.


Asunto(s)
Antígenos CD36/metabolismo , Macrófagos del Hígado/metabolismo , Hígado/metabolismo , Obesidad/metabolismo , Estrés Oxidativo/fisiología , Animales , Ratones
6.
Nature ; 623(7986): 397-405, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37914940

RESUMEN

Microglia are specialized brain-resident macrophages that arise from primitive macrophages colonizing the embryonic brain1. Microglia contribute to multiple aspects of brain development, but their precise roles in the early human brain remain poorly understood owing to limited access to relevant tissues2-6. The generation of brain organoids from human induced pluripotent stem cells recapitulates some key features of human embryonic brain development7-10. However, current approaches do not incorporate microglia or address their role in organoid maturation11-21. Here we generated microglia-sufficient brain organoids by coculturing brain organoids with primitive-like macrophages generated from the same human induced pluripotent stem cells (iMac)22. In organoid cocultures, iMac differentiated into cells with microglia-like phenotypes and functions (iMicro) and modulated neuronal progenitor cell (NPC) differentiation, limiting NPC proliferation and promoting axonogenesis. Mechanistically, iMicro contained high levels of PLIN2+ lipid droplets that exported cholesterol and its esters, which were taken up by NPCs in the organoids. We also detected PLIN2+ lipid droplet-loaded microglia in mouse and human embryonic brains. Overall, our approach substantially advances current human brain organoid approaches by incorporating microglial cells, as illustrated by the discovery of a key pathway of lipid-mediated crosstalk between microglia and NPCs that leads to improved neurogenesis.


Asunto(s)
Encéfalo , Colesterol , Células Madre Pluripotentes Inducidas , Microglía , Células-Madre Neurales , Neurogénesis , Organoides , Animales , Humanos , Ratones , Encéfalo/citología , Encéfalo/metabolismo , Diferenciación Celular , Células Madre Pluripotentes Inducidas/citología , Microglía/citología , Microglía/metabolismo , Organoides/citología , Organoides/metabolismo , Colesterol/metabolismo , Células-Madre Neurales/citología , Células-Madre Neurales/metabolismo , Axones , Proliferación Celular , Ésteres/metabolismo , Gotas Lipídicas/metabolismo
7.
Immunity ; 51(3): 573-589.e8, 2019 09 17.
Artículo en Inglés | MEDLINE | ID: mdl-31474513

RESUMEN

Human mononuclear phagocytes comprise phenotypically and functionally overlapping subsets of dendritic cells (DCs) and monocytes, but the extent of their heterogeneity and distinct markers for subset identification remains elusive. By integrating high-dimensional single-cell protein and RNA expression data, we identified distinct markers to delineate monocytes from conventional DC2 (cDC2s). Using CD88 and CD89 for monocytes and HLA-DQ and FcεRIα for cDC2s allowed for their specific identification in blood and tissues. We also showed that cDC2s could be subdivided into phenotypically and functionally distinct subsets based on CD5, CD163, and CD14 expression, including a distinct subset of circulating inflammatory CD5-CD163+CD14+ cells related to previously defined DC3s. These inflammatory DC3s were expanded in systemic lupus erythematosus patients and correlated with disease activity. These findings further unravel the heterogeneity of DC subpopulations in health and disease and may pave the way for the identification of specific DC subset-targeting therapies.


Asunto(s)
Biomarcadores/sangre , Células Dendríticas/inmunología , Inflamación/sangre , Inflamación/inmunología , Leucocitos Mononucleares/inmunología , Fagocitos/inmunología , Antígenos CD/sangre , Antígenos CD/inmunología , Células Cultivadas , Citometría de Flujo/métodos , Humanos , Lupus Eritematoso Sistémico/sangre , Lupus Eritematoso Sistémico/inmunología , Monocitos/inmunología , Fenotipo , Análisis de la Célula Individual
8.
Proc Natl Acad Sci U S A ; 121(21): e2319060121, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38753516

RESUMEN

Multicellular organisms are composed of many tissue types that have distinct morphologies and functions, which are largely driven by specialized proteomes and interactomes. To define the proteome and interactome of a specific type of tissue in an intact animal, we developed a localized proteomics approach called Methionine Analog-based Cell-Specific Proteomics and Interactomics (MACSPI). This method uses the tissue-specific expression of an engineered methionyl-tRNA synthetase to label proteins with a bifunctional amino acid 2-amino-5-diazirinylnonynoic acid in selected cells. We applied MACSPI in Caenorhabditis elegans, a model multicellular organism, to selectively label, capture, and profile the proteomes of the body wall muscle and the nervous system, which led to the identification of tissue-specific proteins. Using the photo-cross-linker, we successfully profiled HSP90 interactors in muscles and neurons and identified tissue-specific interactors and stress-related interactors. Our study demonstrates that MACSPI can be used to profile tissue-specific proteomes and interactomes in intact multicellular organisms.


Asunto(s)
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Proteoma , Proteómica , Animales , Caenorhabditis elegans/metabolismo , Proteómica/métodos , Proteínas de Caenorhabditis elegans/metabolismo , Proteoma/metabolismo , Metionina-ARNt Ligasa/metabolismo , Metionina-ARNt Ligasa/genética , Proteínas HSP90 de Choque Térmico/metabolismo , Especificidad de Órganos , Músculos/metabolismo , Neuronas/metabolismo
9.
Brief Bioinform ; 25(5)2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39082651

RESUMEN

Constructing accurate gene regulatory network s (GRNs), which reflect the dynamic governing process between genes, is critical to understanding the diverse cellular process and unveiling the complexities in biological systems. With the development of computer sciences, computational-based approaches have been applied to the GRNs inference task. However, current methodologies face challenges in effectively utilizing existing topological information and prior knowledge of gene regulatory relationships, hindering the comprehensive understanding and accurate reconstruction of GRNs. In response, we propose a novel graph neural network (GNN)-based Multi-Task Learning framework for GRN reconstruction, namely MTLGRN. Specifically, we first encode the gene promoter sequences and the gene biological features and concatenate the corresponding feature representations. Then, we construct a multi-task learning framework including GRN reconstruction, Gene knockout predict, and Gene expression matrix reconstruction. With joint training, MTLGRN can optimize the gene latent representations by integrating gene knockout information, promoter characteristics, and other biological attributes. Extensive experimental results demonstrate superior performance compared with state-of-the-art baselines on the GRN reconstruction task, efficiently leveraging biological knowledge and comprehensively understanding the gene regulatory relationships. MTLGRN also pioneered attempts to simulate gene knockouts on bulk data by incorporating gene knockout information.


Asunto(s)
Biología Computacional , Redes Reguladoras de Genes , Biología Computacional/métodos , Técnicas de Inactivación de Genes , Redes Neurales de la Computación , Humanos , Regiones Promotoras Genéticas , Algoritmos
10.
Plant J ; 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39292875

RESUMEN

"Jiaobai" is a symbiont of Zizania latifolia and Ustilago esculenta, producing fleshy galls as a popular vegetable in South and East Asia. Current "Jiaobai" cultivars exhibit abundant variation in their gall formation date; however, the underlying mechanism is not clear. In this study, a strict short-day (SD) "Jiaobai" line "YD-3" was used. Plants were treated with two day-length regimes [14 h/10 h (day/night) (control) and 8 h/16 h (day/night) (SD)] from 100 to 130 days after planting. The gall swelling rate of the two treatments and another early SD treatment (from 60 to 90 days after planting), together with the contingent flowering plants in the experiment population, revealed that SD can improve both gall enlargement and flowering of "Jiaobai" plants. Comparison of RNA sequencing data among control, SD swelling, and SD flowering treatments of leaves and meristems indicated that SD promotion of "Jiaobai" swelling is conducted by the CONSTANS (CO)-FLOWERING LOCUS T (FT) pathway, similar but not identical to the SD-induced flowering pathway in Z latifolia and rice. "Virus-induced gene silencing", "Yeast one-hybrid assay" and "Dual-luciferase assay" showed that a FT gene, ZlGsd1, is critical in SD promotion of gall formation and is positively regulated by a CO gene, ZlCOL1. Our study elucidated how photoperiod affects the formation of a unique organ produced by plant-fungus symbiosis. The difference in SD response between "Jiaobai" and rice, as well as their potential applications in breeding of "Jiaobai" and rice, were also discussed.

11.
PLoS Pathog ; 19(3): e1011225, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36893187

RESUMEN

Animals are under constant selective pressure from a myriad of diverse pathogens. Microsporidia are ubiquitous animal parasites, but the influence they exert on shaping animal genomes is mostly unknown. Using multiplexed competition assays, we measured the impact of four different species of microsporidia on 22 wild isolates of Caenorhabditis elegans. This resulted in the identification and confirmation of 13 strains with significantly altered population fitness profiles under infection conditions. One of these identified strains, JU1400, is sensitive to an epidermal-infecting species by lacking tolerance to infection. JU1400 is also resistant to an intestinal-infecting species and can specifically recognize and destroy this pathogen. Genetic mapping of JU1400 demonstrates that these two opposing phenotypes are caused by separate loci. Transcriptional analysis reveals the JU1400 sensitivity to epidermal microsporidia infection results in a response pattern that shares similarity to toxin-induced responses. In contrast, we do not observe JU1400 intestinal resistance being regulated at the transcriptional level. The transcriptional response to these four microsporidia species is conserved, with C. elegans strain-specific differences in potential immune genes. Together, our results show that phenotypic differences to microsporidia infection amongst C. elegans are common and that animals can evolve species-specific genetic interactions.


Asunto(s)
Proteínas de Caenorhabditis elegans , Microsporidios , Microsporidiosis , Animales , Microsporidios/genética , Caenorhabditis elegans , Interacciones Huésped-Patógeno/genética , Microsporidiosis/veterinaria , Proteínas de Caenorhabditis elegans/genética
12.
Nat Chem Biol ; 19(5): 614-623, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36702958

RESUMEN

Bacterial pathogens rapidly change and adapt their proteome to cope with the environment in host cells and secrete effector proteins to hijack host targets and ensure their survival and proliferation during infection. Excessive host proteins make it difficult to profile pathogens' proteome dynamics by conventional proteomics. It is even more challenging to map pathogen-host protein-protein interactions in real time, given the low abundance of bacterial effectors and weak and transient interactions in which they may be involved. Here we report a method for selectively labeling bacterial proteomes using a bifunctional amino acid, photo-ANA, equipped with a bio-orthogonal handle and a photoreactive warhead, which enables simultaneous analysis of bacterial proteome reprogramming and pathogen-host protein interactions of Salmonella enterica serovar Typhimurium (S. Typhimurium) during infection. Using photo-ANA, we identified FLOT1/2 as host interactors of S. Typhimurium effector PipB2 in late-stage infection and globally profiled the extensive interactions between host proteins and pathogens during infection.


Asunto(s)
Proteínas Bacterianas , Proteoma , Proteoma/metabolismo , Proteínas Bacterianas/metabolismo , Salmonella typhimurium/metabolismo , Interacciones Huésped-Patógeno
13.
J Cell Mol Med ; 28(8): e18201, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38568078

RESUMEN

Sensory nerves play a crucial role in maintaining bone homeostasis by releasing Semaphorin 3A (Sema3A). However, the specific mechanism of Sema3A in regulation of bone marrow mesenchymal stem cells (BMMSCs) during bone remodelling remains unclear. The tibial denervation model was used and the denervated tibia exhibited significantly lower mass as compared to sham operated bones. In vitro, BMMSCs cocultured with dorsal root ganglion cells (DRGs) or stimulated by Sema3A could promote osteogenic differentiation through the Wnt/ß-catenin/Nrp1 positive feedback loop, and the enhancement of osteogenic activity could be inhibited by SM345431 (Sema3A-specific inhibitor). In addition, Sema3A-stimulated BMMSCs or intravenous injection of Sema3A could promote new bone formation in vivo. To sum up, the coregulation of bone remodelling is due to the ageing of BMMSCs and increased osteoclast activity. Furthermore, the sensory neurotransmitter Sema3A promotes osteogenic differentiation of BMMSCs via Wnt/ß-catenin/Nrp1 positive feedback loop, thus promoting osteogenesis in vivo and in vitro.


Asunto(s)
Células Madre Mesenquimatosas , Osteogénesis , Osteogénesis/genética , Semaforina-3A/genética , Retroalimentación , beta Catenina , Ganglios Espinales , Neuropilina-1/genética
14.
J Am Chem Soc ; 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39293040

RESUMEN

A Pd-catalyzed asymmetric higher-order dipolar cycloaddition between allenyl carbonates and azadienes is achieved by exploiting novel alkylidene-π-allyl-Pd dipoles. This research provides a modular platform for the synthesis of challenging chiral endocyclic allenes bearing a medium-sized heterocyclic motif and a centrally chiral stereocenter in good yields with high enantio- and diastereoselectivities (29 examples, up to 97% yield, 97:3 er and >19:1 dr). Experimental and computational studies elucidate the possible reaction mechanism and the observed stereochemical results. Based on the mechanistic understanding, a new π-propargyl-Pd dipole was designed to further extend the success of the higher order dipolar cycloaddition strategy to the synthesis of 10-membered endocyclic alkynes from propargyl carbonates and azadienes (13 examples, up to 98% yield and 94.5:5.5 er).

15.
J Hepatol ; 80(5): 778-791, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38237865

RESUMEN

BACKGROUND & AIMS: Endoplasmic reticulum (ER) stress of hepatocytes plays a causative role in non-alcoholic fatty liver disease (NAFLD). Reduced expression of hepatic nuclear factor 4α (HNF4α) is a critical event in the pathogenesis of NAFLD and other liver diseases. Whether ER stress regulates HNF4α expression remains unknown. The aim of this study was to delineate the machinery of HNF4α protein degradation and explore a therapeutic strategy based on protecting HNF4α stability during NAFLD progression. METHODS: Correlation of HNF4α and tribbles homologue 3 (TRIB3), an ER stress sensor, was evaluated in human and mouse NAFLD tissues. RNA-sequencing, mass spectrometry analysis, co-immunoprecipitation, in vivo and in vitro ubiquitination assays were used to elucidate the mechanisms of TRIB3-mediated HNF4α degradation. Molecular docking and co-immunoprecipitation analyses were performed to identify a cell-penetrating peptide that ablates the TRIB3-HNF4α interaction. RESULTS: TRIB3 directly interacts with HNF4α and mediates ER stress-induced HNF4α degradation. TRIB3 recruits tripartite motif containing 8 (TRIM8) to form an E3 ligase complex that catalyzes K48-linked polyubiquitination of HNF4α on lysine 470. Abrogating the degradation of HNF4α attenuated the effect of TRIB3 on a diet-induced NAFLD model. Moreover, the TRIB3 gain-of-function variant p.Q84R is associated with NAFLD progression in patients, and induces lower HNF4α levels and more severe hepatic steatosis in mice. Importantly, disrupting the TRIB3-HNF4α interaction using a cell-penetrating peptide restores HNF4α levels and ameliorates NAFLD progression in mice. CONCLUSIONS: Our findings unravel the machinery of HNF4α protein degradation and indicate that targeting TRIB3-TRIM8 E3 complex-mediated HNF4α polyubiquitination may be an ideal strategy for NAFLD therapy. IMPACT AND IMPLICATIONS: Reduced expression of hepatic nuclear factor 4α (HNF4α) is a critical event in the pathogenesis of NAFLD and other liver diseases. However, the mechanism of HNF4α protein degradation remains unknown. Herein, we reveal that TRIB3-TRIM8 E3 ligase complex is responsible for HNF4α degradation during NAFLD. Inhibiting the TRIB3-HNF4α interaction effectively stabilized HNF4α protein levels and transcription factor activity in the liver and ameliorated TRIB3-mediated NAFLD progression. Our findings demonstrate that disturbing the TRIM8-TRIB3-HNF4α interaction may provide a novel approach to treat NAFLD and even other liver diseases by stabilizing the HNF4α protein.


Asunto(s)
Péptidos de Penetración Celular , Enfermedad del Hígado Graso no Alcohólico , Proteínas Serina-Treonina Quinasas , Animales , Humanos , Ratones , Proteínas Portadoras/metabolismo , Proteínas de Ciclo Celular/metabolismo , Péptidos de Penetración Celular/metabolismo , Hígado/patología , Simulación del Acoplamiento Molecular , Proteínas del Tejido Nervioso , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Represoras , Ubiquitina-Proteína Ligasas/metabolismo
16.
Anal Chem ; 96(25): 10451-10458, 2024 06 25.
Artículo en Inglés | MEDLINE | ID: mdl-38860917

RESUMEN

Rapid and sensitive RNA detection is of great value in diverse areas, ranging from biomedical research to clinical diagnostics. Existing methods for RNA detection often rely on reverse transcription (RT) and DNA amplification or involve a time-consuming procedure and poor sensitivity. Herein, we proposed a CRISPR/Cas12a-enabled amplification-free assay for rapid, specific, and sensitive RNA diagnostics. This assay, which we termed T7/G4-CRISPR, involved the use of a T7-powered nucleic acid circuit to convert a single RNA target into numerous DNA activators via toehold-mediated strand displacement reaction and T7 exonuclease-mediated target recycling amplification, followed by activating Cas12a trans-cleavage of the linker strands inhibiting split G-Quadruplex (G4) assembly, thereby inducing fluorescence attenuation proportion to the input RNA target. We first performed step-by-step validation of the entire assay process and optimized the reaction parameters. Using the optimal conditions, T7/G4-CRISPR was capable of detecting as low as 3.6 pM target RNA, obtaining ∼100-fold improvement in sensitivity compared with the most direct Cas12a assays. Meanwhile, its excellent specificity could discriminate single nucleotide variants adjacent to the toehold region and allow species-specific pathogen identification. Furthermore, we applied it for analyzing bacterial 16S rRNA in 40 clinical urine samples, exhibiting a sensitivity of 90% and a specificity of 100% when validated by RT-quantitative PCR. Therefore, we envision that T7/G4-CRISPR will serve as a promising RNA sensing approach to expand the toolbox of CRISPR-based diagnostics.


Asunto(s)
Sistemas CRISPR-Cas , G-Cuádruplex , Sistemas CRISPR-Cas/genética , Humanos , Exodesoxirribonucleasas/metabolismo , Exodesoxirribonucleasas/química , ARN/análisis , ARN/metabolismo , Técnicas de Amplificación de Ácido Nucleico , Proteínas Asociadas a CRISPR/metabolismo , Proteínas Bacterianas , Endodesoxirribonucleasas
17.
Curr Genet ; 70(1): 16, 2024 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-39276284

RESUMEN

Histidine kinases (HKs) are important sensor proteins in fungi and play an essential role in environmental adaptation. However, the mechanisms by which fungi sense and respond to fungivores attack via HKs are not fully understood. In this study, we utilized Neurospora crassa to investigate the involvement of HKs in responding to fungivores attack. We found that the 11 HKs in N. crassa not only affected the growth and development, but also led to fluctuations in antioxidant production. Ten mutants in the genes encoding HKs (except ∆phy1) showed increased production of reactive oxygen species (ROS), especially upon Sinella curviseta attack. The ROS burst triggered changes in conidia and perithecial beaks formation, as well as accumulation of ß-glucan, ergothioneine, ergosterol, and carotenoids. ß-glucan was increased in ∆hk9, ∆os1, ∆hcp1, ∆nik2, ∆sln1, ∆phy1 and ∆phy2 mutants compared to the wild-type strain. In parallel, ergothioneine accumulation was improved in ∆phy1 and ∆hk16 mutants and further increased upon attack, except in ∆os1 and ∆hk16 mutants. Additionally, fungivores attack stimulated ergosterol and dehydroergosterol production in ∆hk9 and ∆os1 mutants. Furthermore, deletion of these genes altered carotenoid accumulation, with wild-type strain, ∆hk9, ∆os1, ∆hcp1, ∆sln1, ∆phy2, and ∆dcc1mutants showing an increase in carotenoids upon attack. Taken together, HKs are involved in regulating the production of conidia and antioxidants. Thus, HKs may act as sensors of fungivores attack and effectively improve the adaptive capacity of fungi to environmental stimuli.


Asunto(s)
Histidina Quinasa , Neurospora crassa , Especies Reactivas de Oxígeno , Neurospora crassa/genética , Neurospora crassa/metabolismo , Histidina Quinasa/genética , Histidina Quinasa/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Esporas Fúngicas/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Animales , Regulación Fúngica de la Expresión Génica , Artrópodos/genética , Artrópodos/microbiología , Mutación , Adaptación Fisiológica/genética , Ergosterol/metabolismo , beta-Glucanos/metabolismo , Antioxidantes/metabolismo , Carotenoides/metabolismo , Ergotioneína
18.
BMC Plant Biol ; 24(1): 860, 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39266968

RESUMEN

BACKGROUND: Cardamine violifolia is a significant Brassicaceae plant known for its high selenium (Se) accumulation capacity, serving as an essential source of Se for both humans and animals. WRKY transcription factors play crucial roles in plant responses to various biotic and abiotic stresses, including cadmium stress, iron deficiency, and Se tolerance. However, the molecular mechanism of CvWRKY in Se accumulation is not completely clear. RESULTS: In this study, 120 WRKYs with conserved domains were identified from C. violifolia and classified into three groups based on phylogenetic relationships, with Group II further subdivided into five subgroups. Gene structure analysis revealed WRKY variations and mutations within the CvWRKYs. Segmental duplication events were identified as the primary driving force behind the expansion of the CvWRKY family, with numerous stress-responsive cis-acting elements found in the promoters of CvWRKYs. Transcriptome analysis of plants treated with exogenous Se and determination of Se levels revealed a strong positive correlation between the expression levels of CvWRKY034 and the Se content. Moreover, CvWRKY021 and CvWRKY099 exhibited high homology with AtWRKY47, a gene involved in regulating Se accumulation in Arabidopsis thaliana. The WRKY domains of CvWRKY021 and AtWRKY47 were highly conserved, and transcriptome data analysis revealed that CvWRKY021 responded to Na2SeO4 induction, showing a positive correlation with the concentration of Na2SeO4 treatment. Under the induction of Na2SeO3, CvWRKY021 and CvWRKY034 were significantly upregulated in the roots but downregulated in the shoots, and the Se content in the roots increased significantly and was mainly concentrated in the roots. CvWRKY021 and CvWRKY034 may be involved in the accumulation of Se in roots. CONCLUSIONS: The results of this study elucidate the evolution of CvWRKYs in the C. violifolia genome and provide valuable resources for further understanding the functional characteristics of WRKYs related to Se hyperaccumulation in C. violifolia.


Asunto(s)
Cardamine , Regulación de la Expresión Génica de las Plantas , Filogenia , Proteínas de Plantas , Selenio , Factores de Transcripción , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Cardamine/genética , Cardamine/metabolismo , Selenio/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Genes de Plantas , Perfilación de la Expresión Génica
19.
J Antimicrob Chemother ; 79(1): 128-133, 2024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-37991189

RESUMEN

OBJECTIVES: We explored the epidemiological and molecular characteristics of Candida parapsilosis sensu stricto isolates in China, and their mechanisms of azole resistance. METHODS: Azole susceptibilities of 2318 non-duplicate isolates were determined using CLSI broth microdilution. Isolates were genotyped by a microsatellite typing method. Molecular resistance mechanisms were also studied and functionally validated by CRISPR/Cas9-based genetic alterations. RESULTS: Fluconazole resistance occurred in 2.4% (n = 56) of isolates, and these isolates showed a higher frequency of distribution in ICU inpatients compared with susceptible isolates (48.2%, n = 27/56 versus 27.8%, 613/2208; P = 0.019). Microsatellite-genotyping analysis yielded 29 genotypes among 56 fluconazole-resistant isolates, of which 10 genotypes, including 37 isolates, belonged to clusters, persisting and transmitting in Chinese hospitals for 1-29 months. Clusters harbouring Erg11Y132F (5/10; 50%) were predominant in China. Among these, the second most dominant cluster MT07, including seven isolates, characteristically harbouring Erg11Y132F and Mrr1Q625K, lent its carriage to being one of the strongest associations with cross-resistance and high MICs of fluconazole (>256 mg/L) and voriconazole (2-8 mg/L), causing transmission across two hospitals. Among mutations tested, Mrr1Q625K led to the highest-level increase of fluconazole MIC (32-fold), while mutations located within or near the predicted transcription factor domain of Tac1 (D440Y, T492M and L518F) conferred cross-resistance to azoles. CONCLUSIONS: This study is the first Chinese report of persistence and transmissions of multiple fluconazole-resistant C. parapsilosis sensu stricto clones harbouring Erg11Y132F, and the first demonstration of the mutations Erg11G307A, Mrr1Q625K, Tac1L263S, Tac1D440Y and Tac1T492M as conferring resistance to azoles.


Asunto(s)
Candida parapsilosis , Fluconazol , Fluconazol/farmacología , Candida parapsilosis/genética , Antifúngicos/farmacología , Azoles/farmacología , China/epidemiología , Pruebas de Sensibilidad Microbiana , Farmacorresistencia Fúngica/genética
20.
Int J Obes (Lond) ; 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38926462

RESUMEN

BACKGROUND: The obesity paradox has been reported among older adults. However, whether the favorable effect of obesity is dependent on metabolic status remains largely unknown. We aimed to explore the association of metabolic obesity phenotypes and their changes with all-cause mortality among the Chinese oldest-old population. METHODS: This prospective cohort study included 1207 Chinese oldest old (mean age: 91.8 years). Metabolic obesity phenotypes were determined by central obesity and metabolic status, and participants were classified into metabolically healthy obesity (MHO), metabolically unhealthy obesity (MUO), metabolically healthy non-obesity (MHN), and metabolically unhealthy non-obesity (MUN). The hazard ratios (HRs) and 95% confidence intervals (95% CIs) were estimated by Cox regression models. RESULTS: During 5.3 years of follow-up, 640 deaths were documented. Compared with non-obesity, obesity was associated with a decreased mortality risk among participants with metabolically healthy (HR, 0.75; 95% CI, 0.63-0.91) while this association was insignificant among metabolically unhealthy. Compared to MHO, MHN (HR, 1.27; 95% CI, 1.06-1.53) and MUN (HR, 1.49; 95% CI, 1.10-2.02) were significantly associated with an increased mortality risk. Compared to those with stable MHO, those transited from MHO to MUO demonstrated a higher mortality risk (HR, 1.81; 95% CI, 1.06-3.11). CONCLUSIONS: MHO predicts better survival among the Chinese oldest-old population. These findings suggest that ensuring optimal management of metabolic health is beneficial and taking caution in weight loss based on the individual body weight for the metabolically healthy oldest-old adults.

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