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1.
Nature ; 631(8020): 300-306, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38898282

RESUMEN

Graphene-based, high-quality, two-dimensional electronic systems have emerged as a highly tunable platform for studying superconductivity1-21. Specifically, superconductivity has been observed in both electron- and hole-doped twisted graphene moiré systems1-17, whereas in crystalline graphene systems, superconductivity has so far been observed only in hole-doped rhombohedral trilayer graphene (RTG)18 and hole-doped Bernal bilayer graphene (BBG)19-21. Recently, enhanced superconductivity has been demonstrated20,21 in BBG because of the proximity to a monolayer WSe2. Here we report the observation of superconductivity and a series of flavour-symmetry-breaking phases in electron- and hole-doped BBG/WSe2 devices by electrostatic doping. The strength of the observed superconductivity is tunable by applied vertical electric fields. The maximum Berezinskii-Kosterlitz-Thouless transition temperature for the electron- and hole-doped superconductivity is about 210 mK and 400 mK, respectively. Superconductivities emerge only when the applied electric fields drive the BBG electron or hole wavefunctions towards the WSe2 layer, underscoring the importance of the WSe2 layer in the observed superconductivity. The hole-doped superconductivity violates the Pauli paramagnetic limit, consistent with an Ising-like superconductor. By contrast, the electron-doped superconductivity obeys the Pauli limit, although the proximity-induced Ising spin-orbit coupling is also notable in the conduction band. Our findings highlight the rich physics associated with the conduction band in BBG, paving the way for further studies into the superconducting mechanisms of crystalline graphene and the development of superconductor devices based on BBG.

2.
Proc Natl Acad Sci U S A ; 121(34): e2409343121, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39136994

RESUMEN

Mutations in the PSEN genes are the major cause of familial Alzheimer's disease, and presenilin (PS) is the catalytic subunit of γ-secretase, which cleaves type I transmembrane proteins, including the amyloid precursor protein (APP) to release Aß peptides. While PS plays an essential role in the protection of neuronal survival, PSEN mutations also increase the ratio of Aß42/Aß40. Thus, it remains unresolved whether PSEN mutations cause AD via a loss of its essential function or increases of Aß42/Aß40. Here, we test whether the knockin (KI) allele of Psen1 L435F, the most severe FAD mutation located closest to the active site of γ-secretase, causes age-dependent cortical neurodegeneration independent of Aß by crossing various Psen mutant mice to the App-null background. We report that removing Aß completely through APP deficiency has no impact on the age-dependent neurodegeneration in Psen mutant mice, as shown by the absence of effects on the reduced cortical volume and decreases of cortical neurons at the ages of 12 and 18 mo. The L435F KI allele increases Aß42/Aß40 in the cerebral cortex while decreasing de novo production and steady-state levels of Aß42 and Aß40 in the presence of APP. Furthermore, APP deficiency does not alleviate elevated apoptotic cell death in the cerebral cortex of Psen mutant mice at the ages of 2, 12, and 18 mo, nor does it affect the progressive microgliosis in these mice. Our findings demonstrate that Psen1 mutations cause age-dependent neurodegeneration independent of Aß, providing further support for a loss-of-function pathogenic mechanism underlying PSEN mutations.


Asunto(s)
Enfermedad de Alzheimer , Péptidos beta-Amiloides , Corteza Cerebral , Mutación , Presenilina-1 , Presenilina-1/genética , Presenilina-1/metabolismo , Animales , Péptidos beta-Amiloides/metabolismo , Péptidos beta-Amiloides/genética , Ratones , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/patología , Enfermedad de Alzheimer/metabolismo , Corteza Cerebral/patología , Corteza Cerebral/metabolismo , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Secretasas de la Proteína Precursora del Amiloide/genética , Secretasas de la Proteína Precursora del Amiloide/metabolismo , Neuronas/metabolismo , Neuronas/patología , Ratones Transgénicos , Humanos
3.
PLoS Pathog ; 20(1): e1011823, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38236820

RESUMEN

A variety of coordinated host-cell responses are activated as defense mechanisms against pore-forming toxins (PFTs). Bacillus thuringiensis (Bt) is a worldwide used biopesticide whose efficacy and precise application methods limits its use to replace synthetic pesticides in agricultural settings. Here, we analyzed the intestinal defense mechanisms of two lepidopteran insect pests after intoxication with sublethal dose of Bt PFTs to find out potential functional genes. We show that larval intestinal epithelium was initially damaged by the PFTs and that larval survival was observed after intestinal epithelium regeneration. Further analyses showed that the intestinal regeneration caused by Cry9A protein is regulated through c-Jun NH (2) terminal kinase (JNK) and Janus tyrosine kinase/signal transducer and activator of transcription (JAK/STAT) signaling pathways. JAK/STAT signaling regulates intestinal regeneration through proliferation and differentiation of intestinal stem cells to defend three different Bt proteins including Cry9A, Cry1F or Vip3A in both insect pests, Chilo suppressalis and Spodoptera frugiperda. Consequently, a nano-biopesticide was designed to improve pesticidal efficacy based on the combination of Stat double stranded RNA (dsRNA)-nanoparticles and Bt strain. This formulation controlled insect pests with better effect suggesting its potential use to reduce the use of synthetic pesticides in agricultural settings for pest control.


Asunto(s)
Bacillus thuringiensis , Plaguicidas , Animales , Bacillus thuringiensis/genética , Quinasas Janus/genética , Tirosina , Endotoxinas/genética , Insectos , Spodoptera/genética , Larva , Plaguicidas/farmacología , Regeneración , Proteínas Bacterianas/farmacología , Proteínas Bacterianas/genética , Proteínas Hemolisinas/farmacología , Proteínas Hemolisinas/genética , Plantas Modificadas Genéticamente , Control Biológico de Vectores/métodos
4.
Proc Natl Acad Sci U S A ; 120(42): e2306714120, 2023 10 17.
Artículo en Inglés | MEDLINE | ID: mdl-37816062

RESUMEN

Mutations in the Presenilin (PSEN1 and PSEN2) genes are the major cause of early-onset familial Alzheimer's disease (FAD). Presenilin (PS) is the catalytic subunit of the γ-secretase complex, which cleaves type I transmembrane proteins, such as Notch and the amyloid precursor protein (APP), and plays an evolutionarily conserved role in the protection of neuronal survival during aging. FAD PSEN1 mutations exhibit impaired γ-secretase activity in cell culture, in vitro, and knockin (KI) mouse brains, and the L435F mutation is the most severe in reducing γ-secretase activity and is located closest to the active site of γ-secretase. Here, we report that introduction of the codon-optimized wild-type human PSEN1 cDNA by adeno-associated virus 9 (AAV9) results in broadly distributed, sustained, low to moderate levels of human PS1 (hPS1) expression and rescues impaired γ-secretase activity in the cerebral cortex of Psen mutant mice either lacking PS or expressing the Psen1 L435F KI allele, as evaluated by endogenous γ-secretase substrates of APP and recombinant γ-secretase products of Notch intracellular domain and Aß peptides. Furthermore, introduction of hPS1 by AAV9 alleviates impairments of synaptic plasticity and learning and memory in Psen mutant mice. Importantly, AAV9 delivery of hPS1 ameliorates neurodegeneration in the cerebral cortex of aged Psen mutant mice, as shown by the reversal of age-dependent loss of cortical neurons and elevated microgliosis and astrogliosis. These results together show that moderate hPS1 expression by AAV9 is sufficient to rescue impaired γ-secretase activity, synaptic and memory deficits, and neurodegeneration caused by Psen mutations in mouse models.


Asunto(s)
Enfermedad de Alzheimer , Secretasas de la Proteína Precursora del Amiloide , Humanos , Ratones , Animales , Anciano , Secretasas de la Proteína Precursora del Amiloide/genética , Secretasas de la Proteína Precursora del Amiloide/metabolismo , Presenilina-1/genética , Presenilina-1/metabolismo , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/terapia , Enfermedad de Alzheimer/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Mutación , Trastornos de la Memoria/genética , Trastornos de la Memoria/terapia , Presenilina-2/genética , Péptidos beta-Amiloides/metabolismo
5.
Proc Natl Acad Sci U S A ; 120(47): e2309227120, 2023 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-37963245

RESUMEN

Spatial transcriptomics technology has revolutionized our understanding of cell types and tissue organization, opening possibilities for researchers to explore transcript distributions at subcellular levels. However, existing methods have limitations in resolution, sensitivity, or speed. To overcome these challenges, we introduce SPRINTseq (Spatially Resolved and signal-diluted Next-generation Targeted sequencing), an innovative in situ sequencing strategy that combines hybrid block coding and molecular dilution strategies. Our method enables fast and sensitive high-resolution data acquisition, as demonstrated by recovering over 142 million transcripts using a 108-gene panel from 453,843 cells from four mouse brain coronal slices in less than 2 d. Using this advanced technology, we uncover the cellular and subcellular molecular architecture of Alzheimer's disease, providing additional information into abnormal cellular behaviors and their subcellular mRNA distribution. This improved spatial transcriptomics technology holds great promise for exploring complex biological processes and disease mechanisms.


Asunto(s)
Perfilación de la Expresión Génica , Secuenciación de Nucleótidos de Alto Rendimiento , Animales , Ratones , ARN Mensajero/genética , Transcriptoma
6.
Mol Microbiol ; 122(2): 201-212, 2024 08.
Artículo en Inglés | MEDLINE | ID: mdl-38922722

RESUMEN

An arsenate reductase (Car1) from the Bacteroidetes species Rufibacter tibetensis 1351T was isolated from the Tibetan Plateau. The strain exhibits resistance to arsenite [As(III)] and arsenate [As(V)] and reduces As(V) to As(III). Here we shed light on the mechanism of enzymatic reduction by Car1. AlphaFold2 structure prediction, active site energy minimization, and steady-state kinetics of wild-type and mutant enzymes give insight into the catalytic mechanism. Car1 is structurally related to calcineurin-like metallophosphoesterases (MPPs). It functions as a binuclear metal hydrolase with limited phosphatase activity, particularly relying on the divalent metal Ni2+. As an As(V) reductase, it displays metal promiscuity and is coupled to the thioredoxin redox cycle, requiring the participation of two cysteine residues, Cys74 and Cys76. These findings suggest that Car1 evolved from a common ancestor of extant phosphatases by incorporating a redox function into an existing MPP catalytic site. Its proposed mechanism of arsenate reduction involves Cys74 initiating a nucleophilic attack on arsenate, leading to the formation of a covalent intermediate. Next, a nucleophilic attack of Cys76 leads to the release of As(III) and the formation of a surface-exposed Cys74-Cys76 disulfide, ready for reduction by thioredoxin.


Asunto(s)
Arseniato Reductasas , Bacteroidetes , Dominio Catalítico , Oxidación-Reducción , Arseniato Reductasas/metabolismo , Arseniato Reductasas/genética , Arseniato Reductasas/química , Bacteroidetes/enzimología , Bacteroidetes/genética , Arseniatos/metabolismo , Cinética , Monoéster Fosfórico Hidrolasas/metabolismo , Monoéster Fosfórico Hidrolasas/genética , Monoéster Fosfórico Hidrolasas/química , Catálisis , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/química , Arsenitos/metabolismo
7.
Genome Res ; 32(1): 44-54, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34963662

RESUMEN

Genomic-scale somatic copy number alterations in healthy humans are difficult to investigate because of low occurrence rates and the structural variations' stochastic natures. Using a Tn5-transposase-assisted single-cell whole-genome sequencing method, we sequenced over 20,000 single lymphocytes from 16 individuals. Then, with the scale increased to a few thousand single cells per individual, we found that about 7.5% of the cells had large-size copy number alterations. Trisomy 21 was the most prevalent aneuploid event among all autosomal copy number alterations, whereas monosomy X occurred most frequently in over-30-yr-old females. In the monosomy X single cells from individuals with phased genomes and identified X-inactivation ratios in bulk, the inactive X Chromosomes were lost more often than the active ones.


Asunto(s)
Variaciones en el Número de Copia de ADN , Genómica , Aneuploidia , Femenino , Humanos , Linfocitos , Secuenciación Completa del Genoma
8.
EMBO Rep ; 24(6): e55764, 2023 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-37009823

RESUMEN

Mitochondrial ribosomal proteins (MRPs) assemble as specialized ribosome to synthesize mtDNA-encoded proteins, which are essential for mitochondrial bioenergetic and metabolic processes. MRPs are required for fundamental cellular activities during animal development, but their roles beyond mitochondrial protein translation are poorly understood. Here, we report a conserved role of the mitochondrial ribosomal protein L4 (mRpL4) in Notch signaling. Genetic analyses demonstrate that mRpL4 is required in the Notch signal-receiving cells to permit target gene transcription during Drosophila wing development. We find that mRpL4 physically and genetically interacts with the WD40 repeat protein wap and activates the transcription of Notch signaling targets. We show that human mRpL4 is capable of replacing fly mRpL4 during wing development. Furthermore, knockout of mRpL4 in zebrafish leads to downregulated expression of Notch signaling components. Thus, we have discovered a previously unknown function of mRpL4 during animal development.


Asunto(s)
Proteínas de Drosophila , Animales , Humanos , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Pez Cebra/genética , Pez Cebra/metabolismo , Receptores Notch/genética , Receptores Notch/metabolismo , Drosophila/genética , Proteínas Ribosómicas/genética , Proteínas Ribosómicas/metabolismo , Alas de Animales/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Regulación del Desarrollo de la Expresión Génica
9.
Exp Cell Res ; 439(2): 114099, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38802035

RESUMEN

Gastric cancer is histologically classified into the intestinal subtype, which forms tubular structures, and the aggressive diffuse subtype, characterized by rapid invasion and poor prognosis. The variety and quantity of miRNA isoforms between different histological subtypes of gastric cancer were unknown. Through systematic filtering, we found that more diverse miR-30a-5p isoforms was present in the diffuse subtype of gastric cancer, and was associated with patients' worse survival independent of tumor stage based on the TCGA miRNA-seq data. Among all nine isoforms of miR-30a-5p, miR-30a-5p -1|1 was more abundant than the archetype of miR-30a-5p. Higher expression of miR-30a-5p -1|1 was observed in patients with advanced tumor stage and poor survival. Furthermore, miR-30a-5p -1|1 could promote the metastasis of gastric cancer cells both in vitro and in vivo by down-regulating TMEM66. In clinical samples, decreased expression of TMEM66 was characteristic of gastric cancer, and the low level of TMEM66 correlated with deceased CD8 positive cells in the tumor microenvironment probably due to decreased cytokines production. In conclusion, the variety of miR-30a-5p isoforms correlates with worse survival in gastric cancer patients. Moreover, miR-30a-5p -1|1 could promote gastric cancer metastasis by inhibiting TMEM66 and the infiltration of intratumoral CD8 positive cells.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , Proteínas de la Membrana , MicroARNs , Neoplasias Gástricas , Linfocitos T Citotóxicos , Animales , Femenino , Humanos , Masculino , Ratones , Línea Celular Tumoral , Proliferación Celular/genética , Progresión de la Enfermedad , Regulación Neoplásica de la Expresión Génica/genética , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Ratones Desnudos , MicroARNs/genética , MicroARNs/metabolismo , Pronóstico , Neoplasias Gástricas/genética , Neoplasias Gástricas/patología , Neoplasias Gástricas/mortalidad , Neoplasias Gástricas/metabolismo , Linfocitos T Citotóxicos/inmunología , Linfocitos T Citotóxicos/metabolismo , Microambiente Tumoral/genética
10.
BMC Biol ; 22(1): 185, 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39218872

RESUMEN

BACKGROUND: Scutellaria, a sub-cosmopolitan genus, stands as one of the Lamiaceae family's largest genera, encompassing approximately 500 species found in both temperate and tropical montane regions. Recognized for its significant medicinal properties, this genus has garnered attention as a research focus, showcasing anti-cancer, anti-inflammatory, antioxidant, and hepatoprotective qualities. Additionally, it finds application in agriculture and horticulture. Comprehending Scutellaria's taxonomy is pivotal for its effective utilization and conservation. However, the current taxonomic frameworks, primarily based on morphological characteristics, are inadequate. Despite several phylogenetic studies, the species relationships and delimitations remain ambiguous, leaving the genus without a stable and reliable classification system. RESULTS: This study analyzed 234 complete chloroplast genomes, comprising 220 new and 14 previously published sequences across 206 species, subspecies, and varieties worldwide. Phylogenetic analysis was conducted using six data matrices through Maximum Likelihood and Bayesian Inference, resulting in a robustly supported phylogenetic framework for Scutellaria. We propose three subgenera, recommending the elevation of Section Anaspis to subgeneric rank and the merging of Sections Lupulinaria and Apeltanthus. The circumscription of Subgenus Apeltanthus and Section Perilomia needs to be reconsidered. Comparative analysis of chloroplast genomes highlighted the IR/SC boundary feature as a significant taxonomic indicator. We identified a total of 758 SSRs, 558 longer repetitive sequences, and ten highly variable regions, including trnK-rps16, trnC-petN, petN-psbM, accD-psaI, petA-psbJ, rpl32-trnL, ccsA-ndhD, rps15-ycf1, ndhF, and ycf1. These findings serve as valuable references for future research on species identification, phylogeny, and population genetics. CONCLUSIONS: The phylogeny of Scutellaria, based on the most comprehensive sample collection to date and complete chloroplast genome analysis, has significantly enhanced our understanding of its infrageneric relationships. The extensive examination of chloroplast genome characteristics establishes a solid foundation for the future development and utilization of Scutellaria, an important medicinal plant globally.


Asunto(s)
Genoma del Cloroplasto , Filogenia , Scutellaria , Scutellaria/genética
11.
Genomics ; 116(5): 110926, 2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39178997

RESUMEN

During sunflower growth, cold waves often occur and impede plant growth. Therefore, it is crucial to study the underlying mechanism of cold resistance in sunflowers. In this study, physiological analysis revealed that as cold stress increased, the levels of ROS, malondialdehyde, ascorbic acid, and dehydroascorbic acid and the activities of antioxidant enzymes increased. Transcriptomics further identified 10,903 DEGs between any two treatments. Clustering analysis demonstrated that the expression of MYB44a, MYB44b, MYB12, bZIP2 and bZIP4 continuously upregulated under cold stress. Cold stress can induce ROS accumulation, which interacts with hormone signals to activate cold-responsive transcription factors regulating target genes involved in antioxidant defense, secondary metabolite biosynthesis, starch and sucrose metabolism enhancement for improved cold resistance in sunflowers. Additionally, the response of sunflowers to cold stress may be independent of the CBF pathway. These findings enhance our understanding of cold stress resistance in sunflowers and provide a foundation for genetic breeding.

12.
Nano Lett ; 24(35): 10750-10758, 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39177063

RESUMEN

Membrane-active molecular machines represent a recently emerging, yet important line of expansion in the field of artificial transmembrane transporters. Their hitherto demonstrated limited types (molecular swing, ion fishers, shuttlers, rotors, etc.) certainly call for new inspiring developments. Here, we report a very first motorized ion-transporting carrier-type transporter, i.e., a modularly tunable, light-powered propeller-like transporter derived from Feringa's molecular motor for consistently boosting transmembrane ion transport under continuous UV light irradiation. Based on the EC50 values, the molecular propeller-mediated ion transport activities under UV light irradiation for 300 s are 2.31, 1.74, 2.29, 2.80, and 2.92 times those values obtained without irradiation for Li+, Na+, K+, Rb+, and Cs+ ions, respectively, with EC50 value as low as 0.71 mol % for K+ ion under light irradiation.

13.
Nano Lett ; 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39302876

RESUMEN

Artificial ionic sensory systems, bridging the divide between biological systems and electronics, mimic human skin functions but face critical challenges with biocompatibility, comfort, signal stability, and simplifying packaging. Here, we present a simple and permeable skin-interfaced iontronic mechanosensing (SIIM) architecture that integrates human skin as natural ionic material and hierarchically porous MXene-fiber composite membranes as sensing electrodes. The SIIM system eliminates complex ionic material design and multilayer matrix, exhibiting ultrahigh pressure sensitivities (5.4 kPa-1, <75 Pa), a low detection limit (6 Pa), excellent output stability along with high permeability to minimize the impact of sweating on sensing. The noncytotoxic nature of SIIM electrodes ensures excellent biocompatibility (>97% cell coincubational viability), facilitating long-term wearability and high biosafety. Furthermore, the scalable SIIM configuration integrated with matrix smart gloves, effectively monitors human physical movements. This SIIM-based sensor with marked sensing capabilities, structural simplicity, and scalability, holds promising potential in diverse wearable applications.

14.
Gut ; 73(10): 1618-1631, 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-38684238

RESUMEN

OBJECTIVE: Mutations in presenilin genes are the major cause of Alzheimer's disease. However, little is known about their expression and function in the gut. In this study, we identify the presenilins Psen1 and Psen2 as key molecules that maintain intestinal homoeostasis. DESIGN: Human inflammatory bowel disease (IBD) and control samples were analysed for Psen1 expression. Newly generated intestinal epithelium-specific Psen1-deficient, Psen2-deficient and inducible Psen1/Psen2 double-deficient mice were used to dissect the functional role of presenilins in intestinal homoeostasis. RESULTS: Psen1 expression was regulated in experimental gut inflammation and in patients with IBD. Induced deletion of Psen1 and Psen2 in mice caused rapid weight loss and spontaneous development of intestinal inflammation. Mice exhibited epithelial barrier disruption with bacterial translocation and deregulation of key pathways for nutrient uptake. Wasting disease was independent of gut inflammation and dysbiosis, as depletion of microbiota rescued Psen-deficient animals from spontaneous colitis development but not from weight loss. On a molecular level, intestinal epithelial cells lacking Psen showed impaired Notch signalling and dysregulated epithelial differentiation. CONCLUSION: Overall, our study provides evidence that Psen1 and Psen2 are important guardians of intestinal homoeostasis and future targets for barrier-promoting therapeutic strategies in IBD.


Asunto(s)
Enfermedad de Alzheimer , Homeostasis , Mucosa Intestinal , Presenilina-1 , Presenilina-2 , Animales , Ratones , Presenilina-2/genética , Presenilina-2/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/inmunología , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/genética , Humanos , Presenilina-1/genética , Enfermedades Inflamatorias del Intestino/inmunología , Enfermedades Inflamatorias del Intestino/metabolismo , Enfermedades Inflamatorias del Intestino/genética , Microbioma Gastrointestinal/fisiología , Ratones Noqueados , Células Epiteliales/metabolismo , Transducción de Señal , Disbiosis , Modelos Animales de Enfermedad
15.
Dev Biol ; 497: 59-67, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36907311

RESUMEN

The establishment of body pattern is a fundamental process in developmental biology. In Drosophila, the wing disc is subdivided into dorsal (D) and ventral (V) compartments by the D/V boundary. The dorsal fate is adopted by expressing the selector gene apterous (ap). ap expression is regulated by three combinational cis-regulatory modules which are activated by EGFR pathway, Ap-Vg auto-regulatory and epigenetic mechanisms. Here, we found that the Tbx family transcription factor Optomotor-blind (Omb) restricted ap expression in the ventral compartment. Loss of omb induced autonomous initiation of ap expression in the middle third instar larvae in the ventral compartment. Oppositely, over-activation of omb inhibited ap in the medial pouch. All three enhancers apE, apDV and apP were upregulated in omb null mutants, indicating a combinational regulation of ap modulators. However, Omb affected ap expression neither by directly regulating EGFR signaling, nor via Vg regulation. Therefore, a genetic screen of epigenetic regulators, including the Trithorax group (TrxG) and Polycomb group (PcG) genes was performed. We found that knocking down the TrxG gene kohtalo (kto), domino (dom) or expressing the PcG gene grainy head (grh), the ectopic ap in omb mutants was repressed. The inhibition of apDV by kto knockdown and grh activation could contribute to ap repression. Moreover, Omb and the EGFR pathway are genetically parallel in ap regulation in the ventral compartment. Collectively, Omb is a repressive signal for ap expression in the ventral compartment, which requires TrxG and PcG genes.


Asunto(s)
Proteínas de Drosophila , Proteínas del Tejido Nervioso , Factores de Transcripción , Animales , Proteínas de Unión al ADN/metabolismo , Drosophila/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Receptores ErbB/metabolismo , Regulación de la Expresión Génica , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Proteínas de Dominio T Box/genética , Proteínas de Dominio T Box/metabolismo , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Proteínas con Homeodominio LIM/genética , Proteínas con Homeodominio LIM/metabolismo
16.
J Am Chem Soc ; 146(17): 11855-11865, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38634945

RESUMEN

Creating structural defects in a controlled manner within metal-organic frameworks (MOFs) poses a significant challenge for synthesis, and concurrently, identifying the types and distributions of these defects is also a formidable task for characterization. In this study, we demonstrate that by employing 2-sulfonylterephthalic acid as the ligand for synthesizing Zr (or Hf)-based MOFs, a crystal phase transformation from the common fcu topology to the rare jmt topology can be easily facilitated using a straightforward mixed-solvent strategy. The jmt phase, characterized by an extensively open framework, can be considered a derivative of the fcu phase, generated through the introduction of missing-cluster defects. We have explicitly identified both MOF phases, their intermediate states, and the novel core-shell structures they form using ultralow-dose high-resolution transmission electron microscopy. In addition to facilitating phase engineering, the incorporation of sulfonic groups in MOFs imparts ionic selectivity, making them applicable for osmotic energy harvesting through mixed matrix membrane fabrication. The membrane containing the jmt-phase MOF exhibits an exceptionally high peak power density of 10.08 W m-2 under a 50-fold salinity gradient (NaCl: 0.5 M|0.01 M), which surpasses the threshold of 5 W m-2 for commercial applications and can be attributed to the combination of large pore size, extensive porosity, and abundant sulfonic groups in this novel MOF material.

17.
Eur J Neurosci ; 60(4): 4569-4585, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38992988

RESUMEN

The involvement of inwardly rectifying potassium channel 4.1 (Kir4.1) in neuropathic pain has been established. However, there is limited understanding of the downstream mechanism through which Kir4.1 contributes to orofacial neuropathic pain. The objective of this study was to examine the regulation of Kir4.1 on the expression of pannexin 3 (Panx3) in the trigeminal ganglion (TG) and the underlying mechanism in the context of orofacial neuropathic pain caused by chronic constriction injury of the infraorbital nerve (CCI-ION). The study observed a significant increase in Panx3 expression in the TG of mice with CCI-ION. Inhibition of Panx3 in the TG of CCI-ION mice resulted in alleviation of orofacial mechanical allodynia. Furthermore, conditional knockdown (CKD) of Kir4.1 in the TG of both male and female mice led to mechanical allodynia and upregulation of Panx3 expression. Conversely, overexpression of Kir4.1 decreased Panx3 levels in the TG and relieved mechanical allodynia in CCI-ION mice. In addition, silencing Kir4.1 in satellite glial cells (SGCs) decreased Panx3 expression and increased the phosphorylation of P38 MAPK. Moreover, silencing Kir4.1 in SGCs increased the levels of reactive oxygen species (ROS). The elevated phosphorylation of P38 MAPK resulting from Kir4.1 silencing was inhibited by using a superoxide scavenger known as the tempol. Silencing Panx3 in the TG in vivo attenuated the mechanical allodynia caused by Kir4.1 CKD. In conclusion, these findings suggest that the reduction of Kir4.1 promotes the expression of Panx3 by activating the ROS-P38 MAPK signalling pathway, thus contributing to the development of orofacial neuropathic pain.


Asunto(s)
Conexinas , Neuralgia , Especies Reactivas de Oxígeno , Proteínas Quinasas p38 Activadas por Mitógenos , Animales , Femenino , Masculino , Ratones , Conexinas/metabolismo , Conexinas/genética , Dolor Facial/metabolismo , Hiperalgesia/metabolismo , Sistema de Señalización de MAP Quinasas/fisiología , Ratones Endogámicos C57BL , Proteínas del Tejido Nervioso/metabolismo , Proteínas del Tejido Nervioso/genética , Neuralgia/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Canales de Potasio de Rectificación Interna/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Ganglio del Trigémino/metabolismo , Proteína Quinasa 14 Activada por Mitógenos/metabolismo
18.
Biochem Biophys Res Commun ; 733: 150709, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39303526

RESUMEN

SLC16A3/monocarboxylate transporter 4 (MCT4) regulates intracellular lactate transport and is highly expressed in many tumors, indicating poor prognosis. It may be related to inducing hypoxia, apoptosis and other mechanisms, but the study of MCT4 in HCC is far from complete. In this study, we first analyzed the expression of SLC16A3 in HCC tumor and non-tumor tissue samples based on TCGA data and immunohistochemistry. Subsequently, the effects of SLC16A3 expression on cell proliferation and invasion were analyzed using hepatocellular carcinoma (HCC) lines, and Western blot (WB) analysis was performed to explore the changes in pathway proteins and ferroptosis proteins. Finally, the drug sensitivity was tested by CCK8 kit. We found that SLC16A3 was significantly upregulated in tumor tissues, and was significantly correlated with TNM stage, histological grade, and macrovascular invasion. TCGA data and WB analysis showed that the high expression of SLC16A3 induced hypoxia, and knockdown could reverse hypoxia and inhibit ERK phosphorylation, thus limiting the malignant behavior of HCC cells. Moreover, knockdown of SLC16A3 significantly increased the level of lipid peroxidation and reactive oxygen species (ROS), while the expressions of GPX4, DHODH and SLC7A11 were inhibited. The expression of SLC16A3 affected the sensitivity of HCC cells to chemotherapy and targeted drugs, and RNA sequencing data suggested that the expression level influenced tumor microenvironment and response to immunotherapy. So, we draw a conclude that SLC16A3 is associated with poor prognosis of HCC. Inhibition of SLC16A3 expression is a potential therapeutic target for HCC.

19.
BMC Plant Biol ; 24(1): 792, 2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39169292

RESUMEN

BACKGROUND: With the progress of industrialization and urbanization, cadmium (Cd) pollution in farmland is increasingly severe, greatly affecting human health. Sunflowers possess high resistance to Cd stress and great potential for phytoremediation of Cd-contaminated soil. Previous studies have shown that humic acid (HA) effectively mitigates plant damage induced by Cd; however, its alleviating effects on sunflower plants under Cd stress remain largely unknown. RESULTS: We employed four different concentrations of HA (50, 100, 200, and 300 mg L-1) via foliar application to examine their ability to alleviate Cd stress on sunflower plants' growth, chlorophyll synthesis, and biochemical defense system. The results revealed that Cd stress not only reduced plant height, stem diameter, fresh and dry weight, and chlorophyll content in sunflower plants but also altered their chlorophyll fluorescence characteristics compared to the control group. After Cd stress, the photosynthetic structure was damaged and the number of PSII reactive centers per unit changed. Application of 200 mg L-1 HA promotes sunflower growth and increases chlorophyll content. HA significantly enhances antioxidant enzyme activities (SOD, POD, CAT, and APX) and reduces ROS content (O2 -, H2O2 and -OH). Totally, Application of 200 mg L-1 HA had the best effect than other concentrations to alleviate the Cd-induced stress in sunflower plants. CONCLUSIONS: The foliar application of certain HA concentration exhibited the most effective alleviation of Cd-induced stress on sunflower plants. It can enhance the light energy utilization and antioxidant enzyme activities, while reduce ROS contents in sunflower plants. These findings provide a theoretical basis for using HA to mitigate Cd stress in sunflowers.


Asunto(s)
Cadmio , Clorofila , Helianthus , Sustancias Húmicas , Clorofila/metabolismo , Helianthus/efectos de los fármacos , Helianthus/metabolismo , Helianthus/crecimiento & desarrollo , Hojas de la Planta/metabolismo , Hojas de la Planta/efectos de los fármacos , Estrés Fisiológico , Biodegradación Ambiental , Contaminantes del Suelo , Fotosíntesis/efectos de los fármacos , Antioxidantes/metabolismo , Especies Reactivas de Oxígeno/metabolismo
20.
J Neurosci Res ; 102(1): e25293, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38284838

RESUMEN

Neurovascular coupling (NVC) provides new insights into migraine, a neurological disorder impacting over one billion people worldwide. This study compared NVC and cerebral blood flow (CBF) in patients with migraine without aura (MwoA) and healthy controls. About 55 MwoA patients in the interictal phase and 40 age- and sex-matched healthy controls underwent resting-state functional magnetic resonance imaging and arterial spin-labeling perfusion imaging scans. The CBF and resting-state neuronal activity indicators, including the amplitudes of low-frequency fluctuation (ALFF), regional homogeneity (ReHo), and degree centrality (DC), were calculated for each participant. The global and regional NVCs were assessed using cross-voxel CBF-neuronal activity correlations and CBF/neuronal activity ratios. Patients with MwoA showed increased CBF/ALFF ratios in the left media, superior and inferior frontal gyri, and anterior cingulate gyrus, increased CBF/DC ratios in the left middle and inferior frontal gyri, and increased CBF/ReHo ratios in the right corpus callosum and right posterior cingulate gyrus. Lower CBF/ALFF ratios in the right rectal gyrus, the left orbital gyrus, the right inferior frontal gyrus, and the right superior temporal gyrus were also found in the MwoA patients. Furthermore, the CBF/ALFF ratios in the inferior frontal and superior temporal gyri were positively correlated with the Headache Impact Test scores and Hamilton anxiety scale scores in the MwoA patients. These findings provide evidence for the theory that abnormal NVC contributes to MwoA.


Asunto(s)
Migraña sin Aura , Acoplamiento Neurovascular , Humanos , Migraña sin Aura/diagnóstico por imagen , Circulación Cerebrovascular , Lóbulo Frontal , Cuerpo Calloso
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