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1.
Cell ; 161(5): 1152-1163, 2015 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-25981666

RESUMEN

Cells adapt to temperature shifts by adjusting levels of lipid desaturation and membrane fluidity. This fundamental process occurs in nearly all forms of life, but its mechanism in eukaryotes is unknown. We discovered that the evolutionarily conserved Caenorhabditis elegans gene acdh-11 (acyl-CoA dehydrogenase [ACDH]) facilitates heat adaptation by regulating the lipid desaturase FAT-7. Human ACDH deficiency causes the most common inherited disorders of fatty acid oxidation, with syndromes that are exacerbated by hyperthermia. Heat upregulates acdh-11 expression to decrease fat-7 expression. We solved the high-resolution crystal structure of ACDH-11 and established the molecular basis of its selective and high-affinity binding to C11/C12-chain fatty acids. ACDH-11 sequesters C11/C12-chain fatty acids and prevents these fatty acids from activating nuclear hormone receptors and driving fat-7 expression. Thus, the ACDH-11 pathway drives heat adaptation by linking temperature shifts to regulation of lipid desaturase levels and membrane fluidity via an unprecedented mode of fatty acid signaling.


Asunto(s)
Acil-CoA Deshidrogenasa/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/fisiología , Ácidos Grasos/metabolismo , Acil-CoA Deshidrogenasa/química , Adaptación Fisiológica , Secuencia de Aminoácidos , Animales , Proteínas de Caenorhabditis elegans/química , Calor , Modelos Moleculares , Datos de Secuencia Molecular , Alineación de Secuencia
2.
Nat Immunol ; 18(11): 1207-1217, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28892469

RESUMEN

The tumor microenvironment confers profound resistance to anti-cancer immunotherapy. By targeting LIGHT, a member of the TNF superfamily of cytokines, to tumor vessels via a vascular targeting peptide (VTP), we developed a reagent with the dual ability to modulate the angiogenic vasculature and to induce tertiary lymphoid structures (TLSs). LIGHT-VTP triggered the influx of endogenous T cells into autochthonous or syngeneic tumors, which are resistant to immunotherapy. LIGHT-VTP in combination with checkpoint inhibition generated a large number of intratumoral effector and memory T cells with ensuing survival benefits, while the addition of anti-tumor vaccination achieved maximal therapeutic efficacy. Thus, the combination treatments stimulated the trafficking of pre-existing endogenous effector T cells as well as their intratumoral activation and were more successful than current immunotherapies, which fail due to tumor-intrinsic resistance mechanisms.


Asunto(s)
Inmunoterapia/métodos , Linfocitos/inmunología , Neoplasias/terapia , Neovascularización Patológica/terapia , Microambiente Tumoral/inmunología , Secuencia de Aminoácidos , Animales , Vacunas contra el Cáncer/administración & dosificación , Vacunas contra el Cáncer/farmacología , Resistencia a Antineoplásicos/inmunología , Quimioterapia Combinada , Linfocitos/metabolismo , Ratones Endogámicos C3H , Ratones Transgénicos , Neoplasias/irrigación sanguínea , Neoplasias/inmunología , Neovascularización Patológica/inmunología , Péptidos/administración & dosificación , Péptidos/genética , Péptidos/farmacología , Análisis de Supervivencia , Linfocitos T/efectos de los fármacos , Linfocitos T/inmunología , Linfocitos T/metabolismo , Resultado del Tratamiento , Miembro 14 de la Superfamilia de Ligandos de Factores de Necrosis Tumoral/química , Miembro 14 de la Superfamilia de Ligandos de Factores de Necrosis Tumoral/genética
3.
Nano Lett ; 24(33): 10090-10097, 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39106977

RESUMEN

Metasurfaces allow light to be manipulated at the nanoscale. Integrating metasurfaces with transition metal dichalcogenide monolayers provides additional functionality to ultrathin optics, including tunable optical properties with enhanced light-matter interactions. In this work, we demonstrate the realization of a polaritonic metasurface utilizing the sizable light-matter coupling of excitons in monolayer WSe2 and the collective lattice resonances of nanoplasmonic gold arrays. We developed a novel fabrication method to integrate gold nanodisk arrays in hexagonal boron nitride and thus simultaneously ensure spectrally narrow exciton transitions and their immediate proximity to the near-field of array surface lattice resonances. In the regime of strong light-matter coupling, the resulting van der Waals metasurface exhibits all key characteristics of lattice polaritons, with a directional and linearly polarized far-field emission profile dictated by the underlying nanoplasmonic lattice. Our work can be straightforwardly adapted to other lattice geometries, establishing structured van der Waals metasurfaces as means to engineer polaritonic lattices.

4.
Nano Lett ; 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38597670

RESUMEN

We report experimental and theoretical studies of MoTe2-MoSe2 heterobilayers with rigid moiré superlattices controlled by the twist angle. Using an effective continuum model that combines resonant interlayer electron tunneling with stacking-dependent moiré potentials, we identify the nature of moiré excitons and the dependence of their energies, oscillator strengths, and Landé g-factors on the twist angle. Within the same framework, we interpret distinct signatures of bound complexes among electrons and moiré excitons in nearly collinear heterostacks. Our work provides a fundamental understanding of hybrid moiré excitons and trions in MoTe2-MoSe2 heterobilayers and establishes the material system as a prime candidate for optical studies of correlated phenomena in moiré lattices.

5.
Funct Integr Genomics ; 24(2): 58, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38489049

RESUMEN

Recent studies have shown that NOP2, a nucleolar protein, is up-regulated in various cancers, suggesting a potential link to tumor aggressiveness and unfavorable outcomes. This study examines NOP2's role in lung adenocarcinoma (LUAD), a context where its implications remain unclear. Utilizing bioinformatics, we assessed 513 LUAD and 59 normal tissue samples from The Cancer Genome Atlas (TCGA) to explore NOP2's diagnostic and prognostic significance in LUAD. Additionally, in vitro experiments compared NOP2 expression between Beas-2b and A549 cells. Advanced databases and analytical tools, including LINKEDOMICS, STRING, and TISIDB, were employed to further elucidate NOP2's association with LUAD. Our findings indicate a significantly higher expression of NOP2 mRNA and protein in A549 cells compared to Beas-2b cells (P < 0.001). In LUAD, elevated NOP2 levels were linked to decreased Overall Survival (OS) and advanced clinical stages. Univariate Cox analysis revealed that high NOP2 expression correlated with poorer OS in LUAD (P < 0.01), a finding independently supported by multivariate Cox analysis (P < 0.05). The relationship between NOP2 expression and LUAD risk was presented via a Nomogram. Additionally, Gene Set Enrichment Analysis (GSEA) identified seven NOP2-related signaling pathways. A focal point of our research was the interplay between NOP2 and tumor-immune interactions. Notably, a negative correlation was observed between NOP2 expression and the immune infiltration levels of macrophages, neutrophils, mast cells, Natural Killer (NK) cells, and CD8 + T cells in LUAD. Moreover, the expression of NOP2 was related to the sensitivity of various chemotherapeutic drugs. In vitro, we found that downregulating NOP2 can decrease the proliferation, migration and invasion of A549 cells. Furthermore, NOP2 can regulate Caspase3-mediated apoptosis. Collectively, particularly regarding prognosis, immune infiltration and vitro experiments, these findings suggest NOP2's potential of serving as a poor-prognostic biomarker for LUAD and aggravating the malignancy of lung adenocarcinoma cells.


Asunto(s)
Adenocarcinoma del Pulmón , Neoplasias Pulmonares , Humanos , Proteínas Nucleares , Adenocarcinoma del Pulmón/genética , Apoptosis , Biología Computacional , Neoplasias Pulmonares/genética , ARNt Metiltransferasas
6.
Anal Chem ; 96(1): 292-300, 2024 01 09.
Artículo en Inglés | MEDLINE | ID: mdl-38141016

RESUMEN

Accurate identification of antibiotic resistance genes (ARGs) is crucial for improving treatment and controlling the spread of antibiotic-resistant bacteria (ARB). Herein, a novel PCR-free, centrifugation-free, and label-free magnetic fluorescent biosensor (MFB) was developed by combining polyA-medium DNA-polyT (mDNA, which contained a partial sequence of a target DNA), gold nanoparticle (AuNP)-anchored magnetic nanoparticle (Au@Fe3O4), complementary strand DNA (CS) of the target DNA, DNA concatamer with G-triplex (G3), and thioflavin T (ThT). Thereinto, Au@Fe3O4 nanoparticles were first capped by mDNA strands within 20 min using a simple hot drying method, and then CS was added and hybridized with mDNA on Au@Fe3O4. Second, a DNA concatamer was used to bind with CS on Au@Fe3O4. When an ARG was present in the sample, the CS would recognize it and release the DNA concatamer into solution by a toehold-mediated strand displacement reaction. Finally, under magnetic separation, the free DNA concatamers with G3 were taken out easily and bound with ThT, resulting in strong fluorescence signals. The fluorescence intensity of ThT was positively correlated with the concentration of the ARG. The whole analysis was accomplished within 1.5 h using 96-well plates. Remarkably, our MFB was universal; eight ARGs were detected by replacing the corresponding mDNA and CS in this study. To verify the practicability of our method, 12 clinically isolated strains were analyzed. The results of the MFB method were in good agreement with those of the quantitative real-time PCR method with an area under the curve of 0.92 (95% confidence interval: 0.8479 to 0.9932), sensitivity of 92.00%, and specificity of 91.55%. Above all, the MFB assay established here is simple, low-cost, and universal and has great potential for applications in the identification of ARGs.


Asunto(s)
Técnicas Biosensibles , Nanopartículas del Metal , Antibacterianos/farmacología , Oro , Calefacción , Antagonistas de Receptores de Angiotensina , Inhibidores de la Enzima Convertidora de Angiotensina , ADN/genética , ADN/análisis , Técnicas Biosensibles/métodos
7.
J Med Virol ; 96(3): e29528, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38501378

RESUMEN

The emerging Omicron subvariants have a remarkable ability to spread and escape nearly all current monoclonal antibody (mAb) treatments. Although the virulence of SARS-CoV-2 has now diminished, it remains a significant threat to public health due to its high transmissibility and susceptibility to mutation. Therefore, it is urgent to develop broad-acting and potent therapeutics targeting current and emerging Omicron variants. Here, we identified a panel of Omicron BA.1 spike receptor-binding domain (RBD)-targeted nanobodies (Nbs) from a naive alpaca VHH library. This panel of Nbs exhibited high binding affinity to the spike RBD of wild-type, Alpha B.1.1.7, Beta B.1.351, Delta plus, Omicron BA.1, and BA.2. Through multivalent Nb construction, we obtained a subpanel of ultrapotent neutralizing Nbs against Omicron BA.1, BA.2, BF.7 and even emerging XBB.1.5, and XBB.1.16 pseudoviruses. Protein structure prediction and docking analysis showed that Nb trimer 2F2E5 targets two independent RBD epitopes, thus minimizing viral escape. Taken together, we obtained a panel of broad and ultrapotent neutralizing Nbs against Omicron BA.1, Omicron BA.2, BF.7, XBB.1.5, and XBB.1.16. These multivalent Nbs hold great promise for the treatment against SARS-CoV-2 infection and could possess a superwide neutralizing breadth against novel omicron mutants or recombinants.


Asunto(s)
COVID-19 , SARS-CoV-2 , Anticuerpos de Dominio Único , Humanos , Anticuerpos de Dominio Único/genética , Anticuerpos Monoclonales , Epítopos , Anticuerpos Neutralizantes , Anticuerpos Antivirales
8.
Phys Rev Lett ; 132(7): 076902, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38427888

RESUMEN

We study experimentally and theoretically the hybridization among intralayer and interlayer moiré excitons in a MoSe_{2}/WS_{2} heterostructure with antiparallel alignment. Using a dual-gate device and cryogenic white light reflectance and narrow-band laser modulation spectroscopy, we subject the moiré excitons in the MoSe_{2}/WS_{2} heterostack to a perpendicular electric field, monitor the field-induced dispersion and hybridization of intralayer and interlayer moiré exciton states, and induce a crossover from type I to type II band alignment. Moreover, we employ perpendicular magnetic fields to map out the dependence of the corresponding exciton Landé g factors on the electric field. Finally, we develop an effective theoretical model combining resonant and nonresonant contributions to moiré potentials to explain the observed phenomenology, and highlight the relevance of interlayer coupling for structures with close energetic band alignment as in MoSe_{2}/WS_{2}.

9.
Exp Eye Res ; 243: 109907, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38649019

RESUMEN

Sleep loss is common in modern society and is increasingly associated with eye diseases. However, the precise effects of sleep loss on retinal structure and function, particularly on the retinal circadian system, remain largely unexplored. This study investigates these effects using a chronic sleep deprivation (CSD) model in mice. Our investigation reveals that CSD significantly alters the retinal circadian transcriptome, leading to remarkable changes in the temporal patterns of enriched pathways. This perturbation extends to metabolic and immune-related transcriptomes, coupled with an accumulation of reactive oxygen species in the retina. Notably, CSD rhythmically affects the thickness of the ganglion cell complex, along with diurnal shifts in microglial migration and morphology within the retina. Most critically, we observe a marked decrease in both scotopic and photopic retinal function under CSD conditions. These findings underscore the broad impact of sleep deprivation on retinal health, highlighting its role in altering circadian gene expression, metabolism, immune response, and structural integrity. Our study provides new insights into the broader impact of sleep loss on retinal health.


Asunto(s)
Ritmo Circadiano , Ratones Endogámicos C57BL , Retina , Privación de Sueño , Transcriptoma , Animales , Privación de Sueño/fisiopatología , Privación de Sueño/metabolismo , Privación de Sueño/genética , Ratones , Ritmo Circadiano/fisiología , Masculino , Retina/metabolismo , Retina/fisiopatología , Modelos Animales de Enfermedad , Células Ganglionares de la Retina/patología , Células Ganglionares de la Retina/metabolismo , Electrorretinografía , Regulación de la Expresión Génica , Enfermedad Crónica
10.
Exp Eye Res ; 246: 110008, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39025460

RESUMEN

This study aims to explore the effects of long-term high fructose intake (LHFI) on the structure, functionality, and physiological homeostasis of mouse extra-orbital lacrimal glands (ELGs), a critical component of ocular health. Our findings reveal significant reprogramming of the circadian transcriptome in ELGs following LHFI, alongside the activation of specific inflammatory pathways, as well as metabolic and neural pathways. Notably, LHFI resulted in increased inflammatory infiltration, enhanced lipid deposition, and reduced nerve fiber density in ELGs compared to controls. Functional assessments indicated a marked reduction in lacrimal secretion following cholinergic stimulation in LHFI-treated mice, suggesting impaired gland function. Overall, our results suggest that LHFI disrupts lacrimal gland homeostasis, potentially leading to dry eye disease by altering its structure and secretory function. These insights underscore the profound impact of dietary choices on ocular health and highlight the need for strategies to mitigate these risks.


Asunto(s)
Ritmo Circadiano , Fructosa , Homeostasis , Aparato Lagrimal , Ratones Endogámicos C57BL , Transcriptoma , Animales , Aparato Lagrimal/metabolismo , Aparato Lagrimal/efectos de los fármacos , Ratones , Ritmo Circadiano/fisiología , Masculino , Lágrimas/metabolismo , Síndromes de Ojo Seco/metabolismo , Síndromes de Ojo Seco/genética , Modelos Animales de Enfermedad , Femenino
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