Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.751
Filtrar
Más filtros

Tipo del documento
Intervalo de año de publicación
1.
Cell ; 173(3): 677-692.e20, 2018 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-29677512

RESUMEN

RNA-binding proteins (RBPs) with prion-like domains (PrLDs) phase transition to functional liquids, which can mature into aberrant hydrogels composed of pathological fibrils that underpin fatal neurodegenerative disorders. Several nuclear RBPs with PrLDs, including TDP-43, FUS, hnRNPA1, and hnRNPA2, mislocalize to cytoplasmic inclusions in neurodegenerative disorders, and mutations in their PrLDs can accelerate fibrillization and cause disease. Here, we establish that nuclear-import receptors (NIRs) specifically chaperone and potently disaggregate wild-type and disease-linked RBPs bearing a NLS. Karyopherin-ß2 (also called Transportin-1) engages PY-NLSs to inhibit and reverse FUS, TAF15, EWSR1, hnRNPA1, and hnRNPA2 fibrillization, whereas Importin-α plus Karyopherin-ß1 prevent and reverse TDP-43 fibrillization. Remarkably, Karyopherin-ß2 dissolves phase-separated liquids and aberrant fibrillar hydrogels formed by FUS and hnRNPA1. In vivo, Karyopherin-ß2 prevents RBPs with PY-NLSs accumulating in stress granules, restores nuclear RBP localization and function, and rescues degeneration caused by disease-linked FUS and hnRNPA2. Thus, NIRs therapeutically restore RBP homeostasis and mitigate neurodegeneration.


Asunto(s)
Transporte Activo de Núcleo Celular , Priones/química , Proteínas de Unión al ARN/química , Receptores Citoplasmáticos y Nucleares/química , Adulto , Anciano , Animales , Citoplasma/química , Proteínas de Unión al ADN/química , Drosophila melanogaster , Femenino , Proteínas Fluorescentes Verdes/química , Células HEK293 , Células HeLa , Homeostasis , Humanos , Carioferinas/química , Masculino , Persona de Mediana Edad , Chaperonas Moleculares/química , Mutación , Enfermedades Neurodegenerativas/patología , Dominios Proteicos , Proteína EWS de Unión a ARN/química , Factores Asociados con la Proteína de Unión a TATA/química , beta Carioferinas/química
2.
Nat Immunol ; 20(1): 18-28, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30510222

RESUMEN

Cyclic GMP-AMP synthase (cGAS) is a key sensor responsible for cytosolic DNA detection. Here we report that GTPase-activating protein SH3 domain-binding protein 1 (G3BP1) is critical for DNA sensing and efficient activation of cGAS. G3BP1 enhanced DNA binding of cGAS by promoting the formation of large cGAS complexes. G3BP1 deficiency led to inefficient DNA binding by cGAS and inhibited cGAS-dependent interferon (IFN) production. The G3BP1 inhibitor epigallocatechin gallate (EGCG) disrupted existing G3BP1-cGAS complexes and inhibited DNA-triggered cGAS activation, thereby blocking DNA-induced IFN production both in vivo and in vitro. EGCG administration blunted self DNA-induced autoinflammatory responses in an Aicardi-Goutières syndrome (AGS) mouse model and reduced IFN-stimulated gene expression in cells from a patient with AGS. Thus, our study reveals that G3BP1 physically interacts with and primes cGAS for efficient activation. Furthermore, EGCG-mediated inhibition of G3BP1 provides a potential treatment for cGAS-related autoimmune diseases.


Asunto(s)
Enfermedades Autoinmunes del Sistema Nervioso/metabolismo , ADN Helicasas/metabolismo , Complejos Multiproteicos/metabolismo , Malformaciones del Sistema Nervioso/metabolismo , Nucleotidiltransferasas/metabolismo , Proteínas de Unión a Poli-ADP-Ribosa/metabolismo , ARN Helicasas/metabolismo , Proteínas con Motivos de Reconocimiento de ARN/metabolismo , Animales , Autoantígenos/inmunología , Autoantígenos/metabolismo , Enfermedades Autoinmunes del Sistema Nervioso/tratamiento farmacológico , Enfermedades Autoinmunes del Sistema Nervioso/genética , Catequina/análogos & derivados , Catequina/uso terapéutico , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas , Citosol/inmunología , Citosol/metabolismo , ADN/inmunología , ADN/metabolismo , ADN Helicasas/antagonistas & inhibidores , ADN Helicasas/genética , Modelos Animales de Enfermedad , Exodesoxirribonucleasas/genética , Células HEK293 , Células HeLa , Humanos , Interferones/metabolismo , Ratones , Ratones Noqueados , Malformaciones del Sistema Nervioso/tratamiento farmacológico , Malformaciones del Sistema Nervioso/genética , Fármacos Neuroprotectores/uso terapéutico , Fosfoproteínas/genética , Proteínas de Unión a Poli-ADP-Ribosa/antagonistas & inhibidores , Proteínas de Unión a Poli-ADP-Ribosa/genética , Unión Proteica , ARN Helicasas/antagonistas & inhibidores , ARN Helicasas/genética , Proteínas con Motivos de Reconocimiento de ARN/antagonistas & inhibidores , Proteínas con Motivos de Reconocimiento de ARN/genética
3.
Cell ; 162(2): 287-299, 2015 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-26165940

RESUMEN

Spindle assembly requires the coordinated action of multiple cellular structures to nucleate and organize microtubules in a precise spatiotemporal manner. Among them, the contributions of centrosomes, chromosomes, and microtubules have been well studied, yet the involvement of membrane-bound organelles remains largely elusive. Here, we provide mechanistic evidence for a membrane-based, Golgi-derived microtubule assembly pathway in mitosis. Upon mitotic entry, the Golgi matrix protein GM130 interacts with importin α via a classical nuclear localization signal that recruits importin α to the Golgi membranes. Sequestration of importin α by GM130 liberates the spindle assembly factor TPX2, which activates Aurora-A kinase and stimulates local microtubule nucleation. Upon filament assembly, nascent microtubules are further captured by GM130, thus linking Golgi membranes to the spindle. Our results reveal an active role for the Golgi in regulating spindle formation to ensure faithful organelle inheritance.


Asunto(s)
Autoantígenos/metabolismo , Proteínas de Ciclo Celular/metabolismo , Aparato de Golgi/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas Asociadas a Microtúbulos/metabolismo , Proteínas Nucleares/metabolismo , Animales , Aurora Quinasa A/metabolismo , Células HeLa , Humanos , Carioferinas/metabolismo , Ratones , Microtúbulos/metabolismo , Mitosis , Fosfoproteínas/metabolismo , Huso Acromático , Xenopus/metabolismo , Proteínas de Xenopus/metabolismo
4.
Nature ; 629(8011): 363-369, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38547926

RESUMEN

Cytochrome P450 enzymes are known to catalyse bimodal oxidation of aliphatic acids via radical intermediates, which partition between pathways of hydroxylation and desaturation1,2. Developing analogous catalytic systems for remote C-H functionalization remains a significant challenge3-5. Here, we report the development of Cu(I)-catalysed bimodal dehydrogenation/lactonization reactions of synthetically common N-methoxyamides through radical abstractions of the γ-aliphatic C-H bonds. The feasibility of switching from dehydrogenation to lactonization is also demonstrated by altering reaction conditions. The use of a readily available amide as both radical precursor and internal oxidant allows for the development of redox-neutral C-H functionalization reactions with methanol as the sole side product. These C-H functionalization reactions using a Cu(I) catalyst with loading as low as 0.5 mol.% is applied to the diversification of a wide range of aliphatic acids including drug molecules and natural products. The exceptional compatibility of this catalytic system with a wide range of oxidatively sensitive functionality demonstrates the unique advantage of using a simple amide substrate as a mild internal oxidant.


Asunto(s)
Carbono , Cobre , Hidrógeno , Lactonas , Amidas/química , Amidas/metabolismo , Carbono/química , Catálisis , Cobre/química , Sistema Enzimático del Citocromo P-450/metabolismo , Sistema Enzimático del Citocromo P-450/química , Hidrógeno/química , Hidrogenación , Lactonas/química , Metanol/química , Oxidantes/química , Oxidantes/metabolismo , Oxidación-Reducción
5.
Mol Cell ; 81(7): 1425-1438.e10, 2021 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-33662272

RESUMEN

Eukaryotic elongation factor 2 (eEF2) mediates translocation of peptidyl-tRNA from the ribosomal A site to the P site to promote translational elongation. Its phosphorylation on Thr56 by its single known kinase eEF2K inactivates it and inhibits translational elongation. Extensive studies have revealed that different signal cascades modulate eEF2K activity, but whether additional factors regulate phosphorylation of eEF2 remains unclear. Here, we find that the X chromosome-linked intellectual disability protein polyglutamine-binding protein 1 (PQBP1) specifically binds to non-phosphorylated eEF2 and suppresses eEF2K-mediated phosphorylation at Thr56. Loss of PQBP1 significantly reduces general protein synthesis by suppressing translational elongation. Moreover, we show that PQBP1 regulates hippocampal metabotropic glutamate receptor-dependent long-term depression (mGluR-LTD) and mGluR-LTD-associated behaviors by suppressing eEF2K-mediated phosphorylation. Our results identify PQBP1 as a novel regulator in translational elongation and mGluR-LTD, and this newly revealed regulator in the eEF2K/eEF2 pathway is also an excellent therapeutic target for various disease conditions, such as neural diseases, virus infection, and cancer.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Hipocampo/metabolismo , Depresión Sináptica a Largo Plazo , Extensión de la Cadena Peptídica de Translación , Factor 2 de Elongación Peptídica/metabolismo , Receptores de Glutamato Metabotrópico/biosíntesis , Animales , Proteínas de Unión al ADN/genética , Células HEK293 , Células HeLa , Humanos , Ratones , Ratones Noqueados , Factor 2 de Elongación Peptídica/genética , Fosforilación , Receptores de Glutamato Metabotrópico/genética
6.
Cell ; 153(5): 1012-24, 2013 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-23706739

RESUMEN

Histone acetylation plays critical roles in chromatin remodeling, DNA repair, and epigenetic regulation of gene expression, but the underlying mechanisms are unclear. Proteasomes usually catalyze ATP- and polyubiquitin-dependent proteolysis. Here, we show that the proteasomes containing the activator PA200 catalyze the polyubiquitin-independent degradation of histones. Most proteasomes in mammalian testes ("spermatoproteasomes") contain a spermatid/sperm-specific α subunit α4 s/PSMA8 and/or the catalytic ß subunits of immunoproteasomes in addition to PA200. Deletion of PA200 in mice abolishes acetylation-dependent degradation of somatic core histones during DNA double-strand breaks and delays core histone disappearance in elongated spermatids. Purified PA200 greatly promotes ATP-independent proteasomal degradation of the acetylated core histones, but not polyubiquitinated proteins. Furthermore, acetylation on histones is required for their binding to the bromodomain-like regions in PA200 and its yeast ortholog, Blm10. Thus, PA200/Blm10 specifically targets the core histones for acetylation-mediated degradation by proteasomes, providing mechanisms by which acetylation regulates histone degradation, DNA repair, and spermatogenesis.


Asunto(s)
Reparación del ADN , Histonas/metabolismo , Proteínas Nucleares/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo , Espermatogénesis , Testículo/metabolismo , Acetilación , Secuencia de Aminoácidos , Animales , Roturas del ADN de Doble Cadena , Humanos , Masculino , Ratones , Datos de Secuencia Molecular , Proteínas Nucleares/química , Estructura Terciaria de Proteína , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Alineación de Secuencia
7.
EMBO Rep ; 25(2): 770-795, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38182816

RESUMEN

DExD/H-box helicases are crucial regulators of RNA metabolism and antiviral innate immune responses; however, their role in bacteria-induced inflammation remains unclear. Here, we report that DDX5 interacts with METTL3 and METTL14 to form an m6A writing complex, which adds N6-methyladenosine to transcripts of toll-like receptor (TLR) 2 and TLR4, promoting their decay via YTHDF2-mediated RNA degradation, resulting in reduced expression of TLR2/4. Upon bacterial infection, DDX5 is recruited to Hrd1 at the endoplasmic reticulum in an MyD88-dependent manner and is degraded by the ubiquitin-proteasome pathway. This process disrupts the DDX5 m6A writing complex and halts m6A modification as well as degradation of TLR2/4 mRNAs, thereby promoting the expression of TLR2 and TLR4 and downstream NF-κB activation. The role of DDX5 in regulating inflammation is also validated in vivo, as DDX5- and METTL3-KO mice exhibit enhanced expression of inflammatory cytokines. Our findings show that DDX5 acts as a molecular switch to regulate inflammation during bacterial infection and shed light on mechanisms of quiescent inflammation during homeostasis.


Asunto(s)
Adenina , Infecciones Bacterianas , Receptor Toll-Like 2 , Animales , Ratones , Adenina/análogos & derivados , Inflamación/genética , Metiltransferasas/genética , Receptor Toll-Like 2/genética , Receptor Toll-Like 4/genética
8.
Brief Bioinform ; 24(2)2023 03 19.
Artículo en Inglés | MEDLINE | ID: mdl-36847697

RESUMEN

Brain imaging genomics is an emerging interdisciplinary field, where integrated analysis of multimodal medical image-derived phenotypes (IDPs) and multi-omics data, bridging the gap between macroscopic brain phenotypes and their cellular and molecular characteristics. This approach aims to better interpret the genetic architecture and molecular mechanisms associated with brain structure, function and clinical outcomes. More recently, the availability of large-scale imaging and multi-omics datasets from the human brain has afforded the opportunity to the discovering of common genetic variants contributing to the structural and functional IDPs of the human brain. By integrative analyses with functional multi-omics data from the human brain, a set of critical genes, functional genomic regions and neuronal cell types have been identified as significantly associated with brain IDPs. Here, we review the recent advances in the methods and applications of multi-omics integration in brain imaging analysis. We highlight the importance of functional genomic datasets in understanding the biological functions of the identified genes and cell types that are associated with brain IDPs. Moreover, we summarize well-known neuroimaging genetics datasets and discuss challenges and future directions in this field.


Asunto(s)
Encéfalo , Genómica , Humanos , Genómica/métodos , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Fenotipo , Neuroimagen/métodos
9.
Mol Ther ; 32(8): 2778-2797, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-38822524

RESUMEN

Dysregulated T cell activation underpins the immunopathology of rheumatoid arthritis (RA), yet the machineries that orchestrate T cell effector program remain incompletely understood. Herein, we leveraged bulk and single-cell RNA sequencing data from RA patients and validated protein disulfide isomerase family A member 3 (PDIA3) as a potential therapeutic target. PDIA3 is remarkably upregulated in pathogenic CD4 T cells derived from RA patients and positively correlates with C-reactive protein level and disease activity score 28. Pharmacological inhibition or genetic ablation of PDIA3 alleviates RA-associated articular pathology and autoimmune responses. Mechanistically, T cell receptor signaling triggers intracellular calcium flux to activate NFAT1, a process that is further potentiated by Wnt5a under RA settings. Activated NFAT1 then directly binds to the Pdia3 promoter to enhance the expression of PDIA3, which complexes with STAT1 or PKM2 to facilitate their nuclear import for transcribing T helper 1 (Th1) and Th17 lineage-related genes, respectively. This non-canonical regulatory mechanism likely occurs under pathological conditions, as PDIA3 could only be highly induced following aberrant external stimuli. Together, our data support that targeting PDIA3 is a vital strategy to mitigate autoimmune diseases, such as RA, in clinical settings.


Asunto(s)
Artritis Reumatoide , Proteína Disulfuro Isomerasas , Factor de Transcripción STAT1 , Proteína Disulfuro Isomerasas/metabolismo , Proteína Disulfuro Isomerasas/genética , Humanos , Artritis Reumatoide/metabolismo , Ratones , Animales , Factor de Transcripción STAT1/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/genética , Transporte Activo de Núcleo Celular , Proteínas Portadoras/metabolismo , Transducción de Señal , Proteínas de Unión a Hormona Tiroide , Factores de Transcripción NFATC/metabolismo , Activación de Linfocitos , Hormonas Tiroideas/metabolismo , Regulación de la Expresión Génica , Células Th17/metabolismo , Células Th17/inmunología , Células TH1/inmunología , Células TH1/metabolismo , Modelos Animales de Enfermedad , Piruvato Quinasa
10.
Proc Natl Acad Sci U S A ; 119(20): e2200155119, 2022 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-35561211

RESUMEN

Glucagon-like peptide-1 receptor (GLP-1R) agonists are effective in treating type 2 diabetes and obesity with proven cardiovascular benefits. However, most of these agonists are peptides and require subcutaneous injection except for orally available semaglutide. Boc5 was identified as the first orthosteric nonpeptidic agonist of GLP-1R that mimics a broad spectrum of bioactivities of GLP-1 in vitro and in vivo. Here, we report the cryoelectron microscopy structures of Boc5 and its analog WB4-24 in complex with the human GLP-1R and Gs protein. Bound to the extracellular domain, extracellular loop 2, and transmembrane (TM) helices 1, 2, 3, and 7, one arm of both compounds was inserted deeply into the bottom of the orthosteric binding pocket that is usually accessible by peptidic agonists, thereby partially overlapping with the residues A8 to D15 in GLP-1. The other three arms, meanwhile, extended to the TM1-TM7, TM1-TM2, and TM2-TM3 clefts, showing an interaction feature substantially similar to the previously known small-molecule agonist LY3502970. Such a unique binding mode creates a distinct conformation that confers both peptidomimetic agonism and biased signaling induced by nonpeptidic modulators at GLP-1R. Further, the conformational difference between Boc5 and WB4-24, two closed related compounds, provides a structural framework for fine-tuning of pharmacological efficacy in the development of future small-molecule therapeutics targeting GLP-1R.


Asunto(s)
Ciclobutanos , Receptor del Péptido 1 Similar al Glucagón , Peptidomiméticos , Microscopía por Crioelectrón , Ciclobutanos/química , Ciclobutanos/farmacología , Receptor del Péptido 1 Similar al Glucagón/agonistas , Receptor del Péptido 1 Similar al Glucagón/química , Humanos , Peptidomiméticos/química , Peptidomiméticos/farmacología , Dominios Proteicos
11.
J Cell Physiol ; : e31393, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39210747

RESUMEN

AMP-activated protein kinase (AMPK), a crucial regulatory kinase, monitors energy levels, conserving ATP and boosting synthesis in low-nutrition, low-energy states. Its sensitivity links microenvironmental changes to cellular responses. As the primary support structure and endocrine organ, the maintenance, and repair of bones are closely associated with the microenvironment. While a series of studies have explored the effects of specific microenvironments on bone, there is lack of angles to comprehensively evaluate the interactions between microenvironment and bone cells, especially for bone marrow mesenchymal stem cells (BMMSCs) which mediate the differentiation of osteogenic lineage. It is noteworthy that accumulating evidence has indicated that AMPK may serve as a hub between BMMSCs and microenvironment factors, thus providing a new perspective for us to understand the biology and pathophysiology of stem cells and bone. In this review, we emphasize AMPK's pivotal role in bone microenvironment modulation via ATP, inflammation, reactive oxygen species (ROS), calcium, and glucose, particularly in BMMSCs. We further explore the use of AMPK-activating drugs in the context of osteoarthritis and osteoporosis. Moreover, building upon the foundation of AMPK, we elucidate a viewpoint that facilitates a comprehensive understanding of the dynamic relationship between the microenvironment and bone homeostasis, offering valuable insights for prospective investigations into stem cell biology and the treatment of bone diseases.

12.
J Am Chem Soc ; 146(15): 10776-10784, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38578219

RESUMEN

Seeking noble-metal-free catalysts for efficient synthesis of aryl nitriles under mild conditions poses a significant challenge due to the use of hypertoxic cyanides or high-pressure/temperature NH3/O2 in conventional synthesis processes. Herein, we developed a novel framework 1 assembled by [Ni72] nanocages with excellent solvents/pH stability. To investigate the structure-activity relationship of catalytic performance, several isostructural MOFs with different molar ratios of Ni/Cu by doping Cu2+ into framework 1 (Ni0.59Cu0.41 (2), Ni0.81Cu0.19 (3), Ni0.88Cu0.12 (4), and Ni0.92Cu0.08 (5)) were prepared. Catalytic studies revealed that catalyst 3 exhibited remarkable performance in the synthesis of aryl nitriles, utilizing a formamide alternative to hypertoxic NaCN/KCN. Notably, catalyst 3 achieved an excellent TOF value of 9.8 h-1. Furthermore, catalyst 3 demonstrated its applicability in a gram-scale experiment and maintained its catalytic performance even after six recycling cycles, owing to its high stability resulting from significant electrostatic and orbital interactions between the Ni center and ligands as well as a large SOMO-LUMO energy gap supported by DFT calculations. Control experiments and DFT calculations further revealed that the excellent catalytic performance of catalyst 3 originated from the synergistic effect of Ni/Cu. Importantly, this work not only provides a highly feasible method to construct highly stable MOFs containing multinuclear nanocages with exceptional catalytic performance but also represents the first example of a heterogeneous catalyst for the synthesis of aryl nitriles using formamide as the cyanide source.

13.
J Am Chem Soc ; 146(13): 9172-9180, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38514382

RESUMEN

The catalytic asymmetric construction of axially chiral C-N atropisomers remains a formidable challenge due to their low rotational barriers and is largely reliant on toxic, cost-intensive, and precious metal catalysts. In sharp contrast, we herein describe the first nickel-catalyzed atroposelective C-H alkylation for the construction of C-N axially chiral compounds with the aid of a chiral heteroatom-substituted secondary phosphine oxide (HASPO)-ligated Ni-Al bimetallic catalyst. A wide range of alkenes, including terminal and internal alkenes, were well compatible with the reaction, providing a variety of benzimidazole derivatives in high yields and enantioselectivities (up to 97:3 e.r.). The key to success was the identification of novel HASPOs as highly effective chiral preligands. Mechanistic studies revealed the catalyst mode of action, and in-depth data science analysis elucidated the key features of the responsible chiral preligands in controlling the enantioselectivity.

14.
J Am Chem Soc ; 146(12): 8206-8215, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38412246

RESUMEN

Spin-crossover (SCO) materials exhibit remarkable potential as bistable switches in molecular devices. However, the spin transition temperatures (Tc) of known compounds are unable to cover the entire ambient temperature spectrum, largely limiting their practical utility. This study reports an exemplary two-dimensional SCO solid solution system, [FeIII(H0.5LCl)2-2x(H0.5LF)2x]·H2O (H0.5LX = 5-X-2-hydroxybenzylidene-hydrazinecarbothioamide, X = F or Cl, x = 0 to 1), in which the adjacent layers are adhered via hydrogen bonding. Notably, the Tc of this system can be fine-tuned across 90 K (227-316 K) in a linear manner by modulating the fraction x of the LF ligand. Elevating x results in strengthened hydrogen bonding between adjacent layers, which leads to enhanced intermolecular interactions between adjacent SCO molecules. Single-crystal diffraction analysis and periodic density functional theory calculations revealed that such a special kind of alteration in interlayer interactions strengthens the FeIIIN2O2S2 ligand field and corresponding SCO energy barrier, consequently resulting in increased Tc. This work provides a new pathway for tuning the Tc of SCO materials through delicate manipulation of molecular interactions, which could expand the application of bistable molecular solids to a much wider temperature regime.

15.
Mol Biol Evol ; 40(1)2023 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-36625089

RESUMEN

Determining the functional consequences of karyotypic changes is invariably challenging because evolution tends to obscure many of its own footprints, such as accumulated mutations, recombination events, and demographic perturbations. Here, we describe the assembly of a chromosome-level reference genome of the gayal (Bos frontalis) thereby revealing the structure, at base-pair-level resolution, of a telo/acrocentric-to-telo/acrocentric Robertsonian translocation (2;28) (T/A-to-T/A rob[2;28]). The absence of any reduction in the recombination rate or genetic introgression within the fusion region of gayal served to challenge the long-standing view of a role for fusion-induced meiotic dysfunction in speciation. The disproportionate increase noted in the distant interactions across pro-chr2 and pro-chr28, and the change in open-chromatin accessibility following rob(2;28), may, however, have led to the various gene expression irregularities observed in the gayal. Indeed, we found that many muscle-related genes, located synthetically on pro-chr2 and pro-chr28, exhibited significant changes in expression. This, combined with genome-scale structural variants and expression alterations in genes involved in myofibril composition, may have driven the rapid sarcomere adaptation of gayal to its rugged mountain habitat. Our findings not only suggest that large-scale chromosomal changes can lead to alterations in genome-level expression, thereby promoting both adaptation and speciation, but also illuminate novel avenues for studying the relationship between karyotype evolution and speciation.


Asunto(s)
Cromatina , Genoma , Animales , Bovinos
16.
Anal Chem ; 96(35): 14265-14273, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39167707

RESUMEN

Nonylphenol (NP) is an important fine chemical raw material and intermediate that is widely utilized in industry and may be distributed in aquatic ecosystems. Following its entry into the food and water cycles, it can subsequently enter the human body and potentially harm the human reproductive system. For the purpose of monitoring NP in water, it is thus essential to build a straightforward, affordable, and robust electrochemical sensor. Based on a two-step chemical modification proceeding and an electrostatic self-assembly effect, a double-modified ß-cyclodextrin functionalized multiwalled carbon nanotube sensor (HE-ß-CD-CTAC/F-MWCNTs) has been successfully constructed. It incorporates the excellent host-guest interaction ability of ß-cyclodextrin and the high chemical activity of cetyltrimethylammonium chloride (CTAC), and the carbon nanotubes have an enormous particular surface area and strong electrical conductivity. The electrochemical oxidation reaction of NP with the sensor is controlled by a surface adsorption process of equal numbers of protons and electrons. In accordance with the optimized experimental parameters, the limit of detection (LOD) for the sensor is 0.13 µM, and it responds linearly to NP in the concentration range of 1-200 µM. Meanwhile, the sensor has excellent repeatability, stability, and immunity to interference. For the detection of NP in real water samples, the sensor also showed an excellent recovery rate (92.8%-98.5%) and relative standard deviation (1.16%-3.26%).

17.
Biochem Biophys Res Commun ; 733: 150614, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39276692

RESUMEN

The incidence of myopia, particularly high myopia, is increasing annually. Myopia has gradually become one of the leading causes of global blindness and is a considerable public-health concern. However, the pathogenesis of myopia remains unclear, and exploring the mechanism underlying myopia has become an urgent scientific priority. Creating animal models of myopia is important for studying the pathogenesis of refractive errors. This approach allows researchers to study and analyze the pathogenesis of myopia from aspects such as changes in refractive development, pathological changes in eye tissue, and molecular pathways related to myopia. This review summarizes the examples of animal models, methods of inducing myopia experimentally, and molecular signaling pathways involved in developing myopia-induced animal models. This review provides solid literature for researchers in the field of myopia prevention and control. It offers guidance in selecting appropriate animal models and research methods to fit their research objectives. By providing new insights and a theoretical basis for studying mechanisms of myopia, we detail how elucidated molecular pathways can be exploited to translate into safe and effective measures for myopia prevention and control.

18.
Biochem Biophys Res Commun ; 734: 150662, 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39245030

RESUMEN

Lipid metabolism, particularly triglyceride (TG) metabolism, is crucial for liver regeneration. During the early phase of liver regeneration, the liver temporarily accumulates a substantial amount of TG-dominated lipids. However, the specific composition of the TG profile during this phase is not yet fully understood. Here, we showed that the TG molecular composition in the liver was significantly altered during liver regeneration following carbon tetrachloride (CCl4)-induced liver injury. Lipid accumulation in livers was observed as early as 12 hours after CCl4 treatment, with transient regeneration-associated steatosis (TRAS) lasting until 24 hours. Hepatocyte proliferation began only after liver lipid levels returned to baseline at 48 hours. Furthermore, the profile of TG species changed significantly during liver regeneration. During the TRAS period, the accumulated TGs in the liver were mainly long-chain triglycerides, with most of the fatty acids constituting these triglycerides having fewer than 20 carbon atoms. In the proliferation phase, the fatty acid composition of these triglycerides shifted from long-chain to ultra-long-chain fatty acids. Our results suggest a significant TRAS-related change in the TG lipid profile of the liver during liver regeneration.

19.
J Antimicrob Chemother ; 79(4): 903-917, 2024 04 02.
Artículo en Inglés | MEDLINE | ID: mdl-38412335

RESUMEN

BACKGROUND: MDR Staphylococcus aureus infections, along with the severity of biofilm-associated infections, continue to threaten human health to a great extent. It necessitates the urgent development of novel antimicrobial and antibiofilm agents. OBJECTIVES: To reveal the mechanism and target of cinacalcet as an antibacterial and antimicrobial agent for S. aureus. METHODS: Screening of non-antibiotic drugs for antibacterial and antibiofilm properties was conducted using a small-molecule drug library. In vivo efficacy was assessed through animal models, and the antibacterial mechanism was studied using quantitative proteomics, biochemical assays, LiP-SMap, BLI detection and gene knockout techniques. RESULTS: Cinacalcet, an FDA-approved drug, demonstrated antibacterial and antibiofilm activity against S. aureus, with less observed development of bacterial resistance. Importantly, cinacalcet significantly improved survival in a pneumonia model and bacterial clearance in a biofilm infection model. Moreover, the antibacterial mechanism of cinacalcet mainly involves the destruction of membrane-targeted structures, alteration of energy metabolism, and production of reactive oxygen species (ROS). Cinacalcet was found to target IcaR, inhibiting biofilm formation through the negative regulation of IcaADBC. CONCLUSIONS: The findings suggest that cinacalcet has potential for repurposing as a therapeutic agent for MDR S. aureus infections and associated biofilms, warranting further investigation.


Asunto(s)
Antiinfecciosos , Staphylococcus aureus Resistente a Meticilina , Infecciones Estafilocócicas , Animales , Humanos , Staphylococcus aureus , Cinacalcet/farmacología , Cinacalcet/uso terapéutico , Complejo Hierro-Dextran/uso terapéutico , Reposicionamiento de Medicamentos , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Antiinfecciosos/uso terapéutico , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/microbiología , Membrana Celular , Biopelículas , Pruebas de Sensibilidad Microbiana
20.
J Antimicrob Chemother ; 79(8): 1951-1961, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38863365

RESUMEN

OBJECTIVES: Pseudomonas aeruginosa and Acinetobacter baumannii are ranked as top-priority organisms by WHO. Antimicrobial peptides (AMPs) are promising antimicrobial agents that are highly effective against serious bacterial infections. METHODS: In our previous study, a series of α-helical AMPs were screened using a novel multiple-descriptor strategy. The current research suggested that S24 exhibited strong antimicrobial activity against major pathogenic bacteria, and displayed minimal haemolysis, good serum stability and maintained salt resistance. RESULTS: We found that S24 exerted an antimicrobial effect by destroying outer membrane permeability and producing a strong binding effect on bacterial genomic DNA that inhibits genomic DNA migration. Furthermore, S24 exerted a strong ability to promote healing in wound infected by P. aeruginosa, A. baumannii and mixed strains in a mouse model. CONCLUSIONS: Overall, S24 showed good stability under physiological conditions and excellent antimicrobial activity, suggesting it may be a potential candidate for the development of serious bacterial infection treatment.


Asunto(s)
Infecciones por Acinetobacter , Acinetobacter baumannii , Antibacterianos , Pruebas de Sensibilidad Microbiana , Infecciones por Pseudomonas , Pseudomonas aeruginosa , Infección de Heridas , Acinetobacter baumannii/efectos de los fármacos , Pseudomonas aeruginosa/efectos de los fármacos , Animales , Infección de Heridas/tratamiento farmacológico , Infección de Heridas/microbiología , Ratones , Infecciones por Acinetobacter/tratamiento farmacológico , Infecciones por Acinetobacter/microbiología , Infecciones por Pseudomonas/tratamiento farmacológico , Infecciones por Pseudomonas/microbiología , Antibacterianos/farmacología , Péptidos Antimicrobianos/farmacología , Péptidos Antimicrobianos/química , Modelos Animales de Enfermedad , Permeabilidad de la Membrana Celular/efectos de los fármacos , Humanos , ADN Bacteriano/genética
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA