RESUMEN
The nuclear receptor corepressor (NCoR) forms a complex with histone deacetylase 3 (HDAC3) that mediates repressive functions of unliganded nuclear receptors and other transcriptional repressors by deacetylation of histone substrates. Recent studies provide evidence that NCoR/HDAC3 complexes can also exert coactivator functions in brown adipocytes by deacetylating and activating PPARγ coactivator 1α (PGC1α) and that signaling via receptor activator of nuclear factor kappa-B (RANK) promotes the formation of a stable NCoR/HDAC3/PGC1ß complex that coactivates nuclear factor kappa-B (NFκB)- and activator protein 1 (AP-1)-dependent genes required for osteoclast differentiation. Here, we demonstrate that activation of Toll-like receptor (TLR) 4, but not TLR3, the interleukin 4 (IL4) receptor nor the Type I interferon receptor, also promotes assembly of an NCoR/HDAC3/PGC1ß coactivator complex. Receptor-specific utilization of TNF receptor-associated factor 6 (TRAF6) and downstream activation of extracellular signal-regulated kinase 1 (ERK1) and TANK-binding kinase 1 (TBK1) accounts for the common ability of RANK and TLR4 to drive assembly of an NCoR/HDAC3/PGC1ß complex in macrophages. ERK1, the p65 component of NFκB, and the p300 histone acetyltransferase (HAT) are also components of the induced complex and are associated with local histone acetylation and transcriptional activation of TLR4-dependent enhancers and promoters. These observations identify a TLR4/TRAF6-dependent signaling pathway that converts NCoR from a corepressor of nuclear receptors to a coactivator of NFκB and AP-1 that may be relevant to functions of NCoR in other developmental and homeostatic processes.
Asunto(s)
Histonas , Factor 6 Asociado a Receptor de TNF , Activación Transcripcional , Proteínas Co-Represoras/genética , Histonas/genética , Histonas/metabolismo , Factor 6 Asociado a Receptor de TNF/genética , Factor 6 Asociado a Receptor de TNF/metabolismo , Factor de Transcripción AP-1/metabolismo , Receptor Toll-Like 4/metabolismo , Transducción de Señal , FN-kappa B/genética , FN-kappa B/metabolismo , Receptores Citoplasmáticos y Nucleares/metabolismoRESUMEN
Potassium-ion batteries (PIBs) have attracted ever-increasing interest due to the abundant potassium resources and low cost, which are considered a sustainable energy storage technology. However, the graphite anodes employed in PIBs suffer from low capacity and sluggish reaction kinetics caused by the large radius of potassium ions. Herein, we report nitrogen-doped, defect-rich hollow carbon nanospheres with contact curved interfaces (CCIs) on carbon nanotubes (CNTs), namely CCI-CNS/CNT, to boost both electron transfer and potassium-ion adsorption. Density functional theory calculations validate that engineering CCIs significantly augments the electronic state near the Fermi level, thus promoting electron transfer. In addition, the CCIs exhibit a pronounced affinity for potassium ions, promoting their adsorption and subsequently benefiting potassium storage. As a result, the rationally designed CCI-CNS/CNT anode shows remarkable cyclic stability and rate capability. This work provides a strategy for enhancing the potassium storage performance of carbonaceous materials through CCI engineering, which can be further extended to other battery systems.
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One new ylangene-type sesquiterpene glycoside, findlayanoside C (1), and one new picrotoxane-type sesquiterpene glycoside, findlayanoside D (3), together with five known sesquiterpene glycosides, dendrofindlayanoside C (2), dendronobiloside B (4), dendronobiloside A (5), dendroside F (6) and dendromoniliside D (7), have been isolated from the stems of Dendrobium findleyanum. The structures of compounds 1 and 3 were elucidated by means of extensive spectroscopic analyses, and their absolute configuration were confirmed by electronic circular dichroism (ECD) calculations. Cytotoxic activity assays against SMMC-7721, A-549 and MCF-7 human cancer cell lines revealed IC50 values of 10.12, 12.32 and 14.13 µM for compound 1, and of 9.25, 13.16 and 16.26 µM for compound 2. This study enriches the anti-tumour sesquiterpenoids composition of D. findleyanum.
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Anti/deicing coatings that combine active and passive methods can utilize various energy sources to achieve anti/deicing effects. However, poor photothermal or electrothermal performance and inevitable heat loss often reduce their anti/deicing efficiency. Herein, copper sulfide loaded activated biochar (AC@CuS) as photo/electric material, polydimethylsiloxane as hydrophobic component, thermally expandable microspheres as foaming agent, and an anti/deicing coating integrating thermal insulation, superhydrophobicity, photo/electrothermal effects was successfully constructed. Benefiting from the synergistic effect of superhydrophobicity and thermal insulation, the freezing time of water droplets on the coating surface is extended from 150 to 2140 s, showing excellent passive anti-icing performance. AC@CuS exhibits photo/electrothermal effects, and porous expanded microspheres reduce heat loss, which endows the coating with desirable photo/electrothermal conversion performance. Under the conditions of 0.2 W/cm2 electric power density (EPD) and 0.1 W/cm2 optical power density (OPD), the temperature of the coating increases from 24 to 96.4 and 113 °C, respectively. Interestingly, with a coheating of 0.05 W/cm2 weaker OPD and 0.05 W/cm2 lower EPD, the ice on the coating surface can be quickly melted in 2.5 min, showing synergistic deicing performance. In addition, the WCA of the prepared coating remains above 150° after mechanical damage, rain impact, UV irradiation, chemical corrosion, and high-temperature treatment, and good superhydrophobic durability ensures the anti/deicing durability of the coating.
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Stress granules (SGs) are dynamic biomolecular condensates that form in the cytoplasm in response to cellular stress, encapsulating proteins and RNAs. Methylation is a key factor in the assembly of SGs, with PRMT1, which acts as an arginine methyltransferase, localizing to SGs. However, the precise mechanism of PRMT1 localization within SGs remains unknown. In this study, we identified that Caprin1 plays a primary role in the recruitment of PRMT1 to SGs, particularly through its C-terminal domain. Our findings demonstrate that Caprin1 serves a dual function as both a linker, facilitating the formation of a PRMT1-G3BP1 complex, and as a spacer, preventing the aberrant formation of SGs under non-stress conditions. This study sheds new lights on the regulatory mechanisms governing SG formation and suggests that Caprin1 plays a critical role in cellular responses to stress.
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Exploring efficient and comprehensive utilization of agricultural waste to produce high value-added products has been global research hotspot. In this study, a novel process for integrated production of xylose and docosahexaenoic acid (DHA) from hemicellulose and cellulose in corncob was developed. Corncob was treated with dilute H2SO4 at 121 °C for 1 h and xylose was readily produced with a recovery yield of 79.35 %. The corncob residue was then subject to alkali pretreatment under optimized conditions of 0.1 g NaOH/g dry solid, 60 °C for 2 h, and the contents of cellulose, hemicellulose, and lignin in the resulting residue were 87.49 %, 7.58 % and 2.31 %, respectively. The cellulose in the residue was easily hydrolyzed by cellulase, yielding 74.87 g/L glucose with hydrolysis efficiency of 77.02 %. Remarkably, the corncob residue hydrolysate supported cell growth and DHA production in Schizochytrium sp. ATCC 20888 well, and the maximum biomass of 32.71 g/L and DHA yield of 4.63 g/L were obtained, with DHA percentage in total fatty acids of 36.89 %. This study demonstrates that the corncob residue generated during xylose production, rich in cellulose, can be effectively utilized for DHA production by Schizochytrium sp., offering a cost-effective and sustainable alternative to pure glucose.
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PURPOSE: Patients have been severely suffered from cancer associated pain, and pancreatic cancer is the most severe form of cancer associated with pain. There are very few options available to manage it. The present report evaluated the effect of 5HT2A on pancreatic cancer associated pain. METHODS: Pancreatic cancer was induced by injecting SW 1,990 cells (~3×106 in a 20 µL suspension) into the pancreas and formed a 2-3-mm vesicle using an inoculator fitted with a 26-gauge needle in BALB/c-nu mice. Survival rate and body weight of the mice were observed. Pain behaviour testing was performed at the end of each week (third and fourth week) after surgery. Inflammatory mediators and HDAC 2 proteins were determined in the spinal tissue using quantitative real-time polymerase chain reaction. RESULTS: There was improvement in the survival rate and body weight in 5HT2A antagonist treated group than pancreatic cancer group of mice. Moreover, 5HT2A antagonist ameliorated the alteration in pain behaviour of pancreatic cancer mice. mRNA expression of HDAC2 and level of inflammatory cytokines were reduced in the spinal tissue of 5HT 2A antagonist treated group than pancreatic cancer group of mice. CONCLUSIONS: Data revealed that 5HT2A antagonist ameliorates pain associated with pancreatic cancer mice by HDAC inhibition and inflammatory cytokines. The result of investigation supports that modulation of 5HT2A receptor could be used clinically to protects neuropathic pain in pancreatic cancer.
Asunto(s)
Dolor en Cáncer , Neuralgia , Neoplasias Pancreáticas , Animales , Humanos , Ratones , Peso Corporal , Dolor en Cáncer/tratamiento farmacológico , Dolor en Cáncer/prevención & control , Citocinas , Modelos Animales de Enfermedad , Ratones Endogámicos BALB C , Neuralgia/tratamiento farmacológico , Neoplasias Pancreáticas/complicaciones , Receptores de Serotonina/metabolismoRESUMEN
The PWWP domain of hepatoma-derived growth factor-related protein 2 (HDGFRP2) recognizes methylated histones to initiate the recruitment of homologous recombination repair proteins to damaged silent genes. The combined depletion of HDGFRP2 and its paralog PSIP1 effectively impedes the onset and progression of diffuse intrinsic pontine glioma (DIPG). Here, we discovered varenicline and 4-(4-bromo-1H-pyrazol-3-yl) pyridine (BPP) as inhibitors of the HDGFRP2 PWWP domain through a fragment-based screening method. The complex crystal structures reveal that both Varenicline and BPP engage with the aromatic cage of the HDGFRP2 PWWP domain, albeit via unique binding mechanisms. Notably, BPP represents the first single-digit micromolar inhibitor of the HDGFRP2 PWWP domain with a high ligand efficiency. As a dual inhibitor targeting both HDGFRP2 and PSIP1 PWWP domains, BPP offers an exceptional foundation for further optimization into a chemical tool to dissect the synergetic function of HDGFRP2 and PSIP1 in DIPG pathogenesis.
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AIMS: Hepatocellular carcinoma (HCC) is the third leading cause of cancer death worldwide. In the present study, we evaluated SIRT4 expression levels in HCC specimens and investigated the relationships between SIRT4 expression levels, clinicopathological factors, and microvascular infiltration (MVI) in HCC. METHODS: The expression levels of SIRT4 in 108 HCC specimens were examined by immunohistochemical staining. MVI in HCC specimens was divided into three subtypes: M0, M1, and M2. Comprehensive bioinformatics analysis was carried out to demonstrate SIRT4's biological functions and expression-related prognostic value. RESULTS: The diffuse cytoplasmic expression pattern of SIRT4 was observed in all adjacent nonneoplastic liver tissues. The levels of SIRT4 were higher in HCC than in any other type of cancer and normal tissues. In addition, the expression levels of SIRT4 were significantly decreased in HCC tissues when MVI was M1 or M2 (P=0.003) but were not related to the overall clinical outcome. To explain MVI regulated by SIRT4, we also found that SIRT4 expression correlated with epithelial-mesenchymal transition (EMT) markers and CD4+ T/NK cells and downregulated cancer-associated fibroblast cells. Also, there was a significant relationship between MVI and degree of cell differentiation (P=0.003), tumor size (P<0.001), alpha fetoprotein (AFP) (P=0.001), alanine aminotransferase (ALT) (P=0.024), and γ-glutamyl transferase (γ-GT) (P=0.024). However, SIRT4 was not an independent prognostic marker of HCC. CONCLUSIONS: Our results demonstrated an association between SIRT4 expression levels, MVI, immune cell infiltration, and potential biological functions, including EMT in the progression of HCC.
RESUMEN
Stress granules (SGs) are membrane-less organelles (MLOs) or cytosolic compartments formed upon exposure to environmental cell stress-inducing stimuli. SGs are based on ribonucleoprotein complexes from a set of cytoplasmic proteins and mRNAs, blocked in translation due to stress cell-induced polysome disassembly. Post-translational modifications (PTMs) such as methylation, are involved in SG assembly, with the methylation writer PRMT1 and its reader TDRD3 colocalizing to SGs. However, the role of this writer-reader system in SG assembly remains unclear. Here, we found that PRMT1 methylates SG constituent RNA-binding proteins (RBPs) on their RGG motifs. Besides, we report that TDRD3, as a reader of asymmetric dimethylarginines, enhances RNA binding to recruit additional RNAs and RBPs, lowering the percolation threshold and promoting SG assembly. Our study enriches our understanding of the molecular mechanism of SG formation by elucidating the functions of PRMT1 and TDRD3. We anticipate that our study will provide a new perspective for comprehensively understanding the functions of PTMs in liquid-liquid phase separation driven condensate assembly.
RESUMEN
The formation of membrane-less organelles is driven by multivalent weak interactions while mediation of such interactions by small molecules remains an unparalleled challenge. Here, we uncovered a bivalent inhibitor that blocked the recruitment of TDRD3 by the two methylated arginines of G3BP1. Relative to the monovalent inhibitor, this bivalent inhibitor demonstrated an enhanced binding affinity to TDRD3 and capability to suppress the phase separation of methylated G3BP1, TDRD3, and RNAs, and in turn inhibit the stress granule growth in cells. Our result paves a new path to mediate multivalent interactions involved in SG assembly for potential combinational chemotherapy by bivalent inhibitors.
Asunto(s)
ADN Helicasas , ARN Helicasas , ADN Helicasas/metabolismo , ARN Helicasas/metabolismo , Proteínas de Unión a Poli-ADP-Ribosa/metabolismo , Proteínas con Motivos de Reconocimiento de ARN/metabolismo , Separación de Fases , Gránulos Citoplasmáticos/metabolismoRESUMEN
Purpose Patients have been severely suffered from cancer associated pain, and pancreatic cancer is the most severe form of cancer associated with pain. There are very few options available to manage it. The present report evaluated the effect of 5HT2A on pancreatic cancer associated pain. Methods Pancreatic cancer was induced by injecting SW 1,990 cells (~3×106 in a 20 µL suspension) into the pancreas and formed a 23-mm vesicle using an inoculator fitted with a 26-gauge needle in BALB/c-nu mice. Survival rate and body weight of the mice were observed. Pain behaviour testing was performed at the end of each week (third and fourth week) after surgery. Inflammatory mediators and HDAC 2 proteins were determined in the spinal tissue using quantitative real-time polymerase chain reaction. Results There was improvement in the survival rate and body weight in 5HT2A antagonist treated group than pancreatic cancer group of mice. Moreover, 5HT2A antagonist ameliorated the alteration in pain behaviour of pancreatic cancer mice. mRNA expression of HDAC2 and level of inflammatory cytokines were reduced in the spinal tissue of 5HT 2A antagonist treated group than pancreatic cancer group of mice. Conclusions Data revealed that 5HT2A antagonist ameliorates pain associated with pancreatic cancer mice by HDAC inhibition and inflammatory cytokines. The result of investigation supports that modulation of 5HT2A receptor could be used clinically to protects neuropathic pain in pancreatic cancer.