Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.432
Filtrar
Más filtros

Intervalo de año de publicación
1.
Cell ; 184(13): 3542-3558.e16, 2021 06 24.
Artículo en Inglés | MEDLINE | ID: mdl-34051138

RESUMEN

Structural variations (SVs) and gene copy number variations (gCNVs) have contributed to crop evolution, domestication, and improvement. Here, we assembled 31 high-quality genomes of genetically diverse rice accessions. Coupling with two existing assemblies, we developed pan-genome-scale genomic resources including a graph-based genome, providing access to rice genomic variations. Specifically, we discovered 171,072 SVs and 25,549 gCNVs and used an Oryza glaberrima assembly to infer the derived states of SVs in the Oryza sativa population. Our analyses of SV formation mechanisms, impacts on gene expression, and distributions among subpopulations illustrate the utility of these resources for understanding how SVs and gCNVs shaped rice environmental adaptation and domestication. Our graph-based genome enabled genome-wide association study (GWAS)-based identification of phenotype-associated genetic variations undetectable when using only SNPs and a single reference assembly. Our work provides rich population-scale resources paired with easy-to-access tools to facilitate rice breeding as well as plant functional genomics and evolutionary biology research.


Asunto(s)
Ecotipo , Variación Genética , Genoma de Planta , Oryza/genética , Adaptación Fisiológica/genética , Agricultura , Domesticación , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Variación Estructural del Genoma , Anotación de Secuencia Molecular , Fenotipo
2.
Nat Immunol ; 22(12): 1590-1598, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34811538

RESUMEN

Although critical to T cell function, antigen specificity is often omitted in high-throughput multiomics-based T cell profiling due to technical challenges. We describe a high-dimensional, tetramer-associated T cell antigen receptor (TCR) sequencing (TetTCR-SeqHD) method to simultaneously profile cognate antigen specificities, TCR sequences, targeted gene expression and surface-protein expression from tens of thousands of single cells. Using human polyclonal CD8+ T cells with known antigen specificity and TCR sequences, we demonstrate over 98% precision for detecting the correct antigen specificity. We also evaluate gene expression and phenotypic differences among antigen-specific CD8+ T cells and characterize phenotype signatures of influenza- and Epstein-Barr virus-specific CD8+ T cells that are unique to their pathogen targets. Moreover, with the high-throughput capacity of profiling hundreds of antigens simultaneously, we apply TetTCR-SeqHD to identify antigens that preferentially enrich cognate CD8+ T cells in patients with type 1 diabetes compared to healthy controls and discover a TCR that cross-reacts with diabetes-related and microbiome antigens. TetTCR-SeqHD is a powerful approach for profiling T cell responses in humans and mice.


Asunto(s)
Antígenos/inmunología , Linfocitos T CD8-positivos/inmunología , Secuenciación de Nucleótidos de Alto Rendimiento , Receptores de Antígenos de Linfocitos T/genética , Análisis de la Célula Individual , Antígenos/metabolismo , Antígenos Virales/inmunología , Antígenos Virales/metabolismo , Autoantígenos/inmunología , Autoantígenos/metabolismo , Autoinmunidad , Linfocitos T CD8-positivos/metabolismo , Linfocitos T CD8-positivos/virología , Estudios de Casos y Controles , Separación Celular , Células Cultivadas , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/inmunología , Diabetes Mellitus Tipo 1/metabolismo , Herpesvirus Humano 4/inmunología , Herpesvirus Humano 4/patogenicidad , Humanos , Orthomyxoviridae/inmunología , Orthomyxoviridae/patogenicidad , Fenotipo , Receptores de Antígenos de Linfocitos T/inmunología , Receptores de Antígenos de Linfocitos T/metabolismo
3.
Nature ; 606(7916): 945-952, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35732742

RESUMEN

Amyotrophic lateral sclerosis (ALS) is a heterogenous neurodegenerative disorder that affects motor neurons and voluntary muscle control1. ALS heterogeneity includes the age of manifestation, the rate of progression and the anatomical sites of symptom onset. Disease-causing mutations in specific genes have been identified and define different subtypes of ALS1. Although several ALS-associated genes have been shown to affect immune functions2, whether specific immune features account for ALS heterogeneity is poorly understood. Amyotrophic lateral sclerosis-4 (ALS4) is characterized by juvenile onset and slow progression3. Patients with ALS4 show motor difficulties by the time that they are in their thirties, and most of them require devices to assist with walking by their fifties. ALS4 is caused by mutations in the senataxin gene (SETX). Here, using Setx knock-in mice that carry the ALS4-causative L389S mutation, we describe an immunological signature that consists of clonally expanded, terminally differentiated effector memory (TEMRA) CD8 T cells in the central nervous system and the blood of knock-in mice. Increased frequencies of antigen-specific CD8 T cells in knock-in mice mirror the progression of motor neuron disease and correlate with anti-glioma immunity. Furthermore, bone marrow transplantation experiments indicate that the immune system has a key role in ALS4 neurodegeneration. In patients with ALS4, clonally expanded TEMRA CD8 T cells circulate in the peripheral blood. Our results provide evidence of an antigen-specific CD8 T cell response in ALS4, which could be used to unravel disease mechanisms and as a potential biomarker of disease state.


Asunto(s)
Esclerosis Amiotrófica Lateral , Linfocitos T CD8-positivos , Células Clonales , Esclerosis Amiotrófica Lateral/inmunología , Esclerosis Amiotrófica Lateral/patología , Animales , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/patología , Células Clonales/patología , ADN Helicasas/genética , ADN Helicasas/metabolismo , Técnicas de Sustitución del Gen , Ratones , Neuronas Motoras/patología , Enzimas Multifuncionales/genética , Enzimas Multifuncionales/metabolismo , Mutación , ARN Helicasas/genética , ARN Helicasas/metabolismo
4.
Immunol Rev ; 316(1): 120-135, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37209375

RESUMEN

Human T cells have a diverse T-cell receptor (TCR) repertoire that endows them with the ability to identify and defend against a broad spectrum of antigens. The universe of possible antigens that T cells may encounter, however, is even larger. To effectively surveil such a vast universe, the T-cell repertoire must adopt a high degree of cross-reactivity. Likewise, antigen-specific and cross-reactive T-cell responses play pivotal roles in both protective and pathological immune responses in numerous diseases. In this review, we explore the implications of these antigen-driven T-cell responses, with a particular focus on CD8+ T cells, using infection, neurodegeneration, and cancer as examples. We also summarize recent technological advances that facilitate high-throughput profiling of antigen-specific and cross-reactive T-cell responses experimentally, as well as computational biology approaches that predict these interactions.


Asunto(s)
Antígenos , Linfocitos T CD8-positivos , Humanos , Reacciones Cruzadas , Receptores de Antígenos de Linfocitos T
5.
Nat Methods ; 20(4): 590-599, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36928074

RESUMEN

Our understanding of nerve regeneration can be enhanced by delineating its underlying molecular activities at single-neuron resolution in model organisms such as Caenorhabditis elegans. Existing cell isolation techniques cannot isolate neurons with specific regeneration phenotypes from C. elegans. We present femtosecond laser microdissection (fs-LM), a single-cell isolation method that dissects specific cells directly from living tissue by leveraging the micrometer-scale precision of fs-laser ablation. We show that fs-LM facilitates sensitive and specific gene expression profiling by single-cell RNA sequencing (scRNA-seq), while mitigating the stress-related transcriptional artifacts induced by tissue dissociation. scRNA-seq of fs-LM isolated regenerating neurons revealed transcriptional programs that are correlated with either successful or failed regeneration in wild-type and dlk-1 (0) animals, respectively. This method also allowed studying heterogeneity displayed by the same type of neuron and found gene modules with expression patterns correlated with axon regrowth rate. Our results establish fs-LM as a spatially resolved single-cell isolation method for phenotype-to-genotype mapping.


Asunto(s)
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Animales , Caenorhabditis elegans/genética , Microdisección/métodos , Neuronas/fisiología , Rayos Láser , Análisis de Secuencia de ARN , Quinasas Quinasa Quinasa PAM , Proteínas de Caenorhabditis elegans/genética
6.
Circ Res ; 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38957991

RESUMEN

BACKGROUND: Cerebral vascular malformations (CCMs) are primarily found within the brain, where they result in increased risk for stroke, seizures, and focal neurological deficits. The unique feature of the brain vasculature is the blood-brain barrier formed by the brain neurovascular unit. Recent studies suggest that loss of CCM genes causes disruptions of blood-brain barrier integrity as the inciting events for CCM development. CCM lesions are proposed to be initially derived from a single clonal expansion of a subset of angiogenic venous capillary endothelial cells (ECs) and respective resident endothelial progenitor cells (EPCs). However, the critical signaling events in the subclass of brain ECs/EPCs for CCM lesion initiation and progression are unclear. METHODS: Brain EC-specific CCM3-deficient (Pdcd10BECKO) mice were generated by crossing Pdcd10fl/fl mice with Mfsd2a-CreERT2 mice. Single-cell RNA-sequencing analyses were performed by the chromium single-cell platform (10× genomics). Cell clusters were annotated into EC subtypes based on visual inspection and GO analyses. Cerebral vessels were visualized by 2-photon in vivo imaging and tissue immunofluorescence analyses. Regulation of mTOR (mechanistic target of rapamycin) signaling by CCM3 and Cav1 (caveolin-1) was performed by cell biology and biochemical approaches. RESULTS: Single-cell RNA-sequencing analyses from P10 Pdcd10BECKO mice harboring visible CCM lesions identified upregulated CCM lesion signature and mitotic EC clusters but decreased blood-brain barrier-associated EC clusters. However, a unique EPC cluster with high expression levels of stem cell markers enriched with mTOR signaling was identified from early stages of the P6 Pdcd10BECKO brain. Indeed, mTOR signaling was upregulated in both mouse and human CCM lesions. Genetic deficiency of Raptor (regulatory-associated protein of mTOR), but not of Rictor (rapamycin-insensitive companion of mTOR), prevented CCM lesion formation in the Pdcd10BECKO model. Importantly, the mTORC1 (mTOR complex 1) pharmacological inhibitor rapamycin suppressed EPC proliferation and ameliorated CCM pathogenesis in Pdcd10BECKO mice. Mechanistic studies suggested that Cav1/caveolae increased in CCM3-depleted EPC-mediated intracellular trafficking and complex formation of the mTORC1 signaling proteins. CONCLUSIONS: CCM3 is critical for maintaining blood-brain barrier integrity and CCM3 loss-induced mTORC1 signaling in brain EPCs initiates and facilitates CCM pathogenesis.

7.
Nature ; 580(7801): 93-99, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32238934

RESUMEN

Prostate cancer is the second most common cancer in men worldwide1. Over the past decade, large-scale integrative genomics efforts have enhanced our understanding of this disease by characterizing its genetic and epigenetic landscape in thousands of patients2,3. However, most tumours profiled in these studies were obtained from patients from Western populations. Here we produced and analysed whole-genome, whole-transcriptome and DNA methylation data for 208 pairs of tumour tissue samples and matched healthy control tissue from Chinese patients with primary prostate cancer. Systematic comparison with published data from 2,554 prostate tumours revealed that the genomic alteration signatures in Chinese patients were markedly distinct from those of Western cohorts: specifically, 41% of tumours contained mutations in FOXA1 and 18% each had deletions in ZNF292 and CHD1. Alterations of the genome and epigenome were correlated and were predictive of disease phenotype and progression. Coding and noncoding mutations, as well as epimutations, converged on pathways that are important for prostate cancer, providing insights into this devastating disease. These discoveries underscore the importance of including population context in constructing comprehensive genomic maps for disease.


Asunto(s)
Pueblo Asiatico/genética , Epigénesis Genética , Epigenómica , Genoma Humano/genética , Genómica , Mutación , Neoplasias de la Próstata/clasificación , Neoplasias de la Próstata/genética , Proteínas Portadoras/genética , Transformación Celular Neoplásica/genética , China , Estudios de Cohortes , ADN Helicasas/genética , Metilación de ADN , Proteínas de Unión al ADN/genética , Regulación Neoplásica de la Expresión Génica , Factor Nuclear 3-alfa del Hepatocito/genética , Humanos , Masculino , Proteínas del Tejido Nervioso/genética , Neoplasias de la Próstata/patología , RNA-Seq , Transcriptoma/genética
8.
Mol Cell Proteomics ; 23(6): 100769, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38641227

RESUMEN

The understanding of dynamic plasma proteome features in hybrid immunity and breakthrough infection is limited. A deeper understanding of the immune differences between heterologous and homologous immunization could assist in the future establishment of vaccination strategies. In this study, 40 participants who received a third dose of either a homologous BBIBP-CorV or a heterologous ZF2001 protein subunit vaccine following two doses of inactivated coronavirus disease 2019 vaccines and 12 patients with BA2.2 breakthrough infections were enrolled. Serum samples were collected at days 0, 28, and 180 following the boosting vaccination and breakthrough and then analyzed using neutralizing antibody tests and mass spectrometer-based proteomics. Mass cytometry of peripheral blood mononuclear cell samples was also performed in this cohort. The chemokine signaling pathway and humoral response markers (IgG2 and IgG3) associated with infection were found to be upregulated in breakthrough infections compared to vaccination-induced immunity. Elevated expression of IGKV, IGHV, IL-17 signaling, and the phagocytosis pathway, along with lower expression of FGL2, were correlated with higher antibody levels in the boosting vaccination groups. The MAPK signaling pathway and Fc gamma R-mediated phagocytosis were more enriched in the heterologous immunization groups than in the homologous immunization groups. Breakthrough infections can trigger more intensive inflammatory chemokine responses than vaccination. T-cell and innate immune activation have been shown to be closely related to enhanced antibody levels after vaccination and therefore might be potential targets for vaccine adjuvant design.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Proteómica , SARS-CoV-2 , Humanos , Proteómica/métodos , COVID-19/prevención & control , COVID-19/inmunología , SARS-CoV-2/inmunología , Femenino , Vacunas contra la COVID-19/inmunología , Vacunas contra la COVID-19/administración & dosificación , Masculino , Estudios Longitudinales , Adulto , Anticuerpos Neutralizantes/inmunología , Anticuerpos Neutralizantes/sangre , Persona de Mediana Edad , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , Inmunización Secundaria , Vacunación , Estudios de Cohortes , Proteoma , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Infección Irruptiva
9.
Proc Natl Acad Sci U S A ; 120(28): e2217301120, 2023 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-37399423

RESUMEN

A common event upon receptor-ligand engagement is the formation of receptor clusters on the cell surface, in which signaling molecules are specifically recruited or excluded to form signaling hubs to regulate cellular events. These clusters are often transient and can be disassembled to terminate signaling. Despite the general relevance of dynamic receptor clustering in cell signaling, the regulatory mechanism underlying the dynamics is still poorly understood. As a major antigen receptor in the immune system, T cell receptors (TCR) form spatiotemporally dynamic clusters to mediate robust yet temporal signaling to induce adaptive immune responses. Here we identify a phase separation mechanism controlling dynamic TCR clustering and signaling. The TCR signaling component CD3ε chain can condensate with Lck kinase through phase separation to form TCR signalosomes for active antigen signaling. Lck-mediated CD3ε phosphorylation, however, switched its binding preference to Csk, a functional suppressor of Lck, to cause the dissolvement of TCR signalosomes. Modulating TCR/Lck condensation by targeting CD3ε interactions with Lck or Csk directly affects T cell activation and function, highlighting the importance of the phase separation mechanism. The self-programmed condensation and dissolvement is thus a built-in mechanism of TCR signaling and might be relevant to other receptors.


Asunto(s)
Proteína Tirosina Quinasa p56(lck) Específica de Linfocito , Receptores de Antígenos de Linfocitos T , Transducción de Señal/fisiología , Fosforilación , Antígenos/metabolismo
10.
J Biol Chem ; 300(1): 105538, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38072046

RESUMEN

Histone chaperone FACT (facilitates chromatin transcription) is well known to promote chromatin recovery during transcription. However, the mechanism how FACT regulates genome-wide chromatin accessibility and transcription factor binding has not been fully elucidated. Through loss-of-function studies, we show here that FACT component Ssrp1 is required for DNA replication and DNA damage repair and is also essential for progression of cell phase transition and cell proliferation in mouse embryonic fibroblast cells. On the molecular level, absence of the Ssrp1 leads to increased chromatin accessibility, enhanced CTCF binding, and a remarkable change in dynamic range of gene expression. Our study thus unequivocally uncovers a unique mechanism by which FACT complex regulates transcription by coordinating genome-wide chromatin accessibility and CTCF binding.


Asunto(s)
Factor de Unión a CCCTC , Cromatina , Proteínas de Unión al ADN , Regulación de la Expresión Génica , Proteínas del Grupo de Alta Movilidad , Chaperonas de Histonas , Animales , Ratones , Factor de Unión a CCCTC/genética , Factor de Unión a CCCTC/metabolismo , Cromatina/genética , Replicación del ADN , Chaperonas de Histonas/genética , Proteínas de Unión al ADN/genética , Proteínas del Grupo de Alta Movilidad/genética , Células 3T3 NIH , Reparación del ADN
11.
Plant J ; 119(2): 720-734, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38713838

RESUMEN

The RNA regulatory network is a complex and dynamic regulation in plant cells involved in mRNA modification, translation, and degradation. Ras-GAP SH3 domain-binding protein (G3BP) is a scaffold protein for the assembly of stress granules (SGs) and is considered an antiviral component in mammals. However, the function of G3BP during virus infection in plants is still largely unknown. In this study, four members of the G3BP-like proteins (NtG3BPLs) were identified in Nicotiana tabacum and the expression levels of NtG3BPL1 were upregulated during chilli veinal mottle virus (ChiVMV) infection. NtG3BPL1 was localized in the nucleus and cytoplasm, forming cytoplasmic granules under transient high-temperature treatment, whereas the abundance of cytoplasmic granules was decreased under ChiVMV infection. Overexpression of NtG3BPL1 inhibited ChiVMV infection and delayed the onset of symptoms, whereas knockout of NtG3BPL1 promoted ChiVMV infection. In addition, NtG3BPL1 directly interacted with ChiVMV 6K2 protein, whereas 6K2 protein had no effect on NtG3BPL1-derived cytoplasmic granules. Further studies revealed that the expression of NtG3BPL1 reduced the chloroplast localization of 6K2-GFP and the NtG3BPL1-6K2 interaction complex was localized in the cytoplasm. Furthermore, NtG3BPL1 promoted the degradation of 6K2 through autophagy pathway, and the accumulation of 6K2 and ChiVMV was affected by autophagy activation or inhibition in plants. Taken together, our results demonstrate that NtG3BPL1 plays a positive role in tobacco resistance against ChiVMV infection, revealing a novel mechanism of plant G3BP in antiviral strategy.


Asunto(s)
Nicotiana , Enfermedades de las Plantas , Proteínas de Plantas , Nicotiana/virología , Nicotiana/genética , Nicotiana/metabolismo , Enfermedades de las Plantas/virología , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Resistencia a la Enfermedad/genética , Regulación de la Expresión Génica de las Plantas , Plantas Modificadas Genéticamente , Potyvirus/fisiología
12.
Plant Physiol ; 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38652695

RESUMEN

Centromeres in most multicellular eukaryotes are composed of long arrays of repetitive DNA sequences. Interestingly, several transposable elements, including the well-known long terminal repeat (LTR) retrotransposon CRM (centromeric retrotransposon of maize), were found to be enriched in functional centromeres marked by the centromeric histone H3 (CENH3). Here we report a centromeric long interspersed nuclear element (LINE), Celine, in Populus species. Celine has colonized preferentially in the CENH3-associated chromatin of every poplar chromosome, with 84% of the Celine elements localized in the CENH3-binding domains. By contrast, only 51% of the CRM elements were bound to CENH3 domains in Populus trichocarpa. These results suggest different centromere targeting mechanisms employed by Celine and CRM elements. Nevertheless, the high target specificity seems to be detrimental to further amplification of the Celine elements, leading to a shorter life span and patchy distribution among plant species compared to the CRM elements. Using a phylogenetically guided approach we were able to identify Celine-like LINE elements in tea plant (Camellia sinensis) and green ash tree (Fraxinus pennsylvanica). The centromeric localization of these Celine-like LINEs was confirmed in both species. We demonstrate that the centromere targeting property of Celine-like LINEs is of primitive origin and has been conserved among distantly related plant species.

13.
J Infect Dis ; 229(6): 1711-1721, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38149984

RESUMEN

BACKGROUND: Low-frequency intrahost single-nucleotide variants of SARS-CoV-2 have been recognized as predictive indicators of selection. However, the impact of vaccination on the intrahost evolution of SARS-CoV-2 remains uncertain at present. METHODS: We investigated the genetic variation of SARS-CoV-2 in individuals who were unvaccinated, partially vaccinated, or fully vaccinated during Shanghai's Omicron BA.2.2 wave. We substantiated the connection between particular amino acid substitutions and immune-mediated selection through a pseudovirus neutralization assay or by cross-verification with the human leukocyte antigen-associated T-cell epitopes. RESULTS: In contrast to those with immunologic naivety or partial vaccination, participants who were fully vaccinated had intrahost variant spectra characterized by reduced diversity. Nevertheless, the distribution of mutations in the fully vaccinated group was enriched in the spike protein. The distribution of intrahost single-nucleotide variants in individuals who were immunocompetent did not demonstrate notable signs of positive selection, in contrast to the observed adaptation in 2 participants who were immunocompromised who had an extended period of viral shedding. CONCLUSIONS: In SARS-CoV-2 infections, vaccine-induced immunity was associated with decreased diversity of within-host variant spectra, with milder inflammatory pathophysiology. The enrichment of mutations in the spike protein gene indicates selection pressure exerted by vaccination on the evolution of SARS-CoV-2.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus , Vacunación , Humanos , SARS-CoV-2/inmunología , SARS-CoV-2/genética , COVID-19/inmunología , COVID-19/prevención & control , COVID-19/virología , Vacunas contra la COVID-19/inmunología , Vacunas contra la COVID-19/administración & dosificación , China , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/inmunología , Epítopos de Linfocito T/inmunología , Epítopos de Linfocito T/genética , Mutación , Sustitución de Aminoácidos , Variación Genética , Masculino , Femenino , Infección Irruptiva
14.
J Clin Immunol ; 44(6): 131, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38775840

RESUMEN

RHOH, an atypical small GTPase predominantly expressed in hematopoietic cells, plays a vital role in immune function. A deficiency in RHOH has been linked to epidermodysplasia verruciformis, lung disease, Burkitt lymphoma and T cell defects. Here, we report a novel germline homozygous RHOH c.245G > A (p.Cys82Tyr) variant in a 21-year-old male suffering from recurrent, invasive, opportunistic infections affecting the lungs, eyes, and brain. His sister also succumbed to a lung infection during early adulthood. The patient exhibited a persistent decrease in CD4+ T, B, and NK cell counts, and hypoimmunoglobulinemia. The patient's T cell showed impaired activation upon in vitro TCR stimulation. In Jurkat T cells transduced with RHOHC82Y, a similar reduction in activation marker CD69 up-regulation was observed. Furthermore, the C82Y variant showed reduced RHOH protein expression and impaired interaction with the TCR signaling molecule ZAP70. Together, these data suggest that the newly identified autosomal-recessive RHOH variant is associated with T cell dysfunction and recurrent opportunistic infections, functioning as a hypomorph by disrupting ZAP70-mediated TCR signaling.


Asunto(s)
Homocigoto , Infecciones Oportunistas , Humanos , Masculino , Adulto Joven , Células Jurkat , Activación de Linfocitos/genética , Infecciones Oportunistas/genética , Infecciones Oportunistas/inmunología , Linaje , Receptores de Antígenos de Linfocitos T/genética , Receptores de Antígenos de Linfocitos T/metabolismo , Recurrencia , Linfocitos T/inmunología , Proteína Tirosina Quinasa ZAP-70/genética , Proteína Tirosina Quinasa ZAP-70/metabolismo
15.
Hum Brain Mapp ; 45(5): e26573, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38544416

RESUMEN

Humans can extract high-level spatial features from visual signals, but spatial representations in the brain are complex and remain unclear. The unsupervised capsule neural network (U-CapsNet) is sensitive to the spatial location and relationship of the object, contains a special recurrent mechanism and uses a self-supervised generation strategy to represent images, which is similar to the computational principle in the human brain. Therefore, we hypothesized that U-CapsNet can help us understand how the human brain processes spatial information. First, brain activities were studied using functional magnetic resonance imaging during spatial working memory in which participants had to remember the locations of circles for a short time. Then, U-CapsNet served as a computational model of the brain to perform tasks that are identical to those performed by humans. Finally, the representational models were used to compare the U-CapsNet with the brain. The results showed that some human-defined spatial features naturally emerged in the latent space of U-CapsNet. Moreover, representations in U-CapsNet captured the response structure of two types of brain regions during different activity patterns, as well as important factors associated with human behavior. Together, our study not only provides a computationally feasible framework for modeling how the human brain encodes spatial features but also provides insights into the representational format and goals of the human brain.


Asunto(s)
Mapeo Encefálico , Encéfalo , Humanos , Mapeo Encefálico/métodos , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Recuerdo Mental , Memoria a Corto Plazo , Redes Neurales de la Computación , Imagen por Resonancia Magnética
16.
Small ; : e2403211, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38958082

RESUMEN

Prussian blue analogs (PBAs) have been widely recognized as superior cathode materials for sodium-ion batteries (SIBs) owing to numerous merits. However, originating from the rapid crystal growth, PBAs still suffer from considerable vacancy defects and interstitial water, making the preparation of long-cycle-life PBAs the greatest challenge for its practical application. Herein, a novel equilibrium chelation strategy is first proposed to synthesize a high crystallinity (94.7%) PBAs, which is realized by modulating the chelating potency of strong chelating agents via "acid effect" to achieve a moderate chelating effect, forcefully breaking through the bottleneck of poor cyclic stability for PBAs cathodes. Impressively, the as-prepared highly crystalline PBAs represent an unprecedented level of electrochemical performance including ultra-long lifespan (10000 cycles with 86.32% capacity maintenance at 6 A g-1), excellent rate capability (82.0 mAh g-1 at 6 A g-1). Meanwhile, by pairing with commercial hard carbon, the as-prepared PBAs-based SIBs exhibit high energy density (350 Wh kg-1) and excellent capacity retention (82.4% after 1500 cycles), highlighting its promising potential for large-scale energy storage applications.

17.
Small ; 20(26): e2308681, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38234151

RESUMEN

Na4Fe3(PO4)2(P2O7) (NFPP) has been considered a promising cathode material for sodium-ion batteries (SIBs) owing to its environmental friendliness and economic viability. However, its electrochemical performance is constrained by connatural low electronic conductivity and inadequate sodium ion diffusion. Herein, a high-entropy substitution strategy is employed in NFPP to address these limitations. Ex situ X-ray diffraction analysis reveals a single-phase electrochemical reaction during the sodiation/desodiation processes and the increased configurational entropy in HE-NFPP endows an enhanced structure, which results in a minimal volume variation of only 1.83%. Kinetic analysis and density functional theory calculation further confirm that the orbital hybrid synergy of high-entropy transition metals offers a favorable electronic structure, which efficaciously boosts the charge transfer kinetics and optimizes the sodium ion diffusion channel. Based on this versatile strategy, the as-prepared high-entropy Na4Fe2.5Mn0.1Mg0.1Co0.1Ni0.1Cu0.1(PO4)2(P2O7) (HE-NFPP) cathode can deliver a prominent rate performance of 55 mAh g-1 at 10 A g-1 and an ultra-long cycling lifespan of over 18 000 cycles at 5 A g-1. When paired with a hard carbon (HC) anode, HE-NFPP//HC full cell exhibits a favorable cycling durability of 1000 cycles. This high-entropy engineering offers a feasible route to improve the electrochemical performance of NFPP and provides a blueprint for exploring high-performance SIBs.

18.
J Transl Med ; 22(1): 73, 2024 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-38238834

RESUMEN

BACKGROUND: The role of mitochondrial dynamics, encompassing fission, fusion, and mitophagy, in cancer progression has been extensively studied. However, the specific impact of mitochondrial dynamics on hepatocellular carcinoma (HCC) is still under investigation. METHODS: In this study, mitochondrial dynamic genes were obtained from the MitoCarta 3.0 database, and gene expression data were collected from The Cancer Genome Atlas (TCGA) database. Based on the expression of these dynamic genes and differentially expressed genes (DEGs), patients were stratified into two clusters. Subsequently, a prognostic model was constructed using univariate COX regression and the least absolute shrinkage and selection operator (LASSO) regression, and the prognostic signature was evaluated. We analyzed the interaction between these model genes and dynamic genes to identify hub genes and reveal mitochondrial status. Furthermore, we assessed immune infiltration, tumor mutational burden (TMB), tumor stemness indices (TSI), and the response to immune checkpoint block (ICB) therapy using the TIDE algorithm and risk scores. Additionally, transmission electron microscopy (TEM), hematoxylin-eosin (H&E) staining, immunohistochemistry (IHC), western blotting (WB), and immunofluorescence (IF) were conducted to afford detailed visualization of the morphology of the mitochondria and the expression patterns of fission-associated proteins. RESULTS: Patients in Cluster 2 exhibited heightened mitochondrial fission and had a worse prognosis. The up-regulated dynamic genes in Cluster 2 were identified as fission genes. GO/KEGG analyses reconfirmed the connection of Cluster 2 to augmented mitochondrial fission activities. Subsequently, a ten-gene prognostic signature based on the differentially expressed genes between the two clusters was generated, with all ten genes being up-regulated in the high-risk group. Moreover, the potential links between these ten signature genes and mitochondrial dynamics were explored, suggesting their involvement in mediating mitochondrial fission through interaction with MTFR2. Further investigation revealed that the high-risk group had an unfavorable prognosis, with a higher mutation frequency of TP53, increased immune checkpoint expression, a higher TIS score, and a lower TIDE score. The mitochondrial imbalance characterized by increased fission and upregulated MTFR2 and DNM1L expression was substantiated in both HCC specimens and cell lines. CONCLUSIONS: In conclusion, we developed a novel MTFR2-related prognostic signature comprising ten mitochondrial dynamics genes. These genes play crucial roles in mitochondrial fission and have the potential to serve as important predictors and therapeutic targets for HCC.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Algoritmos , Carcinoma Hepatocelular/genética , Línea Celular , Neoplasias Hepáticas/genética , Dinámicas Mitocondriales/genética , Pronóstico
19.
J Transl Med ; 22(1): 52, 2024 01 13.
Artículo en Inglés | MEDLINE | ID: mdl-38217021

RESUMEN

Osteoarthritis (OA) is a chronic degenerative disease resulting joint disability and pain. Accumulating evidences suggest that chondrocyte extracellular matrix calcification plays an important role in the development of OA. Here, we showed that Krüppel-like factor 10 (Klf10) was involved in the regulation of chondrocyte extracellular matrix calcification by regulating the expression of Frizzled9. Knockdown of Klf10 attenuated TBHP induced calcification and reduced calcium content in chondrocytes. Restoring extracellular matrix calcification of chondrocytes could aggravate chondrocyte senescence. Destabilization of a medial meniscus (DMM) mouse model of OA, in vivo experiments revealed that knockdown Klf10 improved the calcification of articular cartilage and ameliorated articular cartilage degeneration. These findings suggested that knockdown Klf10 inhibited extracellular matrix calcification-related changes in chondrocytes and alleviated chondrocyte senescence.


Asunto(s)
Calcinosis , Cartílago Articular , Osteoartritis , Animales , Ratones , Calcinosis/genética , Cartílago Articular/metabolismo , Condrocitos/metabolismo , Matriz Extracelular/metabolismo , Osteoartritis/genética
20.
Opt Lett ; 49(8): 1965-1968, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38621052

RESUMEN

We propose a concise hardware architecture supporting efficient exclusive OR (XOR) and exclusive NOR (XNOR) operations, by employing a single photonic spiking neuron based on a passive add-drop microring resonator (ADMRR). The threshold mechanism and inhibitory dynamics of the ADMRR-based spiking neuron are numerically discussed on the basis of the coupled mode theory. It is shown that a precise XOR operation in the ADMRR-based spiking neuron can be implemented by adjusting temporal differences within the inhibitory window. Additionally, within the same framework, the XNOR function can also be carried out by accumulating the input power over time to trigger an excitatory behavior. This work presents a novel, to the best of our knowledge, and pragmatic technique for optical neuromorphic computing and information processing utilizing passive devices.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA