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1.
Cell ; 187(21): 5998-6015.e18, 2024 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-39191257

RESUMO

Internal states drive survival behaviors, but their neural implementation is poorly understood. Recently, we identified a line attractor in the ventromedial hypothalamus (VMH) that represents a state of aggressiveness. Line attractors can be implemented by recurrent connectivity or neuromodulatory signaling, but evidence for the latter is scant. Here, we demonstrate that neuropeptidergic signaling is necessary for line attractor dynamics in this system by using cell-type-specific CRISPR-Cas9-based gene editing combined with single-cell calcium imaging. Co-disruption of receptors for oxytocin and vasopressin in adult VMH Esr1+ neurons that control aggression diminished attack, reduced persistent neural activity, and eliminated line attractor dynamics while only slightly reducing overall neural activity and sex- or behavior-specific tuning. These data identify a requisite role for neuropeptidergic signaling in implementing a behaviorally relevant line attractor in mammals. Our approach should facilitate mechanistic studies in neuroscience that bridge different levels of biological function and abstraction.


Assuntos
Neurônios , Neuropeptídeos , Transdução de Sinais , Animais , Neuropeptídeos/metabolismo , Neuropeptídeos/genética , Camundongos , Masculino , Feminino , Neurônios/metabolismo , Sistemas CRISPR-Cas/genética , Ocitocina/metabolismo , Hipotálamo/metabolismo , Edição de Genes , Receptores de Vasopressinas/metabolismo , Receptores de Vasopressinas/genética , Camundongos Endogâmicos C57BL , Receptor alfa de Estrogênio/metabolismo
2.
Cell ; 2024 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-39454574

RESUMO

Elucidating organismal developmental processes requires a comprehensive understanding of cellular lineages in the spatial, temporal, and molecular domains. In this study, we introduce Zebrahub, a dynamic atlas of zebrafish embryonic development that integrates single-cell sequencing time course data with lineage reconstructions facilitated by light-sheet microscopy. This atlas offers high-resolution and in-depth molecular insights into zebrafish development, achieved through the sequencing of individual embryos across ten developmental stages, complemented by reconstructions of cellular trajectories. Zebrahub also incorporates an interactive tool to navigate the complex cellular flows and lineages derived from light-sheet microscopy data, enabling in silico fate-mapping experiments. To demonstrate the versatility of our multimodal resource, we utilize Zebrahub to provide fresh insights into the pluripotency of neuro-mesodermal progenitors (NMPs) and the origins of a joint kidney-hemangioblast progenitor population.

3.
Cell ; 186(1): 178-193.e15, 2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-36608653

RESUMO

The hypothalamus regulates innate social behaviors, including mating and aggression. These behaviors can be evoked by optogenetic stimulation of specific neuronal subpopulations within MPOA and VMHvl, respectively. Here, we perform dynamical systems modeling of population neuronal activity in these nuclei during social behaviors. In VMHvl, unsupervised analysis identified a dominant dimension of neural activity with a large time constant (>50 s), generating an approximate line attractor in neural state space. Progression of the neural trajectory along this attractor was correlated with an escalation of agonistic behavior, suggesting that it may encode a scalable state of aggressiveness. Consistent with this, individual differences in the magnitude of the integration dimension time constant were strongly correlated with differences in aggressiveness. In contrast, approximate line attractors were not observed in MPOA during mating; instead, neurons with fast dynamics were tuned to specific actions. Thus, different hypothalamic nuclei employ distinct neural population codes to represent similar social behaviors.


Assuntos
Comportamento Sexual Animal , Núcleo Hipotalâmico Ventromedial , Animais , Comportamento Sexual Animal/fisiologia , Núcleo Hipotalâmico Ventromedial/fisiologia , Hipotálamo/fisiologia , Agressão/fisiologia , Comportamento Social
4.
Cell ; 184(10): 2649-2664.e18, 2021 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-33848463

RESUMO

Receptor tyrosine kinase (RTK)-mediated activation of downstream effector pathways such as the RAS GTPase/MAP kinase (MAPK) signaling cascade is thought to occur exclusively from lipid membrane compartments in mammalian cells. Here, we uncover a membraneless, protein granule-based subcellular structure that can organize RTK/RAS/MAPK signaling in cancer. Chimeric (fusion) oncoproteins involving certain RTKs including ALK and RET undergo de novo higher-order assembly into membraneless cytoplasmic protein granules that actively signal. These pathogenic biomolecular condensates locally concentrate the RAS activating complex GRB2/SOS1 and activate RAS in a lipid membrane-independent manner. RTK protein granule formation is critical for oncogenic RAS/MAPK signaling output in these cells. We identify a set of protein granule components and establish structural rules that define the formation of membraneless protein granules by RTK oncoproteins. Our findings reveal membraneless, higher-order cytoplasmic protein assembly as a distinct subcellular platform for organizing oncogenic RTK and RAS signaling.


Assuntos
Condensados Biomoleculares/metabolismo , Grânulos Citoplasmáticos/metabolismo , Neoplasias/metabolismo , Proteínas de Fusão Oncogênica/metabolismo , Proteínas ras/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Ativação Enzimática , Proteína Adaptadora GRB2/genética , Proteína Adaptadora GRB2/metabolismo , Células HEK293 , Humanos , Proteína SOS1/metabolismo , Transdução de Sinais
5.
Cell ; 173(5): 1265-1279.e19, 2018 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-29775595

RESUMO

Chronic social isolation causes severe psychological effects in humans, but their neural bases remain poorly understood. 2 weeks (but not 24 hr) of social isolation stress (SIS) caused multiple behavioral changes in mice and induced brain-wide upregulation of the neuropeptide tachykinin 2 (Tac2)/neurokinin B (NkB). Systemic administration of an Nk3R antagonist prevented virtually all of the behavioral effects of chronic SIS. Conversely, enhancing NkB expression and release phenocopied SIS in group-housed mice, promoting aggression and converting stimulus-locked defensive behaviors to persistent responses. Multiplexed analysis of Tac2/NkB function in multiple brain areas revealed dissociable, region-specific requirements for both the peptide and its receptor in different SIS-induced behavioral changes. Thus, Tac2 coordinates a pleiotropic brain state caused by SIS via a distributed mode of action. These data reveal the profound effects of prolonged social isolation on brain chemistry and function and suggest potential new therapeutic applications for Nk3R antagonists.


Assuntos
Encéfalo/metabolismo , Neurocinina B/metabolismo , Precursores de Proteínas/metabolismo , Isolamento Social , Estresse Psicológico , Taquicininas/metabolismo , Animais , Antipsicóticos/farmacologia , Comportamento Animal/efeitos dos fármacos , Encéfalo/patologia , Feminino , Vetores Genéticos/administração & dosagem , Vetores Genéticos/genética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Neurocinina B/genética , Neurônios/citologia , Neurônios/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Precursores de Proteínas/antagonistas & inibidores , Precursores de Proteínas/genética , Interferência de RNA , RNA Interferente Pequeno/genética , Receptores de Taquicininas/antagonistas & inibidores , Receptores de Taquicininas/metabolismo , Taquicininas/antagonistas & inibidores , Taquicininas/genética , Regulação para Cima/efeitos dos fármacos
6.
Cell ; 167(3): 843-857.e14, 2016 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-27720451

RESUMO

Glucagon and thyroid hormone (T3) exhibit therapeutic potential for metabolic disease but also exhibit undesired effects. We achieved synergistic effects of these two hormones and mitigation of their adverse effects by engineering chemical conjugates enabling delivery of both activities within one precisely targeted molecule. Coordinated glucagon and T3 actions synergize to correct hyperlipidemia, steatohepatitis, atherosclerosis, glucose intolerance, and obesity in metabolically compromised mice. We demonstrate that each hormonal constituent mutually enriches cellular processes in hepatocytes and adipocytes via enhanced hepatic cholesterol metabolism and white fat browning. Synchronized signaling driven by glucagon and T3 reciprocally minimizes the inherent harmful effects of each hormone. Liver-directed T3 action offsets the diabetogenic liability of glucagon, and glucagon-mediated delivery spares the cardiovascular system from adverse T3 action. Our findings support the therapeutic utility of integrating these hormones into a single molecular entity that offers unique potential for treatment of obesity, type 2 diabetes, and cardiovascular disease.


Assuntos
Glucagon/uso terapêutico , Doenças Metabólicas/tratamento farmacológico , Tri-Iodotironina/efeitos dos fármacos , Animais , Aterosclerose/tratamento farmacológico , Peso Corporal/efeitos dos fármacos , Osso e Ossos/efeitos dos fármacos , Engenharia Química/métodos , Colesterol/metabolismo , Diabetes Mellitus Tipo 2/tratamento farmacológico , Modelos Animais de Doenças , Combinação de Medicamentos , Sistemas de Liberação de Medicamentos , Sinergismo Farmacológico , Glucagon/efeitos adversos , Glucagon/química , Glucagon/farmacologia , Hiperglicemia/tratamento farmacológico , Fígado/efeitos dos fármacos , Fígado/metabolismo , Camundongos , Terapia de Alvo Molecular , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Obesidade/tratamento farmacológico , Tri-Iodotironina/efeitos adversos , Tri-Iodotironina/química , Tri-Iodotironina/farmacologia
7.
Cell ; 163(1): 230-45, 2015 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-26365490

RESUMO

Embryonic stem cells (ESCs) repress the expression of exogenous proviruses and endogenous retroviruses (ERVs). Here, we systematically dissected the cellular factors involved in provirus repression in embryonic carcinomas (ECs) and ESCs by a genome-wide siRNA screen. Histone chaperones (Chaf1a/b), sumoylation factors (Sumo2/Ube2i/Sae1/Uba2/Senp6), and chromatin modifiers (Trim28/Eset/Atf7ip) are key determinants that establish provirus silencing. RNA-seq analysis uncovered the roles of Chaf1a/b and sumoylation modifiers in the repression of ERVs. ChIP-seq analysis demonstrates direct recruitment of Chaf1a and Sumo2 to ERVs. Chaf1a reinforces transcriptional repression via its interaction with members of the NuRD complex (Kdm1a, Hdac1/2) and Eset, while Sumo2 orchestrates the provirus repressive function of the canonical Zfp809/Trim28/Eset machinery by sumoylation of Trim28. Our study reports a genome-wide atlas of functional nodes that mediate proviral silencing in ESCs and illuminates the comprehensive, interconnected, and multi-layered genetic and epigenetic mechanisms by which ESCs repress retroviruses within the genome.


Assuntos
Células-Tronco Embrionárias/virologia , Retrovirus Endógenos/genética , Provírus/genética , Animais , Fator 1 de Modelagem da Cromatina/genética , Fator 1 de Modelagem da Cromatina/metabolismo , Células-Tronco de Carcinoma Embrionário/virologia , Epigênese Genética , Camundongos , Proteínas Modificadoras Pequenas Relacionadas à Ubiquitina/metabolismo
8.
Cell ; 158(4): 945-958, 2014 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-25088144

RESUMO

Understanding the structure-function relationships at cellular, circuit, and organ-wide scale requires 3D anatomical and phenotypical maps, currently unavailable for many organs across species. At the root of this knowledge gap is the absence of a method that enables whole-organ imaging. Herein, we present techniques for tissue clearing in which whole organs and bodies are rendered macromolecule-permeable and optically transparent, thereby exposing their cellular structure with intact connectivity. We describe PACT (passive clarity technique), a protocol for passive tissue clearing and immunostaining of intact organs; RIMS (refractive index matching solution), a mounting media for imaging thick tissue; and PARS (perfusion-assisted agent release in situ), a method for whole-body clearing and immunolabeling. We show that in rodents PACT, RIMS, and PARS are compatible with endogenous-fluorescence, immunohistochemistry, RNA single-molecule FISH, long-term storage, and microscopy with cellular and subcellular resolution. These methods are applicable for high-resolution, high-content mapping and phenotyping of normal and pathological elements within intact organs and bodies.


Assuntos
Células/classificação , Imageamento Tridimensional/métodos , Análise de Célula Única , Imagem Corporal Total , Animais , Encéfalo/citologia , Células/metabolismo , Fluorescência , Camundongos , Microscopia Confocal/métodos , Microscopia Eletrônica de Varredura , Fenótipo
9.
Nature ; 608(7924): 741-749, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35922505

RESUMO

Mating and aggression are innate social behaviours that are controlled by subcortical circuits in the extended amygdala and hypothalamus1-4. The bed nucleus of the stria terminalis (BNSTpr) is a node that receives input encoding sex-specific olfactory cues from the medial amygdala5,6, and which in turn projects to hypothalamic nuclei that control mating7-9 (medial preoptic area (MPOA)) and aggression9-14 (ventromedial hypothalamus, ventrolateral subdivision (VMHvl)), respectively15. Previous studies have demonstrated that male aromatase-positive BNSTpr neurons are required for mounting and attack, and may identify conspecific sex according to their overall level of activity16. However, neural representations in BNSTpr, their function and their transformations in the hypothalamus have not been characterized. Here we performed calcium imaging17,18 of male BNSTprEsr1 neurons during social behaviours. We identify distinct populations of female- versus male-tuned neurons in BNSTpr, with the former outnumbering the latter by around two to one, similar to the medial amygdala and MPOA but opposite to VMHvl, in which male-tuned neurons predominate6,9,19. Chemogenetic silencing of BNSTprEsr1 neurons while imaging MPOAEsr1 or VMHvlEsr1 neurons in behaving animals showed, unexpectedly, that the male-dominant sex-tuning bias in VMHvl was inverted to female-dominant whereas a switch from sniff- to mount-selective neurons during mating was attenuated in MPOA. Our data also indicate that BNSTprEsr1 neurons are not essential for conspecific sex identification. Rather, they control the transition from appetitive to consummatory phases of male social behaviours by shaping sex- and behaviour-specific neural representations in the hypothalamus.


Assuntos
Comportamento Sexual Animal , Comportamento Social , Agressão/fisiologia , Tonsila do Cerebelo/citologia , Tonsila do Cerebelo/fisiologia , Animais , Cálcio/análise , Cálcio/metabolismo , Feminino , Hipotálamo/citologia , Hipotálamo/fisiologia , Masculino , Neurônios/fisiologia , Área Pré-Óptica/citologia , Área Pré-Óptica/fisiologia , Caracteres Sexuais , Comportamento Sexual Animal/fisiologia
10.
Nature ; 606(7913): 358-367, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35477154

RESUMO

The composition of the intestinal microbiome varies considerably between individuals and is correlated with health1. Understanding the extent to which, and how, host genetics contributes to this variation is essential yet has proved to be difficult, as few associations have been replicated, particularly in humans2. Here we study the effect of host genotype on the composition of the intestinal microbiota in a large mosaic pig population. We show that, under conditions of exacerbated genetic diversity and environmental uniformity, microbiota composition and the abundance of specific taxa are heritable. We map a quantitative trait locus affecting the abundance of Erysipelotrichaceae species and show that it is caused by a 2.3 kb deletion in the gene encoding N-acetyl-galactosaminyl-transferase that underpins the ABO blood group in humans. We show that this deletion is a ≥3.5-million-year-old trans-species polymorphism under balancing selection. We demonstrate that it decreases the concentrations of N-acetyl-galactosamine in the gut, and thereby reduces the abundance of Erysipelotrichaceae that can import and catabolize N-acetyl-galactosamine. Our results provide very strong evidence for an effect of the host genotype on the abundance of specific bacteria in the intestine combined with insights into the molecular mechanisms that underpin this association. Our data pave the way towards identifying the same effect in rural human populations.


Assuntos
Sistema ABO de Grupos Sanguíneos , Acetilgalactosamina , Microbioma Gastrointestinal , Genótipo , Suínos , Sistema ABO de Grupos Sanguíneos/genética , Acetilgalactosamina/metabolismo , Animais , Bactérias/isolamento & purificação , Microbioma Gastrointestinal/genética , N-Acetilgalactosaminiltransferases/metabolismo , Locos de Características Quantitativas , Suínos/genética , Suínos/microbiologia
11.
Nature ; 589(7841): 258-263, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33268894

RESUMO

Animal behaviours that are superficially similar can express different intents in different contexts, but how this flexibility is achieved at the level of neural circuits is not understood. For example, males of many species can exhibit mounting behaviour towards same- or opposite-sex conspecifics1, but it is unclear whether the intent and neural encoding of these behaviours are similar or different. Here we show that female- and male-directed mounting in male laboratory mice are distinguishable by the presence or absence of ultrasonic vocalizations (USVs)2-4, respectively. These and additional behavioural data suggest that most male-directed mounting is aggressive, although in rare cases it can be sexual. We investigated whether USV+ and USV- mounting use the same or distinct hypothalamic neural substrates. Micro-endoscopic imaging of neurons positive for oestrogen receptor 1 (ESR1) in either the medial preoptic area (MPOA) or the ventromedial hypothalamus, ventrolateral subdivision (VMHvl) revealed distinct patterns of neuronal activity during USV+ and USV- mounting, and the type of mounting could be decoded from population activity in either region. Intersectional optogenetic stimulation of MPOA neurons that express ESR1 and vesicular GABA transporter (VGAT) (MPOAESR1∩VGAT neurons) robustly promoted USV+ mounting, and converted male-directed attack to mounting with USVs. By contrast, stimulation of VMHvl neurons that express ESR1 (VMHvlESR1 neurons) promoted USV- mounting, and inhibited the USVs evoked by female urine. Terminal stimulation experiments suggest that these complementary inhibitory effects are mediated by reciprocal projections between the MPOA and VMHvl. Together, these data identify a hypothalamic subpopulation that is genetically enriched for neurons that causally induce a male reproductive behavioural state, and indicate that reproductive and aggressive states are represented by distinct population codes distributed between MPOAESR1 and VMHvlESR1 neurons, respectively. Thus, similar behaviours that express different internal states are encoded by distinct hypothalamic neuronal populations.


Assuntos
Agressão/fisiologia , Hipotálamo/citologia , Hipotálamo/fisiologia , Comportamento Sexual Animal/fisiologia , Animais , Copulação , Receptor alfa de Estrogênio/metabolismo , Feminino , Homossexualidade Masculina , Masculino , Camundongos , Optogenética , Área Pré-Óptica/metabolismo , Proteínas Vesiculares de Transporte de Aminoácidos Inibidores/metabolismo
12.
Proc Natl Acad Sci U S A ; 121(15): e2310291121, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38564641

RESUMO

Humans blink their eyes frequently during normal viewing, more often than it seems necessary for keeping the cornea well lubricated. Since the closure of the eyelid disrupts the image on the retina, eye blinks are commonly assumed to be detrimental to visual processing. However, blinks also provide luminance transients rich in spatial information to neural pathways highly sensitive to temporal changes. Here, we report that the luminance modulations from blinks enhance visual sensitivity. By coupling high-resolution eye tracking in human observers with modeling of blink transients and spectral analysis of visual input signals, we show that blinking increases the power of retinal stimulation and that this effect significantly enhances visibility despite the time lost in exposure to the external scene. We further show that, as predicted from the spectral content of input signals, this enhancement is selective for stimuli at low spatial frequencies and occurs irrespective of whether the luminance transients are actively generated or passively experienced. These findings indicate that, like eye movements, blinking acts as a computational component of a visual processing strategy that uses motor behavior to reformat spatial information into the temporal domain.


Assuntos
Piscadela , Movimentos Oculares , Humanos , Estimulação Luminosa , Percepção Visual/fisiologia , Visão Ocular
13.
Proc Natl Acad Sci U S A ; 121(32): e2404536121, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39088396

RESUMO

Alcelaphine gammaherpesvirus 1 (AlHV-1) asymptomatically persists in its natural host, the wildebeest. However, cross-species transmission to cattle results in the induction of an acute and lethal peripheral T cell lymphoma-like disease (PTCL), named malignant catarrhal fever (MCF). Our previous findings demonstrated an essential role for viral genome maintenance in infected CD8+ T lymphocytes but the exact mechanism(s) leading to lymphoproliferation and MCF remained unknown. To decipher how AlHV-1 dysregulates T lymphocytes, we first examined the global phenotypic changes in circulating CD8+ T cells after experimental infection of calves. T cell receptor repertoire together with transcriptomics and epigenomics analyses demonstrated an oligoclonal expansion of infected CD8+ T cells displaying effector and exhaustion gene signatures, including GZMA, GNLY, PD-1, and TOX2 expression. Then, among viral genes expressed in infected CD8+ T cells, we uncovered A10 that encodes a transmembrane signaling protein displaying multiple tyrosine residues, with predicted ITAM and SH3 motifs. Impaired A10 expression did not affect AlHV-1 replication in vitro but rendered AlHV-1 unable to induce MCF. Furthermore, A10 was phosphorylated in T lymphocytes in vitro and affected T cell signaling. Finally, while AlHV-1 mutants expressing mutated forms of A10 devoid of ITAM or SH3 motifs (or both) were able to induce MCF, a recombinant virus expressing a mutated form of A10 unable to phosphorylate its tyrosine residues resulted in the lack of MCF and protected against a wild-type virus challenge. Thus, we could characterize the nature of this γ-herpesvirus-induced PTCL-like disease and identify an essential mechanism explaining its development.


Assuntos
Linfócitos T CD8-Positivos , Gammaherpesvirinae , Animais , Linfócitos T CD8-Positivos/imunologia , Gammaherpesvirinae/genética , Gammaherpesvirinae/imunologia , Bovinos , Febre Catarral Maligna/virologia , Febre Catarral Maligna/imunologia , Infecções por Herpesviridae/imunologia , Infecções por Herpesviridae/virologia
14.
Brief Bioinform ; 25(3)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38678388

RESUMO

Cyclic peptides offer a range of notable advantages, including potent antibacterial properties, high binding affinity and specificity to target molecules, and minimal toxicity, making them highly promising candidates for drug development. However, a comprehensive database that consolidates both synthetically derived and naturally occurring cyclic peptides is conspicuously absent. To address this void, we introduce CyclicPepedia (https://www.biosino.org/iMAC/cyclicpepedia/), a pioneering database that encompasses 8744 known cyclic peptides. This repository, structured as a composite knowledge network, offers a wealth of information encompassing various aspects of cyclic peptides, such as cyclic peptides' sources, categorizations, structural characteristics, pharmacokinetic profiles, physicochemical properties, patented drug applications, and a collection of crucial publications. Supported by a user-friendly knowledge retrieval system and calculation tools specifically designed for cyclic peptides, CyclicPepedia will be able to facilitate advancements in cyclic peptide drug development.


Assuntos
Bases de Conhecimento , Peptídeos Cíclicos , Peptídeos Cíclicos/química , Bases de Dados de Proteínas
15.
PLoS Pathog ; 20(9): e1012483, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39226326

RESUMO

Fibronectin (FN) is an essential component of the extracellular matrix (ECM) that protects the integrity of the microvascular endothelial barrier (MEB). However, Treponema pallidum subsp. pallidum (Tp) breaches this barrier through elusive mechanisms and rapidly disseminates throughout the host. We aimed to understand the impact of Tp on the surrounding FN matrix of MEB and the underlying mechanisms of this effect. In this study, immunofluorescence assays (IF) were conducted to assess the integrity of the FN matrix surrounding human microvascular endothelial cell-1 (HMEC-1) with/without Tp co-culture, revealing that only live Tp exhibited the capability to mediate FN matrix disaggregation in HMEC-1. Western blotting and IF were employed to determine the protein levels associated with the FN matrix during Tp infection, which showed the unaltered protein levels of total FN and its receptor integrin α5ß1, along with reduced insoluble FN and increased soluble FN. Simultaneously, the integrin α5ß1-binding protein-intracellular vimentin maintained a stable total protein level while exhibiting an increase in the soluble form, specifically mediated by the phosphorylation of its 39th residue (pSer39-vimentin). Besides, this process of vimentin phosphorylation, which could be hindered by a serine-to-alanine mutation or inhibition of phosphorylated-AKT1 (pAKT1), promoted intracellular vimentin rearrangement and FN matrix disaggregation. Moreover, within the introduction of additional cellular FN rather than other Tp-adhered ECM protein, in vitro endothelial barrier traversal experiment and in vivo syphilitic infectivity test demonstrated that viable Tp was effectively prevented from penetrating the in vitro MEB or disseminating in Tp-challenged rabbits. This investigation revealed the active pAKT1/pSer39-vimentin signal triggered by live Tp to expedite the disaggregation of the FN matrix and highlighted the importance of FN matrix stability in syphilis, thereby providing a novel perspective on ECM disruption mechanisms that facilitate Tp dissemination across the MEB.


Assuntos
Células Endoteliais , Fibronectinas , Treponema pallidum , Vimentina , Fibronectinas/metabolismo , Humanos , Vimentina/metabolismo , Treponema pallidum/metabolismo , Animais , Fosforilação , Células Endoteliais/metabolismo , Células Endoteliais/microbiologia , Matriz Extracelular/metabolismo , Sífilis/metabolismo , Sífilis/microbiologia , Coelhos , Endotélio Vascular/metabolismo , Endotélio Vascular/microbiologia
16.
Nucleic Acids Res ; 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39404071

RESUMO

Subcellular localization of RNA is a crucial mechanism for regulating diverse biological processes within cells. Dynamic RNA subcellular localizations are essential for maintaining cellular homeostasis; however, their distribution and changes during development and differentiation remain largely unexplored. To elucidate the dynamic patterns of RNA distribution within cells, we have upgraded RNALocate to version 3.0, a repository for RNA-subcellular localization (http://www.rnalocate.org/ or http://www.rna-society.org/rnalocate/). RNALocate v3.0 incorporates and analyzes RNA subcellular localization sequencing data from over 850 samples, with a specific focus on the dynamic changes in subcellular localizations under various conditions. The species coverage has also been expanded to encompass mammals, non-mammals, plants and microbes. Additionally, we provide an integrated prediction algorithm for the subcellular localization of seven RNA types across eleven subcellular compartments, utilizing convolutional neural networks (CNNs) and transformer models. Overall, RNALocate v3.0 contains a total of 1 844 013 RNA-localization entries covering 26 RNA types, 242 species and 177 subcellular localizations. It serves as a comprehensive and readily accessible data resource for RNA-subcellular localization, facilitating the elucidation of cellular function and disease pathogenesis.

17.
Proc Natl Acad Sci U S A ; 120(12): e2217254120, 2023 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-36917671

RESUMO

The potentiation of antibiotics is a promising strategy for combatting antibiotic-resistant/tolerant bacteria. Herein, we report that a 5-min sublethal heat shock enhances the bactericidal actions of aminoglycoside antibiotics by six orders of magnitude against both exponential- and stationary-phase Escherichia coli. This combined treatment also effectively kills various E. coli persisters, E. coli clinical isolates, and numerous gram-negative but not gram-positive bacteria and enables aminoglycosides at 5% of minimum inhibitory concentrations to eradicate multidrug-resistant pathogens Acinetobacter baumannii and Klebsiella pneumoniae. Mechanistically, the potentiation is achieved comprehensively by heat shock-enhanced proton motive force that thus promotes the bacterial uptake of aminoglycosides, as well as by increasing irreversible protein aggregation and reactive oxygen species that further augment the downstream lethality of aminoglycosides. Consistently, protonophores, chemical chaperones, antioxidants, and anaerobic culturing abolish heat shock-enhanced aminoglycoside lethality. We also demonstrate as a proof of concept that infrared irradiation- or photothermal nanosphere-induced thermal treatments potentiate aminoglycoside killing of Pseudomonas aeruginosa in a mouse acute skin wound model. Our study advances the understanding of the mechanism of actions of aminoglycosides and demonstrates a high potential for thermal ablation in curing bacterial infections when combined with aminoglycosides.


Assuntos
Aminoglicosídeos , Antibacterianos , Camundongos , Animais , Antibacterianos/farmacologia , Antibacterianos/química , Aminoglicosídeos/farmacologia , Aminoglicosídeos/química , Espécies Reativas de Oxigênio/farmacologia , Agregados Proteicos , Escherichia coli , Bactérias Gram-Negativas , Bactérias , Resposta ao Choque Térmico , Testes de Sensibilidade Microbiana
18.
J Biol Chem ; 300(1): 105556, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38097188

RESUMO

A renewable source of porcine macrophages derived from pluripotent stem cells (PSCs) would be a valuable alternative to primary porcine alveolar macrophages (PAMs) in the research of host-pathogen interaction mechanisms. We developed an efficient and rapid protocol, within 11 days, to derive macrophages from porcine PSCs (pPSCs). The pPSC-derived macrophages (pPSCdMs) exhibited molecular and functional characteristics of primary macrophages. The pPSCdMs showed macrophage-specific surface protein expression and macrophage-specific transcription factors, similar to PAMs. The pPSCdMs also exhibited the functional characteristics of macrophages, such as endocytosis, phagocytosis, porcine respiratory and reproductive syndrome virus infection and the response to lipopolysaccharide stimulation. Furthermore, we performed transcriptome sequencing of the whole differentiation process to track the fate transitions of porcine PSCs involved in the signaling pathway. The activation of transforming growth factor beta signaling was required for the formation of mesoderm and the inhibition of the transforming growth factor beta signaling pathway at the hematopoietic endothelium stage could enhance the fate transformation of hematopoiesis. In summary, we developed an efficient and rapid protocol to generate pPSCdMs that showed aspects of functional maturity comparable with PAMs. pPSCdMs could provide a broad prospect for the platforms of host-pathogen interaction mechanisms.


Assuntos
Macrófagos Alveolares , Células-Tronco Pluripotentes , Suínos , Animais , Endocitose , Hematopoese/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Macrófagos Alveolares/citologia , Macrófagos Alveolares/efeitos dos fármacos , Macrófagos Alveolares/metabolismo , Macrófagos Alveolares/virologia , Mesoderma/metabolismo , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/efeitos dos fármacos , Vírus da Síndrome Respiratória e Reprodutiva Suína/fisiologia , Transdução de Sinais/efeitos dos fármacos , Suínos/virologia , Fatores de Transcrição/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Fatores de Tempo
19.
Eur J Immunol ; 54(8): e2350796, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38922884

RESUMO

Tuberculosis (TB) was the leading cause of death from a single infectious agent before the coronavirus pandemic. Therefore, it is important to search for severity biomarkers and devise appropriate therapies. A total of 139 pulmonary TB (PTB) patients and 80 healthy controls (HCs) were recruited for plasma soluble CD137 (sCD137) detection through ELISA. Moreover, pleural effusion sCD137 levels were measured in 85 TB patients and 36 untreated lung cancer patients. The plasma cytokine levels in 64 patients with PTB and blood immune cell subpopulations in 68 patients with PTB were analysed via flow cytometry. Blood sCD137 levels were higher in PTB patients (p = 0.012) and correlated with disease severity (p = 0.0056). The level of sCD137 in tuberculous pleurisy effusion (TPE) was markedly higher than that in malignant pleurisy effusion (p = 0.018). Several blood cytokines, such as IL-6 (p = 0.0147), IL-8 (p = 0.0477), IP-10 (p ≤ 0.0001) and MCP-1 (p = 0.0057), and some laboratory indices were significantly elevated in severe PTB (SE) patients, but the percentages of total lymphocytes (p = 0.002) and cytotoxic T cells (p = 0.036) were significantly lower in SE patients than in non-SE patients. In addition, the sCD137 level was negatively correlated with the percentage of total lymphocytes (p = 0.0008) and cytotoxic T cells (p = 0.0021), and PTB patients with higher plasma sCD137 levels had significantly shorter survival times (p = 0.0041). An increase in sCD137 is a potential biomarker for severe TB and indicates a poor prognosis.


Assuntos
Biomarcadores , Índice de Gravidade de Doença , Tuberculose Pulmonar , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Prognóstico , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/sangue , Adulto , Biomarcadores/sangue , Idoso , Tuberculose Pulmonar/sangue , Tuberculose Pulmonar/imunologia , Tuberculose Pulmonar/mortalidade , Citocinas/sangue , Tuberculose Pleural/imunologia , Tuberculose Pleural/sangue , Tuberculose Pleural/diagnóstico , Tuberculose Pleural/mortalidade
20.
Nat Methods ; 19(4): 461-469, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35314838

RESUMO

The promise of single-objective light-sheet microscopy is to combine the convenience of standard single-objective microscopes with the speed, coverage, resolution and gentleness of light-sheet microscopes. We present DaXi, a single-objective light-sheet microscope design based on oblique plane illumination that achieves: (1) a wider field of view and high-resolution imaging via a custom remote focusing objective; (2) fast volumetric imaging over larger volumes without compromising image quality or necessitating tiled acquisition; (3) fuller image coverage for large samples via multi-view imaging and (4) higher throughput multi-well imaging via remote coverslip placement. Our instrument achieves a resolution of 450 nm laterally and 2 µm axially over an imaging volume of 3,000 × 800 × 300 µm. We demonstrate the speed, field of view, resolution and versatility of our instrument by imaging various systems, including Drosophila egg chamber development, zebrafish whole-brain activity and zebrafish embryonic development - up to nine embryos at a time.


Assuntos
Encéfalo , Peixe-Zebra , Animais , Encéfalo/diagnóstico por imagem , Drosophila , Desenvolvimento Embrionário , Microscopia de Fluorescência/métodos
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