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1.
Chem Soc Rev ; 53(4): 1892-1914, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38230701

RESUMO

Molecular assembly is the process of organizing individual molecules into larger structures and complex systems. The self-assembly approach is predominantly utilized in creating artificial molecular assemblies, and was believed to be the primary mode of molecular assembly in living organisms as well. However, it has been shown that the assembly of many biological complexes is "catalysed" by other molecules, rather than relying solely on self-assembly. In this review, we summarize these catalysed-assembly (catassembly) phenomena in living organisms and systematically analyse their mechanisms. We then expand on these phenomena and discuss related concepts, including catalysed-disassembly and catalysed-reassembly. Catassembly proves to be an efficient and highly selective strategy for synergistically controlling and manipulating various noncovalent interactions, especially in hierarchical molecular assemblies. Overreliance on self-assembly may, to some extent, hinder the advancement of artificial molecular assembly with powerful features. Furthermore, inspired by the biological catassembly phenomena, we propose guidelines for designing artificial catassembly systems and developing characterization and theoretical methods, and review pioneering works along this new direction. Overall, this approach may broaden and deepen our understanding of molecular assembly, enabling the construction and control of intelligent assembly systems with advanced functionality.

2.
Cancer Sci ; 115(1): 83-93, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37985391

RESUMO

Autoantibodies (AAbs) in the blood of colorectal cancer (CRC) patients have been evaluated for tumor detection. However, it remains uncertain whether these AAbs are specific to tumor-associated antigens. In this study, we explored the IgG and IgM autoantibody repertoires in both the in situ tissue microenvironment and peripheral blood as potential tumor-specific biomarkers. We applied high-density protein arrays to profile AAbs in the tumor-infiltrating lymphocyte supernatants and corresponding serum from four patients with CRC, as well as in the serum of three noncancer controls. Our findings revealed that there were more reactive IgM AAbs than IgG in both the cell supernatant and corresponding serum, with a difference of approximately 3-5 times. Immunoglobulin G was predominant in the serum, while IgM was more abundant in the cell supernatant. We identified a range of AAbs present in both the supernatant and the corresponding serum, numbering between 432 and 780, with an average of 53.3% shared. Only 4.7% (n = 23) and 0.2% (n = 2) of reactive antigens for IgG and IgM AAbs, respectively, were specific to CRC. Ultimately, we compiled a list of 19 IgG AAb targets as potential tumor-specific AAb candidates. Autoantibodies against one of the top candidates, p15INK4b-related sequence/regulation of nuclear pre-mRNA domain-containing protein 1A (RPRD1A), were significantly elevated in 53 CRC patients compared to 119 controls (p < 0.0001). The project revealed that tissue-derived IgG AAbs, rather than IgM, are the primary source of tumor-specific AAbs in peripheral blood. It also identified potential tumor-specific AAbs that could be applied for noninvasive screening of CRC.


Assuntos
Autoanticorpos , Neoplasias Colorretais , Humanos , Biomarcadores Tumorais , Imunoglobulina G , Imunoglobulina M , Microambiente Tumoral , Proteínas Repressoras , Proteínas de Ciclo Celular
3.
Small ; 20(7): e2306457, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37803917

RESUMO

As a main cause of serious cardiovascular diseases, atherosclerosis is characterized by deposited lipid and cholesterol crystals (CCs), which is considered as a great challenge to the current treatments. In this study, a dual-track reverse cholesterol transport strategy is used to overcome the cumulative CCs in the atherosclerotic lesions via a targeting nanoplatform named as LPLCH. Endowed with the active targeting ability to the plaques, the nanoparticles can be efficiently internalized and achieve a pH-triggered charge conversion for the escape from lysosomes. During this procedure, the liver X receptor (LXR) agonists loaded in nanoparticles are replaced by the deposited lysosomal CCs, leading to a LXR mediated up-regulation of ATP-binding cassette transporte ABCA1/G1 with the local CCs carrying at the same time. Thus, the cumulative CCs are removed in a dual-track way of ABCA1/G1 mediated efflux and nanoparticle-based carrying. The in vivo investigations indicate that LPLCH exhibits a favorable inhibition on the plaque progression and a further reversal of formed lesions when under a healthy diet. And the RNA-sequencing suggests that the cholesterol transport also synergistically activates the anti-inflammation effect. The dual-track reverse cholesterol transport strategy performed by LPLCH delivers an exciting candidate for the effective inhibition and degradation of atherosclerosis.


Assuntos
Aterosclerose , Placa Aterosclerótica , Humanos , Aterosclerose/tratamento farmacológico , Placa Aterosclerótica/tratamento farmacológico , Placa Aterosclerótica/patologia , Colesterol/metabolismo , Transporte Biológico
4.
Small ; : e2310082, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38470193

RESUMO

Electrochemical conversion of nitrate, a prevalent water pollutant, to ammonia (NH3 ) is a delocalized and green path for NH3 production. Despite the existence of different nitrate reduction pathways, selectively directing the reaction pathway on the road to NH3 is now hindered by the absence of efficient catalysts. Single-atom catalysts (SACs) are extensively investigated in a wide range of catalytic processes. However, their application in electrocatalytic nitrate reduction reaction (NO3 - RR) to NH3 is infrequent, mostly due to their pronounced inclination toward hydrogen evolution reaction (HER). Here, Ni single atoms on the electrochemically active carrier boron, nitrogen doped-graphene (BNG) matrix to modulate the atomic coordination structure through a boron-spanning strategy to enhance the performance of NO3 - RR is designed. Density functional theory (DFT) study proposes that BNG supports with ionic characteristics, offer a surplus electric field effect as compared to N-doped graphene, which can ease the nitrate adsorption. Consistent with the theoretical studies, the as-obtained NiSA@BNG shows higher catalytic activity with a maximal NH3 yield rate of 168 µg h-1  cm-2 along with Faradaic efficiency of 95% and promising electrochemical stability. This study reveals novel ways to rationally fabricate SACs' atomic coordination structure with tunable electronic properties to enhance electrocatalytic performance.

5.
Appl Environ Microbiol ; 90(3): e0225623, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38415624

RESUMO

The last step of the initiation phase of fatty acid biosynthesis in most bacteria is catalyzed by the 3-ketoacyl-acyl carrier protein (ACP) synthase III (FabH). Pseudomonas syringae pv. syringae strain B728a encodes two FabH homologs, Psyr_3467 and Psyr_3830, which we designated PssFabH1 and PssFabH2, respectively. Here, we explored the roles of these two 3-ketoacyl-ACP synthase (KAS) III proteins. We found that PssFabH1 is similar to the Escherichia coli FabH in using acetyl-acetyl-coenzyme A (CoA ) as a substrate in vitro, whereas PssFabH2 uses acyl-CoAs (C4-C10) or acyl-ACPs (C6-C10). Mutant analysis showed that neither KAS III protein is essential for the de novo fatty acid synthesis and cell growth. Loss of PssFabH1 reduced the production of an acyl homoserine lactone (AHL) quorum-sensing signal, and this production was partially restored by overexpressing FabH homologs from other bacteria. AHL production was also restored by inhibiting fatty acid elongation and providing exogenous butyric acid. Deletion of PssFabH1 supports the redirection of acyl-ACP toward biosurfactant synthesis, which in turn enhances swarming motility. Our study revealed that PssFabH1 is an atypical KAS III protein that represents a new KAS III clade that functions in providing a critical fatty acid precursor, butyryl-ACP, for AHL synthesis.IMPORTANCEAcyl homoserine lactones (AHLs) are important quorum-sensing compounds in Gram-negative bacteria. Although their formation requires acylated acyl carrier proteins (ACPs), how the acylated intermediate is shunted from cellular fatty acid synthesis to AHL synthesis is not known. Here, we provide in vivo evidence that Pseudomonas syringae strain B728a uses the enzyme PssFabH1 to provide the critical fatty acid precursor butyryl-ACP for AHL synthesis. Loss of PssFabH1 reduces the diversion of butyryl-ACP to AHL, enabling the accumulation of acyl-ACP for synthesis of biosurfactants that contribute to bacterial swarming motility. We report that PssFabH1 and PssFabH2 each encode a 3-ketoacyl-acyl carrier protein synthase (KAS) III in P. syringae B728a. Whereas PssFabH2 is able to function in redirecting intermediates from ß-oxidation to fatty acid synthesis, PssFabH1 is an atypical KAS III protein that represents a new KAS III clade based on its sequence, non-involvement in cell growth, and novel role in AHL synthesis.


Assuntos
3-Oxoacil-(Proteína de Transporte de Acila) Sintase , Acil-Butirolactonas , Pseudomonas syringae/genética , Pseudomonas syringae/metabolismo , 3-Oxoacil-(Proteína de Transporte de Acila) Sintase/genética , 3-Oxoacil-(Proteína de Transporte de Acila) Sintase/química , 3-Oxoacil-(Proteína de Transporte de Acila) Sintase/metabolismo , Ácidos Graxos/metabolismo , Bactérias/metabolismo , Escherichia coli/metabolismo , Acetilcoenzima A/metabolismo
6.
Plant Cell ; 33(7): 2360-2374, 2021 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-33871651

RESUMO

Light functions as the primary environmental stimulus and brassinosteroids (BRs) as important endogenous growth regulators throughout the plant lifecycle. Photomorphogenesis involves a series of vital developmental processes that require the suppression of BR-mediated seedling growth, but the mechanism underlying the light-controlled regulation of the BR pathway remains unclear. Here, we reveal that nuclear factor YC proteins (NF-YCs) function as essential repressors of the BR pathway during light-controlled hypocotyl growth in Arabidopsis thaliana. In the light, NF-YCs inhibit BR biosynthesis by directly targeting the promoter of the BR biosynthesis gene BR6ox2 and repressing its transcription. NF-YCs also interact with BIN2, a critical repressor of BR signaling, and facilitate its stabilization by promoting its Tyr200 autophosphorylation, thus inhibiting the BR signaling pathway. Consistently, loss-of-function mutants of NF-YCs show etiolated growth and constitutive BR responses, even in the light. Our findings uncover a dual role of NF-YCs in repressing BR biosynthesis and signaling, providing mechanistic insights into how light antagonizes the BR pathway to ensure photomorphogenic growth in Arabidopsis.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Arabidopsis/genética , Brassinosteroides/metabolismo , Regulação da Expressão Gênica de Plantas/fisiologia , Hipocótilo/metabolismo , Hipocótilo/fisiologia , Transdução de Sinais/fisiologia
7.
Plant Cell ; 33(1): 153-171, 2021 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-33751092

RESUMO

Plants have evolved precise mechanisms to optimize immune responses against pathogens. ENHANCED DISEASE SUSCEPTIBILITY 1 (EDS1) plays a vital role in plant innate immunity by regulating basal resistance and effector-triggered immunity. Nucleocytoplasmic trafficking of EDS1 is required for resistance reinforcement, but the molecular mechanism remains elusive. Here, we show that EDS1-INTERACTING J PROTEIN1 (EIJ1), which acts as a DnaJ protein-like chaperone in response to pathogen infection, functions as an essential negative regulator of plant immunity by interacting with EDS1. The loss-of-function mutation of EIJ1 did not affect plant growth but significantly enhanced pathogen resistance. Upon pathogen infection, EIJ1 relocalized from the chloroplast to the cytoplasm, where it interacted with EDS1, thereby restricting pathogen-triggered trafficking of EDS1 to the nucleus and compromising resistance at an early infection stage. During disease development, EIJ1 was gradually degraded, allowing the nuclear accumulation of EDS1 for transcriptional resistance reinforcement. The avirulent strain Pst DC3000 (AvrRps4) abolished the repressive action of EIJ1 by rapidly inducing its degradation in the effector-triggered immunity response. Thus, our findings show that EIJ1 is an essential EDS1-dependent negative regulator of innate plant immunity and provide a mechanistic understanding of how the nuclear versus cytoplasmic distribution of EDS1 is regulated during the immune response.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Proteínas de Ligação a DNA/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Ligação a DNA/genética , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Imunidade Vegetal/genética , Imunidade Vegetal/fisiologia , Transdução de Sinais/genética , Transdução de Sinais/fisiologia
8.
Phys Rev Lett ; 132(10): 103201, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38518314

RESUMO

We explored the collision-induced vibrational decoherence of singly ionized D_{2} molecules inside a helium nanodroplet. By using the pump-probe reaction microscopy with few-cycle laser pulses, we captured in real time the collision-induced ultrafast dissipation of vibrational nuclear wave packet dynamics of D_{2}^{+} ion embedded in the droplet. Because of the strong coupling of excited molecular cations with the surrounding solvent, the vibrational coherence of D_{2}^{+} in the droplet interior only lasts for a few vibrational periods and completely collapses within 140 fs. The observed ultrafast coherence loss is distinct from that of isolated D_{2}^{+} in the gas phase, where the vibrational coherence persists for a long time with periodic quantum revivals. Our findings underscore the crucial role of ultrafast collisional dissipation in shaping the molecular decoherence and solvation dynamics during solution chemical reactions, particularly when the solute molecules are predominantly in ionic states.

9.
Phys Rev Lett ; 132(3): 033201, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38307062

RESUMO

Recent advances in laser technology have enabled tremendous progress in light-induced molecular reactions, at the heart of which the breaking and formation of chemical bonds are located. Such progress has been greatly facilitated by the development of an accurate quantum-mechanical simulation method, which, however, does not necessarily accompany clear dynamical scenarios and is rather computationally heavy. Here, we develop a wave-packet surface propagation (WASP) approach to describe the molecular bond-breaking dynamics from a hybrid quantum-classical perspective. Via the introduction of quantum elements including state transitions and phase accumulations to the Newtonian propagation of the nuclear wave packet, the WASP approach naturally comes with intuitive physical scenarios and accuracies. It is carefully benchmarked with the H_{2}^{+} molecule and is shown to be capable of precisely reproducing experimental observations. The WASP method is promising for the intuitive visualization of light-induced molecular dynamics and is straightforward extensible towards complex molecules.

10.
FASEB J ; 37(6): e22955, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37159387

RESUMO

The pathogenesis of allergic rhinitis (AR)-related olfactory dysfunction (OD) remains unknown. Inhibiting microglial response in olfactory bulb (OB) can ameliorate AR-related OD, but no precise targets have been available. In this study, we established a mouse model of ovalbumin (OVA)-induced AR and combined with the application of P2X7 receptor (P2X7R)-specific antagonists and cell culture in conditioned medium to investigate the role and mechanism of OB microglial P2X7R in AR-related OD. Serum IgE and IL-5 levels determined via ELISA and federated the number of nose-scratching to affirm the success of OVA-induced AR mouse model. Buried food pellet test was used to evaluate the olfactory function of mice. The changes of IBA1, GFAP, P2X7R, IL-1ß, IL-1Ra, and CASPASE 1 were detected by quantitative polymerase chain reaction and western blotting. The levels of adenosine triphosphate (ATP) were determined by the commercialized kit. The morphological changes of microglia were assessed using immunofluorescence staining and Sholl analysis. Findings showed that AR-related OD was associated with OB microglia-mediated imbalance between IL-1ß and IL-1Ra. Treatment with BBG improved the olfactory function in AR mice with restoring the balance between IL-1ß and IL-1Ra. In vitro, the conditioned medium obtained after HNEpC treatment with Der p1 could activate HMC3 to arise inflammatory reaction basing on "ATP-P2X7R-Caspase 1" axis, while inhibition of its P2X7R suppressed the reaction. In brief, microglial P2X7R in OB is a direct effector molecule in AR-related OD and inhibition of it may be a new strategy for the treatment of AR-related OD.


Assuntos
Transtornos do Olfato , Receptores Purinérgicos P2X7 , Rinite Alérgica , Animais , Camundongos , Trifosfato de Adenosina , Caspase 1 , Meios de Cultivo Condicionados , Modelos Animais de Doenças , Proteína Antagonista do Receptor de Interleucina 1 , Microglia , Bulbo Olfatório , Ovalbumina , Receptores Purinérgicos P2X7/genética , Rinite Alérgica/complicações
11.
Mol Breed ; 44(3): 24, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38495646

RESUMO

Sorghum is an important food crop commonly used for brewing, feed, and bioenergy. Certain genotypes of sorghum contain high concentrations of condensed tannins in seeds, which are beneficial, such as protecting grains from herbivore bird pests, but also impair grain quality and digestibility. Previously, we identified Tannin1 and Tannin2, each with three recessive causal alleles, regulate tannin absence in sorghum. In this study, via characterizing 421 sorghum accessions, we further identified three novel recessive alleles from these two genes. The tan1-d allele contains a 12-bp deletion at position 659 nt and the tan1-e allele contains a 10-bp deletion at position 771 nt in Tannin1. The tan2-d allele contains a C-to-T transition, which results in a premature stop codon before the bHLH domain in Tannin2, and was predominantly selected in China. We further developed KASP assays targeting these identified recessive alleles to efficiently genotype large populations. These studies provide new insights in sorghum domestication and convenient tools for breeding programs. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-024-01463-y.

12.
J Phys Chem A ; 128(2): 401-412, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38181198

RESUMO

An ultrafast intense laser field is one of the most important tools to observe and manipulate electronic and nuclear dynamics with subcycle precision in highly nonlinear light-matter interactions, which provides access to attosecond chemistry and physics. In this review, we briefly summarize the protocol of attosecond chronoscopy and its application in probing the attosecond photoemission dynamics from atoms and molecules. We also review the control schemes of attosecond electron motion in atoms and molecules as well as molecular bond formation and cleavage with the assistance of tailored femtosecond laser fields.

13.
J Craniofac Surg ; 35(4): 1289-1291, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38483294

RESUMO

OBJECTIVE: An improved method of treating inwardly dislocated mandibular extracapsular condylar fracture-three times titanium plate gradual fixation method was introduced, and the clinical efficacy of this method was evaluated. METHODS: Twenty patients with extracapsular condylar fractures who underwent surgical treatment using the three times titanium plate gradual restoration and fixation method in the Department of Oral Craniomaxillofacial Surgery of the Ninth People's Hospital of Shanghai from November 2020 to June 2023 were selected as the study subjects. RESULTS: After condylar restoration 22 sides reached healing and 1 side was basically healed; in 3 months after the operation, the degree of opening the mouth and the type of the opening of the mouth reached normal, and 1 case had mildly poor occlusion, which required to be further adjusted through orthodontics, and there was no temporomandibular function disorder or facial nerve function damage. CONCLUSION: Three times of gradual fixation with a titanium plate can make the condylar process achieve precise and stable repositioning, and make the surgical process orderly, and it is a kind of reliable fixation method for extracapsular condylar fractures.


Assuntos
Placas Ósseas , Fixação Interna de Fraturas , Côndilo Mandibular , Fraturas Mandibulares , Titânio , Humanos , Fraturas Mandibulares/cirurgia , Côndilo Mandibular/lesões , Côndilo Mandibular/cirurgia , Masculino , Fixação Interna de Fraturas/métodos , Fixação Interna de Fraturas/instrumentação , Feminino , Adulto , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem , Adolescente
14.
J Craniofac Surg ; 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38727237

RESUMO

OBJECTIVE: In a retrospective study of the effects of different treatment modalities of condylar fractures in childhood on mandibular symmetry and temporomandibular function, the cases selected for this article were adult patients who had sustained a condylar fracture in childhood. The aim was to investigate the effects of condylar fractures in children on the development and function of the mandible and their specific manifestations after the completion of mandibular development. METHODS: According to the different treatment modalities, the patients were divided into the conservative treatment group and the open surgical treatment group, and the effects of the 2 treatment modalities on the patients' condylar healing, the difference in growth ability, and the symmetry of the jaws were evaluated. The effects of different treatment modalities of children's condylar fracture on the growth, development, and function of the mandible were investigated using the Ai and Di, the grading of the imaging results, and the 3-dimensional CT fixation measurements from the aspects of both clinical examination and imaging examination. RESULTS: The 2 groups had condylar malalignment and condylar morphology abnormality, and there was one case of joint ankylosis in the surgical treatment group. There was a statistical difference in the evaluation of condylar reconstruction between the 2 groups, and the condylar reconstruction in the surgical treatment group was better than that in the conservative treatment, and there was a statistical difference between the condylar length, condylar width, condylar height, and depth of TMJ fossa between the healthy side and the affected side in the closed treatment group. There was a statistical difference in the height of the mandibular ascending branch between the healthy side and the affected side, and the unilateral condylar fracture was treated conservatively; the difference in the bony chin point deviation between the 2 groups was not statistically significant. CONCLUSION: In children, after conservative treatment of condylar fracture, the growth of condylar process is poor, and the condylar shape and position are not as good as surgical repositioning, but through the proliferation of temporomandibular joint fossa, it can make up for the insufficient height of condylar process, which has no effect on the symmetry of the mandible, and the surgical treatment can achieve good anatomical repositioning, which has a greater effect on the symmetry of the mandible than the conservative treatment.

15.
J Lipid Res ; 64(5): 100367, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37011864

RESUMO

For the past 20 years, the majority of cell culture studies reported that increasing cholesterol level increases amyloid-ß (Aß) production. Conversely, other studies and genetic evidences support that cellular cholesterol loss leads to Aß generation. As a highly controversial issue in Alzheimer's disease pathogenesis, the apparent contradiction prompted us to again explore the role of cellular cholesterol in Aß production. Here, we adopted new neuronal and astrocytic cell models induced by 3ß-hydroxysterol-Δ24 reductase (DHCR24), which obviously differ from the widely used cell models with overexpressing amyloid precursor protein (APP) in the majority of previous studies. In neuronal and astrocytic cell model, we found that deficiency of cellular cholesterol by DHCR24 knockdown obviously increased intracellular and extracellular Aß generation. Importantly, in cell models with overexpressing APP, we found that APP overexpression could disrupt cellular cholesterol homeostasis and affect function of cells, coupled with the increase of APP ß-cleavage product, 99-residue transmembrane C-terminal domain. Therefore, we suppose the results derived from the APP knockin models will need to be re-evaluated. One rational explanation for the discrepancy between our outcomes and the previous studies could be attributed to the two different cell models. Mechanistically, we showed that cellular cholesterol loss obviously altered APP intracellular localization by affecting cholesterol-related trafficking protein of APP. Therefore, our outcomes strongly support cellular cholesterol loss by DHCR24 knockdown leads to Aß production.


Assuntos
Doença de Alzheimer , Oxirredutases atuantes sobre Doadores de Grupo CH-CH , Humanos , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Peptídeos beta-Amiloides/genética , Peptídeos beta-Amiloides/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Colesterol/metabolismo , Neurônios/metabolismo , Secretases da Proteína Precursora do Amiloide/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/genética , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/metabolismo
16.
Mol Plant Microbe Interact ; 36(2): 119-130, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36515967

RESUMO

Most bacteria use type II fatty acid synthesis (FAS) systems for synthesizing fatty acids, of which the conserved FabA-FabB pathway is considered to be crucial for unsaturated fatty acid (UFA) synthesis in gram-negative bacteria. Xanthomonas campestris pv. campestris, the phytopathogen of black rot disease in crucifers, produces higher quantities of UFAs under low-temperature conditions for increasing membrane fluidity. The fabA and fabB genes were identified in the X. campestris pv. campestris genome by BLAST analysis; however, the growth of the X. campestris pv. campestris fabA and fabB deletion mutants was comparable to that of the wild-type strain in nutrient and minimal media. The X. campestris pv. campestris ΔfabA and ΔfabB strains produced large quantities of UFAs and, altogether, these results indicated that the FabA-FabB pathway is not essential for growth or UFA synthesis in X. campestris pv. campestris. We also observed that the expression of X. campestris pv. campestris fabA and fabB restored the growth of the temperature-sensitive Escherichia coli fabA and fabB mutants CL104 and CY242, respectively, under non-permissive conditions. The in-vitro assays demonstrated that the FabA and FabB proteins of X. campestris pv. campestris catalyzed FAS. Our study also demonstrated that the production of diffusible signal factor family signals that mediate quorum sensing was higher in the X. campestris pv. campestris ΔfabA and ΔfabB strains and greatly reduced in the complementary strains, which exhibited reduced swimming motility and attenuated host-plant pathogenicity. [Formula: see text] Copyright © 2023 The Author(s). This is an open access article distributed under the CC BY 4.0 International license.


Assuntos
Xanthomonas campestris , Xanthomonas campestris/metabolismo , Ácidos Graxos/metabolismo , Escherichia coli/genética , Percepção de Quorum , Ácidos Graxos Insaturados/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo
17.
Pharmacogenet Genomics ; 33(1): 1-9, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36441170

RESUMO

OBJECTIVE: Bladder cancer is a highly prevalent disease worldwide. We aimed to investigate the effect of miRNA/mRNA signaling on bladder urothelial carcinoma (BUC). METHODS: MiRNA-139-3p wasselected from The Cancer Genome Atlas database, and its downstream target gene was predicted. The correlation between miRNA-139-3p and intersected mRNAs was analyzed. The mRNA expression levels of miRNA-139-3p and KIF18B in BUC were assayed via quantitative real-time polymerase chain reaction. Effects of miRNA-139-3p on cell proliferation, invasion, migration and cell cycle were detected via Cell Counting Kit-8, colony formation, transwell, wound healing and flow cytometry assays, respectively. Binding relationship between miRNA-139-3p and KIF18B was verified by dual-luciferase reporter gene detection. The protein expression levels of KIF18B, ß-catenin and Cyclin D1 were detected by Western blot. Rescue assays were performed for verifying the interaction among miRNA-139-3p, KIF18B and Wnt/ß-catenin signaling pathway, which revealed effects of miRNA-139-3p/KIF18B on BUC cells. RESULTS: MiRNA-139-3p was remarkably underexpressed, and KIF18B was dramatically overexpressed in BUC cells, respectively. It was also demonstrated that overexpressing miRNA-139-3p could prominently inhibit proliferation, invasion and migration of BUC, and block BUC cells at G0-G1 phase. Afterwards, we found that miRNA-139-3p could bind to KIF18B mRNA 3'UTR, and miRNA-139-3p had a negative regulatory effect with KIF18B. Subsequent experimental results presented that overexpressing KIF18B could reverse inhibitory effect of overexpressing miRNA-139-3p on BUC. Finally, this study also ascertained that miRNA-139-3p/KIF18B could repress oncogenic effects of BUC via modulating Wnt/ß-catenin signaling pathway. CONCLUSION: MiRNA-139-3p/KIF18B/Wnt/ß-catenin could significantly inhibit the malignant progression of BUC, and its targeting mechanism might provide an effective therapeutic target for BUC patients.


Assuntos
Carcinoma de Células de Transição , MicroRNAs , Neoplasias da Bexiga Urinária , Humanos , Neoplasias da Bexiga Urinária/genética , Bexiga Urinária , beta Catenina/genética , Via de Sinalização Wnt/genética , MicroRNAs/genética , RNA Mensageiro , Cinesinas/genética
18.
Anal Chem ; 95(45): 16435-16446, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37921449

RESUMO

Biomolecular characterization is essential in fields such as drug discovery, glycomics, and cell biology. This feature article focuses on the experimental use of quartz crystal microbalance with dissipation (QCM-D) as a powerful analytical technique to probe biological events ranging from biomacromolecular interactions and conformational changes of biomacromolecules to surface immobilization of biomacromolecules and cell morphological changes.

19.
J Neurosci Res ; 101(4): 480-491, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36564932

RESUMO

In addition to typical nasal symptoms, patients with allergic rhinitis (AR) will further lead to symptoms related to brain function such as hyposmia, anxiety, depression, cognitive impairment, memory loss, etc., which seriously affect the quality of life of patients and bring a heavy burden to the patient's family and society. Some scholars have speculated that there may be potential "nose-brain communication" mechanism in AR that rely on neuro-immunity. This mechanism plays an important role in AR-associated brain response process. However, no study has directly demonstrated which neural circuits will change in the connection between the nose and brain during the onset of AR, and the mechanism which underlines this question is also lack. Focusing on the topic of "nose-brain communication", this paper systematically summarizes the latest research progress between AR and related brain responses and discusses the mechanism of AR-related neurological phenotypes. Hope new diagnostic and therapeutic targets to ameliorate the brain function-related symptoms and improve the quality of life of AR patients will be developed.


Assuntos
Qualidade de Vida , Rinite Alérgica , Humanos , Rinite Alérgica/diagnóstico , Rinite Alérgica/terapia , Encéfalo
20.
Phys Rev Lett ; 130(14): 143203, 2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-37084425

RESUMO

We demonstrate that dissociative ionization of H_{2} can be fully manipulated in an angle-time-resolved fashion, employing a polarization-skewed (PS) laser pulse in which the polarization vector rotates. The leading and falling edges of the PS laser pulse, characterized by unfolded field polarization, trigger, sequentially, parallel and perpendicular transitions of stretching H_{2} molecules, respectively. These transitions result in counterintuitive proton ejections that deviate significantly from the laser polarization directions. Our findings demonstrate that the reaction pathways can be controlled through fine-tuning the time-dependent polarization of the PS laser pulse. The experimental results are well reproduced using an intuitive wave-packet surface propagation simulation method. This research highlights the potential of PS laser pulses as powerful tweezers to resolve and manipulate complex laser-molecule interactions.

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