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1.
Immunity ; 56(12): 2773-2789.e8, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-37992711

RESUMO

Although the gut microbiota can influence central nervous system (CNS) autoimmune diseases, the contribution of the intestinal epithelium to CNS autoimmunity is less clear. Here, we showed that intestinal epithelial dopamine D2 receptors (IEC DRD2) promoted sex-specific disease progression in an animal model of multiple sclerosis. Female mice lacking Drd2 selectively in intestinal epithelial cells showed a blunted inflammatory response in the CNS and reduced disease progression. In contrast, overexpression or activation of IEC DRD2 by phenylethylamine administration exacerbated disease severity. This was accompanied by altered lysozyme expression and gut microbiota composition, including reduced abundance of Lactobacillus species. Furthermore, treatment with N2-acetyl-L-lysine, a metabolite derived from Lactobacillus, suppressed microglial activation and neurodegeneration. Taken together, our study indicates that IEC DRD2 hyperactivity impacts gut microbial abundances and increases susceptibility to CNS autoimmune diseases in a female-biased manner, opening up future avenues for sex-specific interventions of CNS autoimmune diseases.


Assuntos
Doenças Autoimunes do Sistema Nervoso , Esclerose Múltipla , Masculino , Feminino , Camundongos , Animais , Esclerose Múltipla/metabolismo , Modelos Animais de Doenças , Transdução de Sinais , Progressão da Doença , Receptores Dopaminérgicos
2.
Mol Cell ; 84(18): 3438-3454.e8, 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39232583

RESUMO

Spreading of H3K27me3 is crucial for the maintenance of mitotically inheritable Polycomb-mediated chromatin silencing in animals and plants. However, how Polycomb repressive complex 2 (PRC2) accesses unmodified nucleosomes in spreading regions for spreading H3K27me3 remains unclear. Here, we show in Arabidopsis thaliana that the chromatin remodeler PICKLE (PKL) plays a specialized role in H3K27me3 spreading to safeguard cell identity during differentiation. PKL specifically localizes to H3K27me3 spreading regions but not to nucleation sites and physically associates with PRC2. Loss of PKL disrupts the occupancy of the PRC2 catalytic subunit CLF in spreading regions and leads to aberrant dedifferentiation. Nucleosome density increase endowed by the ATPase function of PKL ensures that unmodified nucleosomes are accessible to PRC2 catalytic activity for H3K27me3 spreading. Our findings demonstrate that PKL-dependent nucleosome compaction is critical for PRC2-mediated H3K27me3 read-and-write function in H3K27me3 spreading, thus revealing a mechanism by which repressive chromatin domains are established and propagated.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Diferenciação Celular , Montagem e Desmontagem da Cromatina , Histonas , Nucleossomos , Complexo Repressor Polycomb 2 , Nucleossomos/metabolismo , Nucleossomos/genética , Arabidopsis/genética , Arabidopsis/metabolismo , Histonas/metabolismo , Histonas/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Complexo Repressor Polycomb 2/metabolismo , Complexo Repressor Polycomb 2/genética , Regulação da Expressão Gênica de Plantas , Cromatina/metabolismo , Cromatina/genética
3.
Nature ; 617(7962): 717-723, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37225883

RESUMO

Flexible solar cells have a lot of market potential for application in photovoltaics integrated into buildings and wearable electronics because they are lightweight, shockproof and self-powered. Silicon solar cells have been successfully used in large power plants. However, despite the efforts made for more than 50 years, there has been no notable progress in the development of flexible silicon solar cells because of their rigidity1-4. Here we provide a strategy for fabricating large-scale, foldable silicon wafers and manufacturing flexible solar cells. A textured crystalline silicon wafer always starts to crack at the sharp channels between surface pyramids in the marginal region of the wafer. This fact enabled us to improve the flexibility of silicon wafers by blunting the pyramidal structure in the marginal regions. This edge-blunting technique enables commercial production of large-scale (>240 cm2), high-efficiency (>24%) silicon solar cells that can be rolled similarly to a sheet of paper. The cells retain 100% of their power conversion efficiency after 1,000 side-to-side bending cycles. After being assembled into large (>10,000 cm2) flexible modules, these cells retain 99.62% of their power after thermal cycling between -70 °C and 85 °C for 120 h. Furthermore, they retain 96.03% of their power after 20 min of exposure to air flow when attached to a soft gasbag, which models wind blowing during a violent storm.

4.
J Biol Chem ; : 107876, 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-39395794

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease worldwide. USP25 in adipocytes has been proven to be involved in insulin resistance, a noteworthy characteristic of NAFLD. However, the roles of USP25 in NAFLD remain unclear. In this study, we aimed to elucidate the role of USP25 in NAFLD. Hepatic USP25 protein levels were measured in NAFLD patients and models. USP25 expression was manipulated in both mice and cells to evaluate its role in NAFLD. A downstream target of USP25 in NAFLD progression was identified through proteomic profiling analyses and confirmed. Additionally, a USP25 inhibitor was used to determine whether USP25 could be a viable treatment target for NAFLD. We found that USP25 protein levels were significantly decreased in the livers of NAFLD patients and NAFLD model mice. USP25 protein levels were also decreased in both mouse primary hepatocytes and Huh7 cells treated with free fatty acids (FFAs). We also found that Usp25 knockout mice presented much more severe hepatic steatosis when they were fed a high-fat diet. Similarly, knocking down USP25 in Huh7 cell lines aggravated FFA-induced steatosis, whereas USP25 overexpression ameliorated FFA-induced steatosis in Huh7 cell lines. Further proteomic profiling revealed that the PPARα signaling pathway was a downstream target of USP25, which was confirmed in both mice and cell lines. Moreover, USP25 could stabilize PPARα by promoting its deubiquitination. Finally, a USP25 inhibitor exacerbated diet-induced steatosis in mice. In conclusion, USP25 may play a role in NAFLD through the PPARα signaling pathway and could be a potential therapeutic target for NAFLD.

5.
Mol Microbiol ; 122(2): 201-212, 2024 08.
Artigo em Inglês | MEDLINE | ID: mdl-38922722

RESUMO

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


Assuntos
Arseniato Redutases , Bacteroidetes , Domínio Catalítico , Oxirredução , Arseniato Redutases/metabolismo , Arseniato Redutases/genética , Arseniato Redutases/química , Bacteroidetes/enzimologia , Bacteroidetes/genética , Arseniatos/metabolismo , Cinética , Monoéster Fosfórico Hidrolases/metabolismo , Monoéster Fosfórico Hidrolases/genética , Monoéster Fosfórico Hidrolases/química , Catálise , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/química , Arsenitos/metabolismo
6.
Plant Cell ; 34(10): 3915-3935, 2022 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-35866997

RESUMO

PICKLE (PKL) is a chromodomain helicase DNA-binding domain 3 (CHD3) chromatin remodeler that plays essential roles in controlling the gene expression patterns that determine developmental identity in plants, but the molecular mechanisms through which PKL is recruited to its target genes remain elusive. Here, we define a cis-motif and trans-acting factors mechanism that governs the genomic occupancy profile of PKL in Arabidopsis thaliana. We show that two homologous trans-factors VIVIPAROUS1/ABI3-LIKE1 (VAL1) and VAL2 physically interact with PKL in vivo, localize extensively to PKL-occupied regions in the genome, and promote efficient PKL recruitment at thousands of target genes, including those involved in seed maturation. Transcriptome analysis and genetic interaction studies reveal a close cooperation of VAL1/VAL2 and PKL in regulating gene expression and developmental fate. We demonstrate that this recruitment operates at two master regulatory genes, ABSCISIC ACID INSENSITIVE3 and AGAMOUS-LIKE 15, to repress the seed maturation program and ensure the seed-to-seedling transition. Together, our work unveils a general rule through which the CHD3 chromatin remodeler PKL binds to its target chromatin in plants.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Ácido Abscísico/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Cromatina/genética , Cromatina/metabolismo , DNA/metabolismo , DNA Helicases/genética , DNA Helicases/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Sementes/genética , Transativadores/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
7.
Exp Cell Res ; 442(2): 114274, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39393753

RESUMO

Dysregulated adipokine production is an influencing factor for the homeostatic imbalance of tendons. High levels of serum leptin may be a potential link between increasing adiposity and tendinopathy, while the detailed mechanistic explanation was not well-defined. In this study, we investigated the regulatory role of leptin in the tendon stem/progenitor cells (TSPCs) and the molecular mechanism within, and determined the effect of high levels of leptin on tendon recovery. We demonstrated that leptin reduced the viability of isolated rat TSPCs in a dose-dependent way, accompanied with increased transdifferentiation and altered gene expression of a series of extracellular matrix (ECM) enzymatic modulators. Also, we found that leptin could dose-dependently promote TSPCs senescence, while exhibiting limited effect in apoptotic or autophagic induction. Mechanistic study evidenced that leptin treatment increased the AKT/mTOR signaling activity and elevated the expression of leptin receptor (LEPR) in TSPCs, without marked change in MAPK or STAT5 activation. Further, we confirmed that rapamycin treatment, but not AKT inhibition, effectively reduced the leptin-promoted TSPCs senescence. In a rat model with Achilles wounding, exposure to leptin profoundly delayed tendon healing, which was effectively rescued with rapamycin treatment. Our results suggested that leptin could cause intrinsic cellular deficits in TSPCs and impede tendon repair through the AKT/mTOR signaling pathway. These findings evidenced for an important role of elevated leptin levels in the care of tendinopathy and tendon tears.


Assuntos
Senescência Celular , Leptina , Proteínas Proto-Oncogênicas c-akt , Ratos Sprague-Dawley , Transdução de Sinais , Células-Tronco , Serina-Treonina Quinases TOR , Tendões , Animais , Leptina/metabolismo , Leptina/farmacologia , Serina-Treonina Quinases TOR/metabolismo , Serina-Treonina Quinases TOR/genética , Células-Tronco/metabolismo , Células-Tronco/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Senescência Celular/efeitos dos fármacos , Tendões/metabolismo , Tendões/efeitos dos fármacos , Tendões/citologia , Masculino , Células Cultivadas , Receptores para Leptina/metabolismo , Receptores para Leptina/genética , Cicatrização/efeitos dos fármacos
8.
BMC Biol ; 22(1): 132, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38835016

RESUMO

BACKGROUND: ARID1A, a subunit of the SWI/SNF chromatin remodeling complex, is thought to play a significant role both in tumor suppression and tumor initiation, which is highly dependent upon context. Previous studies have suggested that ARID1A deficiency may contribute to cancer development. The specific mechanisms of whether ARID1A loss affects tumorigenesis by RNA editing remain unclear. RESULTS: Our findings indicate that the deficiency of ARID1A leads to an increase in RNA editing levels and alterations in RNA editing categories mediated by adenosine deaminases acting on RNA 1 (ADAR1). ADAR1 edits the CDK13 gene at two previously unidentified sites, namely Q113R and K117R. Given the crucial role of CDK13 as a cyclin-dependent kinase, we further observed that ADAR1 deficiency results in changes in the cell cycle. Importantly, the sensitivity of ARID1A-deficient tumor cells to SR-4835, a CDK12/CDK13 inhibitor, suggests a promising therapeutic approach for individuals with ARID1A-mutant tumors. Knockdown of ADAR1 restored the sensitivity of ARID1A deficient cells to SR-4835 treatment. CONCLUSIONS: ARID1A deficiency promotes RNA editing of CDK13 by regulating ADAR1.


Assuntos
Adenosina Desaminase , Quinases Ciclina-Dependentes , Proteínas de Ligação a DNA , Edição de RNA , Proteínas de Ligação a RNA , Fatores de Transcrição , Adenosina Desaminase/metabolismo , Adenosina Desaminase/genética , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/genética , Humanos , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/genética , Quinases Ciclina-Dependentes/metabolismo , Quinases Ciclina-Dependentes/genética , Linhagem Celular Tumoral , Proteína Quinase CDC2
9.
BMC Genomics ; 25(1): 536, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38816704

RESUMO

BACKGROUND: The formation of pharmacologically active components in medicinal plants is significantly impacted by DNA methylation. However, the exact mechanisms through which DNA methylation regulates secondary metabolism remain incompletely understood. Research in model species has demonstrated that DNA methylation at the transcription factor binding site within functional gene promoters can impact the binding of transcription factors to target DNA, subsequently influencing gene expression. These findings suggest that the interaction between transcription factors and target DNA could be a significant mechanism through which DNA methylation regulates secondary metabolism in medicinal plants. RESULTS: This research conducted a comprehensive analysis of the NAC family in E. senticosus, encompassing genome-wide characterization and functional analysis. A total of 117 EsNAC genes were identified and phylogenetically divided into 15 subfamilies. Tandem duplications and chromosome segment duplications were found to be the primary replication modes of these genes. Motif 2 was identified as the core conserved motif of the genes, and the cis-acting elements, gene structures, and expression patterns of each EsNAC gene were different. EsJUB1, EsNAC047, EsNAC098, and EsNAC005 were significantly associated with the DNA methylation ratio in E. senticosus. These four genes were located in the nucleus or cytoplasm and exhibited transcriptional self-activation activity. DNA methylation in EsFPS, EsSS, and EsSE promoters significantly reduced their activity. The methyl groups added to cytosine directly hindered the binding of the promoters to EsJUB1, EsNAC047, EsNAC098, and EsNAC005 and altered the expression of EsFPS, EsSS, and EsSE genes, eventually leading to changes in saponin synthesis in E. senticosus. CONCLUSIONS: NAC transcription factors that are hindered from binding by methylated DNA are found in E. senticosus. The incapacity of these NACs to bind to the promoter of the methylated saponin synthase gene leads to subsequent alterations in gene expression and saponin synthesis. This research is the initial evidence showcasing the involvement of EsNAC in governing the impact of DNA methylation on saponin production in E. senticosus.


Assuntos
Metilação de DNA , Eleutherococcus , Proteínas de Plantas , Regiões Promotoras Genéticas , Saponinas , Fatores de Transcrição , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Eleutherococcus/genética , Eleutherococcus/metabolismo , Saponinas/biossíntese , Saponinas/genética , Regulação da Expressão Gênica de Plantas , Filogenia
10.
J Am Chem Soc ; 146(11): 7373-7385, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38433410

RESUMO

Organic-inorganic atomically precise nanoclusters provide indispensable building blocks for establishing structure-property links in hybrid condensed matter. However, robust glasses of ligand-protected nanocluster solids have yet to be demonstrated. Herein, we show [Cu4I4(PR3)4] cubane nanoclusters coordinated by phosphine ligands (PR3) form robust melt-quenched glasses in air with reversible crystal-liquid-glass transitions. Protective phosphine ligands critically influence the glass formation mechanism, modulating the glasses' physical properties. A hybrid glass utilizing ethyldiphenylphosphine-based nanoclusters, [Cu4I4(PPh2Et)4], exhibits superb optical properties, including >90% transmission in both visible and near-infrared wavelengths, negligible self-absorption, near-unity quantum yield, and high light yield. Experimental and theoretical analyses demonstrate the structural integrity of the [Cu4I4(PPh2Et)4] nanocluster, i.e., iodine-bridged tetranuclear cubane, has been fully preserved in the glass state. The strong internanocluster CH-π interactions found in the [Cu4I4(PPh2Et)4] glass and subsequently reduced structural vibration account for its enhanced luminescence properties. Moreover, this highly transparent glass enables performant X-ray imaging and low-loss waveguiding in fibers drawn above the glass transition. The discovery of "nanocluster glass" opens avenues for unraveling glass formation mechanisms and designing novel luminescent glasses of well-defined building blocks for advanced photonics.

11.
J Am Chem Soc ; 146(6): 4144-4152, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38315569

RESUMO

Circularly polarized light-emitting diodes (CP-LEDs) are critical for next-generation optical technologies, ranging from holography to quantum information processing. Currently deployed chiral luminescent materials, with their intricate synthesis and processing and limited efficiency, are the main bottleneck for CP-LEDs. Chiral metal nanoclusters (MNCs) are potential CP-LED materials, given their ease of synthesis and processability as well as diverse structures and excited states. However, their films are usually plagued by inferior electronic quality and aggregation-caused photoluminescence quenching, necessitating their incorporation into host materials; without such a scheme, MNC-based LEDs exhibit external quantum efficiencies (EQEs) < 10%. Herein, we achieve an efficiency leap for both CP-LEDs and cluster-based LEDs by using novel chiral MNCs with aggregation-induced emission enhancement. CP-LEDs using enantiopure MNC films attain EQEs of up to 23.5%. Furthermore, by incorporating host materials, the devices yield record EQEs of up to 36.5% for both CP-LEDs and cluster-based LEDs, along with electroluminescence dissymmetry factors (|gEL|) of around 1.0 × 10-3. These findings open a new avenue for advancing chiral light sources for next-generation optoelectronics.

12.
Mol Microbiol ; 119(4): 471-491, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36760021

RESUMO

The chromatin structure is generally regulated by chromatin remodelers and histone modifiers, which affect DNA replication, repair, and levels of transcription. The first identified histone acetyltransferase was Hat1/KAT1, which belongs to lysine (K) acetyltransferases. The catalytic subunit Hat1 and the regulatory subunit Hat2 make up the core HAT1 complex. In this study, the results of tandem affinity purification and mass spectrometry and bimolecular fluorescence complementation proved that the Penicillium oxalicum PoHat1-Hat2 is the transcriptional cofactor of the sequence-specific transcription factor PoAmyR, a transcription activator essential for the transcription of amylase gene. ChIP-qPCR results demonstrated that the complex PoHat1-Hat2 is recruited by PoAmyR to the promoters of prominent amylase genes Poamy13A and Poamy15A and performs histone H4 lysine12 acetylation. The result of the yeast two-hybrid test indicated that PoHat2 is the subunit that directly interacts with PoAmyR. PoHat1-Hat2 acts as the molecular brake of the PoAmyR-regulating transcription of amylase genes. A putative model for amylase gene regulation by PoAmyR-Hat2-Hat1 was constructed. Our paper is the first report that the Hat1-Hat2 complex acts as a cofactor for sequence-specific TF to regulate gene expression and explains the mechanism of TF AmyR regulating amylase genes expression.


Assuntos
Proteínas Fúngicas , Histona Acetiltransferases , Penicillium , Fatores de Transcrição , Acetilação , Cromatina , Expressão Gênica , Histona Acetiltransferases/genética , Histona Acetiltransferases/metabolismo , Histonas/genética , Histonas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Penicillium/metabolismo , Proteínas Fúngicas/metabolismo
13.
Anal Chem ; 96(23): 9636-9642, 2024 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-38808501

RESUMO

Organophosphate pesticides (OPs) are widely utilized in agricultural production, and the residues threaten public health and environmental safety due to their toxicity. Herein, a novel and simple DNA aptamer-based sensor has been fabricated for the rapid, visual, and quantitative detection of profenofos and isocarbophos. The proposed DNA aptamers with a G-quadruplex spatial structure could be recognized by SYBR Green I (SG-I), resulting in strong green fluorescence emitted by SG-I. The DNA aptamers exhibit a higher specific binding ability to target OP molecules through aromatic ring stacking, disrupting the interaction between SG-I and DNA aptamers to induce green fluorescence quenching. Meanwhile, the fluorescence wavelength of G-quadruplex fluorescence emission peaks changes, accompanied by an obvious fluorescence variation from green to blue. SG-I-modified aptasensor without any additive reference fluorescence units for use in multicolor fluorescence assay for selective monitoring of OPs was first developed. The developed aptasensor provides a favorable linear range from 0 to 200 nM, with a low detection limit of 2.48 and 3.01 nM for profenofos and isocarbophos, respectively. Moreover, it offers high selectivity and stability in real sample detection with high recoveries. Then, a self-designed portable smartphone sensing platform was successfully used for quantitative result outputs, demonstrating experience in designing a neotype sensing strategy for point-of-care pesticide monitoring.


Assuntos
Aptâmeros de Nucleotídeos , Benzotiazóis , Diaminas , Corantes Fluorescentes , Compostos Orgânicos , Praguicidas , Quinolinas , Espectrometria de Fluorescência , Aptâmeros de Nucleotídeos/química , Quinolinas/química , Praguicidas/análise , Diaminas/química , Corantes Fluorescentes/química , Benzotiazóis/química , Compostos Orgânicos/química , Técnicas Biossensoriais/métodos , Limite de Detecção , Quadruplex G , Malation/análogos & derivados
14.
Small ; 20(13): e2308945, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37948432

RESUMO

The family of metal-free molecular perovskites, an emerging novel class of eco-friendly semiconductor, welcomes a new member with a unique 1D hexagonal perovskite structure. Lowering dimensionality at molecular level is a facile strategy for crystal structure conversion, optoelectronic property regulation, and device performance optimization. Herein, the study reports the design, synthesis, packing structure, and photophysical properties of the 1D metal-free molecular perovskite-related single crystal, rac-3APD-NH4I3(rac-3APD= racemic-3-Aminopiperidinium), that features a quantum wire structure formed by infinite chains of face-sharing NH4I6 octahedra, enabling strong quantum confinement with strongly self-trapped excited (STE) states to give efficient warm orange emission with a photoluminescence quantum yield (PLQY) as high as ≈41.6%. The study accordingly unveils its photoexcited carrier dynamics: rac-3APD-NH4I3 relaxes to STE state with a short lifetime of 10 ps but decays to ground state by emitting photons with a relatively longer lifetime of 560 ps. Additionally, strong quantum confinement effect is conducive to charge transport along the octahedral channels that enables the co-planar single-crystal X-ray detectors to achieve a sensitivity as high as 1556 µC Gyair -1 cm-2. This work demonstrates the first case of photoluminescence mechanism and photophysical dynamics of 1D metal-free perovskite-related semiconductor, as well as the promise for high-performance X-ray detector.

15.
Small ; : e2404438, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39101630

RESUMO

Hematite (α-Fe2O3) has become a research hotspot in the field of photoelectrochemical water splitting (PEC-WS), but the low photogenerated carrier separation efficiency limits further application. The electronic structure regulation, such as element doping and organic functional groups with different electrical properties, is applied to alleviate the problems of poor electrical conductivity, interface defects, and band mismatch. Herein, α-Fe2O3 photoanodes are modified to regulate their electric structures and improve photogenerated carrier transport by the bimetallic metal-organic frameworks (MOFs), which are constructed with Fe/Ni and terephthalate (BDC) with 2-substitution of different organic functional groups (─H, ─Br, ─NO2 and ─NH2). The α-Fe2O3 photoanode loaded with FeNi-NH2BDC MOF catalyst exhibits the optimal photocurrent density (2 mA cm-2) at 1.23 VRHE, which is 2.33 times that of the pure α-Fe2O3 photoanode. The detailed PEC analyses demonstrate that the bimetallic synergistic effect between Fe and Ni can improve the conductivity and inhibit the photogenerated carrier recombination of α-Fe2O3 photoanodes. The ─NH2 group as an electron-donor group can effectively regulate the electron distribution and band structure of α-Fe2O3 photoanodes to prolong the lifetime of photogenerated holes, which facilitates photogenerated carrier transport and further enhances the PEC-WS performance of α-Fe2O3 photoanode.

16.
Plant Biotechnol J ; 22(8): 2333-2347, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38600703

RESUMO

Sterols have long been associated with diverse fields, such as cancer treatment, drug development, and plant growth; however, their underlying mechanisms and functions remain enigmatic. Here, we unveil a critical role played by a GmNF-YC9-mediated CCAAT-box transcription complex in modulating the steroid metabolism pathway within soybeans. Specifically, this complex directly activates squalene monooxygenase (GmSQE1), which is a rate-limiting enzyme in steroid synthesis. Our findings demonstrate that overexpression of either GmNF-YC9 or GmSQE1 significantly enhances soybean stress tolerance, while the inhibition of SQE weakens this tolerance. Field experiments conducted over two seasons further reveal increased yields per plant in both GmNF-YC9 and GmSQE1 overexpressing plants under drought stress conditions. This enhanced stress tolerance is attributed to the reduction of abiotic stress-induced cell oxidative damage. Transcriptome and metabolome analyses shed light on the upregulation of multiple sterol compounds, including fucosterol and soyasaponin II, in GmNF-YC9 and GmSQE1 overexpressing soybean plants under stress conditions. Intriguingly, the application of soybean steroids, including fucosterol and soyasaponin II, significantly improves drought tolerance in soybean, wheat, foxtail millet, and maize. These findings underscore the pivotal role of soybean steroids in countering oxidative stress in plants and offer a new research strategy for enhancing crop stress tolerance and quality from gene regulation to chemical intervention.


Assuntos
Glycine max , Estresse Fisiológico , Glycine max/genética , Glycine max/fisiologia , Glycine max/metabolismo , Estresse Fisiológico/genética , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Plantas Geneticamente Modificadas , Esteroides/metabolismo , Secas , Produtos Agrícolas/genética , Produtos Agrícolas/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética
17.
New Phytol ; 243(6): 2102-2114, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38634162

RESUMO

Mesophyll conductance (gm) is a crucial plant trait that can significantly limit photosynthesis. Measurement of photosynthetic C18O16O discrimination (Δ18O) has proved to be the only viable means of resolving gm in both C3 and C4 plants. However, the currently available methods to exploit Δ18O for gm estimation are error prone due to their inadequacy in constraining the degree of oxygen isotope exchange (θ) during mesophyll CO2 hydration. Here, we capitalized on experimental manipulation of leaf water isotopic dynamics to establish a novel, nonsteady state, regression-based approach for simultaneous determination of gm and θ from online Δ18O measurements. We demonstrated the methodological and theoretical robustness of this new Δ18O-gm estimation approach and showed through measurements on several C3 and C4 species that this approach can serve as a benchmark method against which to identify previously-unrecognized biases of the existing Δ18O-gm methods. Our results highlight the unique value of this nonsteady state-based approach for contributing to ongoing efforts toward quantitative understanding of mesophyll conductance for crop yield improvement and carbon cycle modeling.


Assuntos
Células do Mesofilo , Isótopos de Oxigênio , Fotossíntese , Folhas de Planta , Água , Células do Mesofilo/metabolismo , Células do Mesofilo/fisiologia , Fotossíntese/fisiologia , Água/metabolismo , Folhas de Planta/fisiologia , Folhas de Planta/metabolismo , Análise de Regressão , Dióxido de Carbono/metabolismo
18.
New Phytol ; 242(3): 975-987, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38439696

RESUMO

Stable oxygen isotope ratio of tree-ring α-cellulose (δ18Ocel) yields valuable information on many aspects of tree-climate interactions. However, our current understanding of the mechanistic controls on δ18Ocel is incomplete, with a knowledge gap existent regarding the fractionation effect characterizing carbonyl-water oxygen exchange during sucrose translocation from leaf to phloem. To address this insufficiency, we set up an experimental system integrating a vapor 18O-labeling feature to manipulate leaf-level isotopic signatures in tree saplings enclosed within whole-canopy gas-exchange cuvettes. We applied this experimental system to three different tree species to determine their respective relationships between 18O enrichment of sucrose in leaf lamina (Δ18Ol_suc) and petiole phloem (Δ18Ophl_suc) under environmentally/physiologically stable conditions. Based on the determined Δ18Ophl_suc-Δ18Ol_suc relationships, we estimated that on average, at least 25% of the oxygen atoms in sucrose undergo isotopic exchange with water along the leaf-to-phloem translocation path and that the biochemical fractionation factor accounting for such exchange is c. 34‰, markedly higher than the conventionally assumed value of 27‰. Our study represents a significant step toward quantitative elucidation of the oxygen isotope dynamics during sucrose translocation in trees. This has important implications with respect to improving the δ18Ocel model and its related applications in paleoclimatic and ecophysiological contexts.


Assuntos
Oxigênio , Árvores , Oxigênio/análise , Sacarose , Água/análise , Floema , Isótopos de Oxigênio/análise , Folhas de Planta/química , Isótopos de Carbono/análise
19.
Cardiovasc Diabetol ; 23(1): 177, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38783270

RESUMO

BACKGROUND: Numerous meta-analyses have explored the association between the triglyceride-glucose (TyG) index and diverse health outcomes, yet the comprehensive assessment of the scope, validity, and quality of this evidence remains incomplete. Our aim was to systematically review and synthesise existing meta-analyses of TyG index and health outcomes and to assess the quality of the evidence. METHODS: A thorough search of PubMed, EMBASE, and Web of Science databases was conducted from their inception through to 8 April 2024. We assessed the quality of reviews using A Measurement Tool to Assess Systematic Reviews (AMSTAR) and the certainty of the evidence using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) system. This study was registered with PROSPERO (CRD: 42024518587). RESULTS: Overall, a total of 95 associations from 29 meta-analyses were included, investigating associations between TyG index and 30 health outcomes. Of these, 83 (87.4%) associations were statistically significant (P < 0.05) according to the random effects model. Based on the AMSTAR tool, 16 (55.2%) meta-analyses were high quality and none was low quality. The certainty of the evidence, assessed by the GRADE framework, showed that 6 (6.3%) associations were supported by moderate-quality evidence. When compared with the lowest category of the TyG index, the risk of contrast-induced nephropathy (CIN) [relative risk (RR) = 2.25, 95%CI 1.82, 2.77], the risk of stroke in patients with diabetes mellitus (RR = 1.26, 95%CI 1.18, 1.33) or with acute coronary syndrome disease (RR = 1.56, 95%CI 1.06, 2.28), the prognosis of coronary artery disease (CAD)-non-fatal MI (RR = 2.02, 95%CI 1.32, 3.10), and the severity of CAD including coronary artery stenosis (RR = 3.49, 95%CI 1.71, 7.12) and multi-vessel CAD (RR = 2.33, 95%CI 1.59, 3.42) increased with high TyG index. CONCLUSION: We found that the TyG index was positively associated with many diseases including the risk of CIN and stroke, the prognosis of CAD, and the severity of CAD which were supported by moderate-quality evidence. TyG index might be useful to identify people at high-risk for developing these diseases.


Assuntos
Biomarcadores , Glicemia , Estudos Observacionais como Assunto , Triglicerídeos , Feminino , Humanos , Masculino , Biomarcadores/sangue , Glicemia/metabolismo , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Metanálise como Assunto , Valor Preditivo dos Testes , Prognóstico , Medição de Risco , Fatores de Risco , Revisões Sistemáticas como Assunto , Triglicerídeos/sangue
20.
Microb Pathog ; 194: 106795, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39019122

RESUMO

Feline coronavirus (FCoV) infection is a leading cause of death in cats. In this study, we produced FCoV-I virus-like particles (VLPs) containing E, M, N, and S proteins using a baculovirus expression system and mixed VLPs with the adjuvants MF59 and CpG 55.2 to prepare an VLP/MF59/CpG vaccine. After immunization of mice with the vaccine, IgG specific antibodies titers against S and N proteins increased to 1:12,800, and IFN-γ+ and IL-4+ splenocytes were significantly increased. Following immunization of FCoV-negative cats, the S protein antibodies in immunized cats (5/5) increased significantly, with a peak of 1:12,800. Notably, after booster vaccination in FCoV-positive cats, a significant reduction in viral load was observed in the feces of partial cats (4/5), and the FCoV-I negative conversion was found in two immunized cats (2/5). Therefore, the VLP/MF59/CpG vaccine is a promising candidate vaccine to prevent the FCoV infection.


Assuntos
Adjuvantes Imunológicos , Anticorpos Antivirais , Coronavirus Felino , Imunoglobulina G , Vacinas de Partículas Semelhantes a Vírus , Carga Viral , Animais , Gatos , Vacinas de Partículas Semelhantes a Vírus/imunologia , Vacinas de Partículas Semelhantes a Vírus/administração & dosagem , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Camundongos , Coronavirus Felino/imunologia , Imunoglobulina G/sangue , Adjuvantes Imunológicos/administração & dosagem , Vacinas Virais/imunologia , Vacinas Virais/administração & dosagem , Interleucina-4/metabolismo , Interferon gama/metabolismo , Camundongos Endogâmicos BALB C , Fezes/virologia , Adjuvantes de Vacinas , Polissorbatos/administração & dosagem , Feminino , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/veterinária , Imunogenicidade da Vacina , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/genética , Baço/imunologia , Doenças do Gato/prevenção & controle , Doenças do Gato/imunologia , Doenças do Gato/virologia , Baculoviridae/genética , Vacinação , Imunização Secundária , Esqualeno
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