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1.
Nat Immunol ; 25(1): 155-165, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38102487

RESUMO

In mouse peritoneal and other serous cavities, the transcription factor GATA6 drives the identity of the major cavity resident population of macrophages, with a smaller subset of cavity-resident macrophages dependent on the transcription factor IRF4. Here we showed that GATA6+ macrophages in the human peritoneum were rare, regardless of age. Instead, more human peritoneal macrophages aligned with mouse CD206+ LYVE1+ cavity macrophages that represent a differentiation stage just preceding expression of GATA6. A low abundance of CD206+ macrophages was retained in C57BL/6J mice fed a high-fat diet and in wild-captured mice, suggesting that differences between serous cavity-resident macrophages in humans and mice were not environmental. IRF4-dependent mouse serous cavity macrophages aligned closely with human CD1c+CD14+CD64+ peritoneal cells, which, in turn, resembled human peritoneal CD1c+CD14-CD64- cDC2. Thus, major populations of serous cavity-resident mononuclear phagocytes in humans and mice shared common features, but the proportions of different macrophage differentiation stages greatly differ between the two species, and dendritic cell (DC2)-like cells were especially prominent in humans.


Assuntos
Macrófagos Peritoneais , Macrófagos , Humanos , Camundongos , Animais , Camundongos Endogâmicos C57BL , Macrófagos/metabolismo , Macrófagos Peritoneais/metabolismo , Diferenciação Celular , Células Dendríticas
2.
Nat Immunol ; 24(9): 1443-1457, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37563309

RESUMO

Tissue-resident macrophages (TRMs) are long-lived cells that maintain locally and can be phenotypically distinct from monocyte-derived macrophages. Whether TRMs and monocyte-derived macrophages have district roles under differing pathologies is not understood. Here, we showed that a substantial portion of the macrophages that accumulated during pancreatitis and pancreatic cancer in mice had expanded from TRMs. Pancreas TRMs had an extracellular matrix remodeling phenotype that was important for maintaining tissue homeostasis during inflammation. Loss of TRMs led to exacerbation of severe pancreatitis and death, due to impaired acinar cell survival and recovery. During pancreatitis, TRMs elicited protective effects by triggering the accumulation and activation of fibroblasts, which was necessary for initiating fibrosis as a wound healing response. The same TRM-driven fibrosis, however, drove pancreas cancer pathogenesis and progression. Together, these findings indicate that TRMs play divergent roles in the pathogenesis of pancreatitis and cancer through regulation of stromagenesis.


Assuntos
Pâncreas , Pancreatite , Camundongos , Animais , Pâncreas/patologia , Macrófagos , Pancreatite/genética , Pancreatite/patologia , Fibrose , Neoplasias Pancreáticas
3.
Cell ; 182(4): 855-871.e23, 2020 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-32730808

RESUMO

A T cell receptor (TCR) mediates antigen-induced signaling through its associated CD3ε, δ, γ, and ζ, but the contributions of different CD3 chains remain elusive. Using quantitative mass spectrometry, we simultaneously quantitated the phosphorylation of the immunoreceptor tyrosine-based activation motif (ITAM) of all CD3 chains upon TCR stimulation. A subpopulation of CD3ε ITAMs was mono-phosphorylated, owing to Lck kinase selectivity, and specifically recruited the inhibitory Csk kinase to attenuate TCR signaling, suggesting that TCR is a self-restrained signaling machinery containing both activating and inhibitory motifs. Moreover, we found that incorporation of the CD3ε cytoplasmic domain into a second-generation chimeric antigen receptor (CAR) improved antitumor activity of CAR-T cells. Mechanistically, the Csk-recruiting ITAM of CD3ε reduced CAR-T cytokine production whereas the basic residue rich sequence (BRS) of CD3ε promoted CAR-T persistence via p85 recruitment. Collectively, CD3ε is a built-in multifunctional signal tuner, and increasing CD3 diversity represents a strategy to design next-generation CAR.


Assuntos
Complexo CD3/metabolismo , Imunoterapia Adotiva/métodos , Receptores de Antígenos Quiméricos/metabolismo , Transdução de Sinais , Motivos de Aminoácidos , Animais , Complexo CD3/química , Proteína Tirosina Quinase CSK/metabolismo , Linhagem Celular , Citocinas/metabolismo , Humanos , Ativação Linfocitária/efeitos dos fármacos , Proteína Tirosina Quinase p56(lck) Linfócito-Específica/metabolismo , Camundongos , Camundongos Endogâmicos NOD , Neoplasias/mortalidade , Neoplasias/patologia , Neoplasias/terapia , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Análise de Sobrevida , Vanadatos/farmacologia
4.
Cell ; 159(4): 857-68, 2014 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-25417161

RESUMO

Dyneins power microtubule motility using ring-shaped, AAA-containing motor domains. Here, we report X-ray and electron microscopy (EM) structures of yeast dynein bound to different ATP analogs, which collectively provide insight into the roles of dynein's two major ATPase sites, AAA1 and AAA3, in the conformational change mechanism. ATP binding to AAA1 triggers a cascade of conformational changes that propagate to all six AAA domains and cause a large movement of the "linker," dynein's mechanical element. In contrast to the role of AAA1 in driving motility, nucleotide transitions in AAA3 gate the transmission of conformational changes between AAA1 and the linker, suggesting that AAA3 acts as a regulatory switch. Further structural and mutational studies also uncover a role for the linker in regulating the catalytic cycle of AAA1. Together, these results reveal how dynein's two major ATP-binding sites initiate and modulate conformational changes in the motor domain during motility.


Assuntos
Trifosfato de Adenosina/análogos & derivados , Dineínas/química , Dineínas/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/química , Trifosfato de Adenosina/metabolismo , Regulação Alostérica , Catálise , Cristalografia por Raios X , Dictyostelium/química , Dineínas/ultraestrutura , Microscopia Eletrônica , Modelos Moleculares , Estrutura Terciária de Proteína , Proteínas de Saccharomyces cerevisiae/ultraestrutura
5.
EMBO J ; 43(16): 3388-3413, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38918634

RESUMO

Nuclear exclusion of the RNA- and DNA-binding protein TDP-43 can induce neurodegeneration in different diseases. Diverse processes have been implicated to influence TDP-43 mislocalization, including disrupted nucleocytoplasmic transport (NCT); however, the physiological pathways that normally ensure TDP-43 nuclear localization are unclear. The six-transmembrane enzyme glycerophosphodiester phosphodiesterase 2 (GDE2 or GDPD5) cleaves the glycosylphosphatidylinositol (GPI) anchor that tethers some proteins to the membrane. Here we show that GDE2 maintains TDP-43 nuclear localization by regulating the dynamics of canonical Wnt signaling. Ablation of GDE2 causes aberrantly sustained Wnt activation in adult neurons, which is sufficient to cause NCT deficits, nuclear pore abnormalities, and TDP-43 nuclear exclusion. Disruption of GDE2 coincides with TDP-43 abnormalities in postmortem tissue from patients with amyotrophic lateral sclerosis (ALS). Further, GDE2 deficits are evident in human neural cell models of ALS, which display erroneous Wnt activation that, when inhibited, increases mRNA levels of genes regulated by TDP-43. Our study identifies GDE2 as a critical physiological regulator of Wnt signaling in adult neurons and highlights Wnt pathway activation as an unappreciated mechanism contributing to nucleocytoplasmic transport and TDP-43 abnormalities in disease.


Assuntos
Proteínas de Ligação a DNA , Neurônios , Diester Fosfórico Hidrolases , Via de Sinalização Wnt , Humanos , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/genética , Animais , Neurônios/metabolismo , Camundongos , Diester Fosfórico Hidrolases/metabolismo , Diester Fosfórico Hidrolases/genética , Esclerose Lateral Amiotrófica/metabolismo , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/patologia , Transporte Ativo do Núcleo Celular , Núcleo Celular/metabolismo
6.
Proc Natl Acad Sci U S A ; 121(30): e2405846121, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39012829

RESUMO

High-entropy compounds have been emerging as promising candidates for electrolysis, yet their controllable electrosynthesis strategy remains a formidable challenge because of the ambiguous ionic interaction and codeposition mechanism. Herein, we report a oxygenates directionally induced electrodeposition strategy to construct high-entropy materials with amorphous features, on which the structural evolution from high-entropy phosphide to oxide is confirmed by introducing vanadate, thus realizing the simultaneous optimization of composition and structure. The representative P-CoNiMnWVOx shows excellent bifunctional catalytic performance toward alkaline hydrogen evolution reaction and ethanol oxidation reaction (EOR), with small potentials of -168 mV and 1.38 V at 100 mA cm-2, respectively. In situ spectroscopy illustrates that the electrochemical reconstruction of P-CoNiMnWVOx induces abundant Co-O species as the main catalytic active species for EOR and follows the conversion pathway of the C2 product. Theoretical calculations reveal the optimized electronic structure and adsorption free energy of reaction intermediates on P-CoNiMnWVOx, thereby resulting in a facilitated kinetic process. A membrane-free electrolyzer delivers both high Faradaic efficiencies of acetate and H2 over 95% and superior stability at100 mA cm-2 during 120 h electrolysis. In addition, the unique composition and structural advantages endow P-CoNiMnWVOx with multifunctional catalytic activity and realize multipathway electrosynthesis of formate-coupled hydrogen production.

7.
Proc Natl Acad Sci U S A ; 121(37): e2314337121, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39226363

RESUMO

Epidemiological studies have revealed an inverse relationship between the incidence of Alzheimer's disease (AD) and various cancers, including colorectal cancer (CRC). We aimed to determine whether the incidence of CRC is reduced in AD-like mice and whether gut microbiota confers resistance to tumorigenesis through inducing inflammatory tolerance using 16S ribosomal RNA gene sequencing and fecal microbiota transplantation (FMT). AD-like mice experienced a significantly decreased incidence of CRC tumorigenesis induced by azoxymethane-dextran sodium sulfate as evidenced by suppressed intestinal inflammation compared with control mice. However, FMT from age-matched control mice reversed the inhibitory effects on the tumorigenesis of CRC and inflammatory response in AD-like mice. The key bacterial genera in gut microbiota, including Prevotella, were increased in both the AD-like mice and in patients with amnestic mild cognitive impairment (aMCI) but were decreased in patients with CRC. Pretreatment with low-dose Prevotella-derived lipopolysaccharides (LPS) induced inflammatory tolerance both in vivo and in vitro and inhibited CRC tumorigenesis in mice. Imbalanced gut microbiota increased intestinal barrier permeability, which facilitated LPS absorption from the gut into the blood, causing cognitive decline in AD-like mice and patients with aMCI. These data reveal that intestinal Prevotella-derived LPS exerts a resistant effect to CRC tumorigenesis via inducing inflammatory tolerance in the presence of AD. These findings provide biological evidence demonstrating the inverse relationship between the incidence of AD and CRC.


Assuntos
Doença de Alzheimer , Neoplasias Colorretais , Transplante de Microbiota Fecal , Microbioma Gastrointestinal , Animais , Doença de Alzheimer/microbiologia , Neoplasias Colorretais/microbiologia , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/patologia , Camundongos , Humanos , Masculino , Inflamação , Disfunção Cognitiva , Feminino , Prevotella , Modelos Animais de Doenças , Lipopolissacarídeos , Carcinogênese , Sulfato de Dextrana
8.
Proc Natl Acad Sci U S A ; 121(16): e2400077121, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38598345

RESUMO

Type 2 alveolar epithelial cells (AEC2s) are stem cells in the adult lung that contribute to lower airway repair. Agents that promote the selective expansion of these cells might stimulate regeneration of the compromised alveolar epithelium, an etiology-defining event in several pulmonary diseases. From a high-content imaging screen of the drug repurposing library ReFRAME, we identified that dipeptidyl peptidase 4 (DPP4) inhibitors, widely used type 2 diabetes medications, selectively expand AEC2s and are broadly efficacious in several mouse models of lung damage. Mechanism of action studies revealed that the protease DPP4, in addition to processing incretin hormones, degrades IGF-1 and IL-6, essential regulators of AEC2 expansion whose levels are increased in the luminal compartment of the lung in response to drug treatment. To selectively target DPP4 in the lung with sufficient drug exposure, we developed NZ-97, a locally delivered, lung persistent DPP4 inhibitor that broadly promotes efficacy in mouse lung damage models with minimal peripheral exposure and good tolerability. This work reveals DPP4 as a central regulator of AEC2 expansion and affords a promising therapeutic approach to broadly stimulate regenerative repair in pulmonary disease.


Assuntos
Células Epiteliais Alveolares , Diabetes Mellitus Tipo 2 , Animais , Camundongos , Células Epiteliais Alveolares/metabolismo , Dipeptidil Peptidase 4/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Pulmão/metabolismo , Modelos Animais de Doenças
9.
Hum Mol Genet ; 33(12): 1064-1073, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38507061

RESUMO

Cancer-associated fibroblasts (CAFs) are increasingly recognized as playing a crucial role in regulating cancer progression and metastasis. These cells can be activated by long non-coding RNAs (lncRNAs), promoting the malignant biological processes of tumor cells. Therefore, it is essential to understand the regulatory relationship between CAFs and lncRNAs in cancers. Here, we identified CAF-related lncRNAs at the pan-cancer level to systematically predict their potential regulatory functions. The identified lncRNAs were also validated using various external data at both tissue and cellular levels. This study has revealed that these CAF-related lncRNAs exhibit expression perturbations in cancers and are highly correlated with the infiltration of stromal cells, particularly fibroblasts and endothelial cells. By prioritizing a list of CAF-related lncRNAs, we can further distinguish patient subtypes that show survival and molecular differences. In addition, we have developed a web server, CAFLnc (https://46906u5t63.zicp.fun/CAFLnc/), to visualize our results. In conclusion, CAF-related lncRNAs hold great potential as a valuable resource for comprehending lncRNA functions and advancing the identification of biomarkers for cancer progression and therapeutic targets in cancer treatment.


Assuntos
Fibroblastos Associados a Câncer , Carcinogênese , Regulação Neoplásica da Expressão Gênica , Neoplasias , RNA Longo não Codificante , RNA Longo não Codificante/genética , Humanos , Neoplasias/genética , Neoplasias/patologia , Fibroblastos Associados a Câncer/metabolismo , Fibroblastos Associados a Câncer/patologia , Carcinogênese/genética , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Perfilação da Expressão Gênica , Microambiente Tumoral/genética
10.
Nature ; 577(7790): 350-354, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31942055

RESUMO

Transparent piezoelectrics are highly desirable for numerous hybrid ultrasound-optical devices ranging from photoacoustic imaging transducers to transparent actuators for haptic applications1-7. However, it is challenging to achieve high piezoelectricity and perfect transparency simultaneously because most high-performance piezoelectrics are ferroelectrics that contain high-density light-scattering domain walls. Here, through a combination of phase-field simulations and experiments, we demonstrate a relatively simple method of using an alternating-current electric field to engineer the domain structures of originally opaque rhombohedral Pb(Mg1/3Nb2/3)O3-PbTiO3 (PMN-PT) crystals to simultaneously generate near-perfect transparency, an ultrahigh piezoelectric coefficient d33 (greater than 2,100 picocoulombs per newton), an excellent electromechanical coupling factor k33 (about 94 per cent) and a large electro-optical coefficient γ33 (approximately 220 picometres per volt), which is far beyond the performance of the commonly used transparent ferroelectric crystal LiNbO3. We find that increasing the domain size leads to a higher d33 value for the [001]-oriented rhombohedral PMN-PT crystals, challenging the conventional wisdom that decreasing the domain size always results in higher piezoelectricity8-10. This work presents a paradigm for achieving high transparency and piezoelectricity by ferroelectric domain engineering, and we expect the transparent ferroelectric crystals reported here to provide a route to a wide range of hybrid device applications, such as medical imaging, self-energy-harvesting touch screens and invisible robotic devices.

11.
PLoS Genet ; 19(8): e1010843, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37535699

RESUMO

Rapid depletion of cellular ATP can occur by oxidative stress induced by reactive oxygen species (ROS). Maintaining energy homeostasis requires the key molecular components AMP-activated protein kinase (AMPK) and arginine kinase (AK), an invertebrate orthologue of the mammalian creatine kinase (CK). Here, we deciphered two independent and synergistic pathways of AMPK acting on AK by using the beetle Tribolium castaneum as a model system. First, AMPK acts on transcriptional factor forkhead box O (FOXO) leading to phosphorylation and nuclear translocation of the FOXO. The phospho-FOXO directly promotes the expression of AK upon oxidative stress. Concomitantly, AMPK directly phosphorylates the AK to switch the direction of enzymatic catalysis for rapid production of ATP from the phosphoarginine-arginine pool. Further in vitro assays revealed that Sf9 cells expressing phospho-deficient AK mutants displayed the lower ATP/ADP ratio and cell viability under paraquat-induced oxidative stress conditions when compared with Sf9 cells expressing wild-type AKs. Additionally, the AMPK-FOXO-CK pathway is also involved in the restoration of ATP homeostasis under oxidative stress in mammalian HEK293 cells. Overall, we provide evidence that two distinct AMPK-AK pathways, transcriptional and post-translational regulations, are coherent responders to acute oxidative stresses and distinguished from classical AMPK-mediated long-term metabolic adaptations to energy challenge.


Assuntos
Proteínas Quinases Ativadas por AMP , Arginina Quinase , Animais , Humanos , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Arginina Quinase/metabolismo , Células HEK293 , Estresse Oxidativo/genética , Fosforilação , Homeostase , Trifosfato de Adenosina/genética , Trifosfato de Adenosina/metabolismo , Mamíferos/metabolismo
12.
Proc Natl Acad Sci U S A ; 120(10): e2214038120, 2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-36853946

RESUMO

The association of decreased fecundity with insecticide resistance and the negative sublethal effects of insecticides on insect reproduction indicates the typical trade-off between two highly energy-demanding processes, detoxification and reproduction. However, the underlying mechanisms are poorly understood. The energy sensor adenosine monophosphate-activated protein kinase (AMPK) and the transcription factor Cap "n" collar isoform C (CncC) are important regulators of energy metabolism and xenobiotic response, respectively. In this study, using the beetle Tribolium castaneum as a model organism, we found that deltamethrin-induced oxidative stress activated AMPK, which promoted the nuclear translocation of CncC through its phosphorylation. The CncC not only acts as a transcription activator of cytochrome P450 genes but also regulates the expression of genes coding for ecdysteroid biosynthesis and juvenile hormone (JH) degradation enzymes, resulting in increased ecdysteroid levels as well as decreased JH titer and vitellogenin (Vg) gene expression. These data show that in response to xenobiotic stress, the pleiotropic AMPK-CncC signaling pathway mediates the trade-off between detoxification and reproduction by up-regulating detoxification genes and disturbing hormonal homeostasis.


Assuntos
Proteínas Quinases Ativadas por AMP , Ecdisteroides , Proteínas Quinases Ativadas por AMP/genética , Reprodução , Transdução de Sinais , Xenobióticos , Fatores de Transcrição/metabolismo
13.
Proc Natl Acad Sci U S A ; 120(3): e2215071120, 2023 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-36623192

RESUMO

CAG trinucleotide repeat expansions cause several neurodegenerative diseases, including Huntington's disease and spinocerebellar ataxia. RNAs with expanded CAG repeats contribute to disease in two unusual ways. First, these repeat-containing RNAs may agglomerate in the nucleus as foci that sequester several RNA-binding proteins. Second, these RNAs may undergo aberrant repeat-associated non-AUG (RAN) translation in multiple frames and produce aggregation-prone proteins. The relationship between RAN translation and RNA foci, and their relative contributions to cellular dysfunction, are unclear. Here, we show that CAG repeat-containing RNAs that undergo RAN translation first accumulate at nuclear foci and, over time, are exported to the cytoplasm. In the cytoplasm, these RNAs are initially dispersed but, upon RAN translation, aggregate with the RAN translation products. These RNA-RAN protein agglomerates sequester various RNA-binding proteins and are associated with the disruption of nucleocytoplasmic transport and cell death. In contrast, RNA accumulation at nuclear foci alone does not produce discernable defects in nucleocytoplasmic transport or cell viability. Inhibition of RAN translation prevents cytoplasmic RNA aggregation and alleviates cell toxicity. Our findings demonstrate that RAN translation-induced RNA-protein aggregation correlates with the key pathological hallmarks observed in disease and suggest that cytoplasmic RNA aggregation may be an underappreciated phenomenon in CAG trinucleotide repeat expansion disorders.


Assuntos
Doença de Huntington , Ataxias Espinocerebelares , Humanos , RNA/genética , Expansão das Repetições de Trinucleotídeos/genética , Ataxias Espinocerebelares/genética , Doença de Huntington/genética
14.
J Neurosci ; 44(30)2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-38897723

RESUMO

Light plays an essential role in a variety of physiological processes, including vision, mood, and glucose homeostasis. However, the intricate relationship between light and an animal's feeding behavior has remained elusive. Here, we found that light exposure suppresses food intake, whereas darkness amplifies it in male mice. Interestingly, this phenomenon extends its reach to diurnal male Nile grass rats and healthy humans. We further show that lateral habenula (LHb) neurons in mice respond to light exposure, which in turn activates 5-HT neurons in the dorsal Raphe nucleus (DRN). Activation of the LHb→5-HTDRN circuit in mice blunts darkness-induced hyperphagia, while inhibition of the circuit prevents light-induced anorexia. Together, we discovered a light-responsive neural circuit that relays the environmental light signals to regulate feeding behavior in mice.


Assuntos
Comportamento Alimentar , Habenula , Luz , Animais , Masculino , Camundongos , Habenula/fisiologia , Comportamento Alimentar/fisiologia , Núcleo Dorsal da Rafe/fisiologia , Humanos , Camundongos Endogâmicos C57BL , Ingestão de Alimentos/fisiologia , Vias Neurais/fisiologia , Ratos , Neurônios Serotoninérgicos/fisiologia , Rede Nervosa/fisiologia , Escuridão
15.
Mol Biol Evol ; 41(2)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38225175

RESUMO

Speciation in the face of gene flow is usually associated with a heterogeneous genomic landscape of divergence in nascent species pairs. However, multiple factors, such as divergent selection and local recombination rate variation, can influence the formation of these genomic islands. Examination of the genomic landscapes of species pairs that are still in the early stages of speciation provides an insight into this conundrum. In this study, population genomic analyses were undertaken using a wide range of sampling and whole-genome resequencing data from 96 unrelated individuals of Kentish plover (Charadrius alexandrinus) and white-faced plover (Charadrius dealbatus). We suggest that the two species exhibit varying levels of population admixture along the Chinese coast and on the Taiwan Island. Genome-wide analyses for introgression indicate that ancient introgression had occurred in Taiwan population, and gene flow is still ongoing in mainland coastal populations. Furthermore, we identified a few genomic regions with significant levels of interspecific differentiation and local recombination suppression, which contain several genes potentially associated with disease resistance, coloration, and regulation of plumage molting and thus may be relevant to the phenotypic and ecological divergence of the two nascent species. Overall, our findings suggest that divergent selection in low recombination regions may be a main force in shaping the genomic islands in two incipient shorebird species.


Assuntos
Estudo de Associação Genômica Ampla , Ilhas Genômicas , Humanos , Especiação Genética , Genoma , Fluxo Gênico , Recombinação Genética , Seleção Genética
16.
Front Neuroendocrinol ; 74: 101144, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38797197

RESUMO

Ageing is inherent to all human beings, most mechanistic explanations of ageing results from the combined effects of various physiological and pathological processes. Additionally, aging pivotally contributes to several chronic diseases. Activating transcription factor 4 (ATF4), a member of the ATF/cAMP response element-binding protein family, has recently emerged as a pivotal player owing to its indispensable role in the pathophysiological processes of Alzheimer's disease and aging-related diseases. Moreover, ATF4 is integral to numerous biological processes. Therefore, this article aims to comprehensively review relevant research on the role of ATF4 in the onset and progression of aging-related diseases, elucidating its potential mechanisms and therapeutic approaches. Our objective is to furnish scientific evidence for the early identification of risk factors in aging-related diseases and pave the way for new research directions for their treatment. By elucidating the signaling pathway network of ATF4 in aging-related diseases, we aspire to gain a profound understanding of the molecular and cellular mechanisms, offering novel strategies for addressing aging and developing related therapeutics.


Assuntos
Fator 4 Ativador da Transcrição , Envelhecimento , Doença de Alzheimer , Humanos , Doença de Alzheimer/metabolismo , Doença de Alzheimer/tratamento farmacológico , Fator 4 Ativador da Transcrição/metabolismo , Envelhecimento/metabolismo , Animais , Transdução de Sinais/fisiologia
17.
Hum Mol Genet ; 32(3): 357-366, 2023 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-35771227

RESUMO

DNA drug molecules are not only widely used in gene therapy, but also play an important role in controlling the electrical properties of molecular electronics. Covalent binding, groove binding and intercalation are all important forms of drug-DNA interaction. But its applications are limited due to a lack of understanding of the electron transport mechanisms after different drug-DNA interaction modes. Here, we used a combination of density functional theory calculations and nonequilibrium Green's function formulation with decoherence to study the effect of drug molecules on the charge transport property of DNA under three different binding modes. Conductance of DNA is found to decrease from 2.35E-5 G0 to 1.95E-6 G0 upon doxorubicin intercalation due to modifications of the density of states in the near-highest occupied molecular orbital region, δG = 1105.13%. Additionally, the conductance of DNA after cis-[Pt(NH3)2(py)Cl]+ covalent binding increases from 1.02E-6 G0 to 5.25E-5 G0, δG = 5047.06%. However, in the case of pentamidine groove binding, because there is no direct change in DNA molecular structure during drug binding, the conductance changes before and after drug binding is much smaller than in the two above cases, δG = 90.43%. Our theoretical calculations suggest that the conductance of DNA can be regulated by different drug molecules or switching the interaction modes between small molecules and DNA. This regulation opens new possibilities for their potential applications in controllable modulation of the electron transport property of DNA.


Assuntos
DNA , Transporte de Elétrons
18.
J Cell Sci ; 136(12)2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37288813

RESUMO

The axon initial segment (AIS) is a highly specialized neuronal compartment that regulates the generation of action potentials and maintenance of neuronal polarity. Live imaging of the AIS is challenging due to the limited number of suitable labeling methods. To overcome this limitation, we established a novel approach for live labeling of the AIS using unnatural amino acids (UAAs) and click chemistry. The small size of UAAs and the possibility of introducing them virtually anywhere into target proteins make this method particularly suitable for labeling of complex and spatially restricted proteins. Using this approach, we labeled two large AIS components, the 186 kDa isoform of neurofascin (NF186; encoded by Nfasc) and the 260 kDa voltage-gated Na+ channel (NaV1.6, encoded by Scn8a) in primary neurons and performed conventional and super-resolution microscopy. We also studied the localization of epilepsy-causing NaV1.6 variants with a loss-of-function effect. Finally, to improve the efficiency of UAA incorporation, we developed adeno-associated viral (AAV) vectors for click labeling in neurons, an achievement that could be transferred to more complex systems such as organotypic slice cultures, organoids, and animal models.


Assuntos
Segmento Inicial do Axônio , Química Click , Animais , Potenciais de Ação/fisiologia , Aminoácidos/metabolismo , Segmento Inicial do Axônio/metabolismo , Neurônios , Camundongos , Ratos
19.
J Virol ; 98(6): e0023524, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38775478

RESUMO

Baculoviruses enter insect midgut epithelial cells via a set of occlusion-derived virion (ODV) envelope proteins called per os infectivity factors (PIFs). P74 of Autographa californica multicapsid nucleopolyhedrovirus (AcMNPV), which was the first identified PIF, is cleaved by an endogenous proteinase embedded within the occlusion body during per os infection, but the target site(s) and function of the cleavage have not yet been ascertained. Here, based on bioinformatics analyses, we report that cleavage was predicted at an arginine and lysine-rich region in the middle of P74. A series of recombinant viruses with site-directed mutants in this region of P74 were generated. R325 or R334 was identified as primary cleavage site. In addition, we showed that P74 is also cleaved by brush border membrane vesicles (BBMV) of the host insect at R325 or R334, instead of R195, R196, and R199, as previously reported. Simultaneous mutations in R195, R196, and R199 lead to instability of P74 during ODV release. Bioassays showed that mutations at both R325 and R334 significantly affected oral infectivity. Taken together, our data show that both R325 and R334 of AcMNPV P74 are the primary cleavage site for both occlusion body endogenous proteinase and BBMV proteinase during ODV release and are critical for oral infection. IMPORTANCE: Cleavage of viral envelope proteins is usually an important trigger for viral entry into host cells. Baculoviruses are insect-specific viruses that infect host insects via the oral route. P74, a per os infectivity factor of baculoviruses, is cleaved during viral entry. However, the function and precise cleavage sites of P74 remain unknown. In this study, we found that R325 or R334 between the N- and C-conserved domains of P74 was the primary cleavage site by proteinase either from the occlusion body or host midgut. The biological significance of cleavage seems to be the release of the potential fusion peptide at the N-terminus of the cleaved C-terminal P74. Our results shed light on the cleavage model of P74 and imply its role in membrane fusion in baculovirus per os infection.


Assuntos
Microvilosidades , Nucleopoliedrovírus , Corpos de Oclusão Virais , Peptídeo Hidrolases , Proteínas do Envelope Viral , Animais , Microvilosidades/enzimologia , Microvilosidades/metabolismo , Nucleopoliedrovírus/genética , Nucleopoliedrovírus/metabolismo , Nucleopoliedrovírus/fisiologia , Corpos de Oclusão Virais/enzimologia , Corpos de Oclusão Virais/metabolismo , Corpos de Oclusão Virais/virologia , Peptídeo Hidrolases/metabolismo , Peptídeo Hidrolases/genética , Células Sf9 , Spodoptera/citologia , Spodoptera/virologia , Proteínas do Envelope Viral/química , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/metabolismo , Vírion/química , Vírion/genética , Vírion/metabolismo , Internalização do Vírus , Mutação , Boca/virologia , Especificidade por Substrato , Liberação de Vírus
20.
FASEB J ; 38(15): e23848, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39092889

RESUMO

Glucocorticoid use may cause elevated intraocular pressure, leading to the development of glucocorticoid-induced glaucoma (GIG). However, the mechanism of GIG development remains incompletely understood. In this study, we subjected primary human trabecular meshwork cells (TMCs) and mice to dexamethasone treatment to mimic glucocorticoid exposure. The myofibroblast transdifferentiation of TMCs was observed in cellular and mouse models, as well as in human trabecular mesh specimens. This was demonstrated by the cytoskeletal reorganization, alterations in cell morphology, heightened transdifferentiation markers, increased extracellular matrix deposition, and cellular dysfunction. Knockdown of Rho guanine nucleotide exchange factor 26 (ARHGEF26) expression ameliorated dexamethasone-induced changes in cell morphology and upregulation of myofibroblast markers, reversed dysfunction and extracellular matrix deposition in TMCs, and prevented the development of dexamethasone-induced intraocular hypertension. And, this process may be related to the TGF-ß pathway. In conclusion, glucocorticoids induced the myofibroblast transdifferentiation in TMCs, which played a crucial role in the pathogenesis of GIG. Inhibition of ARHGEF26 expression protected TMCs by reversing myofibroblast transdifferentiation. This study demonstrated the potential of reversing the myofibroblast transdifferentiation of TMCs as a new target for treating GIG.


Assuntos
Transdiferenciação Celular , Dexametasona , Glaucoma , Miofibroblastos , Fatores de Troca de Nucleotídeo Guanina Rho , Malha Trabecular , Dexametasona/farmacologia , Malha Trabecular/efeitos dos fármacos , Malha Trabecular/metabolismo , Malha Trabecular/citologia , Transdiferenciação Celular/efeitos dos fármacos , Animais , Humanos , Miofibroblastos/efeitos dos fármacos , Miofibroblastos/metabolismo , Miofibroblastos/citologia , Camundongos , Fatores de Troca de Nucleotídeo Guanina Rho/metabolismo , Fatores de Troca de Nucleotídeo Guanina Rho/genética , Glaucoma/patologia , Glaucoma/metabolismo , Células Cultivadas , Glucocorticoides/farmacologia , Camundongos Endogâmicos C57BL , Masculino
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