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1.
EMBO J ; 42(15): e112900, 2023 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-37350545

RESUMEN

The scaffolding protein angiomotin (AMOT) is indispensable for vertebrate embryonic angiogenesis. Here, we report that AMOT undergoes cleavage in the presence of lysophosphatidic acid (LPA), a lipid growth factor also involved in angiogenesis. AMOT cleavage is mediated by aspartic protease DNA damage-inducible 1 homolog 2 (DDI2), and the process is tightly regulated by a signaling axis including neurofibromin 2 (NF2), tankyrase 1/2 (TNKS1/2), and RING finger protein 146 (RNF146), which induce AMOT membrane localization, poly ADP ribosylation, and ubiquitination, respectively. In both zebrafish and mice, the genetic inactivation of AMOT cleavage regulators leads to defective angiogenesis, and the phenotype is rescued by the overexpression of AMOT-CT, a C-terminal AMOT cleavage product. In either physiological or pathological angiogenesis, AMOT-CT is required for vascular expansion, whereas uncleavable AMOT represses this process. Thus, our work uncovers a signaling pathway that regulates angiogenesis by modulating a cleavage-dependent activation of AMOT.


Asunto(s)
Angiomotinas , Pez Cebra , Animales , Ratones , Pez Cebra/metabolismo , Proteínas de Microfilamentos/metabolismo , Péptido Hidrolasas , Péptidos y Proteínas de Señalización Intercelular/genética
2.
EMBO J ; 42(11): e112126, 2023 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-36919851

RESUMEN

The Hippo pathway is a central regulator of organ size and tumorigenesis and is commonly depicted as a kinase cascade, with an increasing number of regulatory and adaptor proteins linked to its regulation over recent years. Here, we propose that two Hippo signaling modules, MST1/2-SAV1-WWC1-3 (HPO1) and MAP4K1-7-NF2 (HPO2), together regulate the activity of LATS1/2 kinases and YAP/TAZ transcriptional co-activators. In mouse livers, the genetic inactivation of either HPO1 or HPO2 module results in partial activation of YAP/TAZ, bile duct hyperplasia, and hepatocellular carcinoma (HCC). On the contrary, inactivation of both HPO1 and HPO2 modules results in full activation of YAP/TAZ, rapid development of intrahepatic cholangiocarcinoma (iCCA), and early lethality. Interestingly, HPO1 has a predominant role in regulating organ size. HPO1 inactivation causes a homogenous YAP/TAZ activation and cell proliferation across the whole liver, resulting in a proportional and rapid increase in liver size. Thus, this study has reconstructed the order of the Hippo signaling network and suggests that LATS1/2 and YAP/TAZ activities are finetuned by HPO1 and HPO2 modules to cause different cell fates, organ size changes, and tumorigenesis trajectories.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Ratones , Animales , Vía de Señalización Hippo , Transducción de Señal , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Carcinoma Hepatocelular/genética , Proteínas Señalizadoras YAP , Neoplasias Hepáticas/genética , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Carcinogénesis/genética , Transformación Celular Neoplásica , Fosfoproteínas/genética , Fosfoproteínas/metabolismo
3.
Molecules ; 29(9)2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38731608

RESUMEN

In this paper, Cu-BTC derived mesoporous CuS nanomaterial (m-CuS) was synthesized via a two-step process involving carbonization and sulfidation of Cu-BTC for colorimetric glutathione detection. The Cu-BTC was constructed by 1,3,5-benzenetri-carboxylic acid (H3BTC) and Cu2+ ions. The obtained m-CuS showed a large specific surface area (55.751 m2/g), pore volume (0.153 cm3/g), and pore diameter (15.380 nm). In addition, the synthesized m-CuS exhibited high peroxidase-like activity and could catalyze oxidation of the colorless substrate 3,3',5,5'-tetramethylbenzidine to a blue product. Peroxidase-like activity mechanism studies using terephthalic acid as a fluorescent probe proved that m-CuS assists H2O2 decomposition to reactive oxygen species, which are responsible for TMB oxidation. However, the catalytic activity of m-CuS for the oxidation of TMB by H2O2 could be potently inhibited in the presence of glutathione. Based on this phenomenon, the colorimetric detection of glutathione was demonstrated with good selectivity and high sensitivity. The linear range was 1-20 µM and 20-300 µM with a detection limit of 0.1 µM. The m-CuS showing good stability and robust peroxidase catalytic activity was applied for the detection of glutathione in human urine samples.


Asunto(s)
Colorimetría , Cobre , Glutatión , Peróxido de Hidrógeno , Nanoestructuras , Glutatión/análisis , Glutatión/química , Colorimetría/métodos , Cobre/química , Nanoestructuras/química , Catálisis , Peróxido de Hidrógeno/química , Peróxido de Hidrógeno/análisis , Porosidad , Oxidación-Reducción , Ácidos Ftálicos/química , Humanos , Bencidinas/química , Límite de Detección
4.
Angew Chem Int Ed Engl ; 63(7): e202317220, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38153674

RESUMEN

Modulating the microenvironment of single-atom catalysts (SACs) is critical to optimizing catalytic activity. Herein, we innovatively propose a strategy to improve the local reaction environment of Ru single atoms by precisely switching the crystallinity of the support from high crystalline and low crystalline, which significantly improves the hydrogen evolution reaction (HER) activity. The Ru single-atom catalyst anchored on low-crystalline nickel hydroxide (Ru-LC-Ni(OH)2 ) reconstructs the distribution balance of the interfacial ions due to the activation effect of metal dangling bonds on the support. Single-site Ru with a low oxidation state induces the aggregation of hydronium ions (H3 O+ ), leading to the formation of a local acidic microenvironment in alkaline media, breaking the pH-dependent HER activity. As a comparison, the Ru single-atom catalyst anchored on high-crystalline nickel hydroxide (Ru-HC-Ni(OH)2 ) exhibits a sluggish Volmer step and a conventional local reaction environment. As expected, Ru-LC-Ni(OH)2 requires low overpotentials of 9 and 136 mV at 10 and 1000 mA cm-2 in alkaline conditions and operates stably at 500 mA cm-2 for 500 h in an alkaline seawater anion exchange membrane (AEM) electrolyzer. This study provides a new perspective for constructing highly active single-atom electrocatalysts.

5.
Toxicol Appl Pharmacol ; 472: 116574, 2023 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-37271225

RESUMEN

Pyroptosis, an inflammatory programmed cell death, has been suggested as a novel molecular mechanism for the treatment of hepatocellular carcinoma (HCC) with chemotherapeutic agents. Recent studies showed that natural killer (NK) cells could inhibit apoptosis and regulate the progression of pyroptosis in tumor cells. Schisandrin B (Sch B), a lignan isolated from Schisandrae chinensis (Turcz.) Baill. (Schisandraceae) Fructus, has various pharmacological activities including anti-cancer effects. The purpose of this study was to investigate the effect of NK cells on Sch B's regulation of pyroptosis in HCC cells and the molecular mechanisms implicated. The results showed that Sch B alone could decrease cell viability and induce apoptosis in HepG2 cells. However, Sch B induced apoptosis in HepG2 cells was transformed into pyroptosis in the presence of NK cells. The mechanisms underlying NK cell's effect on pyroptosis in Sch B-treated HepG2 cells was related to its activation of caspase 3-Gasdermin E (GSDME). Further studies revealed that NK cell induced caspase 3 activation was derived from its activation of perforin-granzyme B pathway. This study explored the effect of Sch B and NK cells on pyroptosis in HepG2 cells and revealed that perforin-granzyme B-caspase 3-GSDME pathway is involved in the process of pyroptosis. These results proposed an immunomodulatory mechanism of Sch B on HepG2 cells pyroptosis and suggested Sch B as a promising immunotherapy combination partner for the treatment of HCC.


Asunto(s)
Carcinoma Hepatocelular , Lignanos , Neoplasias Hepáticas , Humanos , Piroptosis , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/patología , Células Hep G2 , Caspasa 3/metabolismo , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/patología , Lignanos/farmacología , Células Asesinas Naturales/metabolismo
6.
Cell Biol Toxicol ; 39(6): 2937-2952, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37261679

RESUMEN

We present an integrated analysis of the clinical measurements, immune cells, and plasma lipidomics of 2000 individuals representing different age stages. In the study, we explore the interplay of systemic lipids metabolism and circulating immune cells through in-depth analysis of immune cell phenotype and function in peripheral dynamic lipids environment. The population makeup of circulation lymphocytes and lipid metabolites changes dynamically with age. We identified a major shift between young group and middle age group, at which point elevated, immune response is accompanied by the elevation of specific classes of peripheral phospholipids. We tested the effects in mouse model and found that 10-month-dietary added phospholipids induced T-cell senescence. However, the chronic malignant disease, the crosstalk between systemic metabolism and immunity, is completely changed. In cancer patients, the unusual plasma cholesteryl esters emerged, and free fatty acids decreased. The study reveals how immune cell classes and peripheral metabolism coordinate during age acceleration and suggests immune senescence is not isolated, and thus, system effect is the critical point for cell- and function-specific immune-metabolic targeting. • The study identifies a major shift of immune phenotype between young group and middle age group, and the immune response is accompanied by the elevation of specific classes of peripheral phospholipids; • The study suggests potential implications for translational studies such as using metabolic drug to regulate immune activity.


Asunto(s)
Fosfolípidos , Agotamiento de Células T , Persona de Mediana Edad , Ratones , Animales , Humanos , Fosfolípidos/análisis , Fosfolípidos/metabolismo , Ácidos Grasos/metabolismo , Ésteres del Colesterol
7.
J Biochem Mol Toxicol ; 37(12): e23508, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37623816

RESUMEN

Wogonin (5,7-dihydroxy-8-methoxyflavone), a natural flavonoid compound in herbal plants, can suppress growth in hepatocellular carcinoma (HCC). However, the microRNA (miRNA) expression profiles that are influenced by wogonin have not been thoroughly described. To explore the novel miRNAs and the biological mechanism underlying the effect of wogonin on HCC cells. The effect of wogonin on Huh7 cell growth was assessed both in vitro and in vivo. The expression profiles of miRNAs were obtained by small RNA sequencing. Luciferase reporter experiment and bioinformatics analysis were conducted to determine whether tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein zeta (YWHAZ) can bind to miR-27b-5p. Effects of the ectopic expression of YWHAZ and miR-27b-5p on Huh7 cells proliferation and apoptosis were evaluated. Furthermore, the cell cycle, apoptosis and multiple signaling pathway-related molecules were detected by Western blot analysis. Wogonin substantially inhibited the growth of Huh7 cells both in vitro and in vivo. Seventy miRNAs exhibited greater than twofold changes in wogonin-treated cells. Upregulation of miR-27b-5p inhibited Huh7 cell proliferation, and the anticancer effect of wogonin was reversed after miR-27b-5p knockdown. miR-27b-5p directly targeted YWHAZ in HCC cells. The proliferation-inhibiting effect of miR-27b-5p was revoked by YWHAZ overexpression. Meanwhile, inhibition of HCC growth was achieved by downregulating YWHAZ. Wogonin exerted antitumor activity through multiple signaling molecules, such as focal adhesion kinase, protein kinase B, mammalian target of rapamycin and molecules related to apoptosis and cell cycle by upregulating miR-27b-5p and downregulating YWHAZ. Our findings suggest that miR-27b-5p/YWHAZ axis contributes to the inhibitory effect of wogonin in HCC by targeting related genes and multiple signaling pathways.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroARNs , Humanos , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Línea Celular Tumoral , MicroARNs/genética , MicroARNs/metabolismo , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , Movimiento Celular/genética , Proteínas 14-3-3/genética , Proteínas 14-3-3/metabolismo
8.
Pharm Biol ; 61(1): 621-629, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37010139

RESUMEN

CONTEXT: Schisandrin B (Sch B), an active ingredient from Schisandrae chinensis (Turcz.) Baill. (Schisandraceae) Fructus, possesses diverse pharmacological activities including antitumor, anti-inflammation, and hepatoprotection. OBJECTIVE: To explore the effect of Sch B on activated HSCs senescence in hepatic fibrosis and the mechanisms implicated. MATERIALS AND METHODS: ICR mice with CCl4-induced hepatic fibrosis were supplemented with Sch B (40 mg/kg) for 30 d and LX2 cells were treated with Sch B (5, 10 and 20 µM) for 24 h. Cellular senescence was assessed by senescence-related indicators senescence-associated ß-galactosidase (SA-ß-gal) activity and the expression of p16, p21, p53, γ-H2AX, H3K9me3, TERT, TRF1, and TRF2. Ferric ammonium citrate (FAC) and NCOA4 siRNA were used to evaluate the mechanisms underlying Sch B's regulation of cellular senescence. RESULTS: Sch B (40 mg/kg) reduced serum levels of AST and ALT (53.2% and 63.6%), alleviated hepatic collagen deposition, and promoted activated HSCs senescence in mice. Treatment with Sch B (20 µM) decreased cell viability to 80.38 ± 4.87% and elevated SA-ß-gal activity, with the levels of p16, p21 and p53 increased by 4.5-, 2.9-, and 3.5-fold and the levels of TERT, TRF1 and TRF2 decreased by 2.4-, 2.7-, and 2.6-fold in LX2 cells. FAC (400 µM) enhanced Sch B's effect mentioned above. NCOA4 siRNA weakened the effects of Sch B on iron deposition and HSCs senescence. CONCLUSIONS: Sch B could ameliorate hepatic fibrosis through the promotion of activated HSCs senescence, which might be attributed to its induction of NCOA4-mediated ferritinophagy and subsequent iron overload.


Asunto(s)
Células Estrelladas Hepáticas , Proteína p53 Supresora de Tumor , Ratones , Animales , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Proteína p53 Supresora de Tumor/farmacología , Ratones Endogámicos ICR , Cirrosis Hepática/patología , Senescencia Celular , ARN Interferente Pequeño , Factores de Transcripción/metabolismo , Coactivadores de Receptor Nuclear/genética , Coactivadores de Receptor Nuclear/metabolismo
10.
Eur Radiol ; 32(12): 8649-8658, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35739284

RESUMEN

OBJECTIVES: Chronic occupational manganese (Mn) exposure is characterized by motor and cognitive dysfunction. This study aimed to investigate structural abnormalities in Mn-exposed welders compared to healthy controls (HCs). METHODS: Thirty-five HCs and forty Mn-exposed welders underwent magnetic resonance imaging (MRI) scans in this study. Based on T1-weighted MRI, the voxel-based morphometry (VBM), structural covariance, and receiver operating characteristic (ROC) curve were applied to examine whole-brain structural changes in Mn-exposed welders. RESULTS: Compared to HCs, Mn-exposed welders had altered gray matter volume (GMV) mainly in the medial prefrontal cortex, lentiform nucleus, hippocampus, and parahippocampus. ROC analysis indicated the potential highest classification power of the hippocampus/parahippocampus. Moreover, distinct structural covariance patterns in the two groups were associated with regions, mainly including the thalamus, insula, amygdala, sensorimotor area, and middle temporal gyrus. No significant relationships were found between the findings and clinical characteristics. CONCLUSIONS: Our findings showed Mn-exposed welders had changed GMV and structural covariance patterns in some regions, which implicated in motivative response, cognitive control, and emotional regulation. These results might provide preliminary evidence for understanding the pathophysiology of Mn overexposure. KEY POINTS: • Chronic Mn exposure might be related to abnormal brain structural neural mechanisms. • Mn-exposed welders had morphological changes in brain regions implicated in emotional modulation, cognitive control, and motor-related response. • Altered gray matter volume in the hippocampus/parahippocampus and putamen might serve as potential biomarkers for Mn overexposure.


Asunto(s)
Sustancia Gris , Manganeso , Humanos , Sustancia Gris/diagnóstico por imagen , Sustancia Gris/patología , Manganeso/efectos adversos , Obreros Metalúrgicos , Imagen por Resonancia Magnética/métodos , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Neuroimagen
11.
Ecotoxicol Environ Saf ; 234: 113395, 2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-35298966

RESUMEN

Bisphenol A (BPA) is a widespread endocrine disruptor that induces the impairment of immune cells, but the mechanism remains unknown. Macrophages are one of the most important immune cells in innate and adaptive immunity. In this study, we aimed to probe the effects of BPA on the damage of RAW264.7 cells and its mechanisms of action, especially focusing on the relationship between autophagy and apoptosis. Cells were pretreated with 10 mg/L LPS, or added autophagy activator RAPA, autophagy inhibitor 3-MA or Bcl-2 inhibitor ABT-737, then treated with BPA (0, 10, 100 and 200 µmol/L) for 12 h. Results have shown that BPA decreased the cell viability and disrupted secretory function by promoting pro-inflammatory cytokines TNF-α and IL-6 and reducing anti-inflammatory cytokines IL-10 TGF-ß, as well as phagocytic ability. Moreover, autophagy was inhibited by BPA through decreasing p-AMPK/AMPK and increasing p-mTOR/mTOR, and further down-regulating autophagy proteins ATG6, LC3II/I ratio, and up-regulating autophagy flux protein p62. Additionally, BPA significantly increased Bax/Bcl-2 ratio, Caspase-3 expression and apoptosis rate. We found that RAPA ameliorated the cell viability, Bax/Bcl-2 ratio, and macrophage function damage induced by BPA. Intriguingly, ABT-737 might promote ATG6 expression. In summary, our study demonstrated that the effects of BPA on macrophages seemed to be mediated by inhibiting AMPK/mTOR-dependent autophagy and inducing apoptosis via endogenous mitochondrial pathway. Both Bcl-2 and ATG6 were involved in the regulation of apoptosis and autophagy by BPA. These findings provide a broader perspective for understanding the interaction between autophagy and apoptosis in BPA-induced immune cell injury.

12.
Ecotoxicol Environ Saf ; 248: 114329, 2022 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-36442400

RESUMEN

The public health harms caused by fine particulate matter (PM2.5) have become a global focus, with PM2.5 exposure recognized as a critical risk factor for global morbidity and mortality. Chronic inflammation is the common pathophysiological feature of respiratory diseases induced by PM2.5 and is the most critical cause of all these diseases. However, presently there is a lack of effective preventive and therapeutic approaches for inflammatory lung injuries caused by PM2.5 exposure. Baicalin is a herb-derived effective flavonoid compound with multiple health benefits. This study established a murine lung inflammatory injury model via inhalation of PM2.5 aerosols. The data showed that after baicalin intervention, lung injury pathological score of baicalin (4.16 ± 0.54, 3.33 ± 0.76, 4.00 ± 0.45) and claricid (3.00 ± 0.78) treatments were markedly lower than PM2.5-treated mice (6.17 ± 0.31), and pathological damage was alleviated. Compared to the PM2.5 group, the spleen and lung indexes in the baicalin and claricid groups were significantly reduced. The inflammatory cytokines of TNF-α, IL-18, and IL-1ß in serum, alveolar lavage fluid, and lung tissue were significantly decreased in the baicalin and claricid groups. The expressions of inflammatory pathway-related genes and proteins HMGB1, NLRP3, ASC, and caspase-1 were up-regulated in the PM2.5 group. The expressions of these genes and proteins were significantly decreased following baicalin treatment. The lung function indicators showed that the MV (65.94 ± 8.19 mL), sRaw (1.79 ± 0.08 cm H2O.s), and FRC (0.52 ± 0.01 mL) in the PM2.5 group were higher than in the control and baicalin groups, and respiratory function was improved by baicalin. PM2.5 exposure markedly altered the bacterial composition at the genus level. The dominant flora relative abundances of uncultured_bacterium_f_Muribaculaceae, Streptococcus, and Lactobacillus, were decreased from the control group (9.20%, 8.53%, 6.21%) to PM2.5 group (6.26%, 5.49%, 4.77%), respectively. Following baicalin intervention, the relative abundances were 9.72%, 6.65%, and 3.57%, respectively. Therefore, baicalin could potentially prevent and improve mice lung inflammatory injury induced by PM2.5 exposure. Baicalin might provide a protective role by balancing oropharyngeal microbiota and affecting the expression of the HMGB1/Caspase1 pathway.


Asunto(s)
Proteína HMGB1 , Lesión Pulmonar , Ratones , Animales , Lesión Pulmonar/inducido químicamente , Lesión Pulmonar/tratamiento farmacológico , Ratones Endogámicos , Flavonoides/farmacología , Flavonoides/uso terapéutico , Pulmón
13.
J Cell Mol Med ; 25(15): 7354-7366, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34190396

RESUMEN

Although recent evidence has shown that hepatocyte senescence plays a crucial role in the pathogenesis and development of non-alcoholic fatty liver disease (NAFLD), the mechanism is still not clear. The purpose of this study was to investigate the signal transduction pathways involved in the senescence of hepatocyte, in order to provide a potential strategy for blocking the process of NAFLD. The results confirmed that hepatocyte senescence occurred in HFD-fed Golden hamsters and PA-treated LO2 cells as manifested by increased levels of senescence marker SA-ß-gal, p16 and p21, heterochromatin marker H3K9me3, DNA damage marker γ-H2AX and decreased activity of telomerase. Further studies demonstrated that iron overload could promote the senescence of hepatocyte, whereas the overexpression of Yes-associated protein (YAP) could blunt iron overload and alleviate the senescence of hepatocyte. Of importance, depression of lncRNA MAYA (MAYA) reduced iron overload and cellular senescence via promotion of YAP in PA-treated hepatocytes. These effects were further supported by in vivo experiments. In conclusion, these data suggested that inhibition of MAYA could up-regulate YAP, which might repress hepatocyte senescence through modulating iron overload. In addition, these findings provided a promising option for heading off the development of NAFLD by abrogating hepatocyte senescence.


Asunto(s)
Senescencia Celular , Hepatocitos/metabolismo , Hierro/metabolismo , Enfermedad del Hígado Graso no Alcohólico/metabolismo , ARN Largo no Codificante/genética , Proteínas Señalizadoras YAP/metabolismo , Animales , Línea Celular , Cricetinae , Daño del ADN , Hepatocitos/fisiología , Humanos , Mesocricetus , Enfermedad del Hígado Graso no Alcohólico/genética , ARN Largo no Codificante/metabolismo , Proteínas Señalizadoras YAP/genética
14.
Cell Biol Toxicol ; 37(3): 367-378, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-32656717

RESUMEN

CD8+T cells play an important role in controlling infections and tumorigenesis in vivo. naïve CD8+T cells exponentially expand and exert effector functions in response to TCR ligation. After antigen clearance, most effector CD8+T cells (Teff) experience activation-induced cell death, only a small portion becomes long-lived memory T cells (Tmem). The cell-intrinsic mechanisms driving the differentiation need further understanding. Here we used combined transposase-accessible chromatin (ATAC-seq) technology and RNA-seq analysis to explore chromatin accessibility in CD8+T cell subsets (naïve T cells, Teff, and Tmem). The data demonstrates different chromatin openness of CD8+T cell states is associated with metabolic regulation and the high accessibility of upstream binding site SP1 emerged as critical transcription factor for both Teff and Tmem in fatty acid oxidation (FAO) and glycolysis. The different presence of accessible regions in CD8+T cell subsets provides a novel perspective for understanding epigenetic mechanisms underlying T cell differentiation and related immune response.


Asunto(s)
Diferenciación Celular/genética , Cromatina/genética , Factor de Transcripción Sp1/genética , Transposasas/genética , Linfocitos T CD8-positivos/citología , Linfocitos T CD8-positivos/metabolismo , Carcinogénesis/genética , Carcinogénesis/patología , Secuenciación de Inmunoprecipitación de Cromatina/métodos , Humanos , Infecciones/genética , Infecciones/patología , RNA-Seq/métodos
15.
Angew Chem Int Ed Engl ; 60(41): 22276-22282, 2021 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-34427019

RESUMEN

Designing definite metal-support interfacial bond is an effective strategy for optimizing the intrinsic activity of noble metals, but rather challenging. Herein, a series of quantum-sized metal nanoparticles (NPs) anchored on nickel metal-organic framework nanohybrids (M@Ni-MOF, M=Ru, Ir, Pd) are rationally developed through a spontaneous redox strategy. The metal-oxygen bonds between the NPs and Ni-MOF guarantee structural stability and sufficient exposure of the surface active sites. More importantly, such precise interfacial feature can effectively modulate the electronic structure of hybrids through the charge transfer of the formed Ni-O-M bridge and then improves the reaction kinetics. As a result, the representative Ru@Ni-MOF exhibits excellent hydrogen evolution reaction (HER) activity at all pH values, even superior to commercial Pt/C and recent noble-metal catalysts. Theoretical calculations deepen the mechanism understanding of the superior HER performance of Ru@Ni-MOF through the optimized adsorption free energies of water and hydrogen due to the interfacial-bond-induced electron redistribution.

16.
Biochem Biophys Res Commun ; 531(2): 96-104, 2020 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-32773110

RESUMEN

Yes-associated protein (YAP) is a key downstream effector of the highly conserved Hippo signaling pathway, which regulates organ size, regeneration and tumorigenesis. Known classically to function as a transcriptional co-activator, YAP interacts with TEA domain transcription factors (TEAD1-4) to induce expression of target genes. However, a number of genes are repressed upon YAP activation, suggesting a transcriptional repressor role of YAP. Here, we report that TP73 is a direct target gene of YAP, and its transcription is repressed by YAP in a TEAD-independent manner. On the other hand, WW domains of YAP are indispensable for the regulation of TP73 expression, which may recruit YAP to TP73 gene though interaction with ZEB1 and/or RUNX2, two transcriptional repressors. Moreover, YAP-mediated repression of TP73 promotes cancer cell survival in the presence of chemotherapeutic agents, suggesting YAP-TP73 signaling as a mechanism for cancer cell resistance to chemotherapies.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Transducción de Señal , Factores de Transcripción/metabolismo , Transcripción Genética , Proteína Tumoral p73/genética , Proteínas Adaptadoras Transductoras de Señales/química , Secuencia de Bases , Línea Celular Tumoral , Subunidad alfa 1 del Factor de Unión al Sitio Principal/metabolismo , Resistencia a Antineoplásicos , Vía de Señalización Hippo , Humanos , Dominios Proteicos , Proteínas Represoras/metabolismo , Factores de Transcripción/química , Proteína Tumoral p73/metabolismo , Proteínas Señalizadoras YAP , Homeobox 1 de Unión a la E-Box con Dedos de Zinc/metabolismo
17.
Plant Cell Environ ; 43(5): 1175-1191, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-31990075

RESUMEN

Photorespiratory hydrogen peroxide (H2 O2 ) plays key roles in pathogenesis responses by triggering the salicylic acid (SA) pathway in Arabidopsis. However, factors linking intracellular H2 O2 to activation of the SA pathway remain elusive. In this work, the catalase-deficient Arabidopsis mutant, cat2, was exploited to elucidate the impact of S-nitrosoglutathione reductase 1 (GSNOR1) on H2 O2 -dependent signalling pathways. Introducing the gsnor1-3 mutation into the cat2 background increased S-nitrosothiol levels and abolished cat2-triggered cell death, SA accumulation, and associated gene expression but had little additional effect on the major components of the ascorbate-glutathione system or glycolate oxidase activities. Differential transcriptome profiles between gsnor1-3 and cat2 gsnor1-3 together with damped ROS-triggered gene expression in cat2 gsnor1-3 further indicated that GSNOR1 acts to mediate the SA pathway downstream of H2 O2 . Up-regulation of GSNOR activity was compromised in cat2 cad2 and cat2 pad2 mutants in which glutathione accumulation was genetically prevented. Experiments with purified recombinant GSNOR revealed that the enzyme is posttranslationally regulated by direct denitrosation in a glutathione-dependent manner. Together, our findings identify GSNOR1-controlled nitrosation as a key factor in activation of the SA pathway by H2 O2 and reveal that glutathione is required to maintain this biological function.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Glutatión Reductasa/metabolismo , Glutatión/metabolismo , Peróxido de Hidrógeno/metabolismo , Oxidación-Reducción , Transducción de Señal , Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas , Microscopía Confocal , Nitrosación , Estrés Oxidativo , Reguladores del Crecimiento de las Plantas/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Ácido Salicílico/metabolismo
18.
Plant Cell Environ ; 42(12): 3182-3196, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31369162

RESUMEN

A biological clock activated by oscillating signals, known as root clock, has been linked to lateral root (LR) formation and is essential for regular LR spacing along the primary root. However, it remains unclear how this internal mechanism is influenced by environmental factors known to affect the LR pattern. Here, we report that excessive cadmium (Cd) inhibits LR formation by disrupting the lateral root cap (LRC)-programmed cell death (PCD)-regulated root clock. Cd restricts the frequency of the oscillating signal rather than its amplitude. This could be attributed to the inhibition on meristematic activity by Cd, which resulted in decreased LRC cell number and LRC-PCD frequency. Genetic evidence further showed that LRC cell number is positively correlated with root resistance to Cd. Our study reveals root cap dynamics as a novel mechanism mediating root responses to Cd, providing insight into the signalling pathways of the root clock responding to environmental cues.


Asunto(s)
Relojes Biológicos , Cadmio/toxicidad , Raíces de Plantas/crecimiento & desarrollo , Estrés Fisiológico/efectos de los fármacos , Apoptosis/efectos de los fármacos , División Celular/efectos de los fármacos , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Meristema/efectos de los fármacos , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/genética , Plantas/efectos de los fármacos , Plantas/genética , Especificidad de la Especie , Estrés Fisiológico/genética
20.
Phys Chem Chem Phys ; 21(21): 11004-11010, 2019 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-31089593

RESUMEN

Benzoquinone (BQ)-based macrocyclic compounds have shown great potential as cathode materials for lithium-ion batteries (LIBs) owing to their high redox potential and specific capacity. However, such materials usually have complex structures, which impede the investigation of lithiation mechanisms. Herein, we take Calix[4]quinone (C4Q) molecule as an example to develop a viable mechanism investigation method for such materials. The lithiation profile of C4Q is determined by condensed Fukui function which provides the reaction sites and orders. A correction of redox potential is proposed by leaving out the ion-transfer effect during the redox reaction based on Gibbs free energy change. The redox potential obtained by this approach shows high consistency with the experimental results. Moreover, this method can also be well extended to study the lithiation mechanism of another BQ-based macrocyclic compound (Pillar[5]quinone). Our results are promising to more deeply understand the reaction mechanism and predict the redox potential of new BQ-based macrocyclic compounds for LIBs.

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