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1.
Cell ; 186(4): 786-802.e28, 2023 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-36754049

RESUMO

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease that results from many diverse genetic causes. Although therapeutics specifically targeting known causal mutations may rescue individual types of ALS, these approaches cannot treat most cases since they have unknown genetic etiology. Thus, there is a pressing need for therapeutic strategies that rescue multiple forms of ALS. Here, we show that pharmacological inhibition of PIKFYVE kinase activates an unconventional protein clearance mechanism involving exocytosis of aggregation-prone proteins. Reducing PIKFYVE activity ameliorates ALS pathology and extends survival of animal models and patient-derived motor neurons representing diverse forms of ALS including C9ORF72, TARDBP, FUS, and sporadic. These findings highlight a potential approach for mitigating ALS pathogenesis that does not require stimulating macroautophagy or the ubiquitin-proteosome system.


Assuntos
Esclerose Lateral Amiotrófica , Fosfatidilinositol 3-Quinases , Animais , Esclerose Lateral Amiotrófica/tratamento farmacológico , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/metabolismo , Neurônios Motores , Mutação , Proteína FUS de Ligação a RNA/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Modelos Animais de Doenças
2.
Cell ; 184(20): 5201-5214.e12, 2021 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-34536345

RESUMO

Certain obligate parasites induce complex and substantial phenotypic changes in their hosts in ways that favor their transmission to other trophic levels. However, the mechanisms underlying these changes remain largely unknown. Here we demonstrate how SAP05 protein effectors from insect-vectored plant pathogenic phytoplasmas take control of several plant developmental processes. These effectors simultaneously prolong the host lifespan and induce witches' broom-like proliferations of leaf and sterile shoots, organs colonized by phytoplasmas and vectors. SAP05 acts by mediating the concurrent degradation of SPL and GATA developmental regulators via a process that relies on hijacking the plant ubiquitin receptor RPN10 independent of substrate ubiquitination. RPN10 is highly conserved among eukaryotes, but SAP05 does not bind insect vector RPN10. A two-amino-acid substitution within plant RPN10 generates a functional variant that is resistant to SAP05 activities. Therefore, one effector protein enables obligate parasitic phytoplasmas to induce a plethora of developmental phenotypes in their hosts.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Arabidopsis/parasitologia , Interações Hospedeiro-Parasita/fisiologia , Parasitos/fisiologia , Proteólise , Ubiquitinas/metabolismo , Sequência de Aminoácidos , Animais , Arabidopsis/genética , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/metabolismo , Engenharia Genética , Humanos , Insetos/fisiologia , Modelos Biológicos , Fenótipo , Fotoperíodo , Filogenia , Phytoplasma/fisiologia , Desenvolvimento Vegetal , Brotos de Planta/crescimento & desenvolvimento , Plantas Geneticamente Modificadas , Complexo de Endopeptidases do Proteassoma/metabolismo , Estabilidade Proteica , Reprodução , Nicotiana , Fatores de Transcrição/metabolismo , Transcrição Gênica
3.
Mol Cell ; 84(3): 490-505.e9, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38128540

RESUMO

SARS-CoV-2 RNA interacts with host factors to suppress interferon responses and simultaneously induces cytokine release to drive the development of severe coronavirus disease 2019 (COVID-19). However, how SARS-CoV-2 hijacks host RNAs to elicit such imbalanced immune responses remains elusive. Here, we analyzed SARS-CoV-2 RNA in situ structures and interactions in infected cells and patient lung samples using RIC-seq. We discovered that SARS-CoV-2 RNA forms 2,095 potential duplexes with the 3' UTRs of 205 host mRNAs to increase their stability by recruiting RNA-binding protein YBX3 in A549 cells. Disrupting the SARS-CoV-2-to-host RNA duplex or knocking down YBX3 decreased host mRNA stability and reduced viral replication. Among SARS-CoV-2-stabilized host targets, NFKBIZ was crucial for promoting cytokine production and reducing interferon responses, probably contributing to cytokine storm induction. Our study uncovers the crucial roles of RNA-RNA interactions in the immunopathogenesis of RNA viruses such as SARS-CoV-2 and provides valuable host targets for drug development.


Assuntos
COVID-19 , Humanos , COVID-19/genética , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , RNA Viral/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Interferons/genética , Citocinas
4.
Immunity ; 53(5): 1108-1122.e5, 2020 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-33128875

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic is a global public health crisis. However, little is known about the pathogenesis and biomarkers of COVID-19. Here, we profiled host responses to COVID-19 by performing plasma proteomics of a cohort of COVID-19 patients, including non-survivors and survivors recovered from mild or severe symptoms, and uncovered numerous COVID-19-associated alterations of plasma proteins. We developed a machine-learning-based pipeline to identify 11 proteins as biomarkers and a set of biomarker combinations, which were validated by an independent cohort and accurately distinguished and predicted COVID-19 outcomes. Some of the biomarkers were further validated by enzyme-linked immunosorbent assay (ELISA) using a larger cohort. These markedly altered proteins, including the biomarkers, mediate pathophysiological pathways, such as immune or inflammatory responses, platelet degranulation and coagulation, and metabolism, that likely contribute to the pathogenesis. Our findings provide valuable knowledge about COVID-19 biomarkers and shed light on the pathogenesis and potential therapeutic targets of COVID-19.


Assuntos
Infecções por Coronavirus/sangue , Infecções por Coronavirus/patologia , Plasma/metabolismo , Pneumonia Viral/sangue , Pneumonia Viral/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Betacoronavirus , Biomarcadores/sangue , Proteínas Sanguíneas/metabolismo , COVID-19 , Infecções por Coronavirus/classificação , Infecções por Coronavirus/metabolismo , Feminino , Humanos , Aprendizado de Máquina , Masculino , Pessoa de Meia-Idade , Pandemias/classificação , Pneumonia Viral/classificação , Pneumonia Viral/metabolismo , Proteômica , Reprodutibilidade dos Testes , SARS-CoV-2
5.
PLoS Biol ; 22(2): e3002518, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38386616

RESUMO

Neurons in the subthalamic nucleus (STN) become hyperactive following nerve injury and promote pain-related responses in mice. Considering that the anterior cingulate cortex (ACC) is involved in pain and emotion processing and projects to the STN, we hypothesize that ACC neurons may contribute to hyperactivity in STN neurons in chronic pain. In the present study, we showed that ACC neurons enhanced activity in response to noxious stimuli and to alterations in emotional states and became hyperactive in chronic pain state established by spared nerve injury of the sciatic nerve (SNI) in mice. In naïve mice, STN neurons were activated by noxious stimuli, but not by alterations in emotional states. Pain responses in STN neurons were attenuated in both naïve and SNI mice when ACC neurons were inhibited. Furthermore, optogenetic activation of the ACC-STN pathway induced bilateral hyperalgesia and depression-like behaviors in naive mice; conversely, inhibition of this pathway is sufficient to attenuate hyperalgesia and depression-like behaviors in SNI mice and naïve mice subjected to stimulation of STN neurons. Finally, mitigation of pain-like and depression-like behaviors in SNI mice by inhibition of the ACC-STN projection was eliminated by activation of STN neurons. Our results demonstrate that hyperactivity in the ACC-STN pathway may be an important pathophysiology in comorbid chronic pain and depression. Thus, the ACC-STN pathway may be an intervention target for the treatment of the comorbid chronic pain and depression.


Assuntos
Dor Crônica , Camundongos , Masculino , Animais , Giro do Cíngulo/fisiologia , Hiperalgesia , Depressão , Neurônios/fisiologia
6.
J Neurosci ; 44(15)2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38453468

RESUMO

The comorbidity of chronic pain and depression poses tremendous challenges for the treatment of either one because they exacerbate each other with unknown mechanisms. As the posterior insular cortex (PIC) integrates multiple somatosensory and emotional information and is implicated in either chronic pain or depression, we hypothesize that the PIC and its projections may contribute to the pathophysiology of comorbid chronic pain and depression. We show that PIC neurons were readily activated by mechanical, thermal, aversive, and stressful and appetitive stimulation in naive and neuropathic pain male mice subjected to spared nerve injury (SNI). Optogenetic activation of PIC neurons induced hyperalgesia and conditioned place aversion in naive mice, whereas inhibition of these neurons led to analgesia, conditioned place preference (CPP), and antidepressant effect in both naive and SNI mice. Combining neuronal tracing, optogenetics, and electrophysiological techniques, we found that the monosynaptic glutamatergic projections from the PIC to the basolateral amygdala (BLA) and the ventromedial nucleus (VM) of the thalamus mimicked PIC neurons in pain modulation in naive mice; in SNI mice, both projections were enhanced accompanied by hyperactivity of PIC, BLA, and VM neurons and inhibition of these projections led to analgesia, CPP, and antidepressant-like effect. The present study suggests that potentiation of the PIC→BLA and PIC→VM projections may be important pathophysiological bases for hyperalgesia and depression-like behavior in neuropathic pain and reversing the potentiation may be a promising therapeutic strategy for comorbid chronic pain and depression.


Assuntos
Dor Crônica , Neuralgia , Camundongos , Masculino , Animais , Hiperalgesia , Dor Crônica/complicações , Depressão , Córtex Insular , Tonsila do Cerebelo/metabolismo , Neuralgia/metabolismo , Comorbidade , Tálamo , Antidepressivos/uso terapêutico
7.
Circulation ; 149(17): 1354-1371, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38314588

RESUMO

BACKGROUND: Pulmonary hypertension (PH) is a progressive cardiopulmonary disease with a high mortality rate. Although growing evidence has revealed the importance of dysregulated energetic metabolism in the pathogenesis of PH, the underlying cellular and molecular mechanisms are not fully understood. In this study, we focused on ME1 (malic enzyme 1), a key enzyme linking glycolysis to the tricarboxylic acid cycle. We aimed to determine the role and mechanistic action of ME1 in PH. METHODS: Global and endothelial-specific ME1 knockout mice were used to investigate the role of ME1 in hypoxia- and SU5416/hypoxia (SuHx)-induced PH. Small hairpin RNA and ME1 enzymatic inhibitor (ME1*) were used to study the mechanism of ME1 in pulmonary artery endothelial cells. Downstream key metabolic pathways and mediators of ME1 were identified by metabolomics analysis in vivo and ME1-mediated energetic alterations were examined by Seahorse metabolic analysis in vitro. The pharmacological effect of ME1* on PH treatment was evaluated in PH animal models induced by SuHx. RESULTS: We found that ME1 protein level and enzymatic activity were highly elevated in lung tissues of patients and mice with PH, primarily in vascular endothelial cells. Global knockout of ME1 protected mice from developing hypoxia- or SuHx-induced PH. Endothelial-specific ME1 deletion similarly attenuated pulmonary vascular remodeling and PH development in mice, suggesting a critical role of endothelial ME1 in PH. Mechanistic studies revealed that ME1 inhibition promoted downstream adenosine production and activated A2AR-mediated adenosine signaling, which leads to an increase in nitric oxide generation and a decrease in proinflammatory molecule expression in endothelial cells. ME1 inhibition activated adenosine production in an ATP-dependent manner through regulating malate-aspartate NADH (nicotinamide adenine dinucleotide plus hydrogen) shuttle and thereby balancing oxidative phosphorylation and glycolysis. Pharmacological inactivation of ME1 attenuated the progression of PH in both preventive and therapeutic settings by promoting adenosine production in vivo. CONCLUSIONS: Our findings indicate that ME1 upregulation in endothelial cells plays a causative role in PH development by negatively regulating adenosine production and subsequently dysregulating endothelial functions. Our findings also suggest that ME1 may represent as a novel pharmacological target for upregulating protective adenosine signaling in PH therapy.

8.
Proc Natl Acad Sci U S A ; 119(26): e2201490119, 2022 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-35733270

RESUMO

Excess bone loss due to increased osteoclastogenesis is a significant clinical problem. Intraflagellar transport (IFT) proteins have been reported to regulate cell growth and differentiation. The role of IFT80, an IFT complex B protein, in osteoclasts (OCs) is completely unknown. Here, we demonstrate that deletion of IFT80 in the myeloid lineage led to increased OC formation and activity accompanied by severe bone loss in mice. IFT80 regulated OC formation by associating with Casitas B-lineage lymphoma proto-oncogene-b (Cbl-b) to promote protein stabilization and proteasomal degradation of tumor necrosis factor (TNF) receptor-associated factor 6 (TRAF6). IFT80 knockdown resulted in increased ubiquitination of Cbl-b and higher TRAF6 levels, thereby hyperactivating the receptor activator of nuclear factor-κß (NF-κß) ligand (RANKL) signaling axis and increased OC formation. Ectopic overexpression of IFT80 rescued osteolysis in a calvarial model of bone loss. We have thus identified a negative function of IFT80 in OCs.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Reabsorção Óssea , Proteínas de Transporte , Osteoclastos , Osteogênese , Proteínas Proto-Oncogênicas c-cbl , Fator 6 Associado a Receptor de TNF , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Reabsorção Óssea/genética , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Diferenciação Celular , Modelos Animais de Doenças , Deleção de Genes , Camundongos , Osteoclastos/citologia , Osteoclastos/metabolismo , Osteogênese/genética , Proteólise , Proteínas Proto-Oncogênicas c-cbl/metabolismo , Ligante RANK/genética , Ligante RANK/metabolismo , Fator 6 Associado a Receptor de TNF/metabolismo , Ubiquitinação
9.
Am J Physiol Renal Physiol ; 327(1): F158-F170, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38779755

RESUMO

Diabetes is closely associated with K+ disturbances during disease progression and treatment. However, it remains unclear whether K+ imbalance occurs in diabetes with normal kidney function. In this study, we examined the effects of dietary K+ intake on systemic K+ balance and renal K+ handling in streptozotocin (STZ)-induced diabetic mice. The control and STZ mice were fed low or high K+ diet for 7 days to investigate the role of dietary K+ intake in renal K+ excretion and K+ homeostasis and to explore the underlying mechanism by evaluating K+ secretion-related transport proteins in distal nephrons. K+-deficient diet caused excessive urinary K+ loss, decreased daily K+ balance, and led to severe hypokalemia in STZ mice compared with control mice. In contrast, STZ mice showed an increased daily K+ balance and elevated plasma K+ level under K+-loading conditions. Dysregulation of the NaCl cotransporter (NCC), epithelial Na+ channel (ENaC), and renal outer medullary K+ channel (ROMK) was observed in diabetic mice fed either low or high K+ diet. Moreover, amiloride treatment reduced urinary K+ excretion and corrected hypokalemia in K+-restricted STZ mice. On the other hand, inhibition of SGLT2 by dapagliflozin promoted urinary K+ excretion and normalized plasma K+ levels in K+-supplemented STZ mice, at least partly by increasing ENaC activity. We conclude that STZ mice exhibited abnormal K+ balance and impaired renal K+ handling under either low or high K+ diet, which could be primarily attributed to the dysfunction of ENaC-dependent renal K+ excretion pathway, despite the possible role of NCC.NEW & NOTEWORTHY Neither low dietary K+ intake nor high dietary K+ intake effectively modulates renal K+ excretion and K+ homeostasis in STZ mice, which is closely related to the abnormality of ENaC expression and activity. SGLT2 inhibitor increases urinary K+ excretion and reduces plasma K+ level in STZ mice under high dietary K+ intake, an effect that may be partly due to the upregulation of ENaC activity.


Assuntos
Diabetes Mellitus Experimental , Canais Epiteliais de Sódio , Potássio na Dieta , Potássio , Animais , Diabetes Mellitus Experimental/metabolismo , Potássio/metabolismo , Potássio/urina , Masculino , Potássio na Dieta/metabolismo , Canais Epiteliais de Sódio/metabolismo , Camundongos Endogâmicos C57BL , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia , Canais de Potássio Corretores do Fluxo de Internalização/metabolismo , Canais de Potássio Corretores do Fluxo de Internalização/genética , Camundongos , Nefropatias Diabéticas/metabolismo , Nefropatias Diabéticas/etiologia , Nefropatias Diabéticas/fisiopatologia , Rim/metabolismo , Rim/efeitos dos fármacos , Rim/fisiopatologia , Hipopotassemia/metabolismo , Amilorida/farmacologia , Eliminação Renal/efeitos dos fármacos , Homeostase , Membro 3 da Família 12 de Carreador de Soluto/metabolismo , Membro 3 da Família 12 de Carreador de Soluto/genética , Glucosídeos/farmacologia , Estreptozocina , Compostos Benzidrílicos , Transportador 2 de Glucose-Sódio
10.
Curr Issues Mol Biol ; 46(3): 1851-1864, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38534737

RESUMO

Autism spectrum disorder (ASD) is thought to result from susceptibility genotypes and environmental risk factors. The offspring of women who experience pregnancy infection have an increased risk for autism. Maternal immune activation (MIA) in pregnant animals produces offspring with autistic behaviors, making MIA a useful model for autism. However, how MIA causes autistic behaviors in offspring is not fully understood. Here, we show that NKCC1 is critical for mediating autistic behaviors in MIA offspring. We confirmed that MIA induced by poly(I:C) infection during pregnancy leads to autistic behaviors in offspring. We further demonstrated that MIA offspring showed significant microglia activation, excessive dendritic spines, and narrow postsynaptic density (PSD) in their prefrontal cortex (PFC). Then, we discovered that these abnormalities may be caused by overexpression of NKCC1 in MIA offspring's PFCs. Finally, we ameliorated the autistic behaviors using PFC microinjection of NKCC1 inhibitor bumetanide (BTN) in MIA offspring. Our findings may shed new light on the pathological mechanisms for autism caused by pregnancy infection.

11.
Br J Cancer ; 130(9): 1517-1528, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38459187

RESUMO

BACKGROUND: Circß-catenin, our first reported circRNA, has been reported to mediate tumorigenesis in various cancers. However, its biological functions and underlying mechanisms in colorectal cancer (CRC) remain unknown. METHODS: The qRT-PCR examination was used to detect the expression of circß-catenin, miR-197-3p, and CTNND1 in cells and human tissues. Western blot was conducted to detect the protein expression levels. The biological function of circß-catenin was verified by MTT, colony formation, wound healing, and transwell assays. The in vivo effects of circß-catenin were verified by nude mice xenograft and metastasis models. The regulatory network of circß-catenin/miR-197-3p/CTNND1 was confirmed via dual-luciferase reporter and RIP assays. RESULTS: In the present study, circß-catenin was found to promote CRC cell proliferation and metastasis in vitro and in vivo. Mechanistically, circß-catenin served as miRNA decoy to directly bind to miR-197-3p, then antagonized the repression of the target gene CTNND1, and eventually promoted the malignant phenotype of CRC. More interestingly, the inverted repeated Alu pairs termed AluJb1/2 and AluY facilitated the biogenesis of circß-catenin, which could be partially reversed by EIF4A3 binding to Alu element AluJb2. CONCLUSIONS: Our findings illustrated a novel mechanism of circß-catenin in modulating CRC tumorigenesis and metastasis, which provides a potential therapeutic target for CRC patients.


Assuntos
Proliferação de Células , Neoplasias Colorretais , Progressão da Doença , Fator de Iniciação 4A em Eucariotos , Camundongos Nus , MicroRNAs , RNA Circular , beta Catenina , MicroRNAs/genética , Humanos , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Neoplasias Colorretais/metabolismo , RNA Circular/genética , Animais , Camundongos , beta Catenina/metabolismo , beta Catenina/genética , Proliferação de Células/genética , Fator de Iniciação 4A em Eucariotos/genética , Fator de Iniciação 4A em Eucariotos/metabolismo , delta Catenina , Regulação Neoplásica da Expressão Gênica , Linhagem Celular Tumoral , Masculino , Feminino , Movimento Celular/genética , Camundongos Endogâmicos BALB C
12.
Apoptosis ; 2024 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-38824479

RESUMO

This study aimed to explore the expression, function, and mechanisms of TBC1D10B in colon cancer, as well as its potential applications in the diagnosis and treatment of the disease.The expression levels of TBC1D10B in colon cancer were assessed by analyzing the TCGA and CCLE databases. Immunohistochemistry analysis was conducted using tumor and adjacent non-tumor tissues from 68 colon cancer patients. Lentiviral infection techniques were employed to silence and overexpress TBC1D10B in colon cancer cells. The effects on cell proliferation, migration, and invasion were evaluated using CCK-8, EDU, wound healing, and Transwell invasion assays. Additionally, GSEA enrichment analysis was used to explore the association of TBC1D10B with biological pathways related to colon cancer. TBC1D10B was significantly upregulated in colon cancer and closely associated with patient prognosis. Silencing of TBC1D10B notably inhibited proliferation, migration, and invasion of colon cancer cells and promoted apoptosis. Conversely, overexpression of TBC1D10B enhanced these cellular functions. GSEA analysis revealed that TBC1D10B is enriched in the AKT/PI3K/mTOR signaling pathway and highly correlated with PAK4. The high expression of TBC1D10B in colon cancer is associated with poor prognosis. It influences cancer progression by regulating the proliferation, migration, and invasion capabilities of colon cancer cells, potentially acting through the AKT/PI3K/mTOR signaling pathway. These findings provide new targets and therapeutic strategies for the treatment of colon cancer.

13.
Anal Chem ; 96(8): 3561-3568, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38372135

RESUMO

Covalent organic frameworks (COFs) are attractive adsorbents for sample pretreatment due to their unique structure and properties. However, the selectivity of COFs for the extraction of hazardous compounds is still limited due to the lack of specific interactions between COFs and targets. Herein, we report a pore size adjustment strategy for room-temperature synthesis of molecularly imprinted COF (MICOF) for selective extraction of zearalenone (ZEN) in complex food samples. The three-dimensional building block tetra(4-aminophenyl) methane was used as a functional monomer, while dialdehyde monomers with different numbers of benzene ring were used to adjust the pore size of MICOF to match with the size of ZEN molecules. The prepared MICOF gave the largest adsorption capacity of 177.2 mg g-1 and the highest imprinting factor of 10.1 for ZEN so far. MICOF was used as the adsorbent for dispersed solid-phase extraction in combination with high-performance liquid chromatography for the determination of trace ZEN in cereals. The high selectivity of the developed method allows simple aqueous standard calibration for the matrix effect-free determination of ZEN in food samples. The limit of detection and the recoveries of the developed method were 0.21 µg kg-1 and 93.7-101.4%, respectively. The precision for the determination of ZEN was less than 3.8% (RSD, n = 6). The developed method is promising for the selective determination of ZEN in complex matrices.


Assuntos
Estruturas Metalorgânicas , Nanosferas , Zearalenona , Estruturas Metalorgânicas/química , Zearalenona/análise , Grão Comestível/química , Temperatura , Cromatografia Líquida de Alta Pressão/métodos , Extração em Fase Sólida/métodos , Adsorção
14.
Appl Environ Microbiol ; 90(3): e0224223, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38358247

RESUMO

The extensive accumulation of polyethylene terephthalate (PET) has become a critical environmental issue. PET hydrolases can break down PET into its building blocks. Recently, we identified a glacial PET hydrolase GlacPETase sharing less than 31% amino acid identity with any known PET hydrolases. In this study, the crystal structure of GlacPETase was determined at 1.8 Å resolution, revealing unique structural features including a distinctive N-terminal disulfide bond and a specific salt bridge network. Site-directed mutagenesis demonstrated that the disruption of the N-terminal disulfide bond did not reduce GlacPETase's thermostability or its catalytic activity on PET. However, mutations in the salt bridges resulted in changes in melting temperature ranging from -8°C to +2°C and the activity on PET ranging from 17.5% to 145.5% compared to the wild type. Molecular dynamics simulations revealed that these salt bridges stabilized the GlacPETase's structure by maintaining their surrounding structure. Phylogenetic analysis indicated that GlacPETase represented a distinct branch within PET hydrolases-like proteins, with the salt bridges and disulfide bonds in this branch being relatively conserved. This research contributed to the improvement of our comprehension of the structural mechanisms that dictate the thermostability of PET hydrolases, highlighting the diverse characteristics and adaptability observed within PET hydrolases.IMPORTANCEThe pervasive problem of polyethylene terephthalate (PET) pollution in various terrestrial and marine environments is widely acknowledged and continues to escalate. PET hydrolases, such as GlacPETase in this study, offered a solution for breaking down PET. Its unique origin and less than 31% identity with any known PET hydrolases have driven us to resolve its structure. Here, we report the correlation between its unique structure and biochemical properties, focusing on an N-terminal disulfide bond and specific salt bridges. Through site-directed mutagenesis experiments and molecular dynamics simulations, the roles of the N-terminal disulfide bond and salt bridges were elucidated in GlacPETase. This research enhanced our understanding of the role of salt bridges in the thermostability of PET hydrolases, providing a valuable reference for the future engineering of PET hydrolases.


Assuntos
Hidrolases , Polietilenotereftalatos , Polietilenotereftalatos/metabolismo , Filogenia , Estabilidade Enzimática , Hidrolases/metabolismo , Dissulfetos , Temperatura
15.
Fish Shellfish Immunol ; 144: 109272, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38061442

RESUMO

Yellow catfish (Pelteobagrus fulvidraco) is an important economic species of freshwater fish, widely distributed in China. Recently, viral diseases of yellow catfish have been identified in Chian (Hubei province), arising more attention to the viral immunity in P. fulvidraco. Tumor necrosis factor (TNF) receptor-associated factor NF-κB activator (TANK)-binding kinase 1 (TBK1) plays an essential role in IFN production and innate antiviral immunity. In the present study, we characterized the P. fulvidraco TBK1 (PfTBK1) and reported its function in interferon response. The full-length open reading frame (ORF) is 2184 bp encoding a protein with 727 amino acids, which is composed of four conserved domains, including KD, ULD, CCD1, and CCD2, similar to TBK1 in other species. Pftbk1 was widely expressed in all detected tissues by qPCR and was not inducible by the spring viremia of carp virus (SVCV), a single-strand RNA virus. In addition, the cellular distribution indicated that PfTBK1 was only located in the cytoplasm. Moreover, PfTBK1 induced strong IFN promoter activities through the Jak-stat pathway, and PfTBK1 interacted with and significantly phosphorylated IFN regulatory factor 3/7 (IRF3/7) in P. fulvidraco, promoting the nuclear translocation of pfIRF3 and PfIRF7, and PfTBK1 upregulated IFN response by PfTBK1-PfIRF3/7 axis. Above all, PfTBK1 triggered IFN response and strongly inhibited the replication of SVCV in EPC cells through induction of IFN downstream IFN-stimulated genes (ISGs). Summarily, this work reveals that PfTBK1 plays a positive regulatory role in IFN induction through the TBK1-IRF3/7 axis, laying a foundation for further exploring the molecular mechanism of the antiviral process in P. fulvidraco.


Assuntos
Peixes-Gato , Interferons , Animais , Interferons/metabolismo , Transdução de Sinais , Fator Regulador 3 de Interferon/genética , Peixes-Gato/genética , Peixes-Gato/metabolismo , Janus Quinases , Fatores de Transcrição STAT , Imunidade Inata/genética
16.
Appl Microbiol Biotechnol ; 108(1): 246, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38421403

RESUMO

Grifola frodosa polysaccharides, especially ß-D-glucans, possess significant anti-tumor, antioxidant and immunostimulatory activities. However, the synthesis mechanism remains to be elucidated. A newly discovered glycosyltransferase UGT88A1 was found to extend glucan chains in vitro. However, the role of UGT88A1 in the growth and polysaccharide synthesis of G. frondosa in vivo remains unclear. In this study, the overexpression of UGT88A1 improved mycelial growth, increased polysaccharide production, and decreased cell wall pressure sensitivity. Biomass and polysaccharide production decreased in the silenced strain, and the pressure sensitivity of the cell wall increased. Overexpression and silencing of UGT88A1 both affected the monosaccharide composition and surface morphology of G. frondosa polysaccharides and influenced the antioxidant activity of polysaccharides from different strains. The messenger RNA expression of glucan synthase (GLS), UTP-glucose-1-phosphate uridylyltransferase (UGP), and UDP-xylose-4-epimerase (UXE) related to polysaccharide synthesis, and genes related to cell wall integrity increased in the overexpression strain. Overall, our study indicates that UGT88A1 plays an important role in the growth, stress, and polysaccharide synthesis of G. frondosa, providing a reference for exploring the pathway of polysaccharide synthesis and metabolic regulation. KEY POINTS: •UGT88A1 plays an important role in the growth, stress response, and polysaccharide synthesis in G. frondosa. •UGT88A1 affected the monosaccharide composition, surface morphology and antioxidant activity of G. frondosa polysaccharides. •UGT88A1 regulated the mRNA expression of genes related to polysaccharide synthesis and cell wall integrity.


Assuntos
Grifola , Piridinas , Ureia/análogos & derivados , Antioxidantes , Glucanos , Glicosiltransferases/genética , Monossacarídeos
17.
Cell Mol Biol Lett ; 29(1): 81, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38816685

RESUMO

Sepsis is defined as life-threatening organ dysfunction caused by a dysregulated host response to infection. Studies have indicated that immune dysfunction plays a central role in the pathogenesis of sepsis. Dendritic cells (DCs) play a crucial role in the emergence of immune dysfunction in sepsis. The major manifestations of DCs in the septic state are abnormal functions and depletion in numbers, which are linked to higher mortality and vulnerability to secondary infections in sepsis. Apoptosis is the most widely studied pathway of number reduction in DCs. In the past few years, there has been a surge in studies focusing on regulated cell death (RCD). This emerging field encompasses various forms of cell death, such as necroptosis, pyroptosis, ferroptosis, and autophagy-dependent cell death (ADCD). Regulation of DC's RCD can serve as a possible therapeutic focus for the treatment of sepsis. Throughout time, numerous tactics have been devised and effectively implemented to improve abnormal immune response during sepsis progression, including modifying the functions of DCs and inhibiting DC cell death. In this review, we provide an overview of the functional impairment and RCD of DCs in septic states. Also, we highlight recent advances in targeting DCs to regulate host immune response following septic challenge.


Assuntos
Células Dendríticas , Sepse , Células Dendríticas/imunologia , Sepse/imunologia , Sepse/patologia , Humanos , Animais , Morte Celular Regulada , Autofagia , Apoptose , Piroptose
18.
Artif Organs ; 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38660762

RESUMO

BACKGROUND: Vascular smooth muscle cells (VSMCs) are commonly used as seed cells in tissue-engineered vascular constructions. However, their variable phenotypes and difficult to control functions pose challenges. This study aimed to overcome these obstacles using a three-dimensional culture system. METHODS: Calf VSMCs were administered tumor necrosis factor-alpha (TNF-α) before culturing in two- and three-dimensional well plates and polyglycolic acid (PGA) scaffolds, respectively. The phenotypic markers of VSMCs were detected by immunofluorescence staining and western blotting, and the proliferation and migration abilities of VSMCs were detected by CCK-8, EDU, cell counting, scratch, and Transwell assays. RESULTS: TNF-α rapidly decreased the contractile phenotypic markers and elevated the synthetic phenotypic markers of VSMCs, as well as markedly increasing the proliferation and migration ability of VSMCs under two- and three-dimensional culture conditions. CONCLUSIONS: TNF-α can rapidly induce a phenotypic shift in VSMCs and change their viability on PGA scaffolds.

19.
Int J Psychiatry Med ; : 912174241256164, 2024 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-38763912

RESUMO

OBJECTIVES: There is an increasing incidence and prevalence of patients with chronic kidney disease (CKD) worldwide. Little is known the prevalence of CKD among older patients with schizophrenia. The purpose of this study was to investigate the prevalence of CKD and its risk factors in older adults with schizophrenia. METHODS: In this cross-sectional study, a convenience sample of 240 patients with schizophrenia age 50 or older were recruited. In addition to demographic and clinical data, participants' estimated glomerular filtration rate was calculated using the Modification of Diet in Renal Disease equation based on age, sex, ethnicity, and serum creatinine level determined from a blood sample taken from participants. RESULTS: The overall prevalence of CKD was 11.3%. Those with CKD group were older, had a longer duration of psychiatric illness, a higher body mass index (BMI), and diagnoses of hypertension compared to those in the non-CKD group. Independent of other risk factors, older age and BMI were significantly associated with CKD. CONCLUSIONS: This study found that the overall prevalence of CKD in older patients with schizophrenia was 11.3%. Risk factors for CKD in this population were older age and higher BMI. In addition to early identification and early treatment of CKD in older patients with schizophrenia, clinicians should actively manage the risk factors identified in this study, such as higher BMI and older age.

20.
J Clin Nurs ; 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38459702

RESUMO

AIMS AND OBJECTIVES: To assess the prognostic accuracy of the surprise question (SQ) when used by nurses working in hospital wards to determine 1-year mortality in acutely hospitalised older patients. BACKGROUND: The predictive accuracy of the SQ, when used by general nurses caring for older hospitalised patients, has not been comprehensively studied. DESIGN: A prospective cohort study. METHODS: This cohort study recruited consecutive 10,139 older patients (aged ≥65 years) who were admitted to Taipei City Hospital and were evaluated for the needs of palliative care in 2015. All patients were followed up for 12 months or until their death. The c-statistic value was calculated to indicate the predictive accuracy of the SQ and Palliative Care Screening Tool (PCST). RESULTS: Of all participants, 18.8% and 18.6% had a SQ response of 'no' and a PCST score ≥4, respectively. After controlling for other covariates, an SQ response of 'no' (adjusted hazard ratio [aHR], 2.05; 95% confidence interval [CI], 1.83-2.31) and a PCST score ≥4 (AHR = 1.50; 95% CI: 1.29-1.75) were found to be the independent predictors for patients' 12-month mortality. The C-statistic values of the SQ and the PCST at recognising patients in their last year of life were .663 and .670, respectively. Moreover, there was moderate concordance (k = .44) between the SQ and the PCST in predicting 12-month mortality. CONCLUSIONS: SQ response of 'no' and a PCST score ≥4 were independent predictors of 12-month mortality in older patients. RELEVANCE TO CLINICAL PRACTICE: The SQ, when used by nurses working in hospital wards, is effective in identifying older patients nearing the end of life, as well as in providing advance care planning for patients. PATIENT OR PUBLIC CONTRIBUTION: Patients' palliative care needs at admission were assessed by general nurses using the SQ and PCST.

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