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1.
Cell ; 187(5): 1296-1311.e26, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38428397

RESUMEN

Most membrane proteins are modified by covalent addition of complex sugars through N- and O-glycosylation. Unlike proteins, glycans do not typically adopt specific secondary structures and remain very mobile, shielding potentially large fractions of protein surface. High glycan conformational freedom hinders complete structural elucidation of glycoproteins. Computer simulations may be used to model glycosylated proteins but require hundreds of thousands of computing hours on supercomputers, thus limiting routine use. Here, we describe GlycoSHIELD, a reductionist method that can be implemented on personal computers to graft realistic ensembles of glycan conformers onto static protein structures in minutes. Using molecular dynamics simulation, small-angle X-ray scattering, cryoelectron microscopy, and mass spectrometry, we show that this open-access toolkit provides enhanced models of glycoprotein structures. Focusing on N-cadherin, human coronavirus spike proteins, and gamma-aminobutyric acid receptors, we show that GlycoSHIELD can shed light on the impact of glycans on the conformation and activity of complex glycoproteins.


Asunto(s)
Glicoproteínas , Simulación de Dinámica Molecular , Humanos , Microscopía por Crioelectrón , Glicoproteínas/química , Glicosilación , Polisacáridos/química
2.
Cell ; 185(14): 2478-2494.e28, 2022 07 07.
Artículo en Inglés | MEDLINE | ID: mdl-35662413

RESUMEN

Glucagon-like peptide-1 (GLP-1) is a signal peptide released from enteroendocrine cells of the lower intestine. GLP-1 exerts anorectic and antimotility actions that protect the body against nutrient malabsorption. However, little is known about how intestinal GLP-1 affects distant organs despite rapid enzymatic inactivation. We show that intestinal GLP-1 inhibits gastric emptying and eating via intestinofugal neurons, a subclass of myenteric neurons that project to abdominal sympathetic ganglia. Remarkably, cell-specific ablation of intestinofugal neurons eliminated intestinal GLP-1 effects, and their chemical activation functioned as a GLP-1 mimetic. GLP-1 sensing by intestinofugal neurons then engaged a sympatho-gastro-spinal-reticular-hypothalamic pathway that links abnormal stomach distension to craniofacial programs for food rejection. Within this pathway, cell-specific activation of discrete neuronal populations caused systemic GLP-1-like effects. These molecularly identified, delimited enteric circuits may be targeted to ameliorate the abdominal bloating and loss of appetite typical of gastric motility disorders.


Asunto(s)
Apetito , Péptido 1 Similar al Glucagón/metabolismo , Íleon , Neuronas , Estómago , Abdomen , Animales , Comunicación Celular , Receptor del Péptido 1 Similar al Glucagón/metabolismo , Íleon/inervación , Íleon/metabolismo , Masculino , Ratones , Neuronas/metabolismo , Óxido Nítrico/metabolismo , Transducción de Señal , Estómago/inervación , Estómago/metabolismo
3.
Cell ; 173(7): 1636-1649.e16, 2018 06 14.
Artículo en Inglés | MEDLINE | ID: mdl-29754813

RESUMEN

Hydrogen gas-evolving membrane-bound hydrogenase (MBH) and quinone-reducing complex I are homologous respiratory complexes with a common ancestor, but a structural basis for their evolutionary relationship is lacking. Here, we report the cryo-EM structure of a 14-subunit MBH from the hyperthermophile Pyrococcus furiosus. MBH contains a membrane-anchored hydrogenase module that is highly similar structurally to the quinone-binding Q-module of complex I while its membrane-embedded ion-translocation module can be divided into a H+- and a Na+-translocating unit. The H+-translocating unit is rotated 180° in-membrane with respect to its counterpart in complex I, leading to distinctive architectures for the two respiratory systems despite their largely conserved proton-pumping mechanisms. The Na+-translocating unit, absent in complex I, resembles that found in the Mrp H+/Na+ antiporter and enables hydrogen gas evolution by MBH to establish a Na+ gradient for ATP synthesis near 100°C. MBH also provides insights into Mrp structure and evolution of MBH-based respiratory enzymes.


Asunto(s)
Proteínas Arqueales/metabolismo , Hidrogenasas/metabolismo , Pyrococcus furiosus/metabolismo , Secuencia de Aminoácidos , Proteínas Arqueales/química , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Sitios de Unión , Membrana Celular/química , Membrana Celular/metabolismo , Microscopía por Crioelectrón , Complejo I de Transporte de Electrón/química , Complejo I de Transporte de Electrón/metabolismo , Evolución Molecular , Hidrógeno/metabolismo , Hidrogenasas/química , Hidrogenasas/genética , Mutagénesis , Estructura Cuaternaria de Proteína , Subunidades de Proteína/química , Subunidades de Proteína/genética , Subunidades de Proteína/metabolismo , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/química , Proteínas Recombinantes/aislamiento & purificación , Alineación de Secuencia , Sodio/química , Sodio/metabolismo , Intercambiadores de Sodio-Hidrógeno/química , Intercambiadores de Sodio-Hidrógeno/metabolismo
4.
Nature ; 625(7993): 157-165, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38093016

RESUMEN

Evidence is accumulating that perturbed postnatal development of the gut microbiome contributes to childhood malnutrition1-4. Here we analyse biospecimens from a randomized, controlled trial of a microbiome-directed complementary food (MDCF-2) that produced superior rates of weight gain compared with a calorically more dense conventional ready-to-use supplementary food in 12-18-month-old Bangladeshi children with moderate acute malnutrition4. We reconstructed 1,000 bacterial genomes (metagenome-assembled genomes (MAGs)) from the faecal microbiomes of trial participants, identified 75 MAGs of which the abundances were positively associated with ponderal growth (change in weight-for-length Z score (WLZ)), characterized changes in MAG gene expression as a function of treatment type and WLZ response, and quantified carbohydrate structures in MDCF-2 and faeces. The results reveal that two Prevotella copri MAGs that are positively associated with WLZ are the principal contributors to MDCF-2-induced expression of metabolic pathways involved in utilizing the component glycans of MDCF-2. The predicted specificities of carbohydrate-active enzymes expressed by their polysaccharide-utilization loci are correlated with (1) the in vitro growth of Bangladeshi P. copri strains, possessing varying degrees of polysaccharide-utilization loci and genomic conservation with these MAGs, in defined medium containing different purified glycans representative of those in MDCF-2, and (2) the levels of faecal carbohydrate structures in the trial participants. These associations suggest that identifying bioactive glycan structures in MDCFs metabolized by growth-associated bacterial taxa will help to guide recommendations about their use in children with acute malnutrition and enable the development of additional formulations.


Asunto(s)
Alimentos , Microbioma Gastrointestinal , Desnutrición , Polisacáridos , Humanos , Lactante , Bacterias/genética , Bangladesh , Peso Corporal/genética , Heces/microbiología , Microbioma Gastrointestinal/fisiología , Genoma Bacteriano/genética , Desnutrición/microbiología , Metagenoma/genética , Polisacáridos/metabolismo , Aumento de Peso
5.
Proc Natl Acad Sci U S A ; 121(2): e2315898120, 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38165930

RESUMEN

Protection against endothelial damage is recognized as a frontline approach to preventing the progression of cytokine release syndrome (CRS). Accumulating evidence has demonstrated that interleukin-6 (IL-6) promotes vascular endothelial damage during CRS, although the molecular mechanisms remain to be fully elucidated. Targeting IL-6 receptor signaling delays CRS progression; however, current options are limited by persistent inhibition of the immune system. Here, we show that endothelial IL-6 trans-signaling promoted vascular damage and inflammatory responses via hypoxia-inducible factor-1α (HIF1α)-induced glycolysis. Using pharmacological inhibitors targeting HIF1α activity or mice with the genetic ablation of gp130 in the endothelium, we found that inhibition of IL-6R (IL-6 receptor)-HIF1α signaling in endothelial cells protected against vascular injury caused by septic damage and provided survival benefit in a mouse model of sepsis. In addition, we developed a short half-life anti-IL-6R antibody (silent anti-IL-6R antibody) and found that it was highly effective at augmenting survival for sepsis and severe burn by strengthening the endothelial glycocalyx and reducing cytokine storm, and vascular leakage. Together, our data advance the role of endothelial IL-6 trans-signaling in the progression of CRS and indicate a potential therapeutic approach for burns and sepsis.


Asunto(s)
Receptor gp130 de Citocinas , Subunidad alfa del Factor 1 Inducible por Hipoxia , Interleucina-6 , Receptores de Interleucina-6 , Sepsis , Animales , Ratones , Receptor gp130 de Citocinas/genética , Síndrome de Liberación de Citoquinas , Células Endoteliales , Receptores de Interleucina-6/genética , Sepsis/tratamiento farmacológico , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética
6.
Proc Natl Acad Sci U S A ; 121(19): e2321836121, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38687788

RESUMEN

Interleukin 22 (IL-22) promotes intestinal barrier integrity, stimulating epithelial cells to enact defense mechanisms against enteric infections, including the production of antimicrobial peptides. IL-22 binding protein (IL-22BP) is a soluble decoy encoded by the Il22ra2 gene that decreases IL-22 bioavailability, attenuating IL-22 signaling. The impact of IL-22BP on gut microbiota composition and functioning is poorly understood. We found that Il22ra2-/- mice are better protected against Clostridioides difficile and Citrobacter rodentium infections. This protection relied on IL-22-induced antimicrobial mechanisms before the infection occurred, rather than during the infection itself. Indeed, the gut microbiota of Il22ra2-/- mice mitigated infection of wild-type (WT) mice when transferred via cohousing or by cecal microbiota transplantation. Indicator species analysis of WT and Il22ra2-/- mice with and without cohousing disclosed that IL22BP deficiency yields a gut bacterial composition distinct from that of WT mice. Manipulation of dietary fiber content, measurements of intestinal short-chain fatty acids and oral treatment with acetate disclosed that resistance to C. difficile infection is related to increased production of acetate by Il22ra2-/--associated microbiota. Together, these findings suggest that IL-22BP represents a potential therapeutic target for those at risk for or with already manifest infection with this and perhaps other enteropathogens.


Asunto(s)
Citrobacter rodentium , Clostridioides difficile , Infecciones por Enterobacteriaceae , Microbioma Gastrointestinal , Interleucina-22 , Ratones Noqueados , Animales , Ratones , Infecciones por Enterobacteriaceae/inmunología , Infecciones por Enterobacteriaceae/microbiología , Infecciones por Enterobacteriaceae/prevención & control , Receptores de Interleucina/metabolismo , Receptores de Interleucina/genética , Interleucinas/metabolismo , Ratones Endogámicos C57BL , Infecciones por Clostridium/inmunología , Infecciones por Clostridium/microbiología , Infecciones por Clostridium/prevención & control
7.
Development ; 150(4)2023 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-36786332

RESUMEN

Precise genome manipulation in specific cell types and subtypes in vivo is crucial for neurobiological research because of the cellular heterogeneity of the brain. Site-specific recombinase systems in the mouse, such as Cre-loxP, improve cell type-specific genome manipulation; however, undesirable expression of cell type-specific Cre can occur. This could be due to transient expression during early development, natural expression in more than one cell type, kinetics of recombinases, sensitivity of the Cre reporter, and disruption in cis-regulatory elements by transgene insertion. Moreover, cell subtypes cannot be distinguished in cell type-specific Cre mice. To address these issues, we applied an intersectional genetic approach in mouse using triple recombination systems (Cre-loxP, Flp-FRT and Dre-rox). As a proof of principle, we labelled heterogeneous cell subtypes and deleted target genes within given cell subtypes by labelling neuropeptide Y (NPY)-, calretinin (calbindin 2) (CR)- and cholecystokinin (CCK)-expressing GABAergic neurons in the brain followed by deletion of RNA-binding Fox-1 homolog 3 (Rbfox3) in our engineered mice. Together, our study applies an intersectional genetic approach in vivo to generate engineered mice serving dual purposes of simultaneous cell subtype-specific labelling and gene knockout.


Asunto(s)
Integrasas , Recombinasas , Ratones , Animales , Técnicas de Inactivación de Genes , Integrasas/metabolismo , Recombinasas/genética , Recombinasas/metabolismo , Transgenes , Encéfalo/metabolismo , Ratones Transgénicos
8.
Development ; 149(22)2022 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-36305473

RESUMEN

The polarity of mouse hair follicles is controlled by the Frizzled (Fzd) receptors and other membrane planar cell polarity (PCP) proteins. Whether Wnt proteins can act as PCP ligands in the skin remains unknown. Here, we show that overexpression of Wnt5a in the posterior part of mouse embryos causes a local disruption of hair follicle orientation. The misoriented hair follicle phenotype in Wnt5a overexpressing mice can be rescued by a heterozygous loss of Fzd6, suggesting Wnt5a is likely to signal through Fzd6. Although the membrane distribution of PCP proteins seems unaffected by Wnt5a overexpression, transcriptional profiling analyses identify a set of genes as potential targets of the skin polarization program controlled by Wnt5a/Fzd6 signaling. Surprisingly, deletion of Wnt5a globally or in the posterior part of the mouse embryos does not affect hair follicle orientation. We show that many other Wnts are highly expressed in the developing skin. They can activate the Fzd6 signaling pathway in vitro and may act together with Wnt5a to regulate the Fzd6-mediated skin polarization. Our experiments demonstrate for the first time that Wnt5a can function as an orienting cue for mouse skin PCP.


Asunto(s)
Folículo Piloso , Proteínas Wnt , Animales , Ratones , Polaridad Celular/genética , Folículo Piloso/metabolismo , Transducción de Señal/genética , Piel/metabolismo , Proteínas Wnt/genética , Proteínas Wnt/metabolismo , Proteína Wnt-5a/genética , Proteína Wnt-5a/metabolismo
9.
Cereb Cortex ; 34(4)2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38602740

RESUMEN

This study aimed to investigate the moderating role of aerobic fitness on the effect of acute exercise on improving executive function from both behavioral and cerebral aspects. Thirty-four young individuals with motor skills were divided into high- and low-fitness groups based on their maximal oxygen uptake. Both groups completed 30 min of moderate-intensity aerobic exercise on a power bike. Executive function tests (Flanker, N-back, More-odd-shifting) were performed before and after exercise and functional near-infrared spectroscopy was used to monitor prefrontal cerebral blood flow changes during the tasks. The results indicated significant differences between the two groups regarding executive function. Participants with lower aerobic fitness performed better than their higher fitness counterparts in inhibitory control and working memory, but not in cognitive flexibility. This finding suggests that the aerobic fitness may moderate the extent of cognitive benefits gained from acute aerobic exercise. Furthermore, the neuroimaging data indicated negative activation in the frontopolar area and dorsolateral prefrontal cortex in response to three complex tasks. These findings underscore the importance of considering individual aerobic fitness when assessing the cognitive benefits of exercise and could have significant implications for tailoring fitness programs to enhance cognitive performance.


Asunto(s)
Función Ejecutiva , Ejercicio Físico , Humanos , Memoria a Corto Plazo , Circulación Cerebrovascular , Corteza Prefontal Dorsolateral
10.
Nucleic Acids Res ; 51(21): 11717-11731, 2023 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-37843130

RESUMEN

Fork reversal is a conserved mechanism to prevent stalled replication forks from collapsing. Formation and protection of reversed forks are two crucial steps in ensuring fork integrity and stability. Five RAD51 paralogs, namely, RAD51B, RAD51C, RAD51D, XRCC2 and XRCC3, which share sequence and structural similarity to the recombinase RAD51, play poorly defined mechanistic roles in these processes. Here, using purified BCDX2 (RAD51BCD-XRCC2) and CX3 (RAD51C-XRCC3) complexes and in vitro reconstituted biochemical systems, we mechanistically dissect their functions in forming and protecting reversed forks. We show that both RAD51 paralog complexes lack fork reversal activities. Whereas CX3 exhibits modest fork protection activity, BCDX2 significantly synergizes with RAD51 to protect DNA against attack by the nucleases MRE11 and EXO1. DNA protection is contingent upon the ability of RAD51 to form a functional nucleoprotein filament on DNA. Collectively, our results provide evidence for a hitherto unknown function of RAD51 paralogs in synergizing with RAD51 nucleoprotein filament to prevent degradation of stressed replication forks.


Asunto(s)
Replicación del ADN , Recombinasa Rad51 , Línea Celular , Cromosomas/metabolismo , ADN/genética , ADN/metabolismo , Nucleoproteínas/genética , Recombinasa Rad51/genética , Recombinasa Rad51/metabolismo , Humanos
11.
J Biol Chem ; 299(1): 102728, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36410433

RESUMEN

Haploinsufficiency in retinoic acid induced 1 (RAI1) causes Smith-Magenis syndrome (SMS), a severe neurodevelopmental disorder characterized by neurocognitive deficits and obesity. Currently, curative treatments for SMS do not exist. Here, we take a recombinant adeno-associated virus (rAAV)-clustered regularly interspaced short palindromic repeats activation (CRISPRa) approach to increase expression of the remaining intact Rai1 allele. Building upon our previous work that found the paraventricular nucleus of hypothalamus plays a central role in SMS pathogenesis, we performed paraventricular nucleus of hypothalamus-specific rAAV-CRISPRa therapy by increasing endogenous Rai1 expression in SMS (Rai1±) mice. We found that rAAV-CRISPRa therapy rescues excessive repetitive behavior, delays the onset of obesity, and partially reduces hyperphagia in SMS mice. Our work provides evidence that rAAV-CRISPRa therapy during early adolescence can boost the expression of healthy Rai1 allele and modify disease progression in a mouse model of Smith-Magenis syndrome.


Asunto(s)
Síndrome de Smith-Magenis , Ratones , Animales , Síndrome de Smith-Magenis/genética , Síndrome de Smith-Magenis/terapia , Síndrome de Smith-Magenis/metabolismo , Transactivadores/genética , Transactivadores/metabolismo , Dependovirus/genética , Dependovirus/metabolismo , Haploinsuficiencia , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas , Obesidad/genética
12.
BMC Plant Biol ; 24(1): 155, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38424508

RESUMEN

BACKGROUND: Powdery mildew (PM) is one of the important soybean diseases, and host resistance could practically contribute to soybean PM management. To date, only the Rmd locus on chromosome (Chr) 16 was identified through traditional QTL mapping and GWAS, and it remains unclear if the bulk segregant RNA-Seq (BSR-Seq) methodology is feasible to explore additional PM resistance that might exist in other varieties. RESULTS: BSR-Seq was applied to contrast genotypes and gene expressions between the resistant bulk (R bulk) and the susceptible bulk (S bulk), as well as the parents. The ∆(SNP-index) and G' value identified several QTL and significant SNPs/Indels on Chr06, Chr15, and Chr16. Differentially expressed genes (DEGs) located within these QTL were identified using HISAT2 and Kallisto, and allele-specific primers (AS-primers) were designed to validate the accuracy of phenotypic prediction. While the AS-primers on Chr06 or Chr15 cannot distinguish the resistant and susceptible phenotypes, AS-primers on Chr16 exhibited 82% accuracy prediction with an additive effect, similar to the SSR marker Satt431. CONCLUSIONS: Evaluation of additional AS-primers in the linkage disequilibrium (LD) block on Chr16 further confirmed the resistant locus, derived from the resistant parental variety 'Kaohsiung 11' ('KS11'), not only overlaps with the Rmd locus with unique up-regulated LRR genes (Glyma.16G213700 and Glyma.16G215100), but also harbors a down-regulated MLO gene (Glyma.16G145600). Accordingly, this study exemplified the feasibility of BSR-Seq in studying biotrophic disease resistance in soybean, and showed the genetic makeup of soybean variety 'KS11' comprising the Rmd locus and one MLO gene.


Asunto(s)
Resistencia a la Enfermedad , Glycine max , Glycine max/genética , RNA-Seq , Alelos , Mapeo Cromosómico/métodos , Fenotipo , Resistencia a la Enfermedad/genética , Erysiphe , Enfermedades de las Plantas/genética
13.
Small ; 20(16): e2307523, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38018331

RESUMEN

Sustained-release drug delivery formulations are preferable for treating various diseases as they enhance and prolong efficacy, minimize adverse effects, and avoid frequent dosing. However, these formulations are associated with poor patient compliance, require trained personnel for administration, and involve harsh manufacturing conditions that compromise drug stability. Here, a self-healing biodegradable porous microneedle (PMN) patch is reported for sustained drug delivery. The PMN patch is fabricated by a cryogenic micromoulding followed by phase separation, leading to formation of interconnected pores on the surface and internals of MNs. The pores with self-healing feature enable the PMNs to load hydrophilic drugs with different molecular weights in a mild and efficient manner. The healed PMNs can easily penetrate into the skin under press and detach from the supporting substrate under shear, thereby acting as implantable drug reservoirs for achieving sustained release of drugs for at least 40 days. One-time administration of desired therapeutics using the sustained-release healed PMNs resulted in stronger and longer-lasting efficacy in mitigating psoriasis and eliciting immunity compared to conventional methods with multiple administrations. The self-healing PMN patch for self-administrated and long-acting drug delivery can eventually improve medication adherence in prophylactic and therapeutic protocols that typically require frequent dosages.


Asunto(s)
Separación de Fases , Piel , Humanos , Preparaciones de Acción Retardada/farmacología , Administración Cutánea , Porosidad , Sistemas de Liberación de Medicamentos/métodos , Agujas
14.
Small ; 20(8): e2304693, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37822153

RESUMEN

Tumor penetration of nanoparticles is crucial in nanomedicine, but the mechanisms of tumor penetration are poorly understood. This work presents a multidimensional, quantitative approach to investigate the tissue penetration behavior of nanoparticles, with focuses on the particle size effect on penetration pathways, in an MDA-MB-231 tumor spheroid model using a combination of spectrometry, microscopy, and synchrotron beamline techniques. Quasi-spherical gold nanoparticles of different sizes are synthesized and incubated with 2D and 3D MDA-MB-231 cells and spheroids with or without an energy-dependent cell uptake inhibitor. The distribution and penetration pathways of nanoparticles in spheroids are visualized and quantified by inductively coupled plasma mass spectrometry, two-photon microscopy, and synchrotron X-ray fluorescence microscopy. The results reveal that 15 nm nanoparticles penetrate spheroids mainly through an energy-independent transcellular pathway, while 60 nm nanoparticles penetrate primarily through an energy-dependent transcellular pathway. Meanwhile, 22 nm nanoparticles penetrate through both transcellular and paracellular pathways and they demonstrate the greatest penetration ability in comparison to other two sizes. The multidimensional analytical methodology developed through this work offers a generalizable approach to quantitatively study the tissue penetration of nanoparticles, and the results provide important insights into the designs of nanoparticles with high accumulation at a target site.


Asunto(s)
Nanopartículas del Metal , Nanopartículas , Neoplasias , Humanos , Oro/química , Esferoides Celulares , Nanopartículas/química , Microscopía
15.
Plant Cell Environ ; 47(6): 2011-2026, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38392921

RESUMEN

Crispr/CAS9-enabled homologous recombination to insert a tag in frame with an endogenous gene can circumvent difficulties such as context-dependent promoter activity that complicate analysis of gene expression and protein accumulation patterns. However, there have been few reports examining whether such gene targeting/gene tagging (GT) can alter expression of the target gene. The enzyme encoded by Δ1-pyrroline-5-carboxylate synthetase 1 (P5CS1) is key for stress-induced proline synthesis and drought resistance, yet its expression pattern and protein localisation have been difficult to assay. We used GT to insert YFP in frame with the 5' or 3' ends of the endogenous P5CS1 and At14a-Like 1 (AFL1) coding regions. Insertion at the 3' end of either gene generated homozygous lines with expression of the gene-YFP fusion indistinguishable from the wild type allele. However, for P5CS1 this occurred only after selfing and advancement to the T5 generation allowed initial homozygous lethality of the insertion to be overcome. Once this was done, the GT-generated P5CS1-YFP plants revealed new information about P5CS1 localisation and tissue-specific expression. In contrast, insertion of YFP at the 5' end of either gene blocked expression. The results demonstrate that GT can be useful for functional analyses of genes that are problematic to properly express by other means but also show that, in some cases, GT can disrupt expression of the target gene.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Arabidopsis/fisiología , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Plantas Modificadas Genéticamente , Regulación de la Expresión Génica de las Plantas , Estrés Fisiológico/genética , Mutagénesis Insercional/genética , Proteínas Luminiscentes/genética , Proteínas Luminiscentes/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo
16.
Respir Res ; 25(1): 65, 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38317222

RESUMEN

BACKGROUND: Endobronchial ultrasound (EBUS) and cone-beam computed tomography-derived augmented fluoroscopy (CBCT-AF) are utilized for the diagnosis of peripheral pulmonary lesions (PPLs). Combining them with transbronchial cryobiopsy (TBC) can provide sufficient tissue for genetic analysis. However, cryoprobes of different sizes have varying degrees of flexibility, which can affect their ability to access the target bronchus and potentially impact the accuracy. The aim of this study was to compare the diagnostic efficacy of cryoprobes of varying sizes in CBCT-AF and EBUS for the diagnosis of PPLs. METHODS: Patients who underwent endobronchial ultrasound-guided transbronchial biopsy (EBUS-TBB) and TBC combined with CBCT-AF for PPLs diagnosis between January 2021 and May 2022 were included. Propensity score matching and competing-risks regression were utilized for data analysis. Primary outcome was the diagnostic accuracy of TBC. RESULTS: A total of 284 patients underwent TBC, with 172 using a 1.7-mm cryoprobe (1.7 group) and 112 using a 1.1-mm cryoprobe (1.1 group). Finally, we included 99 paired patients following propensity score matching. The diagnostic accuracy of TBC was higher in the 1.1 group (80.8% vs. 69.7%, P = 0.050), with a similar rate of complications. Subgroup analysis also revealed that the 1.1 group had better accuracy when PPLs were located in the upper lobe (85.2% vs. 66.1%, P = 0.020), when PPLs were smaller than 20 mm (78.8% vs. 48.8%, P = 0.008), and when intra-procedural CBCT was needed to be used (79.5% vs. 42.3%, P = 0.001). TBC obtained larger specimens than TBB in both groups. There is still a trend of larger sample size obtained in the 1.7 group, but there is no statistically different between our two study groups (40.8 mm2 vs. 22.0 mm2, P = 0.283). CONCLUSIONS: The combination of TBC with CBCT-AF and EBUS is effective in diagnosing PPLs, and a thin cryoprobe is preferred when the PPLs located in difficult areas.


Asunto(s)
Enfermedades Pulmonares , Neoplasias Pulmonares , Humanos , Enfermedades Pulmonares/diagnóstico , Broncoscopía , Biopsia Guiada por Imagen , Neoplasias Pulmonares/patología , Biopsia , Tomografía Computarizada de Haz Cónico , Fluoroscopía , Estudios Retrospectivos
17.
Diabetes Metab Res Rev ; 40(2): e3775, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38340046

RESUMEN

AIMS: The effectiveness of sodium-glucose co-transporter-2 inhibitors (SGLT2i) on incident dementia in patients with diabetes and atrial fibrillation (AF) remains unknown. This study aimed to investigate the association between SGLT2i and the risk of incident dementia in diabetic patients with AF, and to explore the interactions with oral anticoagulants or dipeptidyl peptidase-4 inhibitors (DPP4i). MATERIALS AND METHODS: We conducted a cohort study using Taiwan's National Health Insurance Research Database. Patients with diabetes and AFwithout a prior history of established cardiovascular diseases, were identified. Using propensity score matching, 810 patients receiving SGLT2i were matched with 1620 patients not receiving SGLT2i. The primary outcome was incident dementia, and secondary outcomes included composite cardiovascular events and mortality. RESULTS: After up to 5 years of follow-up, SGLT2i use was associated with a significantly lower risk of incident dementia (hazard: 0.71, 95% confidence interval: 0.51-0.98), particularly vascular dementia (HR: 0.44, 95% CI: 0.24-0.82). SGLT2i was related to reduced risks of AF-related hospitalisation (HR: 0.72, 95% CI: 0.56-0.93), stroke (HR: 0.75, 95% CI: 0.60-0.94), and all-cause death (HR: 0.33, 95% CI: 0.24-0.44). The protective effects were consistent irrespective of the concurrent use of non-vitamin K antagonist oral anticoagulants (NOACs) or DPP4i. CONCLUSIONS: In diabetic patients with AF, SGLT2i was associated with reduced risks of incident dementia, AF-related hospitalisation, stroke, and all-cause death. The protective effects were independent of either concurrent use of NOACs or DPP4i.


Asunto(s)
Fibrilación Atrial , Demencia , Diabetes Mellitus Tipo 2 , Diabetes Mellitus , Inhibidores de la Dipeptidil-Peptidasa IV , Inhibidores del Cotransportador de Sodio-Glucosa 2 , Accidente Cerebrovascular , Simportadores , Humanos , Fibrilación Atrial/complicaciones , Fibrilación Atrial/tratamiento farmacológico , Fibrilación Atrial/epidemiología , Administración Oral , Estudios de Cohortes , Anticoagulantes , Inhibidores de la Dipeptidil-Peptidasa IV/uso terapéutico , Inhibidores del Cotransportador de Sodio-Glucosa 2/uso terapéutico , Demencia/epidemiología , Demencia/prevención & control , Glucosa , Sodio , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hipoglucemiantes , Estudios Retrospectivos
18.
Nat Chem Biol ; 18(11): 1196-1203, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35982227

RESUMEN

Adhesion G protein-coupled receptors are elusive in terms of their structural information and ligands. Here, we solved the cryogenic-electron microscopy (cryo-EM) structure of apo-ADGRG2, an essential membrane receptor for maintaining male fertility, in complex with a Gs trimer. Whereas the formations of two kinks were determinants of the active state, identification of a potential ligand-binding pocket in ADGRG2 facilitated the screening and identification of dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulfate and deoxycorticosterone as potential ligands of ADGRG2. The cryo-EM structures of DHEA-ADGRG2-Gs provided interaction details for DHEA within the seven transmembrane domains of ADGRG2. Collectively, our data provide a structural basis for the activation and signaling of ADGRG2, as well as characterization of steroid hormones as ADGRG2 ligands, which might be used as useful tools for further functional studies of the orphan ADGRG2.


Asunto(s)
Receptores Acoplados a Proteínas G , Transducción de Señal , Humanos , Masculino , Microscopía por Crioelectrón , Sulfato de Deshidroepiandrosterona , Desoxicorticosterona , Ligandos , Receptores Acoplados a Proteínas G/química
19.
Environ Sci Technol ; 58(23): 9980-9990, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38819024

RESUMEN

Exposure to fine particulate matter (PM2.5) during pregnancy has been inversely associated with neonatal neurological development. However, the associations of exposure to specific PM2.5 constituents with neonatal neurological development remain unclear. We investigated these associations and examined the mediating role of meconium metabolites in a Chinese birth cohort consisting of 294 mother-infant pairs. Our results revealed that exposure to PM2.5 and its specific constituents (i.e., organic matter, black carbon, sulfate, nitrate, and ammonium) in the second trimester, but not in the first or third trimester, was inversely associated with the total neonatal behavioral neurological assessment (NBNA) scores. The PM2.5 constituent mixture in the second trimester was also inversely associated with NBNA scores, and sulfate was identified as the largest contributor. Furthermore, meconium metabolome analysis identified four metabolites, namely, threonine, lysine, leucine, and saccharopine, that were associated with both PM2.5 constituents and NBNA scores. Threonine was identified as an important mediator, accounting for a considerable proportion (14.53-15.33%) of the observed inverse associations. Our findings suggest that maternal exposure to PM2.5 and specific constituents may adversely affect neonatal behavioral development, in which meconium metabolites may play a mediating role.


Asunto(s)
Exposición Materna , Meconio , Material Particulado , Humanos , Femenino , Meconio/química , Embarazo , Estudios de Cohortes , Recién Nacido , Adulto , Contaminantes Atmosféricos
20.
Bioorg Med Chem ; 109: 117792, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38897139

RESUMEN

Cancer has been a leading cause of death over the last few decades in western countries as well as in Taiwan. However, traditional therapies are limited by the adverse effects of chemotherapy and radiotherapy, and tumor recurrence may occur. Therefore, it is critical to develop novel therapeutic drugs. In the field of HDAC inhibitor development, apart from the hydroxamic acid moiety, 2-aminobenzamide also functions as a zinc-binding domain, which is shown in well-known HDAC inhibitors such as Entinostat and Chidamide. With recent successful experiences in synthesizing 1-(phenylsulfonyl)indole-based compounds, in this study, we further combined two features of the above chemical compounds and generated indolyl benzamides. Compounds were screened in different cancer cell lines, and enzyme activity was examined to demonstrate their potential for anti-HDAC activity. Various biological functional assays evidenced that two of these compounds could suppress cancer growth and migration capacity, through regulating epithelial-mesenchymal transition (EMT), cell cycle, and apoptosis mechanisms. Data from 3D cancer cells and the in vivo zebrafish model suggested the potential of these compounds in cancer therapy in the future.


Asunto(s)
Antineoplásicos , Apoptosis , Ciclo Celular , Proliferación Celular , Ensayos de Selección de Medicamentos Antitumorales , Transición Epitelial-Mesenquimal , Inhibidores de Histona Desacetilasas , Pez Cebra , Inhibidores de Histona Desacetilasas/farmacología , Inhibidores de Histona Desacetilasas/química , Inhibidores de Histona Desacetilasas/síntesis química , Humanos , Apoptosis/efectos de los fármacos , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/síntesis química , Transición Epitelial-Mesenquimal/efectos de los fármacos , Animales , Ciclo Celular/efectos de los fármacos , Relación Estructura-Actividad , Proliferación Celular/efectos de los fármacos , Estructura Molecular , Relación Dosis-Respuesta a Droga , Línea Celular Tumoral , Histona Desacetilasas/metabolismo
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