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1.
Mol Cell ; 83(23): 4352-4369.e8, 2023 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-38016474

RESUMEN

Ferroptosis is a non-apoptotic form of regulated cell death. Glutathione (GSH) peroxidase 4 (GPX4) and GSH-independent ferroptosis suppressor protein 1 (FSP1) have been identified as major defenses. Here, we uncover a protective mechanism mediated by GSH S-transferase P1 (GSTP1) by monitoring proteinomic dynamics during ferroptosis. Dramatic downregulation of GSTP1 is caused by SMURF2-mediated GSTP1 ubiquitination and degradation at early stages of ferroptosis. Intriguingly, GSTP1 acts in GPX4- and FSP1-independent manners by catalyzing GSH conjugation of 4-hydroxynonenal and detoxifying lipid hydroperoxides via selenium-independent GSH peroxidase activity. Genetic modulation of the SMURF2/GSTP1 axis or the pharmacological inhibition of GSTP1's catalytic activity sensitized tumor responses to Food and Drug Administration (FDA)-approved ferroptosis-inducing drugs both in vitro and in vivo. GSTP1 expression also confers resistance to immune checkpoint inhibitors by blunting ferroptosis. Collectively, these findings demonstrate a GPX4/FSP1-independent cellular defense mechanism against ferroptosis and suggest that targeting SMURF2/GSTP1 to sensitize cancer cells to ferroptosis has potential as an anticancer therapy.


Asunto(s)
Ferroptosis , Neoplasias , Estados Unidos , Ferroptosis/genética , Ubiquitinación , Regulación hacia Abajo , Glutatión , Peroxidasas , Neoplasias/genética
2.
Cell ; 161(4): 893-906, 2015 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-25936838

RESUMEN

DNA N(6)-methyladenine (6mA) modification is commonly found in microbial genomes and plays important functions in regulating numerous biological processes in bacteria. However, whether 6mA occurs and what its potential roles are in higher-eukaryote cells remain unknown. Here, we show that 6mA is present in Drosophila genome and that the 6mA modification is dynamic and is regulated by the Drosophila Tet homolog, DNA 6mA demethylase (DMAD), during embryogenesis. Importantly, our biochemical assays demonstrate that DMAD directly catalyzes 6mA demethylation in vitro. Further genetic and sequencing analyses reveal that DMAD is essential for development and that DMAD removes 6mA primarily from transposon regions, which correlates with transposon suppression in Drosophila ovary. Collectively, we uncover a DNA modification in Drosophila and describe a potential role of the DMAD-6mA regulatory axis in controlling development in higher eukaryotes.


Asunto(s)
Adenina/análogos & derivados , Metilación de ADN , Drosophila/metabolismo , Adenina/metabolismo , Secuencia de Aminoácidos , Animales , Elementos Transponibles de ADN , Drosophila/embriología , Drosophila/enzimología , Femenino , Regulación del Desarrollo de la Expresión Génica , Datos de Secuencia Molecular , Ovario/metabolismo , Alineación de Secuencia , Metiltransferasa de ADN de Sitio Específico (Adenina Especifica)/metabolismo
3.
Cell ; 161(6): 1437-52, 2015 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-26046443

RESUMEN

Germ cells are vital for transmitting genetic information from one generation to the next and for maintaining the continuation of species. Here, we analyze the transcriptome of human primordial germ cells (PGCs) from the migrating stage to the gonadal stage at single-cell and single-base resolutions. Human PGCs show unique transcription patterns involving the simultaneous expression of both pluripotency genes and germline-specific genes, with a subset of them displaying developmental-stage-specific features. Furthermore, we analyze the DNA methylome of human PGCs and find global demethylation of their genomes. Approximately 10 to 11 weeks after gestation, the PGCs are nearly devoid of any DNA methylation, with only 7.8% and 6.0% of the median methylation levels in male and female PGCs, respectively. Our work paves the way toward deciphering the complex epigenetic reprogramming of the germline with the aim of restoring totipotency in fertilized oocytes.


Asunto(s)
Metilación de ADN , Células Germinativas/metabolismo , Transcriptoma , Movimiento Celular , Cromosomas Humanos X , Análisis por Conglomerados , Embrión de Mamíferos/metabolismo , Femenino , Histonas/metabolismo , Humanos , Masculino , Análisis de Componente Principal , Factores de Transcripción SOX/metabolismo
4.
Nature ; 633(8028): 224-231, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39143215

RESUMEN

Coronaviruses remodel the intracellular host membranes during replication, forming double-membrane vesicles (DMVs) to accommodate viral RNA synthesis and modifications1,2. SARS-CoV-2 non-structural protein 3 (nsp3) and nsp4 are the minimal viral components required to induce DMV formation and to form a double-membrane-spanning pore, essential for the transport of newly synthesized viral RNAs3-5. The mechanism of DMV pore complex formation remains unknown. Here we describe the molecular architecture of the SARS-CoV-2 nsp3-nsp4 pore complex, as resolved by cryogenic electron tomography and subtomogram averaging in isolated DMVs. The structures uncover an unexpected stoichiometry and topology of the nsp3-nsp4 pore complex comprising 12 copies each of nsp3 and nsp4, organized in 4 concentric stacking hexamer rings, mimicking a miniature nuclear pore complex. The transmembrane domains are interdigitated to create a high local curvature at the double-membrane junction, coupling double-membrane reorganization with pore formation. The ectodomains form extensive contacts in a pseudo-12-fold symmetry, belting the pore complex from the intermembrane space. A central positively charged ring of arginine residues coordinates the putative RNA translocation, essential for virus replication. Our work establishes a framework for understanding DMV pore formation and RNA translocation, providing a structural basis for the development of new antiviral strategies to combat coronavirus infection.


Asunto(s)
Membranas Intracelulares , SARS-CoV-2 , Humanos , Arginina/química , Arginina/metabolismo , Microscopía por Crioelectrón , Tomografía con Microscopio Electrónico , Membranas Intracelulares/química , Membranas Intracelulares/metabolismo , Membranas Intracelulares/ultraestructura , Membranas Intracelulares/virología , Modelos Moleculares , Porosidad , Dominios Proteicos , Transporte de ARN , ARN Viral/biosíntesis , ARN Viral/química , ARN Viral/metabolismo , SARS-CoV-2/química , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , SARS-CoV-2/ultraestructura , Proteínas no Estructurales Virales/metabolismo , Proteínas no Estructurales Virales/química , Proteínas no Estructurales Virales/ultraestructura , Replicación Viral , Células HEK293
5.
Proc Natl Acad Sci U S A ; 121(37): e2403038121, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39226359

RESUMEN

Proteostasis and genomic integrity are respectively regulated by the endoplasmic reticulum-associated protein degradation (ERAD) and DNA damage repair signaling pathways, with both pathways essential for carcinogenesis and drug resistance. How these signaling pathways coordinate with each other remains unexplored. We found that ER stress specifically induces the DNA-PKcs-regulated nonhomologous end joining (NHEJ) pathway to amend DNA damage and impede cell death. Intriguingly, sustained ER stress rapidly decreased the activity of DNA-PKcs and DNA damage accumulated, facilitating a switch from adaptation to cell death. This DNA-PKcs inactivation was caused by increased KU70/KU80 protein degradation. Unexpectedly, the ERAD ligase HRD1 was found to efficiently destabilize the classic nuclear protein HDAC1 in the cytoplasm, by catalyzing HDAC1's polyubiquitination at lysine 74, at a late stage of ER stress. By abolishing HDAC1-mediated KU70/KU80 deacetylation, HRD1 transmits ER signals to the nucleus. The resulting enhanced KU70/KU80 acetylation provides binding sites for the nuclear E3 ligase TRIM25, resulting in the promotion of polyubiquitination and the degradation of KU70/KU80 proteins. Both in vitro and in vivo cancer models showed that genetic or pharmacological inhibition of HADC1 or DNA-PKcs sensitizes colon cancer cells to ER stress inducers, including the Food and Drug Administration-approved drug celecoxib. The antitumor effects of the combined approach were also observed in patient-derived xenograft models. These findings identify a mechanistic link between ER stress (ERAD) in the cytoplasm and DNA damage (NHEJ) pathways in the nucleus, indicating that combined anticancer strategies may be developed that induce severe ER stress while simultaneously inhibiting KU70/KU80/DNA-PKcs-mediated NHEJ signaling.


Asunto(s)
Daño del ADN , Proteína Quinasa Activada por ADN , Estrés del Retículo Endoplásmico , Ubiquitina-Proteína Ligasas , Animales , Humanos , Ratones , Línea Celular Tumoral , Reparación del ADN por Unión de Extremidades , Reparación del ADN , Proteína Quinasa Activada por ADN/metabolismo , Proteína Quinasa Activada por ADN/genética , Retículo Endoplásmico/metabolismo , Histona Desacetilasa 1/metabolismo , Histona Desacetilasa 1/genética , Autoantígeno Ku/metabolismo , Autoantígeno Ku/genética , Proteolisis , Transducción de Señal , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina-Proteína Ligasas/genética , Ubiquitinación
6.
Proc Natl Acad Sci U S A ; 121(31): e2321929121, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39047035

RESUMEN

Colorectal cancer and Crohn's disease patients develop pyogenic liver abscesses due to failures of immune cells to fight off bacterial infections. Here, we show that mice lacking iron regulatory protein 2 (Irp2), globally (Irp2-/-) or myeloid cell lineage (Lysozyme 2 promoter-driven, LysM)-specifically (Irp2ΔLysM), are highly susceptible to liver abscesses when the intestinal tissue was injured with dextran sodium sulfate treatment. Further studies demonstrated that Irp2 is required for lysosomal acidification and biogenesis, both of which are crucial for bacterial clearance. In Irp2-deficient liver tissue or macrophages, the nuclear location of transcription factor EB (Tfeb) was remarkably reduced, leading to the downregulation of Tfeb target genes that encode critical components for lysosomal biogenesis. Tfeb mislocalization was reversed by hypoxia-inducible factor 2 inhibitor PT2385 and, independently, through inhibition of lactic acid production. These experimental findings were confirmed clinically in patients with Crohn's disease and through bioinformatic searches in databases from Crohn's disease or ulcerative colitis biopsies showing loss of IRP2 and transcription factor EB (TFEB)-dependent lysosomal gene expression. Overall, our study highlights a mechanism whereby Irp2 supports nuclear translocation of Tfeb and lysosomal function, preserving macrophage antimicrobial activity and protecting the liver against invading bacteria during intestinal inflammation.


Asunto(s)
Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice , Enfermedad de Crohn , Proteína 2 Reguladora de Hierro , Lisosomas , Macrófagos , Animales , Lisosomas/metabolismo , Macrófagos/inmunología , Macrófagos/metabolismo , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/metabolismo , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/genética , Ratones , Humanos , Enfermedad de Crohn/inmunología , Enfermedad de Crohn/metabolismo , Proteína 2 Reguladora de Hierro/metabolismo , Proteína 2 Reguladora de Hierro/genética , Ratones Noqueados , Ratones Endogámicos C57BL , Hígado/metabolismo , Hígado/inmunología , Hígado/patología
7.
Plant Cell ; 35(12): 4217-4237, 2023 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-37647529

RESUMEN

Membrane protein homeostasis is fine-tuned by the cellular pathways for vacuolar degradation and recycling, which ultimately facilitate plant growth and cell-environment interactions. The endosomal sorting complex required for transport (ESCRT) machinery plays important roles in regulating intraluminal vesicle (ILV) formation and membrane protein sorting to vacuoles. We previously showed that the plant-specific ESCRT component FYVE DOMAIN PROTEIN REQUIRED FOR ENDOSOMAL SORTING1 (FREE1) performs multiple functions in plants, although the underlying mechanisms remain elusive. In this study, we performed a suppressor screen of the FREE1-RNAi mutant and identified and characterized 2 suppressor of free1 (sof) mutants in Arabidopsis (Arabidopsis thaliana). These mutants, sof10 and sof641, result in a premature stop codon or a missense mutation in AT5G10370, respectively. This gene was named DEAH and RING domain-containing protein as FREE1 suppressor 1 (DRIF1). DRIF1 has a homologous gene, DRIF2, in the Arabidopsis genome with 95% identity to DRIF1. The embryos of drif1 drif2 mutants arrested at the globular stage and formed enlarged multivesicular bodies (MVBs) with an increased number of ILVs. DRIF1 is a membrane-associated protein that coordinates with retromer component sorting nexin 1 to regulate PIN-FORMED2 recycling to the plasma membrane. Altogether, our data demonstrate that DRIF1 is a unique retromer interactor that orchestrates FREE1-mediated ILV formation of MVBs and vacuolar sorting of membrane proteins for degradation in plants.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Nexinas de Clasificación/genética , Nexinas de Clasificación/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas de Plantas/metabolismo , Complejos de Clasificación Endosomal Requeridos para el Transporte/metabolismo , Proteostasis , Transporte de Proteínas/genética , Plantas/metabolismo , Proteínas de Transporte Vesicular/genética , Proteínas de Transporte Vesicular/metabolismo
8.
J Neurosci ; 44(13)2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38378273

RESUMEN

Patients with chronic pain often develop comorbid depressive symptoms, which makes the pain symptoms more complicated and refractory. However, the underlying mechanisms are poorly known. Here, in a repeated complete Freund's adjuvant (CFA) male mouse model, we reported a specific regulatory role of the paraventricular thalamic nucleus (PVT) glutamatergic neurons, particularly the anterior PVT (PVA) neurons, in mediating chronic pain and depression comorbidity (CDC). Our c-Fos protein staining observed increased PVA neuronal activity in CFA-CDC mice. In wild-type mice, chemogenetic activation of PVA glutamatergic neurons was sufficient to decrease the 50% paw withdrawal thresholds (50% PWTs), while depressive-like behaviors evaluated with immobile time in tail suspension test (TST) and forced swim test (FST) could only be achieved by repeated chemogenetic activation. Chemogenetic inhibition of PVA glutamatergic neurons reversed the decreased 50% PWTs in CFA mice without depressive-like symptoms and the increased TST and FST immobility in CFA-CDC mice. Surprisingly, in CFA-CDC mice, chemogenetically inhibiting PVA glutamatergic neurons failed to reverse the decrease of 50% PWTs, which could be restored by rapid-onset antidepressant S-ketamine. Further behavioral tests in chronic restraint stress mice and CFA pain mice indicated that PVA glutamatergic neuron inhibition and S-ketamine independently alleviate sensory and affective pain. Molecular profiling and pharmacological studies revealed the 5-hydroxytryptamine receptor 1D (Htr1d) in CFA pain-related PVT engram neurons as a potential target for treating CDC. These findings identified novel CDC neuronal and molecular mechanisms in the PVT and provided insight into the complicated pain neuropathology under a comorbid state with depression and related drug development.


Asunto(s)
Dolor Crónico , Ketamina , Humanos , Ratones , Masculino , Animales , Dolor Crónico/metabolismo , Depresión/tratamiento farmacológico , Tálamo , Neuronas/metabolismo , Comorbilidad
9.
J Biol Chem ; 300(9): 107639, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39122013

RESUMEN

Inflammatory bowel diseases (IBDs) are complex disorders. Iron accumulates in the inflamed tissue of IBD patients, yet neither a mechanism for the accumulation nor its implication on the course of inflammation is known. We hypothesized that the inflammation modifies iron homeostasis, affects tissue iron distribution, and that this in turn perpetuates the inflammation. This study analyzed human biopsies, animal models, and cellular systems to decipher the role of iron homeostasis in IBD. We found inflammation-mediated modifications of iron distribution, and iron-decoupled activation of the iron regulatory protein (IRP) 1. To understand the role of IRP1 in the course of this inflammation-associated iron pattern, a novel cellular coculture model was established, which replicated the iron-pattern observed in vivo, and supported involvement of nitric oxide in the activation of IRP1 and the typical iron pattern in inflammation. Importantly, deletion of IRP1 from an IBD mouse model completely abolished both, the misdistribution of iron and intestinal inflammation. These findings suggest that IRP1 plays a central role in the coordination of the inflammatory response in the intestinal mucosa and that it is a viable candidate for therapeutic intervention in IBD.


Asunto(s)
Inflamación , Enfermedades Inflamatorias del Intestino , Proteína 1 Reguladora de Hierro , Hierro , Animales , Humanos , Proteína 1 Reguladora de Hierro/metabolismo , Proteína 1 Reguladora de Hierro/genética , Hierro/metabolismo , Enfermedades Inflamatorias del Intestino/metabolismo , Enfermedades Inflamatorias del Intestino/patología , Enfermedades Inflamatorias del Intestino/genética , Ratones , Inflamación/metabolismo , Inflamación/patología , Inflamación/genética , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patología , Ratones Noqueados , Masculino , Modelos Animales de Enfermedad , Óxido Nítrico/metabolismo , Femenino , Ratones Endogámicos C57BL
10.
EMBO J ; 40(14): e105985, 2021 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-34121209

RESUMEN

Autophagy is a process through which intracellular cargoes are catabolised inside lysosomes. It involves the formation of autophagosomes initiated by the serine/threonine kinase ULK and class III PI3 kinase VPS34 complexes. Here, unbiased phosphoproteomics screens in mouse embryonic fibroblasts deleted for Ulk1/2 reveal that ULK loss significantly alters the phosphoproteome, with novel high confidence substrates identified including VPS34 complex member VPS15 and AMPK complex subunit PRKAG2. We identify six ULK-dependent phosphorylation sites on VPS15, mutation of which reduces autophagosome formation in cells and VPS34 activity in vitro. Mutation of serine 861, the major VPS15 phosphosite, decreases both autophagy initiation and autophagic flux. Analysis of VPS15 knockout cells reveals two novel ULK-dependent phenotypes downstream of VPS15 removal that can be partially recapitulated by chronic VPS34 inhibition, starvation-independent accumulation of ULK substrates and kinase activity-regulated recruitment of autophagy proteins to ubiquitin-positive structures.


Asunto(s)
Homólogo de la Proteína 1 Relacionada con la Autofagia/metabolismo , Autofagia/fisiología , Fosfatidilinositol 3-Quinasas Clase III/metabolismo , Proteína de Clasificación Vacuolar VPS15/metabolismo , Proteínas Quinasas Activadas por AMP/metabolismo , Animales , Autofagosomas/metabolismo , Proteínas Relacionadas con la Autofagia/metabolismo , Fibroblastos/metabolismo , Células HEK293 , Humanos , Ratones , Proteómica/métodos
11.
Plant Cell ; 34(11): 4255-4273, 2022 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-35775937

RESUMEN

Lipid droplets (LDs) stored during seed development are mobilized and provide essential energy and lipids to support seedling growth upon germination. Triacylglycerols (TAGs) are the main neutral lipids stored in LDs. The lipase SUGAR DEPENDENT 1 (SDP1), which hydrolyzes TAGs in Arabidopsis thaliana, is localized on peroxisomes and traffics to the LD surface through peroxisomal extension, but the underlying mechanism remains elusive. Here, we report a previously unknown function of a plant-unique endosomal sorting complex required for transport (ESCRT) component FYVE DOMAIN PROTEIN REQUIRED FOR ENDOSOMAL SORTING 1 (FREE1) in regulating peroxisome/SDP1-mediated LD turnover in Arabidopsis. We showed that LD degradation was impaired in germinating free1 mutant; moreover, the tubulation of SDP1- or PEROXIN 11e (PEX11e)-marked peroxisomes and the migration of SDP1-positive peroxisomes to the LD surface were altered in the free1 mutant. Electron tomography analysis showed that peroxisomes failed to form tubules to engulf LDs in free1, unlike in the wild-type. FREE1 interacted directly with both PEX11e and SDP1, suggesting that these interactions may regulate peroxisomal extension and trafficking of the lipase SDP1 to LDs. Taken together, our results demonstrate a pivotal role for FREE1 in LD degradation in germinating seedlings via regulating peroxisomal tubulation and SDP1 targeting.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Plantones/metabolismo , Peroxisomas/metabolismo , Proteínas de Arabidopsis/metabolismo , Gotas Lipídicas/metabolismo , Lipasa/metabolismo , Complejos de Clasificación Endosomal Requeridos para el Transporte/genética , Complejos de Clasificación Endosomal Requeridos para el Transporte/metabolismo , Lípidos , Hidrolasas de Éster Carboxílico/metabolismo , Proteínas de Transporte Vesicular/genética , Proteínas de Transporte Vesicular/metabolismo
12.
Proc Natl Acad Sci U S A ; 119(6)2022 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-35121659

RESUMEN

Ca2+ release from the endoplasmic reticulum (ER) is an essential event in the modulation of Ca2+ homeostasis, which is coordinated by multiple biological processes, ranging from cell proliferation to apoptosis. Deregulated Ca2+ homeostasis is linked with various cancer hallmarks; thus, uncovering the mechanisms underlying Ca2+ homeostasis dynamics may lead to new anticancer treatment strategies. Here, we demonstrate that a reported Ca2+-channel protein TMCO1 (transmembrane and coiled-coil domains 1) is overexpressed in colon cancer tissues at protein levels but not at messenger RNA levels in colon cancer. Further study revealed that TMCO1 is a substrate of ER-associated degradation E3 ligase Gp78. Intriguingly, Gp78-mediated TMCO1 degradation at K186 is under the control of the iASPP (inhibitor of apoptosis-stimulating protein of p53) oncogene. Mechanistically, iASPP robustly reduces ER Ca2+ stores, mainly by competitively binding with Gp78 and interfering with Gp78-mediated TMCO1 degradation. A positive correlation between iASPP and TMCO1 proteins is further validated in human colon tissues. Inhibition of iASPP-TMCO1 axis promotes cytosolic Ca2+ overload-induced apoptotic cell death, reducing tumor growth both in vitro and in vivo. Thus, iASPP-TMCO1 represents a promising anticancer treatment target by modulating Ca2+ homeostasis.


Asunto(s)
Canales de Calcio/metabolismo , Calcio/metabolismo , Proliferación Celular/fisiología , Resistencia a Medicamentos/fisiología , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Neoplasias/metabolismo , Receptores del Factor Autocrino de Motilidad/metabolismo , Proteínas Represoras/metabolismo , Animales , Apoptosis/fisiología , Línea Celular Tumoral , Retículo Endoplásmico/metabolismo , Degradación Asociada con el Retículo Endoplásmico/fisiología , Células HCT116 , Células HT29 , Homeostasis , Humanos , Ratones , Ratones Desnudos
13.
J Am Chem Soc ; 2024 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-39367840

RESUMEN

Fluorination is a useful approach for tailoring the physicochemical properties of nanocarbon materials. However, owing to the violent reactivity of fluorination, achieving edge-perfluorination of nanographene while maintaining its original π-conjugated structure is challenging. Instead of using traditional fluorination, here, we employed a bottom-up strategy involving fluorine preinstallation and synthesized decafluorinated and perfluorinated warped nanographenes (DFWNG and PFWNG, respectively) through a 10-fold Suzuki-Miyaura coupling followed by a harsh Scholl reaction, whereby precisely edge-perfluorinated nanographene with an intact π-conjugated structure was achieved for the first time. X-ray crystallography confirmed the intact π-conjugated structure and more twisted saddle-shaped geometry of PFWNG compared to that of DFWNG. Dynamic study revealed that the 26-ring carbon framework of PFWNG is less flexible than that of DFWNG and the pristine WNG, enabling chirality resolution of PFWNG and facilitating the achievement of CD spectra at -10 °C. The edge-perfluorination of PFWNG resulted in improved solubility, lower lowest unoccupied molecular orbital, and a surface electrostatic potentials/dipole moment direction opposite those of the pristine WNG. Likely owing to its intact π-conjugated structure, PFWNG exhibits comparable electron mobility with well-known PC61BM. Furthermore, perfluorination improves thermal stability and hydrophobicity, making PFWNG suitable for use as a thermostable/hydrophobic n-type semiconductor material. In the future, this fluorination strategy can be used to synthesize other perfluorinated nanocarbon materials, such as perfluorinated graphene nanoribbons and porous nanocarbon.

14.
Curr Issues Mol Biol ; 46(6): 5242-5256, 2024 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-38920986

RESUMEN

The Asteraceae are widely distributed throughout the world, with diverse functions and large genomes. Many of these genes remain undiscovered and unstudied. In this study, we discovered a new gene ClNUM1 in Chrysanthemum lavandulifolium and studied its function. In this study, bioinformatics, RT-qPCR, paraffin sectioning, and tobacco transgenics were utilized to bioinformatically analyze and functionally study the three variable splice variants of the unknown gene ClNUM1 cloned from C. lavandulifolium. The results showed that ClNUM1.1 and ClNUM1.2 had selective 3' splicing and selective 5' splicing, and ClNUM1.3 had selective 5' splicing. When the corresponding transgenic tobacco plants were subjected to abiotic stress treatment, in the tobacco seedlings, the ClNUM1.1 gene and the ClNUM1.2 gene enhanced salt and low-temperature tolerance and the ClNUM1.3 gene enhanced low-temperature tolerance; in mature tobacco plants, the ClNUM1.1 gene was able to enhance salt and low-temperature tolerance, and the ClNUM1.2 and ClNUM1.3 genes were able to enhance low-temperature tolerance. In summary, there are differences in the functions of the different splice variants and the different seedling stages of transgenic tobacco, but all of them enhanced the resistance of tobacco to a certain extent. The analysis and functional characterization of the ClNUM1 gene provided new potential genes and research directions for abiotic resistance breeding in Chrysanthemum.

15.
Cancer Sci ; 115(9): 3127-3142, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38992901

RESUMEN

The incomplete prediction of prognosis in esophageal squamous cell carcinoma (ESCC) patients is attributed to various therapeutic interventions and complex prognostic factors. Consequently, there is a pressing demand for enhanced predictive biomarkers that can facilitate clinical management and treatment decisions. This study recruited 491 ESCC patients who underwent surgical treatment at Huashan Hospital, Fudan University. We incorporated 14 blood metabolic indicators and identified independent prognostic indicators for overall survival through univariate and multivariate analyses. Subsequently, a metabolism score formula was established based on the biochemical markers. We constructed a nomogram and machine learning models utilizing the metabolism score and clinically significant prognostic features, followed by an evaluation of their predictive accuracy and performance. We identified alkaline phosphatase, free fatty acids, homocysteine, lactate dehydrogenase, and triglycerides as independent prognostic indicators for ESCC. Subsequently, based on these five indicators, we established a metabolism score that serves as an independent prognostic factor in ESCC patients. By utilizing this metabolism score in conjunction with clinical features, a nomogram can precisely predict the prognosis of ESCC patients, achieving an area under the curve (AUC) of 0.89. The random forest (RF) model showed superior predictive ability (AUC = 0.90, accuracy = 86%, Matthews correlation coefficient = 0.55). Finally, we used an RF model with optimal performance to establish an online predictive tool. The metabolism score developed in this study serves as an independent prognostic indicator for ESCC patients.


Asunto(s)
Biomarcadores de Tumor , Progresión de la Enfermedad , Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Aprendizaje Automático , Nomogramas , Humanos , Carcinoma de Células Escamosas de Esófago/patología , Carcinoma de Células Escamosas de Esófago/metabolismo , Carcinoma de Células Escamosas de Esófago/mortalidad , Masculino , Femenino , Neoplasias Esofágicas/patología , Neoplasias Esofágicas/mortalidad , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/sangre , Persona de Mediana Edad , Pronóstico , Biomarcadores de Tumor/sangre , Biomarcadores de Tumor/metabolismo , Anciano , Adulto
16.
Pharmacogenet Genomics ; 34(6): 175-183, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38640061

RESUMEN

OBJECTIVES: Reference materials for in-vitro diagnostic reagents play a critical role in determining the quality of reagents and ensuring the accuracy of clinical test results. This study aimed to establish a national reference material (NRM) for detecting cytochrome P450 (CYP) genes related to drug metabolism by screening databases on the Chinese population to identify CYP gene polymorphism characteristics. METHODS: To prepare the NRM, we used DNA extracted from healthy human immortalized B lymphoblastoid cell lines as the raw material. Samples of these cell lines were obtained from the Chinese Population PGx Gene Polymorphism Biobank. Further, we used Sanger sequencing, next-generation sequencing, and commercial assay kits to validate the polymorphic genotypes. RESULTS: Among the CYP superfamily genes, we confirmed 24 riboswitch loci related to drug metabolism, with evidence levels of 1A, 2A, 3, and 4. We confirmed the polymorphic loci and validated their genotypes using various sequencing techniques. Our results were consistent with the polymorphism information of samples obtained from the biobank, thus demonstrating high precision and stability of the established NRM. CONCLUSION: An NRM (360 056-202 201) for CYP genetic testing covering 24 loci related to drug metabolism was established and approved to assess in-vitro diagnostic reagents containing CYP family gene polymorphisms and perform clinical inter-room quality evaluations.


Asunto(s)
Sistema Enzimático del Citocromo P-450 , Pruebas Genéticas , Humanos , Línea Celular , China , Sistema Enzimático del Citocromo P-450/genética , Pruebas Genéticas/normas , Pruebas Genéticas/métodos , Genotipo , Secuenciación de Nucleótidos de Alto Rendimiento/normas , Polimorfismo Genético , Estándares de Referencia , Pueblos del Este de Asia/genética
17.
Antimicrob Agents Chemother ; 68(9): e0085024, 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39046242

RESUMEN

The metabolic state of bacteria significantly contributes to their resistance to antibiotics; however, the specific metabolic mechanisms conferring antimicrobial resistance in Helicobacter pylori remain largely understudied. Employing transcriptomic and non-targeted metabolomics, we characterized the metabolic reprogramming of H. pylori when challenged with antibiotic agents. We observed a notable increase in both genetic and key proteomic components involved in fatty acid biosynthesis. Inhibition of this pathway significantly enhanced the antibiotic susceptibility of the sensitive and multidrug-resistant H. pylori strains while also disrupting their biofilm-forming capacities. Further analysis revealed that antibiotic treatment induced a stringent response, triggering the expression of the hp0560-hp0557 operon regulated by Sigma28 (σ28). This activation in turn stimulated the fatty acid biosynthetic pathway, thereby enhancing the antibiotic tolerance of H. pylori. Our findings reveal a novel adaptive strategy employed by H. pylori to withstand antibiotic stress.


Asunto(s)
Antibacterianos , Proteínas Bacterianas , Biopelículas , Farmacorresistencia Bacteriana Múltiple , Ácidos Grasos , Helicobacter pylori , Antibacterianos/farmacología , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Biopelículas/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Farmacorresistencia Bacteriana Múltiple/genética , Ácidos Grasos/biosíntesis , Ácidos Grasos/metabolismo , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , Helicobacter pylori/efectos de los fármacos , Helicobacter pylori/genética , Pruebas de Sensibilidad Microbiana , Operón , Factor sigma/genética , Factor sigma/metabolismo
18.
Antimicrob Agents Chemother ; 68(4): e0167923, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38386782

RESUMEN

The increasing antibiotic resistance of Helicobacter pylori primarily driven by genetic mutations poses a significant clinical challenge. Although previous research has suggested that antibiotics could induce genetic mutations in H. pylori, the molecular mechanisms regulating the antibiotic induction remain unclear. In this study, we applied various techniques (e.g., fluorescence microscopy, flow cytometry, and multifunctional microplate reader) to discover that three different types of antibiotics could induce the intracellular generation of reactive oxygen species (ROS) in H. pylori. It is well known that ROS, a critical factor contributing to bacterial drug resistance, not only induces damage to bacterial genomic DNA but also inhibits the expression of genes associated with DNA damage repair, thereby increasing the mutation rate of bacterial genes and leading to drug resistance. However, further research is needed to explore the molecular mechanisms underlying the ROS inhibition of the expression of DNA damage repair-related genes in H. pylori. In this work, we validated that ROS could trigger an allosteric change in the iron uptake regulatory protein Fur, causing its transition from apo-Fur to holo-Fur, repressing the expression of the regulatory protein ArsR, ultimately causing the down-regulation of key DNA damage repair genes (e.g., mutS and mutY); this cascade increased the genomic DNA mutation rate in H. pylori. This study unveils a novel mechanism of antibiotic-induced resistance in H. pylori, providing crucial insights for the prevention and control of antibiotic resistance in H. pylori.


Asunto(s)
Infecciones por Helicobacter , Helicobacter pylori , Humanos , Helicobacter pylori/genética , Helicobacter pylori/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Antibacterianos/farmacología , Antibacterianos/metabolismo , ADN Bacteriano/metabolismo
19.
Anal Chem ; 96(28): 11595-11602, 2024 07 16.
Artículo en Inglés | MEDLINE | ID: mdl-38950152

RESUMEN

Timely diagnosis, monitoring, and management of chronic wounds play crucial roles in improving patients' quality of life, but clinical evaluation of chronic wounds is still ambiguous and relies heavily on the experience of clinician, resulting in increased social and financial burden and delay of optimal treatment. During the different stages of the healing process, specific and dynamic changes of pH values in the wound exudate can be used as biomarkers to reflect the wound status. Herein, a pH-responsive agent with well-behaved photoacoustic (PA) properties, nitrazine yellow (NY), was incorporated in poly(vinyl alcohol)/sucrose (PVA/Suc) hydrogel to construct a wearable pH-sensing patch (PVA/Suc/NY hydrogel) for monitoring of pH values during chronic wound healing. According to Rosencwaig-Gersho theory and the combination of 3D printing technology, the PA chamber volume and chopping frequency were systematically optimized to improve the sensitivity of the PA analytical system. The prepared PVA/Suc/NY hydrogel patch had excellent mechanical properties and flexibility and could maintain conformal contact with skin. Moreover, combined with the miniaturized PA analytical device, it had the potential to detect pH values (5.0-9.0) free from the color interference of blood and therapeutic drugs, which provides a valuable strategy for wound pH value monitoring by PA quantitation. This strategy of combining the wearable hydrogel patch with portable PA analysis offers broad new prospects for the treatment and management of chronic wounds due to its features of simple operation, time savings, and anti-interference.


Asunto(s)
Hidrogeles , Técnicas Fotoacústicas , Dispositivos Electrónicos Vestibles , Concentración de Iones de Hidrógeno , Hidrogeles/química , Animales , Cicatrización de Heridas/efectos de los fármacos , Alcohol Polivinílico/química , Humanos
20.
BMC Med ; 22(1): 181, 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38685041

RESUMEN

BACKGROUND: Early pregnancy is a critical window for neural system programming; however, the association of first-trimester fetal size with children's neurodevelopment remains to be assessed. This study aimed to explore the association between first-trimester fetal size and children's neurodevelopment and to examine whether intrauterine accelerated growth could compensate for the detrimental effects of first-trimester restricted growth on childhood neurodevelopment. METHODS: The participants were from a birth cohort enrolled from March 2014 to March 2019 in Wuhan, China. A total of 2058 fetuses with crown to rump length (CRL) (a proxy of first-trimester fetal size) measurements in the first trimester and neurodevelopmental assessment at age 2 years were included. We measured the first-trimester CRL and defined three fetal growth patterns based on the growth rate of estimated fetal weight from mid to late pregnancy. The neurodevelopment was assessed using the Bayley Scales of Infant Development of China Revision at 2 years. RESULTS: Each unit (a Z score) increase of first-trimester CRL was associated with increased scores in mental developmental index (MDI) (adjusted beta estimate = 1.19, (95% CI: 0.42, 1.95), P = 0.03) and psychomotor developmental index (PDI) (adjusted beta estimate = 1.36, (95% CI: 0.46, 2.26), P < 0.01) at age 2 years, respectively. No significant association was observed between fetal growth rate and PDI. For children with restricted first-trimester fetal size (the lowest tertile of first-trimester CRL), those with "intrauterine accelerated growth" pattern (higher growth rates) had significantly higher MDI (adjusted beta estimate = 6.14, (95% CI: 3.80, 8.49), P < 0.001) but indistinguishable PDI compared to those with "intrauterine faltering growth" pattern (lower growth rates). Main limitations of this study included potential misclassification of gestational age due to recall bias of the last menstrual period and residual confounding. CONCLUSIONS: The current study suggests that restricted first-trimester fetal size is associated with mental and psychomotor developmental delay in childhood. However, in children with restricted first-trimester fetal size, intrauterine accelerated growth was associated with improved mental development but had little effect on psychomotor development. Additional studies are needed to validate the results in diverse populations.


Asunto(s)
Desarrollo Infantil , Desarrollo Fetal , Primer Trimestre del Embarazo , Humanos , Femenino , Embarazo , Desarrollo Fetal/fisiología , Preescolar , Desarrollo Infantil/fisiología , China , Masculino , Estudios de Cohortes , Adulto , Largo Cráneo-Cadera
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