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1.
Nature ; 630(8016): 375-380, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38778112

RESUMEN

Ice surfaces are closely relevant to many physical and chemical properties, such as melting, freezing, friction, gas uptake and atmospheric reaction1-8. Despite extensive experimental and theoretical investigations9-17, the exact atomic structures of ice interfaces remain elusive owing to the vulnerable hydrogen-bonding network and the complicated premelting process. Here we realize atomic-resolution imaging of the basal (0001) surface structure of hexagonal water ice (ice Ih) by using qPlus-based cryogenic atomic force microscopy with a carbon monoxide-functionalized tip. We find that the crystalline ice-Ih surface consists of mixed Ih- and cubic (Ic)-stacking nanodomains, forming 19 × 19 periodic superstructures. Density functional theory reveals that this reconstructed surface is stabilized over the ideal ice surface mainly by minimizing the electrostatic repulsion between dangling OH bonds. Moreover, we observe that the ice surface gradually becomes disordered with increasing temperature (above 120 Kelvin), indicating the onset of the premelting process. The surface premelting occurs from the defective boundaries between the Ih and Ic domains and can be promoted by the formation of a planar local structure. These results put an end to the longstanding debate on ice surface structures and shed light on the molecular origin of ice premelting, which may lead to a paradigm shift in the understanding of ice physics and chemistry.

2.
Proc Natl Acad Sci U S A ; 121(26): e2320835121, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38900797

RESUMEN

Upper aerodigestive squamous cell carcinoma (UASCC) is a common and aggressive malignancy with few effective therapeutic options. Here, we investigate amino acid metabolism in this cancer, surprisingly noting that UASCC exhibits the highest methionine level across all human cancers, driven by its transporter LAT1. We show that LAT1 is also expressed at the highest level in UASCC, transcriptionally activated by UASCC-specific promoter and enhancers, which are directly coregulated by SCC master regulators TP63/KLF5/SREBF1. Unexpectedly, unbiased bioinformatic screen identifies EZH2 as the most significant target downstream of the LAT1-methionine pathway, directly linking methionine metabolism to epigenomic reprogramming. Importantly, this cascade is indispensable for the survival and proliferation of UASCC patient-derived tumor organoids. In addition, LAT1 expression is closely associated with cellular sensitivity to inhibition of the LAT1-methionine-EZH2 axis. Notably, this unique LAT1-methionine-EZH2 cascade can be targeted effectively by either pharmacological approaches or dietary intervention in vivo. In summary, this work maps a unique mechanistic cross talk between epigenomic reprogramming with methionine metabolism, establishes its biological significance in the biology of UASCC, and identifies a unique tumor-specific vulnerability which can be exploited both pharmacologically and dietarily.


Asunto(s)
Carcinoma de Células Escamosas , Regulación Neoplásica de la Expresión Génica , Transportador de Aminoácidos Neutros Grandes 1 , Metionina , Metionina/metabolismo , Humanos , Transportador de Aminoácidos Neutros Grandes 1/metabolismo , Transportador de Aminoácidos Neutros Grandes 1/genética , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patología , Proteína Potenciadora del Homólogo Zeste 2/metabolismo , Proteína Potenciadora del Homólogo Zeste 2/genética , Línea Celular Tumoral , Epigénesis Genética , Epigenómica/métodos , Neoplasias de Cabeza y Cuello/genética , Neoplasias de Cabeza y Cuello/metabolismo , Neoplasias de Cabeza y Cuello/patología , Ratones , Carcinoma de Células Escamosas de Cabeza y Cuello/genética , Carcinoma de Células Escamosas de Cabeza y Cuello/metabolismo , Carcinoma de Células Escamosas de Cabeza y Cuello/patología , Animales , Proliferación Celular , Factores de Transcripción de Tipo Kruppel/metabolismo , Factores de Transcripción de Tipo Kruppel/genética , Reprogramación Celular/genética
3.
Proc Natl Acad Sci U S A ; 121(27): e2402143121, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38923993

RESUMEN

The non-neural cholinergic system plays a critical role in regulating immune equilibrium and tissue homeostasis. While the expression of choline acetyltransferase (ChAT), the enzyme catalyzing acetylcholine biosynthesis, has been well documented in lymphocytes, its role in the myeloid compartment is less understood. Here, we identify a significant population of macrophages (Mϕs) expressing ChAT and synthesizing acetylcholine in the resolution phase of acute peritonitis. Using Chat-GFP reporter mice, we observed marked upregulation of ChAT in monocyte-derived small peritoneal Mϕs (SmPMs) in response to Toll-like receptor agonists and bacterial infections. These SmPMs, phenotypically and transcriptionally distinct from tissue-resident large peritoneal macrophages, up-regulated ChAT expression through a MyD88-dependent pathway involving MAPK signaling. Notably, this process was attenuated by the TRIF-dependent TLR signaling pathway, and our tests with a range of neurotransmitters and cytokines failed to induce a similar response. Functionally, Chat deficiency in Mϕs led to significantly decreased peritoneal acetylcholine levels, reduced efferocytosis of apoptotic neutrophils, and a delayed resolution of peritonitis, which were reversible with exogenous ACh supplementation. Intriguingly, despite B lymphocytes being a notable ChAT-expressing population within the peritoneal cavity, Chat deletion in B cells did not significantly alter the resolution process. Collectively, these findings underscore the crucial role of Mϕ-derived acetylcholine in the resolution of inflammation and highlight the importance of the non-neuronal cholinergic system in immune regulation.


Asunto(s)
Acetilcolina , Colina O-Acetiltransferasa , Macrófagos Peritoneales , Peritonitis , Animales , Colina O-Acetiltransferasa/metabolismo , Colina O-Acetiltransferasa/genética , Peritonitis/inmunología , Peritonitis/metabolismo , Ratones , Macrófagos Peritoneales/metabolismo , Macrófagos Peritoneales/inmunología , Acetilcolina/metabolismo , Factor 88 de Diferenciación Mieloide/metabolismo , Factor 88 de Diferenciación Mieloide/genética , Ratones Endogámicos C57BL , Transducción de Señal , Inflamación/metabolismo , Inflamación/patología , Linfocitos B/inmunología , Linfocitos B/metabolismo , Receptores Toll-Like/metabolismo , Fagocitosis , Macrófagos/metabolismo , Macrófagos/inmunología , Ratones Noqueados
4.
J Immunol ; 212(12): 1932-1944, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38709167

RESUMEN

IFN regulatory factor 7 (IRF7) exerts anti-infective effects by promoting the production of IFNs in various bacterial and viral infections, but its role in highly morbid and fatal Candida albicans infections is unknown. We unexpectedly found that Irf7 gene expression levels were significantly upregulated in tissues or cells after C. albicans infection in humans and mice and that IRF7 actually exacerbates C. albicans infection in mice independent of its classical function in inducing IFNs production. Compared to controls, Irf7-/- mice showed stronger phagocytosis of fungus, upregulation of C-type lectin receptor CD209 expression, and enhanced P53-AMPK-mTOR-mediated autophagic signaling in macrophages after C. albicans infection. The administration of the CD209-neutralizing Ab significantly hindered the phagocytosis of Irf7-/- mouse macrophages, whereas the inhibition of p53 or autophagy impaired the killing function of these macrophages. Thus, IRF7 exacerbates C. albicans infection by compromising the phagocytosis and killing capacity of macrophages via regulating CD209 expression and p53-AMPK-mTOR-mediated autophagy, respectively. This finding reveals a novel function of IRF7 independent of its canonical IFNs production and its unexpected role in enhancing fungal infections, thus providing more specific and effective targets for antifungal therapy.


Asunto(s)
Autofagia , Candida albicans , Candidiasis , Factor 7 Regulador del Interferón , Lectinas Tipo C , Macrófagos , Ratones Noqueados , Fagocitosis , Receptores de Superficie Celular , Serina-Treonina Quinasas TOR , Animales , Ratones , Fagocitosis/inmunología , Autofagia/inmunología , Lectinas Tipo C/genética , Lectinas Tipo C/metabolismo , Candidiasis/inmunología , Candida albicans/inmunología , Candida albicans/fisiología , Factor 7 Regulador del Interferón/genética , Factor 7 Regulador del Interferón/metabolismo , Factor 7 Regulador del Interferón/inmunología , Macrófagos/inmunología , Humanos , Receptores de Superficie Celular/genética , Receptores de Superficie Celular/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Proteína p53 Supresora de Tumor/genética , Ratones Endogámicos C57BL , Moléculas de Adhesión Celular/genética , Moléculas de Adhesión Celular/metabolismo , Transducción de Señal/inmunología
5.
J Neurosci ; 44(32)2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-38977300

RESUMEN

Activity of central amygdala (CeA) PKCδ expressing neurons has been linked to appetite regulation, anxiety-like behaviors, pain sensitivity, and addiction-related behaviors. Studies of the role that CeA PKCδ+ neurons play in these behaviors have largely been carried out in mice, and genetic tools that would allow selective manipulation of PKCδ+ cells in rats have been lacking. Here, we used a CRISPR/Cas9 strategy to generate a transgenic Prkcd-cre knock-in rat and characterized this model using anatomical, electrophysiological, and behavioral approaches in both sexes. In the CeA, Cre was selectively expressed in PKCδ+ cells. Anterograde projections of PKCδ+ neurons to cortical regions, subcortical regions, several hypothalamic nuclei, the amygdala complex, and midbrain dopaminergic regions were largely consistent with published mouse data. In a behavioral screen, we found no differences between Cre+ rats and Cre- wild-type littermates. Optogenetic stimulation of CeA PKCδ+ neurons in a palatable food intake assay resulted in an increased latency to first feeding and decreased total food intake, once again replicating published mouse findings. Lastly, using a real-time place preference task, we found that stimulation of PKCδ+ neurons promoted aversion, without affecting locomotor activity. Collectively, these findings establish the novel Prkcd-Cre rat line as a valuable tool that complements available mouse lines for investigating the functional role of PKCδ+ neurons.


Asunto(s)
Proteína Quinasa C-delta , Animales , Proteína Quinasa C-delta/genética , Proteína Quinasa C-delta/metabolismo , Ratas , Masculino , Femenino , Ratas Transgénicas , Neuronas/fisiología , Núcleo Amigdalino Central/fisiología , Integrasas/genética , Optogenética/métodos , Ratas Sprague-Dawley
6.
J Biol Chem ; 300(7): 107468, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38876301

RESUMEN

The nucleosome remodeling and deacetylase (NuRD) complex plays a pivotal role in chromatin regulation and transcriptional repression. In mice, methyl-CpG binding domain 3 isoform C (MBD3C) interacts specifically with the histone H3 binding protein WD repeat-containing protein 5 (WDR5) and forms the WDR5-MBD3C/Norde complex. Despite the functional significance of this interaction on embryonic stem cell gene regulation, the molecular mechanism underlying MBD3C recognition by WDR5 remains elusive. Here, we determined the crystal structure of WDR5 in complex with the peptide (residues 40-51) derived from the MBD3C protein at a resolution of 1.9 Å. Structural analysis revealed that MBD3C utilizes a unique binding mode to interact with WDR5, wherein MBD3C Arg43 and Phe47 are involved in recognizing the WDR5-interacting (WIN) site and Tyr191-related B site on the small surface of WDR5, respectively. Notably, the binding induces a ∼91° rotation of WDR5 Tyr191, generating the hydrophobic B site. Furthermore, mutation experiments combined with isothermal titration calorimetry (ITC) assays confirmed the importance of both Arg43 and Phe47 in mediating WDR5 binding affinity. By determining structures of various peptides bound to WDR5, we demonstrated that the WDR5 WIN site and B site can be concurrently recognized by WIN motif peptides containing ''Arg-Cies/Ser-Arg-Val-Phe'' consensus sequence. Overall, this study reveals the structural basis for the formation of the WDR5-MBD3C subcomplex and provides new insights into the recognition mode of WDR5 for the WIN motif. Moreover, these findings shed light on structural-based designs of WDR5-targeted anti-cancer small molecule inhibitors or peptide-mimic drugs.


Asunto(s)
Unión Proteica , Ratones , Animales , Cristalografía por Rayos X , Secuencias de Aminoácidos , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Péptidos y Proteínas de Señalización Intracelular/química , Péptidos y Proteínas de Señalización Intracelular/genética , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/genética , Humanos , Sitios de Unión
7.
Circulation ; 149(18): 1435-1456, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38357822

RESUMEN

BACKGROUND: A main obstacle in current valvular heart disease research is the lack of high-quality homogeneous functional heart valve cells. Human induced pluripotent stem cells (hiPSCs)-derived heart valve cells may help with this dilemma. However, there are no well-established protocols to induce hiPSCs to differentiate into functional heart valve cells, and the networks that mediate the differentiation have not been fully elucidated. METHODS: To generate heart valve cells from hiPSCs, we sequentially activated the Wnt, BMP4, VEGF (vascular endothelial growth factor), and NFATc1 signaling pathways using CHIR-99021, BMP4, VEGF-165, and forskolin, respectively. The transcriptional and functional similarity of hiPSC-derived heart valve cells compared with primary heart valve cells were characterized. Longitudinal single-cell RNA sequencing was used to uncover the trajectory, switch genes, pathways, and transcription factors of the differentiation. RESULTS: An efficient protocol was developed to induce hiPSCs to differentiate into functional hiPSC-derived valve endothelial-like cells and hiPSC-derived valve interstitial-like cells. After 6-day differentiation and CD144 magnetic bead sorting, ≈70% CD144+ cells and 30% CD144- cells were obtained. On the basis of single-cell RNA sequencing data, the CD144+ cells and CD144- cells were found to be highly similar to primary heart valve endothelial cells and primary heart valve interstitial cells in gene expression profile. Furthermore, CD144+ cells had the typical function of primary heart valve endothelial cells, including tube formation, uptake of low-density lipoprotein, generation of endothelial nitric oxide synthase, and response to shear stress. Meanwhile, CD144- cells could secret collagen and matrix metalloproteinases, and differentiate into osteogenic or adipogenic lineages like primary heart valve interstitial cells. Therefore, we identified CD144+ cells and CD144- cells as hiPSC-derived valve endothelial-like cells and hiPSC-derived valve interstitial-like cells, respectively. Using single-cell RNA sequencing analysis, we demonstrated that the trajectory of heart valve cell differentiation was consistent with embryonic valve development. We identified the main switch genes (NOTCH1, HEY1, and MEF2C), signaling pathways (TGF-ß, Wnt, and NOTCH), and transcription factors (MSX1, SP5, and MECOM) that mediated the differentiation. Finally, we found that hiPSC-derived valve interstitial-like cells might derive from hiPSC-derived valve endothelial-like cells undergoing endocardial-mesenchymal transition. CONCLUSIONS: In summary, this is the first study to report an efficient strategy to generate functional hiPSC-derived valve endothelial-like cells and hiPSC-derived valve interstitial-like cells from hiPSCs, as well as to elucidate the differentiation trajectory and transcriptional dynamics of hiPSCs differentiated into heart valve cells.


Asunto(s)
Diferenciación Celular , Válvulas Cardíacas , Células Madre Pluripotentes Inducidas , Humanos , Células Madre Pluripotentes Inducidas/citología , Células Madre Pluripotentes Inducidas/metabolismo , Válvulas Cardíacas/citología , Válvulas Cardíacas/metabolismo , Células Cultivadas , Células Endoteliales/metabolismo , Células Endoteliales/citología , Transducción de Señal
8.
Bioinformatics ; 40(6)2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38897656

RESUMEN

MOTIVATION: Predicting protein-ligand binding affinity is crucial in new drug discovery and development. However, most existing models rely on acquiring 3D structures of elusive proteins. Combining amino acid sequences with ligand sequences and better highlighting active sites are also significant challenges. RESULTS: We propose an innovative neural network model called DEAttentionDTA, based on dynamic word embeddings and a self-attention mechanism, for predicting protein-ligand binding affinity. DEAttentionDTA takes the 1D sequence information of proteins as input, including the global sequence features of amino acids, local features of the active pocket site, and linear representation information of the ligand molecule in the SMILE format. These three linear sequences are fed into a dynamic word-embedding layer based on a 1D convolutional neural network for embedding encoding and are correlated through a self-attention mechanism. The output affinity prediction values are generated using a linear layer. We compared DEAttentionDTA with various mainstream tools and achieved significantly superior results on the same dataset. We then assessed the performance of this model in the p38 protein family. AVAILABILITY AND IMPLEMENTATION: The resource codes are available at https://github.com/whatamazing1/DEAttentionDTA.


Asunto(s)
Redes Neurales de la Computación , Unión Proteica , Proteínas , Ligandos , Proteínas/química , Proteínas/metabolismo , Secuencia de Aminoácidos , Programas Informáticos , Sitios de Unión , Biología Computacional/métodos , Bases de Datos de Proteínas
9.
J Pathol ; 263(1): 74-88, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38411274

RESUMEN

Fascin actin-bundling protein 1 (Fascin) is highly expressed in a variety of cancers, including esophageal squamous cell carcinoma (ESCC), working as an important oncogenic protein and promoting the migration and invasion of cancer cells by bundling F-actin to facilitate the formation of filopodia and invadopodia. However, it is not clear how exactly the function of Fascin is regulated by acetylation in cancer cells. Here, in ESCC cells, the histone acetyltransferase KAT8 catalyzed Fascin lysine 41 (K41) acetylation, to inhibit Fascin-mediated F-actin bundling and the formation of filopodia and invadopodia. Furthermore, NAD-dependent protein deacetylase sirtuin (SIRT) 7-mediated deacetylation of Fascin-K41 enhances the formation of filopodia and invadopodia, which promotes the migration and invasion of ESCC cells. Clinically, the analysis of cancer and adjacent tissue samples from patients with ESCC showed that Fascin-K41 acetylation was lower in the cancer tissue of patients with lymph node metastasis than in that of patients without lymph node metastasis, and low levels of Fascin-K41 acetylation were associated with a poorer prognosis in patients with ESCC. Importantly, K41 acetylation significantly blocked NP-G2-044, one of the Fascin inhibitors currently being clinically evaluated, suggesting that NP-G2-044 may be more suitable for patients with low levels of Fascin-K41 acetylation, but not suitable for patients with high levels of Fascin-K41 acetylation. © 2024 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Asunto(s)
Proteínas Portadoras , Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Proteínas de Microfilamentos , Sirtuinas , Humanos , Acetilación , Actinas/metabolismo , Línea Celular Tumoral , Neoplasias Esofágicas/patología , Histona Acetiltransferasas/metabolismo , Metástasis Linfática , Sirtuinas/metabolismo
10.
Cell Mol Life Sci ; 81(1): 280, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38918243

RESUMEN

Candida albicans is among the most prevalent invasive fungal pathogens for immunocompromised individuals and novel therapeutic approaches that involve immune response modulation are imperative. Absent in melanoma 2 (AIM2), a pattern recognition receptor for DNA sensing, is well recognized for its involvement in inflammasome formation and its crucial role in safeguarding the host against various pathogenic infections. However, the role of AIM2 in host defense against C. albicans infection remains uncertain. This study reveals that the gene expression of AIM2 is induced in human and mouse innate immune cells or tissues after C. albicans infection. Furthermore, compared to their wild-type (WT) counterparts, Aim2-/- mice surprisingly exhibit resistance to C. albicans infection, along with reduced inflammation in the kidneys post-infection. The resistance of Aim2-/- mice to C. albicans infection is not reliant on inflammasome or type I interferon production. Instead, Aim2-/- mice display lower levels of apoptosis in kidney tissues following infection than WT mice. The deficiency of AIM2 in macrophages, but not in dendritic cells, results in a phenocopy of the resistance observed in Aim2-/- mice against C. albican infection. The treatment of Clodronate Liposome, a reagent that depletes macrophages, also shows the critical role of macrophages in host defense against C. albican infection in Aim2-/- mice. Furthermore, the reduction in apoptosis is observed in Aim2-/- mouse macrophages following infection or treatment of DNA from C. albicans in comparison with controls. Additionally, higher levels of AKT activation are observed in Aim2-/- mice, and treatment with an AKT inhibitor reverses the host resistance to C. albicans infection. The findings collectively demonstrate that AIM2 exerts a negative regulatory effect on AKT activation and enhances macrophage apoptosis, ultimately compromising host defense against C. albicans infection. This suggests that AIM2 and AKT may represent promising therapeutic targets for the management of fungal infections.


Asunto(s)
Apoptosis , Candida albicans , Candidiasis , Proteínas de Unión al ADN , Macrófagos , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas Proto-Oncogénicas c-akt , Transducción de Señal , Animales , Macrófagos/metabolismo , Macrófagos/inmunología , Macrófagos/microbiología , Candidiasis/inmunología , Candidiasis/microbiología , Candidiasis/metabolismo , Candidiasis/patología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratones , Humanos , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ADN/genética , Inflamasomas/metabolismo , Inmunidad Innata , Riñón/patología , Riñón/metabolismo , Riñón/microbiología
11.
Drug Resist Updat ; 73: 101052, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38262246

RESUMEN

AIMS: This investigation aims to elucidate the mechanism underlying sorafenib-induced ferroptosis in hepatocellular carcinoma (HCC). METHODS: The role of dual specificity phosphatase 4 (DUSP4) in sorafenib-treated HCC was investigated using comprehensive assessments both in vitro and in vivo, including Western blotting, qRT-PCR, cell viability assay, lipid reactive oxygen species (ROS) assay, immunohistochemistry, and xenograft tumor mouse model. Additionally, label-free quantitative proteomics was employed to identify potential proteins associated with DUSP4. RESULTS: Our study revealed that suppression of DUSP4 expression heightens the susceptibility of HCC cells to ferroptosis inducers, specifically sorafenib and erastin, in both in vitro and in vivo settings. Furthermore, we identified DUSP4-mediated regulation of key ferroptosis-related markers, such as ferritin light chain (FTL) and ferritin heavy chain 1 (FTH1). Notably, label-free quantitative proteomics unveiled the phosphorylation of threonine residue T148 on YTH Domain Containing 1 (YTHDC1) by DUSP4. Further investigations unraveled that YTHDC1, functioning as an mRNA nuclear export regulator, is a direct target of DUSP4, orchestrating the subcellular localization of FTL and FTH1 mRNAs. Significantly, our study highlights a strong correlation between elevated DUSP4 expression and sorafenib resistance in HCC. CONCLUSIONS: Our findings introduce DUSP4 as a negative regulator of sorafenib-induced ferroptosis. This discovery opens new avenues for the development of ferroptosis-based therapeutic strategies tailored for HCC treatment.


Asunto(s)
Carcinoma Hepatocelular , Fosfatasas de Especificidad Dual , Ferroptosis , Neoplasias Hepáticas , Animales , Humanos , Ratones , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/genética , Línea Celular Tumoral , Ferroptosis/genética , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/genética , Monoéster Fosfórico Hidrolasas/uso terapéutico , Sorafenib/farmacología , Sorafenib/uso terapéutico , Fosfatasas de Especificidad Dual/genética , Fosfatasas de Especificidad Dual/metabolismo , Fosfatasas de la Proteína Quinasa Activada por Mitógenos/genética , Fosfatasas de la Proteína Quinasa Activada por Mitógenos/metabolismo
12.
Nano Lett ; 24(4): 1197-1204, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38227967

RESUMEN

Electrocatalytic reduction of nitrate to ammonia (NO3RR) is gaining attention for low carbon emissions and environmental protection. However, low ammonia production rate and poor selectivity have remained major challenges in this multi-proton coupling process. Herein, we report a facile strategy toward a novel Fe-based hybrid structure composed of Fe single atoms and Fe3C atomic clusters that demonstrates outstanding performance for synergistic electrocatalytic NO3RR. By operando synchrotron Fourier transform infrared spectroscopy and theoretical computation, we clarify that Fe single atoms serve as the active site for NO3RR, while Fe3C clusters facilitate H2O dissociation to provide protons (*H) for continued hydrogenation reactions. As a result, the Fe-based electrocatalyst exhibits ammonia Faradaic efficiency of nearly 100%, with a corresponding production rate of 24768 µg h-1 cm-2 at -0.4 V vs RHE, exceeding most reported metal-based catalysts. This research provides valuable guidance toward multi-step reactions.

13.
Nano Lett ; 24(25): 7732-7740, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38869233

RESUMEN

Rechargeable lithium-ion batteries are integral to contemporary energy storage, yet current anode material systems struggle to meet the increasing demand for extended range capabilities. This work introduces a novel composite anode material composed of one-dimensional 2H-phase tin disulfide (SnS2) nanoribbons enclosed within cavities of single-walled carbon nanotubes (SnS2@SWCNTs), achieved through precise atomic engineering. Employing aberration-corrected transmission electron microscopy, we precisely elucidated the crystal structure of SnS2 within the confines of the SWCNTs. This deliberate design effectively addresses the inherent limitations of SnS2 as a lithium-ion anode material, including its low electrical conductivity, considerable volume expansion effects, and unstable solid electrolyte interface membrane. Testing confirmed that SnS2 transforms into the Li5Sn2 alloy phase after full lithiation and back to SnS2 after delithiation, showing excellent reversibility. The composite also benefits from edge effects, improving lithium storage through stronger binding and lower migration barriers, which were supported by calculations. This pioneering work advances high-performance anode materials for applications.

14.
Diabetologia ; 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39037604

RESUMEN

AIMS/HYPOTHESIS: The relationship between metabolic dysfunction-associated steatotic liver disease (MASLD) and type 2 diabetes mellitus, insulin resistance and the metabolic syndrome is well established. While zinc finger BED-type containing 3 (ZBED3) has been linked to type 2 diabetes mellitus and the metabolic syndrome, its role in MASLD remains unclear. In this study, we aimed to investigate the function of ZBED3 in the context of MASLD. METHODS: Expression levels of ZBED3 were assessed in individuals with MASLD, as well as in cellular and animal models of MASLD. In vitro and in vivo analyses were conducted using a cellular model of MASLD induced by NEFA and an animal model of MASLD induced by a high-fat diet (HFD), respectively, to investigate the role of ZBED3 in MASLD. ZBED3 expression was increased by lentiviral infection or tail-vein injection of adeno-associated virus. RNA-seq and bioinformatics analysis were employed to examine the pathways through which ZBED3 modulates lipid accumulation. Findings from these next-generation transcriptome sequencing studies indicated that ZBED3 controls SREBP1c (also known as SREBF1; a gene involved in fatty acid de novo synthesis); thus, co-immunoprecipitation and LC-MS/MS were utilised to investigate the molecular mechanisms by which ZBED3 regulates the sterol regulatory element binding protein 1c (SREBP1c). RESULTS: In this study, we found that ZBED3 was significantly upregulated in the liver of individuals with MASLD and in MASLD animal models. ZBED3 overexpression promoted NEFA-induced triglyceride accumulation in hepatocytes in vitro. Furthermore, the hepatocyte-specific overexpression of Zbed3 promoted hepatic steatosis. Conversely, the hepatocyte-specific knockout of Zbed3 resulted in resistance of HFD-induced hepatic steatosis. Mechanistically, ZBED3 interacts directly with polypyrimidine tract-binding protein 1 (PTBP1) and affects its binding to the SREBP1c mRNA precursor to regulate SREBP1c mRNA stability and alternative splicing. CONCLUSIONS/INTERPRETATION: This study indicates that ZBED3 promotes hepatic steatosis and serves as a critical regulator of the progression of MASLD. DATA AVAILABILITY: RNA-seq data have been deposited in the NCBI Gene Expression Omnibus ( www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE231875 ). MS proteomics data have been deposited to the ProteomeXchange Consortium via the iProX partner repository ( https://proteomecentral.proteomexchange.org/cgi/GetDataset?ID=PXD041743 ).

15.
Br J Cancer ; 130(3): 450-456, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38110665

RESUMEN

BACKGROUND: Cadonilimab is a bispecific antibody that simultaneously targets programmed cell death receptor-1 and cytotoxic T lymphocyte-associated antigen-4. This study aimed to assess the safety and efficacy of cadonilimab plus anlotinib for the first-line treatment of advanced non-small cell lung cancer (NSCLC) without sensitizing EGFR/ALK/ROS1 mutations. METHODS: Patients received cadonilimab 15 mg/kg and 10 mg/kg every three weeks (Q3W) plus anlotinib at doses of 10 or 12 mg once daily for two weeks on a one-week-off schedule. The primary endpoints included safety and objective response rate (ORR). RESULTS: Sixty-nine treatment-naïve patients received cadonilimab 15 mg/kg Q3W combination (n = 49) and 10 mg/kg Q3W combination (n = 20). Treatment-related adverse events (TRAEs) were reported in 48 (98.0%) and 19 (95.0%) patients, with grade ≥3 TRAEs occurring in 29 (59.2%) and five (25.0%) patients, respectively. TRAEs leading to cadonilimab discontinuation occurred in eight (16.3%) and one (5.0%) patients in the cadonilimab 15 mg/kg Q3W and 10 mg/kg Q3W dosing groups. The confirmed ORRs were 51.0% (25/49) and 60.0% (12/20) accordingly. CONCLUSIONS: Cadonilimab 10 mg/kg Q3W plus anlotinib showed manageable safety and promising efficacy as a first-line chemo-free treatment for advanced NSCLC. GOV IDENTIFIER: NCT04646330.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Indoles , Neoplasias Pulmonares , Quinolinas , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Antígeno CTLA-4 , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Receptor de Muerte Celular Programada 1/uso terapéutico , Proteínas Tirosina Quinasas , Proteínas Proto-Oncogénicas
16.
Anal Chem ; 96(5): 2217-2226, 2024 02 06.
Artículo en Inglés | MEDLINE | ID: mdl-38262909

RESUMEN

Circulating tumor cells (CTCs) have emerged as powerful biomarkers for diagnosis of prostate cancer. However, the effective identification and concurrently accurate imaging of CTCs for early screening of prostate cancer have been rarely explored. Herein, we reported a multifunctional gold nanoprobe-based thermophoretic assay for simultaneous specific distinguishing of prostate cancer CTCs and sensitive imaging of intracellular microRNA (miR-21), achieving the rapid and precise detection of prostate cancer. The multifunctional gold nanoprobe (GNP-DNA/Ab) was modified by two types of prostate-specific antibodies, anti-PSMA and anti-EpCAM, which could effectively recognize the targeting CTCs, and meanwhile linked double-stranded DNA for further visually imaging intracellular miR-21. Upon the specific internalization of GNP-DNA/Ab by PC-3 cells, target aberrant miR-21 could displace the signal strand to recover the fluorescence signal for sensitive detection at the single-cell level, achieving single PC-3 cell imaging benefiting from the thermophoresis-mediated signal amplification procedure. Taking advantage of the sensitive miR-21 imaging performance, GNP-DNA/Ab could be employed to discriminate the PC-3 and Jurkat cells because of the different expression levels of miR-21. Notably, PC-3 cells were efficiently recognized from white blood cells, exhibiting promising potential for the early diagnosis of prostate cancer. Furthermore, GNP-DNA/Ab possessed good biocompatibility and stability. Therefore, this work provides a great tool for aberrant miRNA-related detection and specific discrimination of CTCs, achieving the early and accurate diagnosis of prostate cancer.


Asunto(s)
MicroARNs , Células Neoplásicas Circulantes , Neoplasias de la Próstata , Masculino , Humanos , Células Neoplásicas Circulantes/patología , Oro , Neoplasias de la Próstata/patología , ADN
17.
Anal Chem ; 96(29): 11832-11844, 2024 07 23.
Artículo en Inglés | MEDLINE | ID: mdl-38979898

RESUMEN

An effective tool to assess embryo quality in the assisted reproduction clinical practice will enhance successful implantation rates and mitigate high risks of multiple pregnancies. Potential biomarkers secreted into culture medium (CM) during embryo development enable rapid and noninvasive methods of assessing embryo quality. However, small volumes, low biomolecule concentrations, and impurity interference collectively preclude the identification of quality-related biomarkers in single blastocyst CM. Here, we developed a noninvasive trace multiomics approach to screen for potential markers in individual human blastocyst CM. We collected 84 CM samples and divided them into high-quality (HQ) and low-quality (LQ) groups. We evaluated the differentially expressed proteins (DEPs) and metabolites (DEMs) in HQ and LQ CM. A total of 504 proteins and 189 metabolites were detected in individual blastocyst CM. Moreover, 9 DEPs and 32 DEMs were identified in different quality embryo CM. We also categorized HQ embryos into positive implantation (PI) and negative implantation (NI) groups based on ultrasound findings on day 28. We identified 41 DEPs and 4 DEMs associated with clinical implantation outcomes in morphologically HQ embryos using a multiomics analysis approach. This study provides a noninvasive multiomics analysis technique and identifies potential biomarkers for clinical embryo developmental quality assessment.


Asunto(s)
Biomarcadores , Medios de Cultivo , Metabolómica , Proteómica , Humanos , Biomarcadores/metabolismo , Biomarcadores/análisis , Proteómica/métodos , Metabolómica/métodos , Medios de Cultivo/química , Medios de Cultivo/metabolismo , Blastocisto/metabolismo , Blastocisto/citología , Técnicas de Cultivo de Embriones , Embrión de Mamíferos/metabolismo , Multiómica
18.
Anal Chem ; 96(17): 6692-6699, 2024 04 30.
Artículo en Inglés | MEDLINE | ID: mdl-38632948

RESUMEN

The antibodies in the natural biological world utilize bivalency/multivalency to achieve a higher affinity for antigen capture. However, mimicking this mechanism on the electrochemical sensing interface and enhancing biological affinity through precise spatial arrangement of bivalent aptamer probes still pose a challenge. In this study, we have developed a novel self-assembly layer (SAM) incorporating triblock polyA DNA to enable accurate organization of the aptamer probes on the interface, constructing a "lock-and-key-like" proximity hybridization assay (PHA) biosensor. The polyA fragment acts as an anchoring block with a strong affinity for the gold surface. Importantly, it connects the two DNA probes, facilitating one-to-one spatial proximity and enabling a controllable surface arrangement. By precisely adjusting the length of the polyA fragment, we can tailor the distance between the probes to match the molecular dimensions of the target protein. This design effectively enhances the affinity of the aptamers. Notably, our biosensor demonstrates exceptional specificity and sensitivity in detecting PDGF-BB, as confirmed through successful validation using human serum samples. Overall, our biosensor presents a novel and versatile interface for proximity assays, offering a significantly improved surface arrangement and detection performance.


Asunto(s)
Aptámeros de Nucleótidos , Becaplermina , Técnicas Biosensibles , Hibridación de Ácido Nucleico , Poli A , Técnicas Biosensibles/métodos , Humanos , Aptámeros de Nucleótidos/química , Becaplermina/sangre , Poli A/química , Oro/química , Sondas de ADN/química
19.
Biochem Biophys Res Commun ; 727: 150307, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-38917618

RESUMEN

The testis-specific histone variant H3T plays a crucial role in chromatin reorganization during spermatogenesis by destabilizing nucleosomes. However, the structure basis for the nucleosome instability driven by H3T is not fully understand. In this study, we determinate the crystal structure of H3T-H4 in complex with histone chaperone ASF1a at 2.8 Å resolution. Our findings reveal that H3T-H4 binds ASF1a similarly to the conventional H3.1-H4 complex. However, significant structural differences are observed in the H3 α1 helix, the N- and C-terminal region of α2, and N-terminal region of L2. These differences are driven by H3T-specific residues, particularly Val111. Unlike the smaller Ala111 in H3.1, we find that bulkier residue Val111 fits well within the ASF1-H3T-H4 complex, but is difficult to arrange in nucleosome structure. Given that H3.1-Ala111/H3T-Val111 is located at the DNA binding and tetramerization interface of H3-H4, it is likely that Ala111Val substitution will lead to the instability of the corresponding area in nucleosome, contributing to instability of H3T-containing nucleosome. These structural findings may elucidate the role of H3T in chromatin reorganization during spermatogenesis.


Asunto(s)
Histonas , Nucleosomas , Nucleosomas/metabolismo , Nucleosomas/química , Histonas/metabolismo , Histonas/química , Histonas/genética , Humanos , Modelos Moleculares , Chaperonas Moleculares/metabolismo , Chaperonas Moleculares/química , Chaperonas Moleculares/genética , Cristalografía por Rayos X , Unión Proteica , Conformación Proteica , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/genética
20.
BMC Med ; 22(1): 172, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38650037

RESUMEN

BACKGROUND: Lenvatinib is widely used in treatment of unresectable hepatocellular carcinoma (uHCC), but the benefit of its combination with immunotherapy needs to be verified. This study evaluated the efficacy and safety of tislelizumab plus lenvatinib in systemic treatment-naïve patients with uHCC. METHODS: In this multicenter, single-arm, phase 2 study, systemic treatment-naïve patients with uHCC received tislelizumab 200 mg every three weeks plus lenvatinib (bodyweight ≥ 60 kg: 12 mg; < 60 kg: 8 mg; once daily). Dose-limiting toxicities (DLTs) were evaluated in safety run-in phase to determine whether to enter the expansion phase. The primary endpoint was objective response rate (ORR) assessed by independent review committee (IRC) per Response Evaluation Criteria in Solid Tumors, version 1.1 (RECIST v1.1). Based on Simon's two-stage design, > 6 responders were needed in stage 1 (n = 30) to continue the study, and ≥ 18 responders were needed by the end of stage 2 (n = 60) to demonstrate statistical superiority to a historical control of lenvatinib monotherapy. RESULTS: Sixty-four patients were enrolled. No DLTs were reported. The study achieved statistical superiority (p = 0.0003) with 23 responders assessed by IRC per RECIST v1.1 in the first 60 patients of the efficacy evaluable analysis set (n = 62). After a median follow-up of 15.7 months, confirmed ORR and disease control rate were 38.7% (24/62, 95% confidence interval [CI], 26.6-51.9) and 90.3% (56/62, 95% CI, 80.1-96.4), respectively. Median progression-free survival was 8.2 months (95% CI, 6.8-not evaluable). Overall survival rate at 12 months was 88.6% (95% CI, 77.7-94.4). Grade ≥ 3 treatment-related adverse events occurred in 18 (28.1%) patients. CONCLUSIONS: Tislelizumab plus lenvatinib demonstrated promising antitumor activity with favourable tolerability as first-line therapy for patients with uHCC. TRIAL REGISTRATION: ClinicalTrials.gov (NCT04401800).


Asunto(s)
Anticuerpos Monoclonales Humanizados , Carcinoma Hepatocelular , Neoplasias Hepáticas , Compuestos de Fenilurea , Quinolinas , Humanos , Carcinoma Hepatocelular/tratamiento farmacológico , Quinolinas/uso terapéutico , Quinolinas/efectos adversos , Quinolinas/administración & dosificación , Masculino , Neoplasias Hepáticas/tratamiento farmacológico , Compuestos de Fenilurea/uso terapéutico , Compuestos de Fenilurea/efectos adversos , Compuestos de Fenilurea/administración & dosificación , Femenino , Persona de Mediana Edad , Anciano , Anticuerpos Monoclonales Humanizados/uso terapéutico , Anticuerpos Monoclonales Humanizados/efectos adversos , Anticuerpos Monoclonales Humanizados/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Resultado del Tratamiento , Adulto
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