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1.
Cell ; 187(5): 1296-1311.e26, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38428397

RESUMO

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.


Assuntos
Glicoproteínas , Simulação de Dinâmica Molecular , Humanos , Microscopia Crioeletrônica , Glicoproteínas/química , Glicosilação , Polissacarídeos/química
2.
Cell ; 185(14): 2478-2494.e28, 2022 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-35662413

RESUMO

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.


Assuntos
Apetite , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Íleo , Neurônios , Estômago , Abdome , Animais , Comunicação Celular , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Íleo/inervação , Íleo/metabolismo , Masculino , Camundongos , Neurônios/metabolismo , Óxido Nítrico/metabolismo , Transdução de Sinais , Estômago/inervação , Estômago/metabolismo
3.
Cell ; 173(7): 1636-1649.e16, 2018 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-29754813

RESUMO

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.


Assuntos
Proteínas Arqueais/metabolismo , Hidrogenase/metabolismo , Pyrococcus furiosus/metabolismo , Sequência de Aminoácidos , Proteínas Arqueais/química , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Sítios de Ligação , Membrana Celular/química , Membrana Celular/metabolismo , Microscopia Crioeletrônica , Complexo I de Transporte de Elétrons/química , Complexo I de Transporte de Elétrons/metabolismo , Evolução Molecular , Hidrogênio/metabolismo , Hidrogenase/química , Hidrogenase/genética , Mutagênese , Estrutura Quaternária de Proteína , Subunidades Proteicas/química , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Alinhamento de Sequência , Sódio/química , Sódio/metabolismo , Trocadores de Sódio-Hidrogênio/química , Trocadores de Sódio-Hidrogênio/metabolismo
4.
Nature ; 625(7993): 157-165, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38093016

RESUMO

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.


Assuntos
Alimentos , Microbioma Gastrointestinal , Desnutrição , Polissacarídeos , Humanos , Lactente , Bactérias/genética , Bangladesh , Peso Corporal/genética , Fezes/microbiologia , Microbioma Gastrointestinal/fisiologia , Genoma Bacteriano/genética , Desnutrição/microbiologia , Metagenoma/genética , Polissacarídeos/metabolismo , Aumento de Peso
5.
Proc Natl Acad Sci U S A ; 121(2): e2315898120, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38165930

RESUMO

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.


Assuntos
Receptor gp130 de Citocina , Subunidade alfa do Fator 1 Induzível por Hipóxia , Interleucina-6 , Receptores de Interleucina-6 , Sepse , Animais , Camundongos , Receptor gp130 de Citocina/genética , Síndrome da Liberação de Citocina , Células Endoteliais , Receptores de Interleucina-6/genética , Sepse/tratamento farmacológico , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética
6.
Proc Natl Acad Sci U S A ; 121(19): e2321836121, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38687788

RESUMO

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.


Assuntos
Citrobacter rodentium , Clostridioides difficile , Infecções por Enterobacteriaceae , Microbioma Gastrointestinal , Interleucina 22 , Camundongos Knockout , Animais , Camundongos , Infecções por Enterobacteriaceae/imunologia , Infecções por Enterobacteriaceae/microbiologia , Infecções por Enterobacteriaceae/prevenção & controle , Receptores de Interleucina/metabolismo , Receptores de Interleucina/genética , Interleucinas/metabolismo , Camundongos Endogâmicos C57BL , Infecções por Clostridium/imunologia , Infecções por Clostridium/microbiologia , Infecções por Clostridium/prevenção & controle
7.
Development ; 150(4)2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36786332

RESUMO

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.


Assuntos
Integrases , Recombinases , Camundongos , Animais , Técnicas de Inativação de Genes , Integrases/metabolismo , Recombinases/genética , Recombinases/metabolismo , Transgenes , Encéfalo/metabolismo , Camundongos Transgênicos
8.
Development ; 149(22)2022 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-36305473

RESUMO

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.


Assuntos
Folículo Piloso , Proteínas Wnt , Animais , Camundongos , Polaridade Celular/genética , Folículo Piloso/metabolismo , Transdução de Sinais/genética , Pele/metabolismo , Proteínas Wnt/genética , Proteínas Wnt/metabolismo , Proteína Wnt-5a/genética , Proteína Wnt-5a/metabolismo
9.
Cereb Cortex ; 34(4)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38602740

RESUMO

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.


Assuntos
Função Executiva , Exercício Físico , Humanos , Memória de Curto Prazo , Circulação Cerebrovascular , Córtex Pré-Frontal Dorsolateral
10.
Nucleic Acids Res ; 51(21): 11717-11731, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-37843130

RESUMO

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.


Assuntos
Replicação do DNA , Rad51 Recombinase , Linhagem Celular , Cromossomos/metabolismo , DNA/genética , DNA/metabolismo , Nucleoproteínas/genética , Rad51 Recombinase/genética , Rad51 Recombinase/metabolismo , Humanos
11.
J Biol Chem ; 299(1): 102728, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36410433

RESUMO

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.


Assuntos
Síndrome de Smith-Magenis , Camundongos , Animais , Síndrome de Smith-Magenis/genética , Síndrome de Smith-Magenis/terapia , Síndrome de Smith-Magenis/metabolismo , Transativadores/genética , Transativadores/metabolismo , Dependovirus/genética , Dependovirus/metabolismo , Haploinsuficiência , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Obesidade/genética
12.
BMC Plant Biol ; 24(1): 155, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38424508

RESUMO

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.


Assuntos
Resistência à Doença , Glycine max , Glycine max/genética , RNA-Seq , Alelos , Mapeamento Cromossômico/métodos , Fenótipo , Resistência à Doença/genética , Erysiphe , Doenças das Plantas/genética
13.
Small ; 20(16): e2307523, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38018331

RESUMO

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.


Assuntos
Separação de Fases , Pele , Humanos , Preparações de Ação Retardada/farmacologia , Administração Cutânea , Porosidade , Sistemas de Liberação de Medicamentos/métodos , Agulhas
14.
Small ; 20(8): e2304693, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37822153

RESUMO

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.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Neoplasias , Humanos , Ouro/química , Esferoides Celulares , Nanopartículas/química , Microscopia
15.
Plant Cell Environ ; 47(6): 2011-2026, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38392921

RESUMO

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.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Arabidopsis/fisiologia , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Plantas Geneticamente Modificadas , Regulação da Expressão Gênica de Plantas , Estresse Fisiológico/genética , Mutagênese Insercional/genética , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo
16.
Respir Res ; 25(1): 65, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38317222

RESUMO

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.


Assuntos
Pneumopatias , Neoplasias Pulmonares , Humanos , Pneumopatias/diagnóstico , Broncoscopia , Biópsia Guiada por Imagem , Neoplasias Pulmonares/patologia , Biópsia , Tomografia Computadorizada de Feixe Cônico , Fluoroscopia , Estudos Retrospectivos
17.
Diabetes Metab Res Rev ; 40(2): e3775, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38340046

RESUMO

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.


Assuntos
Fibrilação Atrial , Demência , Diabetes Mellitus Tipo 2 , Diabetes Mellitus , Inibidores da Dipeptidil Peptidase IV , Inibidores do Transportador 2 de Sódio-Glicose , Acidente Vascular Cerebral , Simportadores , Humanos , Fibrilação Atrial/complicações , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/epidemiologia , Administração Oral , Estudos de Coortes , Anticoagulantes , Inibidores da Dipeptidil Peptidase IV/uso terapêutico , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Demência/epidemiologia , Demência/prevenção & controle , Glucose , Sódio , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes , Estudos Retrospectivos
18.
Nat Chem Biol ; 18(11): 1196-1203, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35982227

RESUMO

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.


Assuntos
Receptores Acoplados a Proteínas G , Transdução de Sinais , Humanos , Masculino , Microscopia Crioeletrônica , Sulfato de Desidroepiandrosterona , Desoxicorticosterona , Ligantes , Receptores Acoplados a Proteínas G/química
19.
Environ Sci Technol ; 58(23): 9980-9990, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38819024

RESUMO

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.


Assuntos
Exposição Materna , Mecônio , Material Particulado , Humanos , Feminino , Mecônio/química , Gravidez , Estudos de Coortes , Recém-Nascido , Adulto , Poluentes Atmosféricos
20.
Bioorg Med Chem ; 109: 117792, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38897139

RESUMO

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.


Assuntos
Antineoplásicos , Apoptose , Ciclo Celular , Proliferação de Células , Ensaios de Seleção de Medicamentos Antitumorais , Transição Epitelial-Mesenquimal , Inibidores de Histona Desacetilases , Peixe-Zebra , Inibidores de Histona Desacetilases/farmacologia , Inibidores de Histona Desacetilases/química , Inibidores de Histona Desacetilases/síntese química , Humanos , Apoptose/efeitos dos fármacos , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Animais , Ciclo Celular/efeitos dos fármacos , Relação Estrutura-Atividade , Proliferação de Células/efeitos dos fármacos , Estrutura Molecular , Relação Dose-Resposta a Droga , Linhagem Celular Tumoral , Histona Desacetilases/metabolismo
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