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1.
Cell ; 174(3): 564-575.e18, 2018 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-30033362

RESUMO

The prostate cancer (PCa) risk-associated SNP rs11672691 is positively associated with aggressive disease at diagnosis. We showed that rs11672691 maps to the promoter of a short isoform of long noncoding RNA PCAT19 (PCAT19-short), which is in the third intron of the long isoform (PCAT19-long). The risk variant is associated with decreased and increased levels of PCAT19-short and PCAT19-long, respectively. Mechanistically, the risk SNP region is bifunctional with both promoter and enhancer activity. The risk variants of rs11672691 and its LD SNP rs887391 decrease binding of transcription factors NKX3.1 and YY1 to the promoter of PCAT19-short, resulting in weaker promoter but stronger enhancer activity that subsequently activates PCAT19-long. PCAT19-long interacts with HNRNPAB to activate a subset of cell-cycle genes associated with PCa progression, thereby promoting PCa tumor growth and metastasis. Taken together, these findings reveal a risk SNP-mediated promoter-enhancer switching mechanism underlying both initiation and progression of aggressive PCa.


Assuntos
Neoplasias da Próstata/genética , RNA Longo não Codificante/genética , Alelos , Linhagem Celular Tumoral , Elementos Facilitadores Genéticos/genética , Regulação Neoplásica da Expressão Gênica/genética , Frequência do Gene/genética , Predisposição Genética para Doença/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Masculino , Polimorfismo de Nucleotídeo Único/genética , Regiões Promotoras Genéticas/genética , Ligação Proteica , Isoformas de RNA/genética , Fatores de Risco , Fatores de Transcrição/metabolismo , Fator de Transcrição YY1/metabolismo
2.
Cell ; 167(3): 739-749.e11, 2016 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-27720449

RESUMO

G protein-coupled receptor (GPCR) signaling, mediated by hetero-trimeric G proteins, can be differentially controlled by agonists. At a molecular level, this is thought to occur principally via stabilization of distinct receptor conformations by individual ligands. These distinct conformations control subsequent recruitment of transducer and effector proteins. Here, we report that ligand efficacy at the calcitonin GPCR (CTR) is also correlated with ligand-dependent alterations to G protein conformation. We observe ligand-dependent differences in the sensitivity of the G protein ternary complex to disruption by GTP, due to conformational differences in the receptor-bound G protein hetero-trimer. This results in divergent agonist-dependent receptor-residency times for the hetero-trimeric G protein and different accumulation rates for downstream second messengers. This study demonstrates that factors influencing efficacy extend beyond receptor conformation(s) and expands understanding of the molecular basis for how G proteins control/influence efficacy. This has important implications for the mechanisms that underlie ligand-mediated biased agonism. VIDEO ABSTRACT.


Assuntos
Proteínas de Ligação ao GTP/química , Guanosina Trifosfato/farmacologia , Receptores da Calcitonina/agonistas , Receptores da Calcitonina/química , Difosfato de Adenosina/biossíntese , Animais , Células COS , Chlorocebus aethiops , Proteínas de Ligação ao GTP/metabolismo , Guanosina Trifosfato/metabolismo , Humanos , Ligantes , Conformação Proteica , Multimerização Proteica , Receptores da Calcitonina/metabolismo
3.
Nature ; 618(7967): 981-985, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37225998

RESUMO

Soils store more carbon than other terrestrial ecosystems1,2. How soil organic carbon (SOC) forms and persists remains uncertain1,3, which makes it challenging to understand how it will respond to climatic change3,4. It has been suggested that soil microorganisms play an important role in SOC formation, preservation and loss5-7. Although microorganisms affect the accumulation and loss of soil organic matter through many pathways4,6,8-11, microbial carbon use efficiency (CUE) is an integrative metric that can capture the balance of these processes12,13. Although CUE has the potential to act as a predictor of variation in SOC storage, the role of CUE in SOC persistence remains unresolved7,14,15. Here we examine the relationship between CUE and the preservation of SOC, and interactions with climate, vegetation and edaphic properties, using a combination of global-scale datasets, a microbial-process explicit model, data assimilation, deep learning and meta-analysis. We find that CUE is at least four times as important as other evaluated factors, such as carbon input, decomposition or vertical transport, in determining SOC storage and its spatial variation across the globe. In addition, CUE shows a positive correlation with SOC content. Our findings point to microbial CUE as a major determinant of global SOC storage. Understanding the microbial processes underlying CUE and their environmental dependence may help the prediction of SOC feedback to a changing climate.


Assuntos
Sequestro de Carbono , Carbono , Ecossistema , Microbiologia do Solo , Solo , Carbono/análise , Carbono/metabolismo , Mudança Climática , Plantas , Solo/química , Conjuntos de Dados como Assunto , Aprendizado Profundo
4.
Mol Cell ; 77(3): 656-668.e5, 2020 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-32004469

RESUMO

Class B G protein-coupled receptors (GPCRs) are important therapeutic targets for major diseases. Here, we present structures of peptide and Gs-bound pituitary adenylate cyclase-activating peptide, PAC1 receptor, and corticotropin-releasing factor (CRF), (CRF1) receptor. Together with recently solved structures, these provide coverage of the major class B GPCR subfamilies. Diverse orientations of the extracellular domain to the receptor core in different receptors are at least partially dependent on evolutionary conservation in the structure and nature of peptide interactions. Differences in peptide interactions to the receptor core also influence the interlinked TM2-TM1-TM6/ECL3/TM7 domain, and this is likely important in their diverse signaling. However, common conformational reorganization of ECL2, linked to reorganization of ICL2, modulates G protein contacts. Comparison between receptors reveals ICL2 as a key domain forming dynamic G protein interactions in a receptor- and ligand-specific manner. This work advances our understanding of class B GPCR activation and Gs coupling.


Assuntos
Receptores de Hormônio Liberador da Corticotropina/ultraestrutura , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/ultraestrutura , Sequência de Aminoácidos , Microscopia Crioeletrônica/métodos , Encefalinas , Humanos , Ligantes , Modelos Moleculares , Peptídeos , Precursores de Proteínas , Receptores de Hormônio Liberador da Corticotropina/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Receptores Acoplados a Proteínas G/ultraestrutura , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/metabolismo , Transdução de Sinais
5.
Mol Cell ; 80(3): 485-500.e7, 2020 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-33027691

RESUMO

Peptide drugs targeting class B1 G-protein-coupled receptors (GPCRs) can treat multiple diseases; however, there remains substantial interest in the development of orally delivered non-peptide drugs. Here, we reveal unexpected overlap between signaling and regulation of the glucagon-like peptide-1 (GLP-1) receptor by the non-peptide agonist PF 06882961 and GLP-1 that was not observed for another compound, CHU-128. Compounds from these patent series, including PF 06882961, are currently in clinical trials for treatment of type 2 diabetes. High-resolution cryoelectron microscopy (cryo-EM) structures reveal that the binding sites for PF 06882961 and GLP-1 substantially overlap, whereas CHU-128 adopts a unique binding mode with a more open receptor conformation at the extracellular face. Structural differences involving extensive water-mediated hydrogen bond networks could be correlated to functional data to understand how PF 06882961, but not CHU-128, can closely mimic the pharmacological properties of GLP-1. These findings will facilitate rational structure-based discovery of non-peptide agonists targeting class B GPCRs.


Assuntos
Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Animais , Sítios de Ligação/fisiologia , Microscopia Crioeletrônica/métodos , Peptídeo 1 Semelhante ao Glucagon/química , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Receptor do Peptídeo Semelhante ao Glucagon 1/química , Humanos , Peptídeos/química , Receptores Acoplados a Proteínas G/agonistas , Receptores Acoplados a Proteínas G/química , Receptores Acoplados a Proteínas G/metabolismo , Relação Estrutura-Atividade
6.
Proc Natl Acad Sci U S A ; 121(30): e2408160121, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39024114

RESUMO

As the primary cause for chronic pain and disability in elderly individuals, osteoarthritis (OA) is one of the fastest-growing diseases due to the aging world population. To date, the impact of microenvironmental changes on the pathogenesis of OA remains poorly understood, greatly hindering the development of effective therapeutic approaches against OA. In this study, we profiled the differential metabolites in the synovial fluid from OA patients and identified the downregulation of vitamin B1 (VB1) as a metabolic feature in the OA microenvironment. In a murine destabilization of medial meniscus-induced OA model, supplementation of VB1 significantly mitigated the symptoms of OA. Cytokine array analysis revealed that VB1 treatment remarkably reduced the production of a pro-OA factor-C-C Motif Chemokine Ligand 2 (CCL2), in macrophages. Further evidence demonstrated that exogenous CCL2 counteracted the anti-OA function of VB1. Hence, our study unveils a unique biological function of VB1 and provides promising clues for the diet-based treatment of OA.


Assuntos
Quimiocina CCL2 , Suplementos Nutricionais , Osteoartrite , Tiamina , Animais , Osteoartrite/metabolismo , Osteoartrite/prevenção & controle , Osteoartrite/patologia , Osteoartrite/tratamento farmacológico , Camundongos , Humanos , Quimiocina CCL2/metabolismo , Masculino , Tiamina/metabolismo , Tiamina/administração & dosagem , Tiamina/farmacologia , Feminino , Líquido Sinovial/metabolismo , Modelos Animais de Doenças , Macrófagos/metabolismo , Idoso , Pessoa de Meia-Idade , Camundongos Endogâmicos C57BL
7.
Nature ; 577(7790): 432-436, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31915381

RESUMO

Class B G-protein-coupled receptors are major targets for the treatment of chronic diseases, including diabetes and obesity1. Structures of active receptors reveal peptide agonists engage deep within the receptor core, leading to an outward movement of extracellular loop 3 and the tops of transmembrane helices 6 and 7, an inward movement of transmembrane helix 1, reorganization of extracellular loop 2 and outward movement of the intracellular side of transmembrane helix 6, resulting in G-protein interaction and activation2-6. Here we solved the structure of a non-peptide agonist, TT-OAD2, bound to the glucagon-like peptide-1 (GLP-1) receptor. Our structure identified an unpredicted non-peptide agonist-binding pocket in which reorganization of extracellular loop 3 and transmembrane helices 6 and 7 manifests independently of direct ligand interaction within the deep transmembrane domain pocket. TT-OAD2 exhibits biased agonism, and kinetics of G-protein activation and signalling that are distinct from peptide agonists. Within the structure, TT-OAD2 protrudes beyond the receptor core to interact with the lipid or detergent, providing an explanation for the distinct activation kinetics that may contribute to the clinical efficacy of this compound series. This work alters our understanding of the events that drive the activation of class B receptors.


Assuntos
Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Isoquinolinas/farmacologia , Fenilalanina/análogos & derivados , Piridinas/farmacologia , Animais , Células CHO , Cricetinae , Cricetulus , Receptor do Peptídeo Semelhante ao Glucagon 1/química , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Humanos , Isoquinolinas/química , Cinética , Modelos Moleculares , Fenilalanina/química , Fenilalanina/farmacologia , Estrutura Quaternária de Proteína , Estrutura Terciária de Proteína , Piridinas/química , Homologia Estrutural de Proteína
8.
J Biol Chem ; 300(7): 107474, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38879011

RESUMO

Hearing, the ability to sense sounds, and the processing of auditory information are important for perception of the world. Mice lacking expression of neuroplastin (Np), a type-1 transmembrane glycoprotein, display deafness, multiple cognitive deficiencies, and reduced expression of plasma membrane calcium (Ca2+) ATPases (PMCAs) in cochlear hair cells and brain neurons. In this study, we transferred the deafness causing missense mutations pitch (C315S) and audio-1 (I122N) into human Np (hNp) constructs and investigated their effects at the molecular and cellular levels. Computational molecular dynamics show that loss of the disulfide bridge in hNppitch causes structural destabilization of immunoglobulin-like domain (Ig) III and that the novel asparagine in hNpaudio-1 results in steric constraints and an additional N-glycosylation site in IgII. Additional N-glycosylation of hNpaudio-1 was confirmed by PNGaseF treatment. In comparison to hNpWT, transfection of hNppitch and hNpaudio-1 into HEK293T cells resulted in normal mRNA levels but reduced the Np protein levels and their cell surface expression due to proteasomal/lysosomal degradation. Furthermore, hNppitch and hNpaudio-1 failed to promote exogenous PMCA levels in HEK293T cells. In hippocampal neurons, expression of additional hNppitch or hNpaudio-1 was less efficient than hNpWT to elevate endogenous PMCA levels and to accelerate the restoration of basal Ca2+ levels after electrically evoked Ca2+ transients. We propose that mutations leading to pathological Np variants, as exemplified here by the deafness causing Np mutants, can affect Np-dependent Ca2+ regulatory mechanisms and may potentially cause intellectual and cognitive deficits in humans.

10.
Cereb Cortex ; 34(1)2024 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-38061696

RESUMO

Working memory, which is foundational to higher cognitive function, is the "sketchpad of volitional control." Successful working memory is the inevitable outcome of the individual's active control and manipulation of thoughts and turning them into internal goals during which the causal brain processes information in real time. However, little is known about the dynamic causality among distributed brain regions behind thought control that underpins successful working memory. In our present study, given that correct responses and incorrect ones did not differ in either contralateral delay activity or alpha suppression, further rooting on the high-temporal-resolution EEG time-varying directed network analysis, we revealed that successful working memory depended on both much stronger top-down connections from the frontal to the temporal lobe and bottom-up linkages from the occipital to the temporal lobe, during the early maintenance period, as well as top-down flows from the frontal lobe to the central areas as the delay behavior approached. Additionally, the correlation between behavioral performance and casual interactions increased over time, especially as memory-guided delayed behavior approached. Notably, when using the network metrics as features, time-resolved multiple linear regression of overall behavioral accuracy was exactly achieved as delayed behavior approached. These results indicate that accurate memory depends on dynamic switching of causal network connections and shifting to more task-related patterns during which the appropriate intervention may help enhance memory.


Assuntos
Encéfalo , Memória de Curto Prazo , Memória de Curto Prazo/fisiologia , Encéfalo/fisiologia , Lobo Temporal/fisiologia , Lobo Frontal/fisiologia , Mapeamento Encefálico
11.
J Biol Chem ; 299(11): 105329, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37805139

RESUMO

Prion diseases are a group of transmissible neurodegenerative diseases primarily caused by the conformational conversion of prion protein (PrP) from α-helix-dominant cellular prion protein (PrPC) to ß-sheet-rich pathological aggregated form of PrPSc in many mammalian species. Dogs exhibit resistance to prion diseases, but the mechanism behind the phenomenon remains poorly understood. Compared with human PrP and mouse PrP, dog PrP has two unique amino acid residues, Arg177 and Asp159. Because PrPC contains a low-complexity and intrinsically disordered region in its N-terminal domain, it undergoes liquid-liquid phase separation (LLPS) in vitro and forms protein condensates. However, little is known about whether these two unique residues modulate the formation of PrPC condensates. Here, using confocal microscopy, fluorescence recovery after photobleaching assays, thioflavin T binding assays, and transmission electron microscopy, we report that Arg177 and Asp159 from the dog PrP slow the LLPS of full-length human PrPC, shifting the equilibrium phase boundary to higher protein concentrations and inhibit amyloid formation of the human protein. In sharp contrast, His177 and Asn159 from the human PrP enhance the LLPS of full-length dog PrPC, shifting the equilibrium phase boundary to lower protein concentrations, and promote fibril formation of the canid protein. Collectively, these results demonstrate how LLPS and amyloid formation of PrP are inhibited by a single residue Arg177 or Asp159 associated with prion disease resistance, and how LLPS and fibril formation of PrP are promoted by a single residue His177 or Asn159. Therefore, Arg177/His177 and Asp159/Asn159 are key residues in modulating PrPC liquid-phase condensation.


Assuntos
Doenças Priônicas , Príons , Camundongos , Cães , Humanos , Animais , Proteínas Priônicas/metabolismo , Príons/metabolismo , Amiloide/química , Proteínas Amiloidogênicas , Mamíferos/metabolismo
12.
Immunology ; 172(3): 486-499, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38547355

RESUMO

To explore the effect of K33 only mutant ubiquitin (K33O) on bone marrow-derived dendritic cells' (BMDCs') maturity, antigen uptake capability, surface molecule expressions and BMDC-mediated CTL priming, and further investigate the role of PI3K-Akt engaged in K33O-increased BMDC maturation, antigen uptake and presentation, surface molecule expressions and BMDC-based CTL priming. BMDCs were conferred K33O and other ubiquitin mutants (K33R, K48R, K63R-mutant ubiquitin) incubation or LY294002 and wortmannin pretreatment. PI3K-Akt phosphorylation, antigen uptake, antigenic presentation and CD86/MHC class I expression in BMDC were determined by western blot or flow cytometry. BMDC-based CTL proliferation and priming were determined by in vitro mixed lymphocyte reaction (MLR), ex vivo enzyme-linked immunospot assay (Elispot) and flow cytometry with intracellular staining, respectively. The treatment with K33O effectively augmented PI3K-Akt phosphorylation, BMDCs' antigen uptake, antigenic presentation, CD86/MHC class I and CD11c expressions. MLR, Elispot and flow cytometry revealed that K33O treatment obviously enhanced CTL proliferation, CTL priming and perforin/granzyme B expression. The pretreatment with PI3K-Akt inhibitors efficiently abrogated K33O's effects on BMDC. The replenishment of K33 only mutant ubiquitin augments BMDC-mediated CTL priming in bone marrow-derived dendritic cells via PI3K-Akt signalling.


Assuntos
Apresentação de Antígeno , Células da Medula Óssea , Células Dendríticas , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Transdução de Sinais , Linfócitos T Citotóxicos , Ubiquitina , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Animais , Camundongos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ubiquitina/metabolismo , Linfócitos T Citotóxicos/imunologia , Células da Medula Óssea/imunologia , Células da Medula Óssea/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Apresentação de Antígeno/imunologia , Camundongos Endogâmicos C57BL , Fosforilação , Ativação Linfocitária , Diferenciação Celular , Mutação , Morfolinas/farmacologia , Teste de Cultura Mista de Linfócitos , Proliferação de Células , Antígeno B7-2/metabolismo , Antígeno B7-2/genética , Antígeno B7-2/imunologia , Células Cultivadas , Cromonas/farmacologia , Wortmanina/farmacologia , Androstadienos/farmacologia
13.
Immunology ; 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38829009

RESUMO

Overexpression of T-cell immunoglobulin and mucin-domain containing-3 (TIM-3) on T cells has been observed in smokers. However, whether and how galectin-9 (Gal-9)/TIM-3 signal between T-regulatory cells (Tregs) and type 17 helper (Th17) cells contributes to tobacco smoke-induced airway inflammation remains unclear. Here, we aimed to explore the role of the Gal-9/TIM-3 signal between Tregs and Th17 cells during chronic tobacco smoke exposure. Tregs phenotype and the expression of TIM-3 on CD4+ T cells were detected in a mouse model of experimental emphysema. The role of TIM-3 in CD4+ T cells was explored in a HAVCR2-/- mouse model and in mice that received recombinant anti-TIM3. The crosstalk between Gal-9 and Tim-3 was evaluated by coculture Tregs with effector CD4+ T cells. We also invested the expression of Gal-9 in Tregs in patients with COPD. Our study revealed that chronic tobacco smoke exposure significantly reduces the frequency of Tregs in the lungs of mice and remarkably shapes the heterogeneity of Tregs by downregulating the expression of Gal-9. We observed a pro-inflammatory but restrained phenotypic transition of CD4+ T cells after tobacco smoke exposure, which was maintained by TIM-3. The restrained phenotype of CD4+ T cells was perturbed when TIM-3 was deleted or neutralised. Tregs from the lungs of mice with emphysema displayed a blunt ability to inhibit the differentiation and proliferation of Th17 cells. The inhibitory function of Tregs was partially restored by using recombinant Gal-9. The interaction between Gal-9 and TIM-3 inhibits the differentiation of Th17 cells and promotes apoptosis of CD4+ T cells, possibly by interfering with the expression of retinoic acid receptor-related orphan receptor gamma t. The expression of Gal-9 in Tregs was reduced in patients with COPD, which was associated with Th17 response and lung function. These findings present a new paradigm that impairment of Gal-9/Tim-3 crosstalk between Tregs and Th17 cells during chronic tobacco smoke exposure promotes tobacco smoke-induced airway/lung inflammation.

14.
Biochem Biophys Res Commun ; 703: 149653, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38364682

RESUMO

Cellular vesicle long-distance transport along the cytoplasmic actin network has recently been uncovered in several cell systems. In metaphase mouse oocytes, the motor protein myosin-5b (Myo5b) and the actin nucleation factor Spire are recruited to the Rab11a-positive vesicle membrane, forming a ternary complex of Myo5b/Spire/Rab11a that drives the vesicle long-distance transport to the oocyte cortex. However, the mechanism underlying the intermolecular regulation of the Myo5b/Spire/Rab11a complex remains unknown. In this study, we expressed and purified Myo5b, Spire2, and Rab11a proteins, and performed ATPase activity measurements, pulldown and single-molecule motility assays. Our results demonstrate that both Spire2 and Rab11a are required to activate Myo5b motor activity under physiological ionic conditions. The GTBM fragment of Spire2 stimulates the ATPase activity of Myo5b, while Rab11a enhances this activation. This activation occurs by disrupting the head-tail interaction of Myo5b. Furthermore, at the single-molecule level, we observed that the GTBM fragment of Spire2 and Rab11a coordinate to stimulate the Myo5b motility activity. Based on our results, we propose that upon association with the vesicle membrane, Myo5b, Spire2 and Rab11a form a ternary complex, and the inhibited Myo5b is synergistically activated by Spire2 and Rab11a, thereby triggering the long-distance transport of vesicles.


Assuntos
Actinas , Miosina Tipo V , Camundongos , Animais , Actinas/metabolismo , Miosinas/metabolismo , Citoesqueleto de Actina/metabolismo , Miosina Tipo V/metabolismo , Proteínas rab de Ligação ao GTP/metabolismo
15.
J Virol ; 97(4): e0021023, 2023 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-36975780

RESUMO

Porcine enteric alphacoronavirus (PEAV) is a new bat HKU2-like porcine coronavirus, and its endemic outbreak has caused severe economic losses to the pig industry. Its broad cellular tropism suggests a potential risk of cross-species transmission. A limited understanding of PEAV entry mechanisms may hinder a rapid response to potential outbreaks. This study analyzed PEAV entry events using chemical inhibitors, RNA interference, and dominant-negative mutants. PEAV entry into Vero cells depended on three endocytic pathways: caveolae, clathrin, and macropinocytosis. Endocytosis requires dynamin, cholesterol, and a low pH. Rab5, Rab7, and Rab9 GTPases (but not Rab11) regulate PEAV endocytosis. PEAV particles colocalize with EEA1, Rab5, Rab7, Rab9, and Lamp-1, suggesting that PEAV translocates into early endosomes after internalization, and Rab5, Rab7, and Rab9 regulate trafficking to lysosomes before viral genome release. PEAV enters porcine intestinal cells (IPI-2I) through the same endocytic pathway, suggesting that PEAV may enter various cells through multiple endocytic pathways. This study provides new insights into the PEAV life cycle. IMPORTANCE Emerging and reemerging coronaviruses cause severe human and animal epidemics worldwide. PEAV is the first bat-like coronavirus to cause infection in domestic animals. However, the PEAV entry mechanism into host cells remains unknown. This study demonstrates that PEAV enters into Vero or IPI-2I cells through caveola/clathrin-mediated endocytosis and macropinocytosis, which does not require a specific receptor. Subsequently, Rab5, Rab7, and Rab9 regulate PEAV trafficking from early endosomes to lysosomes, which is pH dependent. The results advance our understanding of the disease and help to develop potential new drug targets against PEAV.


Assuntos
Alphacoronavirus , Cavéolas , Clatrina , Pinocitose , Internalização do Vírus , Proteínas rab de Ligação ao GTP , Alphacoronavirus/fisiologia , Proteínas rab de Ligação ao GTP/metabolismo , Endossomos/metabolismo , Infecções por Coronavirus/metabolismo , Concentração de Íons de Hidrogênio , Dinaminas/metabolismo , Cavéolas/metabolismo , Colesterol/metabolismo , Clatrina/metabolismo , Pinocitose/fisiologia , Células Vero , Chlorocebus aethiops , Animais
16.
J Hum Genet ; 69(1): 33-39, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37853116

RESUMO

Duane retraction syndrome (DRS) is a rare congenital eye movement disorder causing by the dysplasia of abducens nerve, and has highly variable phenotype. MRI can reveal the endophenotype of DRS. Most DRS cases are sporadical and isolated, while some are familial or accompanied by other ocular disorders and systemic congenital abnormalities. CHN1 was the most common causative gene for familial DRS. Until now, 13 missense variants of CHN1 have been reported. In this study, we enrolled two unrelated pedigrees with DRS. Detailed clinical examinations, MRI, and the whole exome sequencing (WES) were performed to reveal their clinical and genetic characteristics. Patients from pedigree-1 presented with isolated DRS, and a novel heterozygous variant c.650 A > G, p. His217Arg was identified in CHN1 gene. Patients from pedigree-2 presented with classic DRS and abnormalities in auricle morphology, and the pedigree segregated another novel heterozygous CHN1 variant c.637 T > C, p. Phe213Leu. A variety of bioinformatics software predicted that the two variants had deleterious or disease-causing effects. After injecting of two mutant CHN1 mRNAs into zebrafish embryos, the dysplasia of ocular motor nerves (OMN) was observed. Our present findings expanded the phenotypic and genotypic spectrum of CHN1 related DRS, as well as provided new insights into the role of CHN1 in OMN development. Genetic testing is strongly recommended for patients with a DRS family history or accompanying systemic congenital abnormalities.


Assuntos
Síndrome da Retração Ocular , Anormalidades do Olho , Animais , Humanos , Síndrome da Retração Ocular/genética , Peixe-Zebra/genética , Linhagem , Mutação de Sentido Incorreto
17.
Opt Lett ; 49(10): 2553-2556, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38748103

RESUMO

Plenty of exotic phenomena in moiré superlattices arise from the emergence of flatbands, but their significance could be diminished by structural disorders that will significantly alter flatbands. Thus, unveiling the effects of disorder on moiré flatbands is crucial. In this work, we explore the disorder effects on two sets of flatbands in silicon-based mismatched moiré superlattices, where the level of disorder is controlled by varying the magnitude of random perturbations of the locations of silicon strips. The results reveal that, after ensemble averaging, the average spectral positions of the four flatbands exhibit stability despite variations in the degree of disorder. However, the δ-like density of states (DOS) related to flatbands in the perfect superlattice evolves into a finite-width envelope of high DOS. By increasing the level of disorder, the width of the DOS envelope increases accordingly. Particularly, we observe a fascinating contrast: the width of bandgap flatbands saturates after initial growth, while the width of dispersive-band-crossed flatbands exhibits a linear increase versus the disorder. This unveils fundamental differences in how flatbands respond to structural imperfections, offering crucial insights into their perturbation characteristics within moiré superlattices. Our work offers new perspectives on flatbands in partially disordered moiré superlattices.

18.
FASEB J ; 37(10): e23206, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37718485

RESUMO

There is a higher expression level of epidermal growth factor receptor (EGFR) in up to 90% of advanced head and neck squamous cell carcinoma (HNSCC) tissue than in normal surrounding tissues. However, the role of RNA-binding proteins (RBPs) in EGFR-associated metastasis of HNSCC remains unclear. In this study, we reveal that RBPs, specifically nucleolin (NCL) and heterogeneous nuclear ribonucleoprotein A2/B1 (hnRNPA2B1), correlated with the mesenchymal phenotype of HNSCC. The depletion of RBPs significantly attenuated EGF-induced HNSCC metastasis. Intriguingly, the EGF-induced EMT markers, such as fibronectin, were regulated by RBPs through the ERK and NF-κB pathway, followed by the enhancement of mRNA stability of fibronectin through the 5' untranslated region (5'-UTR) of the gene. The upregulation of fibronectin triggered the integrin signaling activation to enhance tumor cells' attachment to endothelial cells and increase endothelial permeability. In addition, the concurrence of EGFR and RBPs or EGFR and fibronectin was associated with overall survival and disease-free survival of HNSCC. The in vivo study showed that depletion of NCL, hnRNPA2B1, and fibronectin significantly inhibited EGF-promoted extravasation of tumor cells into lung tissues. The depletion of fibronectin or treatment with integrin inhibitors dramatically attenuated EGF-induced HNSCC metastatic nodules in the lung. Our data suggest that the RBPs/fibronectin axis is essential for EGF-induced tumor-endothelial cell interactions to enhance HNSCC cell metastasis.


Assuntos
Fibronectinas , Neoplasias de Cabeça e Pescoço , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Fibronectinas/genética , Células Endoteliais , Fator de Crescimento Epidérmico , Receptores ErbB/genética , Regiões 5' não Traduzidas , Integrinas , Neoplasias de Cabeça e Pescoço/genética
19.
J Biomed Sci ; 31(1): 10, 2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38243273

RESUMO

BACKGROUND: The tumor microenvironment is characterized by inflammation-like and immunosuppression situations. Although cancer-associated fibroblasts (CAFs) are among the major stromal cell types in various solid cancers, including colon cancer, the interactions between CAFs and immune cells remains largely uncharacterized. Pentraxin 3 (PTX3) is responsive to proinflammatory cytokines and modulates immunity and tissue remodeling, but its involvement in tumor progression appears to be context-dependent and is unclear. METHODS: Open-access databases were utilized to examine the association of PTX3 expression and the fibroblast signature in colon cancer. Loss-of-function assays, including studies in tamoxifen-induced Ptx3 knockout mice and treatment with an anti-PTX3 neutralizing antibody (WHC-001), were conducted to assess the involvement of PTX3 in colon cancer progression as well as its immunosuppressive effect. Finally, bioinformatic analyses and in vitro assays were performed to reveal the downstream effectors and decipher the involvement of the CREB1/CEBPB axis in response to PTX3 and PTX3-induced promotion of M2 macrophage polarization. RESULTS: Clinically, higher PTX3 expression was positively correlated with fibroblasts and inflammatory response signatures and associated with a poor survival outcome in colon cancer patients. Blockade of PTX3 significantly reduced stromal cell-mediated tumor development. The decrease of the M2 macrophage population and an increase of the cytotoxic CD8+ T-cell population were observed following PTX3 inactivation in allografted colon tumors. We further revealed that activation of cyclic AMP-responsive element-binding protein 1 (CREB1) mediated the PTX3-induced promotion of M2 macrophage polarization. CONCLUSIONS: PTX3 contributes to stromal cell-mediated protumor immunity by increasing M2-like macrophage polarization, and inhibition of PTX3 with WHC-001 is a potential therapeutic strategy for colon cancer.


Assuntos
Neoplasias do Colo , Macrófagos , Componente Amiloide P Sérico , Animais , Camundongos , Humanos , Macrófagos/metabolismo , Proteína C-Reativa/genética , Neoplasias do Colo/genética , Terapia de Imunossupressão , Microambiente Tumoral
20.
Crit Rev Food Sci Nutr ; : 1-11, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38356229

RESUMO

Immunoassay based on the antibodies specific for targets has advantages of high sensitivity, simplicity and low cost, therefore it has received more attention in recent years, especially for the rapid detection of small molecule chemicals present in foods, diagnostics and environments. However, limited by low molecular weight and only one antigenic determinant existed, immunoassays for these small molecule chemicals, namely hapten substances, were commonly performed in a competitive immunoassay format, whose sensitivities were obviously lower than the sandwich enzyme-linked immunosorbent assay generally adaptable for the protein targets. In order to break through the bottleneck of detection format, researchers have designed and established several novel noncompetitive immunoassays for the haptens in the past few years. In this review, we focused on the four representative types of noncompetitive immunoassay formats and described their characteristics and applications in rapid detection of small molecules. Meanwhile, a systematic discussion on the current technologies challenges and the possible solutions were also summarized. This review aims to provide an updated overview of the current state-of-the-art in noncompetitive immunoassay for small molecules, and inspire the development of novel designs for small molecule detection.

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