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1.
Immunity ; 57(6): 1306-1323.e8, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38815582

RESUMO

Group 3 innate lymphoid cells (ILC3s) regulate inflammation and tissue repair at mucosal sites, but whether these functions pertain to other tissues-like the kidneys-remains unclear. Here, we observed that renal fibrosis in humans was associated with increased ILC3s in the kidneys and blood. In mice, we showed that CXCR6+ ILC3s rapidly migrated from the intestinal mucosa and accumulated in the kidney via CXCL16 released from the injured tubules. Within the fibrotic kidney, ILC3s increased the expression of programmed cell death-1 (PD-1) and subsequent IL-17A production to directly activate myofibroblasts and fibrotic niche formation. ILC3 expression of PD-1 inhibited IL-23R endocytosis and consequently amplified the JAK2/STAT3/RORγt/IL-17A pathway that was essential for the pro-fibrogenic effect of ILC3s. Thus, we reveal a hitherto unrecognized migration pathway of ILC3s from the intestine to the kidney and the PD-1-dependent function of ILC3s in promoting renal fibrosis.


Assuntos
Movimento Celular , Fibrose , Rim , Linfócitos , Receptor de Morte Celular Programada 1 , Receptores CXCR6 , Receptores de Interleucina , Transdução de Sinais , Animais , Fibrose/imunologia , Camundongos , Receptores CXCR6/metabolismo , Receptores CXCR6/imunologia , Receptor de Morte Celular Programada 1/metabolismo , Transdução de Sinais/imunologia , Movimento Celular/imunologia , Humanos , Rim/patologia , Rim/imunologia , Rim/metabolismo , Linfócitos/imunologia , Linfócitos/metabolismo , Receptores de Interleucina/metabolismo , Receptores de Interleucina/imunologia , Camundongos Endogâmicos C57BL , Nefropatias/imunologia , Nefropatias/metabolismo , Nefropatias/patologia , Imunidade Inata/imunologia , Camundongos Knockout , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Intestinos/imunologia , Intestinos/patologia
2.
Nano Lett ; 24(15): 4682-4690, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38563501

RESUMO

Multienzyme assemblies mediated by multivalent interaction play a crucial role in cellular processes. However, the three-dimensional (3D) programming of an enzyme complex with defined enzyme activity in vitro remains unexplored, primarily owing to limitations in precisely controlling the spatial topological configuration. Herein, we introduce a nanoscale 3D enzyme assembly using a tetrahedral DNA framework (TDF), enabling the replication of spatial topological configuration and maintenance of an identical edge-to-edge distance akin to natural enzymes. Our results demonstrate that 3D nanoscale enzyme assemblies in both two-enzyme systems (glucose oxidase (GOx)/horseradish peroxidase (HRP)) and three-enzyme systems (amylglucosidase (AGO)/GOx/HRP) lead to enhanced cascade catalytic activity compared to the low-dimensional structure, resulting in ∼5.9- and ∼7.7-fold enhancements over homogeneous diffusional mixtures of free enzymes, respectively. Furthermore, we demonstrate the enzyme assemblies for the detection of the metabolism biomarkers creatinine and creatine, achieving a low limit of detection, high sensitivity, and broad detection range.


Assuntos
Enzimas Imobilizadas , Glucose Oxidase , Enzimas Imobilizadas/química , Peroxidase do Rábano Silvestre/química , Glucose Oxidase/química , DNA/química
3.
Eur Arch Otorhinolaryngol ; 281(4): 1877-1884, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38206391

RESUMO

OBJECTIVES: To assess and compare the effectiveness of various treatment approaches for laryngeal contact granulomas (LCG). METHODS: A retrospective analysis was conducted on a cohort of 45 patients diagnosed with LCG at the Second Affiliated Hospital of Xi'an Jiaotong University from October 2017 to May 2023. Based on the treatment modalities administered, patients were categorized into three groups: acid suppression alone, hormone injection combined with acid suppression, and surgery combined with acid suppression. Subsequently, the study compared differences in treatment efficacy and average healing time among these three groups, using various indicators. RESULTS: The findings indicate that the granuloma size in LCG patients with hoarseness (0.126, 95% CI 0.087-0.288) was significantly greater compared to LCG patients without hoarseness (0.047, 95% CI 0.014-0.083) (P = 0.001). However, there were no significant variations in age, morphology (unlobulated/lobulated), laterality ratio (left/right), sex ratio (male/female), history of tracheal intubation (non-intubation/intubation), and RFS score (RFS > 7/RFS ≤ 7) (P > 0.05), regardless of the presence of hoarseness symptoms. At the treatment observation endpoint of 3 months, the curative ratio in the group receiving hormone injection combined with acid suppression was found to be significantly higher compared to the group receiving acid suppression alone (P = 0.018). In addition, the average healing time of patients in the hormone injection combined with acid suppression group was notably shorter than that of the acid suppression alone group (P = 0.007). CONCLUSIONS: The combination of hormonal injections and acid suppression may enhance the curative ratio and expedite the healing time of LCG.


Assuntos
Granuloma Laríngeo , Rouquidão , Humanos , Masculino , Feminino , Estudos Retrospectivos , Rouquidão/etiologia , Rouquidão/terapia , Granuloma Laríngeo/cirurgia , Granuloma , Hormônios
4.
J Mol Cell Cardiol ; 181: 79-88, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37331466

RESUMO

Heart disease continues to be the leading cause of mortality worldwide, primarily attributed to the restricted regenerative potential of the adult human heart following injury. In contrast to their adult counterparts, many neonatal mammals can spontaneously regenerate their myocardium in the first few days of life via extensive proliferation of the pre-existing cardiomyocytes. Reasons for the decline in regenerative capacity during postnatal development, and how to control it, remain largely unexplored. Accumulated evidence suggests that the preservation of regenerative potential depends on a conducive metabolic state in the embryonic and neonatal heart. Along with the postnatal increase in oxygenation and workload, the mammalian heart undergoes a metabolic transition, shifting its primary metabolic substrate from glucose to fatty acids shortly after birth for energy advantage. This metabolic switch causes cardiomyocyte cell-cycle arrest, which is widely regarded as a key mechanism for the loss of regenerative capacity. Beyond energy provision, emerging studies have suggested a link between this intracellular metabolism dynamics and postnatal epigenetic remodeling of the mammalian heart that reshapes the expression of many genes important for cardiomyocyte proliferation and cardiac regeneration, since many epigenetic enzymes utilize kinds of metabolites as obligate cofactors or substrates. This review summarizes the current state of knowledge of metabolism and metabolite-mediated epigenetic modifications in cardiomyocyte proliferation, with a particular focus on highlighting the potential therapeutic targets that hold promise to treat human heart failure via metabolic and epigenetic regulations.


Assuntos
Cardiopatias , Miócitos Cardíacos , Animais , Recém-Nascido , Adulto , Humanos , Miócitos Cardíacos/metabolismo , Coração , Miocárdio/metabolismo , Cardiopatias/metabolismo , Epigênese Genética , Proliferação de Células , Mamíferos
5.
Analyst ; 148(4): 906-911, 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36692072

RESUMO

Enzyme clustering is widely used in many organisms to increase the catalytic efficiency of cascade reactions. Inspired by nature, organizing enzymes within a cascade reaction also draws much attention in both basic research and industrial processes. An important step for organizing enzymes precisely in vitro is enzyme modification. However, modifying enzymes without sacrificing their activity remains challenging until now. For example, labeling enzymes with DNA, one of the well-established enzyme modification methods, has been shown to significantly reduce the enzymatic activity. Herein we report an enzyme conjugation method that can rescue the reduction of enzymatic activity caused by DNA labeling. We demonstrate that immobilizing DNA-modified enzymes on the vertex of TDNs (tetrahedral DNA nanostructures) enhances the enzymatic activity compared with their unmodified counterparts. Using this strategy, we have further developed an ultra-sensitive and high-throughput electrochemical biosensor for sarcosine detection, which holds great promise for prostate cancer screening.


Assuntos
Técnicas Biossensoriais , Nanoestruturas , Neoplasias da Próstata , Humanos , Masculino , Detecção Precoce de Câncer , Antígeno Prostático Específico , DNA/química , Nanoestruturas/química , Técnicas Biossensoriais/métodos
6.
Nature ; 548(7666): 228-233, 2017 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-28783731

RESUMO

Metabolism has been shown to integrate with epigenetics and transcription to modulate cell fate and function. Beyond meeting the bioenergetic and biosynthetic demands of T-cell differentiation, whether metabolism might control T-cell fate by an epigenetic mechanism is unclear. Here, through the discovery and mechanistic characterization of a small molecule, (aminooxy)acetic acid, that reprograms the differentiation of T helper 17 (TH17) cells towards induced regulatory T (iTreg) cells, we show that increased transamination, mainly catalysed by GOT1, leads to increased levels of 2-hydroxyglutarate in differentiating TH17 cells. The accumulation of 2-hydroxyglutarate resulted in hypermethylation of the Foxp3 gene locus and inhibited Foxp3 transcription, which is essential for fate determination towards TH17 cells. Inhibition of the conversion of glutamate to α-ketoglutaric acid prevented the production of 2-hydroxyglutarate, reduced methylation of the Foxp3 gene locus, and increased Foxp3 expression. This consequently blocked the differentiation of TH17 cells by antagonizing the function of transcription factor RORγt and promoted polarization into iTreg cells. Selective inhibition of GOT1 with (aminooxy)acetic acid ameliorated experimental autoimmune encephalomyelitis in a therapeutic mouse model by regulating the balance between TH17 and iTreg cells. Targeting a glutamate-dependent metabolic pathway thus represents a new strategy for developing therapeutic agents against TH17-mediated autoimmune diseases.


Assuntos
Diferenciação Celular , Epigênese Genética , Linfócitos T Reguladores/citologia , Linfócitos T Reguladores/metabolismo , Células Th17/citologia , Células Th17/metabolismo , Ácido Amino-Oxiacético/farmacologia , Ácido Amino-Oxiacético/uso terapêutico , Animais , Aspartato Aminotransferase Citoplasmática , Diferenciação Celular/efeitos dos fármacos , Encefalomielite Autoimune Experimental/tratamento farmacológico , Encefalomielite Autoimune Experimental/imunologia , Epigênese Genética/efeitos dos fármacos , Feminino , Fatores de Transcrição Forkhead/genética , Glutaratos/metabolismo , Ácidos Cetoglutáricos/metabolismo , Masculino , Camundongos , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/imunologia , Células Th17/efeitos dos fármacos , Células Th17/imunologia , Transaminases/antagonistas & inibidores
7.
Int J Mol Sci ; 24(12)2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37373204

RESUMO

The innate immune pathway serves as the first line of defense against viral infections and plays a crucial role in the host's immune response in clearing viruses. Prior research has indicated that the influenza A virus has developed various strategies to avoid host immune responses. Nevertheless, the role of the NS1 protein of the canine influenza virus (CIV) in the innate immune pathway remains unclear. In this study, eukaryotic plasmids of NS1, NP, PA, PB1, and PB2 were constructed, and it was found that these proteins interact with melanoma differentiation-associated gene 5 (MDA5) and antagonize the activation of IFN-ß promoters by MDA5. We selected the NS1 protein for further study and found that NS1 does not affect the interaction between the viral ribonucleoprotein (RNP) subunit and MDA5, but that it downregulates the expression of the laboratory of genetics and physiology 2 (LGP2) and retinoic acid-inducible gene-I (RIG-I) receptors in the RIG-I pathway. Additionally, NS1 was found to inhibit the expression of several antiviral proteins and cytokines, including MX dynamin like GTPase 1 (MX1), 2'-5'oligoadenylate synthetase (OAS), Signal Transducers and Activators of Transcription (STAT1), tripartite motif 25 (TRIM25), interleukin-2 (IL-2), IFN, IL-8, and IL-1ß. To further investigate the role of NS1, a recombinant H3N2 virus strain (rH3N2) and an NS1-null virus (rH3N2ΔNS1) were rescued using reverse-genetic technology. The rH3N2ΔNS1 virus exhibited lower viral titers compared to rH3N2, but had a stronger activation effect on the receptors LGP2 and RIG-I. Furthermore, when compared to rH3N2, rH3N2ΔNS1 exhibited a more pronounced activation of antiviral proteins such as MX1, OAS, STAT1, and TRIM25, as well as antiviral cytokines such as IL-6, IFN-ß, and IL-1ß. These findings suggest a new mechanism by which NS1, a nonstructural protein of CIV, facilitates innate immune signaling and provides new avenues for the development of antiviral strategies.


Assuntos
Vírus da Influenza A Subtipo H3N2 , Influenza Humana , Animais , Cães , Humanos , Imunidade Inata , Proteínas não Estruturais Virais/metabolismo , Citocinas , Replicação Viral , Antivirais
8.
Sheng Li Xue Bao ; 75(4): 497-502, 2023 Aug 25.
Artigo em Zh | MEDLINE | ID: mdl-37583036

RESUMO

In this study, we used a rat model of pulmonary arterial hypertension (PAH) induced by monocrotaline (MCT) to investigate the role and mechanism of angiotensin (Ang)-(1-7) in regulating pulmonary artery diastolic function. Three weeks after subcutaneous injection of MCT or normal saline, the right ventricular systolic pressure (RVSP) and right ventricular hypertrophy index (RVHI) of rats were detected using a right heart catheter. Vascular endothelium-dependent relaxation was evaluated by acetylcholine (ACh)-induced vasodilation. The relaxation function of vascular smooth muscle was evaluated by sodium nitroprusside (SNP)-induced vasodilation. Human pulmonary artery endothelial cells (HPAECs) were incubated with Ang-(1-7) to measure nitric oxide (NO) release levels. The results showed that compared with control rats, RVSP and RVHI were significantly increased in the MCT-PAH rats, and both ACh or SNP-induced vasodilation were worsened. Incubation of pulmonary artery of MCT-PAH rats with Ang-(1-7) (1 × 10-9-1 × 10-4 mol/L) caused significant vaso-relaxation. Pre-incubation of Ang-(1-7) in the pulmonary artery of MCT-PAH rats significantly improved ACh-induced endothelium-dependent relaxation, but had no significant effect on SNP-induced endothelium-independent relaxation. In addition, Ang-(1-7) treatment significantly increased NO levels in HPAECs. The Mas receptor antagonist A-779 inhibited the effects of Ang-(1-7) on endothelium-dependent relaxation and NO release from endothelial cells. The above results demonstrate that Ang-(1-7) promotes the release of NO from endothelial cells by activating Mas receptor, thereby improving the endothelium-dependent relaxation function of PAH pulmonary arteries.


Assuntos
Hipertensão Pulmonar , Hipertensão Arterial Pulmonar , Ratos , Humanos , Animais , Vasodilatação , Monocrotalina/toxicidade , Ratos Sprague-Dawley , Hipertensão Pulmonar/induzido quimicamente , Células Endoteliais , Artéria Pulmonar , Endotélio , Acetilcolina/farmacologia , Nitroprussiato/farmacologia
9.
BMC Oral Health ; 23(1): 60, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36726081

RESUMO

BACKGROUND: Smoking is an established modifying factor for the host immune response of periodontitis patients. However, its exact influence remains unclear. We aimed to compare the cytokine profile of periodontitis patients with and without smoking habits both before and after periodontal therapy to preliminarily explore its influence on the host immune response to periodontitis. METHODS: The protocol of the present meta-analysis was registered in the International Prospective Register of Systematic Reviews (PROSPERO) under the code CRD42021255656. Meta-analysis was performed for each cytokine if at least three studies were included. We synthesized the evidence to compare the cytokine profile of periodontitis with and without smoking both in gingival cervical fluid (GCF) and serum to explore the impact of smoking on periodontitis both locally and systemically. Moreover, we also compared the cytokine profile of the two groups of patients after periodontal therapy to explore the effect of smoking on the outcome of periodontal therapy. RESULTS: Fifteen studies were included in this meta-analysis. We found that there was no significant difference between the two groups of patients in the baseline cytokine profile. However, after periodontal therapy, smoking periodontitis patients showed significantly higher IL-1ß levels in their GCF than nonsmoking patients. DISCUSSION: There was no significant difference between smoking and nonsmoking periodontitis patients in the baseline cytokine profile. However, after periodontal therapy, smoking periodontitis patients showed significantly higher IL-1ß levels in their GCF than nonsmoking patients, which indicates that smoking may impair the response of periodontitis to periodontal treatment.


Assuntos
Periodontite , Fumar , Humanos , Fumar/efeitos adversos , Líquido do Sulco Gengival , Revisões Sistemáticas como Assunto , Periodontite/terapia , Citocinas
10.
Angew Chem Int Ed Engl ; 62(19): e202218211, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-36857418

RESUMO

Bicyclo[1.1.1]pentane (BCP) motifs are of growing importance to the pharmaceutical industry as sp3 -rich bioisosteres of benzene rings and as molecular building blocks in materials science. Herein we explore the behavior of 1,3-disubstituted BCP moieties on metal surfaces by combining low-temperature scanning tunneling microscopy / non-contact atomic force microscopy studies with density functional theory modeling. We examine the configuration of individual BCP-containing precursors on Au(111), their supramolecular assembly and thermally activated dehalogenative coupling reactions, affording polymeric chains with incorporated electronically isolating units. Our studies not only provide the first sub-molecular insights of the BCP scaffold behavior on surfaces, but also extend the potential application of BCP derivatives towards integration in custom-designed surface architectures.

11.
Circ Res ; 127(7): e148-e165, 2020 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-32693673

RESUMO

RATIONALE: Impaired autophagic flux contributes to ischemia/reperfusion (I/R)-induced cardiomyocyte death, but the underlying molecular mechanisms remain largely unexplored. OBJECTIVE: To determine the role of LAPTM4B (lysosomal-associated transmembrane protein 4B) in the regulation of autophagic flux and myocardial I/R injury. METHODS AND RESULTS: LAPTM4B was expressed in murine hearts but downregulated in hearts with I/R (30 minutes/2 hours) injury and neonatal rat cardiomyocytes with hypoxia/reoxygenation (6 hours/2 hours) injury. During myocardial reperfusion, LAPTM4B-knockout (LAPTM4B-/-) mice had a significantly increased infarct size and lactate dehydrogenase release, whereas adenovirus-mediated LAPTM4B-overexpression was cardioprotective. Concomitantly, LAPTM4B-/- mice showed higher accumulation of the autophagy markers LC3-II (microtubule-associated protein 1A/1B-light chain 3), but not P62, in the I/R heart, whereas they did not alter chloroquine-induced further increases of LC3-II and P62 in both sham and I/R hearts. Conversely, LAPTM4B-overexpression had opposite effects. The hypoxia/reoxygenation-reduced viability of neonatal rat cardiomyocytes, ratio of autolysosomes/autophagosomes, and function of lysosomes were further decreased by LAPTM4B-knockdown but reversed by LAPTM4B-overexpression. Moreover, the LAPTM4B-overexpression-mediated benefits were abolished by knockdown of lysosome-associated membrane protein-2 (an autophagosome-lysosome fusion protein) in vivo and by the autophagy inhibitor bafilomycin A1 in vivo. In contrast, rapamycin (Rapa) successfully restored the impaired autophagic flux in LAPTM4B-/- mice and the subsequent myocardial I/R injury. Mechanistically, LAPTM4B regulated the activity of mTORC1 (mammalian target of rapamycin complex 1) via interacting with mTOR through its EC3 (extracelluar) domain. Thus, mTORC1 was overactivated in LAPTM4B-/- mice, leading to the repression of TFEB (transcription factor EB), a master regulator of lysosomal and autophagic genes, during myocardial I/R. The mTORC1 inhibition or TFEB-overexpression rescued the LAPTM4B-/--induced impairment in autophagic flux and I/R injury, whereas TFEB-knockdown abolished the LAPTM4B-overexpression-mediated recovery of autophagic flux and cardioprotection. CONCLUSIONS: The downregulation of LAPTM4B contributes to myocardial I/R-induced impairment of autophagic flux via modulation of the mTORC1/TFEB pathway. Graphic Abstract: A graphic abstract is available for this article.


Assuntos
Autofagossomos/metabolismo , Autofagia , Lisossomos/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Infarto do Miocárdio/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Miócitos Cardíacos/metabolismo , Animais , Autofagossomos/genética , Autofagossomos/patologia , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Células Cultivadas , Modelos Animais de Doenças , Regulação para Baixo , Lisossomos/genética , Lisossomos/patologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Associadas aos Microtúbulos , Infarto do Miocárdio/genética , Infarto do Miocárdio/patologia , Infarto do Miocárdio/prevenção & controle , Traumatismo por Reperfusão Miocárdica/genética , Traumatismo por Reperfusão Miocárdica/patologia , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miócitos Cardíacos/patologia , Ratos Sprague-Dawley , Proteína Sequestossoma-1/metabolismo , Transdução de Sinais
12.
Nucleic Acids Res ; 48(8): 4448-4462, 2020 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-32232337

RESUMO

Type IA topoisomerases interact with G-strand and T-strand ssDNA to regulate DNA topology. However, simultaneous binding of two ssDNA segments to a type IA topoisomerase has not been observed previously. We report here the crystal structure of a type IA topoisomerase with ssDNA segments bound in opposite polarity to the N- and C-terminal domains. Titration of small ssDNA oligonucleotides to Mycobacterium smegmatis topoisomerase I with progressive C-terminal deletions showed that the C-terminal region has higher affinity for ssDNA than the N-terminal active site. This allows the C-terminal domains to capture one strand of underwound negatively supercoiled DNA substrate first and position the N-terminal domains to bind and cleave the opposite strand in the relaxation reaction. Efficiency of negative supercoiling relaxation increases with the number of domains that bind ssDNA primarily with conserved aromatic residues and possibly with assistance from polar/basic residues. A comparison of bacterial topoisomerase I structures showed that a conserved transesterification unit (N-terminal toroid structure) for cutting and rejoining of a ssDNA strand can be combined with two different types of C-terminal ssDNA binding domains to form diverse bacterial topoisomerase I enzymes that are highly efficient in their physiological role of preventing excess negative supercoiling in the genome.


Assuntos
DNA Topoisomerases Tipo I/química , DNA de Cadeia Simples/metabolismo , Mycobacterium smegmatis/enzimologia , Cristalografia por Raios X , DNA Topoisomerases Tipo I/genética , DNA Topoisomerases Tipo I/metabolismo , Modelos Moleculares , Domínios Proteicos , Deleção de Sequência
13.
Nucleic Acids Res ; 48(13): 7182-7196, 2020 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-32510157

RESUMO

Hippo-YAP signaling pathway functions in early lineage differentiation of pluripotent stem cells, but the detailed mechanisms remain elusive. We found that knockout (KO) of Mst1 and Mst2, two key components of the Hippo signaling in mouse embryonic stem cells (ESCs), resulted in a disruption of differentiation into mesendoderm lineage. To further uncover the underlying regulatory mechanisms, we performed a series of ChIP-seq experiments with antibodies against YAP, ESC master transcription factors and some characterized histone modification markers as well as RNA-seq assays using wild type and Mst KO samples at ES and day 4 embryoid body stage respectively. We demonstrate that YAP is preferentially co-localized with super-enhancer (SE) markers such as Nanog, Sox2, Oct4 and H3K27ac in ESCs. The hyper-activation of nuclear YAP in Mst KO ESCs facilitates the binding of Nanog, Sox2 and Oct4 as well as H3K27ac modification at the loci where YAP binds. Moreover, Mst depletion results in novel SE formation and enhanced liquid-liquid phase-separated Med1 condensates on lineage associated genes, leading to the upregulation of these genes and the distortion of ESC differentiation. Our study reveals a novel mechanism on how Hippo-YAP signaling pathway dictates ESC lineage differentiation.


Assuntos
Diferenciação Celular , Proteínas Serina-Treonina Quinases/fisiologia , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Proteínas de Ciclo Celular/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células-Tronco Embrionárias Murinas , Serina-Treonina Quinase 3 , Fatores de Transcrição/metabolismo , Proteínas de Sinalização YAP
14.
Nucleic Acids Res ; 48(5): 2733-2748, 2020 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-32009146

RESUMO

Family with sequence similarity (FAM46) proteins are newly identified metazoan-specific poly(A) polymerases (PAPs). Although predicted as Gld-2-like eukaryotic non-canonical PAPs, the detailed architecture of FAM46 proteins is still unclear. Exact biological functions for most of FAM46 proteins also remain largely unknown. Here, we report the first crystal structure of a FAM46 protein, FAM46B. FAM46B is composed of a prominently larger N-terminal catalytic domain as compared to known eukaryotic PAPs, and a C-terminal helical domain. FAM46B resembles prokaryotic PAP/CCA-adding enzymes in overall folding as well as certain inter-domain connections, which distinguishes FAM46B from other eukaryotic non-canonical PAPs. Biochemical analysis reveals that FAM46B is an active PAP, and prefers adenosine-rich substrate RNAs. FAM46B is uniquely and highly expressed in human pre-implantation embryos and pluripotent stem cells, but sharply down-regulated following differentiation. FAM46B is localized to both cell nucleus and cytosol, and is indispensable for the viability of human embryonic stem cells. Knock-out of FAM46B is lethal. Knock-down of FAM46B induces apoptosis and restricts protein synthesis. The identification of the bacterial-like FAM46B, as a pluripotent stem cell-specific PAP involved in the maintenance of translational efficiency, provides important clues for further functional studies of this PAP in the early embryonic development of high eukaryotes.


Assuntos
Células-Tronco Embrionárias Humanas/metabolismo , Nucleotidiltransferases/metabolismo , Polinucleotídeo Adenililtransferase/metabolismo , Células Procarióticas/metabolismo , Animais , Biocatálise , Linhagem Celular , Sobrevivência Celular , Desenvolvimento Embrionário , Humanos , Modelos Moleculares , Nucleotidiltransferases/química , Nucleotidiltransferases/genética , Polinucleotídeo Adenililtransferase/química , Ligação Proteica , Domínios Proteicos , RNA/metabolismo , Especificidade por Substrato , Xenopus
15.
Angew Chem Int Ed Engl ; 61(5): e202113590, 2022 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-34708485

RESUMO

Amide bond formation is one of the most important reactions in biochemistry, notably being of crucial importance for the origin of life. Herein, we combine scanning tunneling microscopy and X-ray photoelectron spectroscopy studies to provide evidence for thermally activated abiotic formation of amide bonds between adsorbed precursors through direct carboxyl-amine coupling under ultrahigh-vacuum conditions by means of on-surface synthesis. Complementary insights from temperature-programmed desorption measurements and density functional theory calculations reveal the competition between cross-coupling amide formation and decarboxylation reactions on the Au(111) surface. Furthermore, we demonstrate the critical influence of the employed metal support: whereas on Au(111) the coupling readily occurs, different reaction scenarios prevail on Ag(111) and Cu(111). The systematic experiments signal that archetypical bio-related molecules can be abiotically synthesized in clean environments without water or oxygen.

16.
Pflugers Arch ; 473(7): 1087-1097, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33686477

RESUMO

Heart diseases are prevalent worldwide and account for the highest mortality than any other illness. Although investment in drug discovery and development has increased, the amount of drug approvals has seen a progressive decline. Moreover, adverse side effects to the heart have become the most common reasons for preclinical project cessation, partly due to the lack of suitable humanized preclinical models. Human pluripotent stem cells (hPSCs) have emerged as a powerful non-animal platform to model heart disease, to screen for novel drugs, and to test drug cardiotoxicity in a high-throughput and cost-effective manner. Here, we review and discuss recent breakthroughs in the development of cardiovascular modeling and their current and future applications of hPSC-based drug discovery and testing.


Assuntos
Doenças Cardiovasculares/patologia , Células-Tronco Pluripotentes/fisiologia , Animais , Descoberta de Drogas/métodos , Avaliação Pré-Clínica de Medicamentos/métodos , Humanos , Miócitos Cardíacos/fisiologia
17.
Brief Bioinform ; 20(1): 102-109, 2019 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-28968662

RESUMO

Adenosine-to-inosine (A-to-I) editing by adenosine deaminase acting on the RNA (ADAR) proteins is one of the most frequent modifications during post- and co-transcription. To facilitate the assignment of biological functions to specific editing sites, we designed an automatic online platform to annotate A-to-I RNA editing sites in pre-mRNA splicing signals, microRNAs (miRNAs) and miRNA target untranslated regions (3' UTRs) from human (Homo sapiens) high-throughput sequencing data and predict their effects based on large-scale bioinformatic analysis. After analysing plenty of previously reported RNA editing events and human normal tissues RNA high-seq data, >60 000 potentially effective RNA editing events on functional genes were found. The RNA Editing Plus platform is available for free at https://www.rnaeditplus.org/, and we believe our platform governing multiple optimized methods will improve further studies of A-to-I-induced editing post-transcriptional regulation.


Assuntos
Adenosina Desaminase/metabolismo , Edição de RNA , Proteínas de Ligação a RNA/metabolismo , Software , Regiões 3' não Traduzidas , Adenosina/genética , Adenosina/metabolismo , Processamento Alternativo/genética , Sequência de Bases , Biologia Computacional , Bases de Dados de Ácidos Nucleicos/estatística & dados numéricos , Feminino , Ontologia Genética , Humanos , Inosina/genética , Inosina/metabolismo , Masculino , MicroRNAs/genética , MicroRNAs/metabolismo , Mutação de Sentido Incorreto , Edição de RNA/genética , Precursores de RNA/genética , Precursores de RNA/metabolismo , Análise de Sequência de RNA/estatística & dados numéricos , Máquina de Vetores de Suporte , Distribuição Tecidual
18.
Pulm Pharmacol Ther ; 70: 102072, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34428599

RESUMO

BACKGROUND: Recent studies have shown that endothelin-1 and angiotensin II (AngII) can increase gap junctional intercellular communication (GJIC) by activating Mitogen-activated protein kinases (MAPKs) pathway. However, not only the precise interaction of AngII with Connexin43(Cx43) and the associated functions remain unclear, but also the regulatory role of Cx43 on the AngII-mediated promotion proliferation and migration of VSMCs is poorly understood. MATERIAL AND METHODS: Our research applicated pressure myography measurements, immunofluorescence and Western blot analyses to investigate the changes in physiological indicators in spontaneously hypertensive rats (SHRs) and AngII-stimulated proliferation and migration of A7r5 SMCs(Rat vascular smooth muscle cells). The aim was to elucidate the role of CX43 in hypertension induced by AngII. RESULTS: Chronic ramipril (angiotensin converting enzyme inhibitor) management for SHRs significantly attenuated blood pressure and blood vessel wall thickness, also reduced contraction rate in the cerebral artery. The cerebral artery contraction rates, mRNA and protein expression of Cx43, osteopontin (OPN) and proliferating cell nuclear antigen (PCNA) protein expression in the SHR + ramipril and SHR + ramipril + carbenoxolone (CBX, Cx43 specific blocker) groups were significantly lower than those in the SHR group. Cx43 protein expression and Ser368 phosphorylated Cx43 protein levels increased significantly in AngII-stimulated A7r5 cells. However, the levels of phosphorylated Cx43 decreased after pre-treatment with candesartan (AT1 receptor blocker), GF109203X (protein kinase C (PKC) blocker) and U0126 (mitogen-activated protein kinases/extracellular signal-regulated kinase1/2(MEK/ERK1/2)-specific blocker) in AngII-stimulated A7r5 cells. Cx43 was widely distributed in the cell membrane, nucleus, and cytoplasm of the SMCs. Furthermore, pre-treatment of the AngII- stimulated A7r5 cells with Gap26 (Cx43 blocker) significantly inhibited cell migration and decreased the expression levels of MEK1/2, ERK1/2, P-MEK1/2, and P-ERK1/2. CONCLUSION: Our research confirms that Cx43 plays an important role in the regulation of proliferation and migration of VSMCs via MEK/ERK and PKC signal pathway in AngII-dependent hypertension.


Assuntos
Angiotensina II , Conexina 43/fisiologia , Hipertensão , Miócitos de Músculo Liso/citologia , Angiotensina II/farmacologia , Animais , Proliferação de Células , Músculo Liso Vascular , Ratos
19.
J Asian Nat Prod Res ; 23(4): 385-391, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32865020

RESUMO

A new prenylated coumarin diglycoside, 6-prenylcoumarin-7-O-ß-D-apiofuranosyl-(1→6)-ß-D-glucopyranoside (1) and five known flavonoid glycosides (2-6) were isolated from the leaves and stems of Clausena dunniana. The structures of these isolates were elucidated based on comprehensive MS, UV, IR, and NMR spectroscopic data analysis and comparison with the data reported in literature. Compounds 2-6 are obtained from the title plant for the first time. All these isolates were evaluated for their insulin-release promoting effects, and compounds 1, 2, and 4 exhibited significant activities (2.0 to 3.3-fold higher in comparison with the control, p < 0.01) at 40 µM.[Formula: see text].


Assuntos
Clausena , Insulinas , Cumarínicos/farmacologia , Glicosídeos/farmacologia , Estrutura Molecular
20.
Stem Cells ; 37(4): 489-503, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30599084

RESUMO

Iron homeostasis is crucial for a variety of biological processes, but the biological role of iron homeostasis in pluripotent stem cells (PSCs) remains largely unknown. The present study aimed to determine whether iron homeostasis is involved in maintaining the pluripotency of human PSCs (hPSCs). We found that the intracellular depletion of iron leads to a rapid downregulation of NANOG and a dramatic decrease in the self-renewal of hPSCs as well as spontaneous and nonspecific differentiation. Moreover, long-term depletion of iron can result in the remarkable cell death of hPSCs via apoptosis and necrosis pathways. Additionally, we found that the depletion of iron increased the activity of lipoprotein-associated phospholipase A2 (LP-PLA2) and the production of lysophosphatidylcholine, thereby suppressing NANOG expression by enhancer of zeste homolog 2-mediated trimethylation of histone H3 lysine 27. Consistently, LP-PLA2 inhibition abrogated iron depletion-induced loss of pluripotency and differentiation. Altogether, the findings of our study demonstrates that iron homeostasis, acting through glycerophospholipid metabolic pathway, is essential for the pluripotency and survival of hPSCs. Stem Cells 2019;37:489-503.


Assuntos
Epigênese Genética/genética , Glicerofosfolipídeos/genética , Glicerofosfolipídeos/metabolismo , Ferro/metabolismo , Células-Tronco Pluripotentes/metabolismo , Diferenciação Celular , Homeostase , Humanos , Transfecção
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