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1.
Chem Commun (Camb) ; 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39282707

RESUMEN

A highly crystalline and robust Zr-hydroxamate metal-organic framework (MOF) was prepared from a pyrazine-based ligand, featuring abundant N,N' chelating sites. High-degree Pd(II) metalation of the MOF was achieved through straightforward postsynthetic modification, with detailed coordination chemistry elucidated spectroscopically. The Pd-functionalized MOF was then studied as a heterogeneous Suzuki-Miyaura catalyst, through combined experimental/computational methods.

2.
Proc Natl Acad Sci U S A ; 121(37): e2405560121, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39231206

RESUMEN

Collective cell migration is crucial in various physiological processes, including wound healing, morphogenesis, and cancer metastasis. Adherens Junctions (AJs) play a pivotal role in regulating cell cohesion and migration dynamics during tissue remodeling. While the role and origin of the junctional mechanical tension at AJs have been extensively studied, the influence of the actin cortex structure and dynamics on junction plasticity remains incompletely understood. Moreover, the mechanisms underlying stress dissipation at junctions are not well elucidated. Here, we found that the ligand-independent phosphorylation of epithelial growth factor receptor (EGFR) downstream of de novo E-cadherin adhesion orchestrates a feedback loop, governing intercellular viscosity via the Rac pathway regulating actin dynamics. Our findings highlight how the E-cadherin-dependent EGFR activity controls the migration mode of collective cell movements independently of intercellular tension. This modulation of effective viscosity coordinates cellular movements within the expanding monolayer, inducing a transition from swirling to laminar flow patterns while maintaining a constant migration front speed. Additionally, we propose a vertex model with adjustable junctional viscosity, capable of replicating all observed cellular flow phenotypes experimentally.


Asunto(s)
Cadherinas , Movimiento Celular , Receptores ErbB , Fosforilación , Movimiento Celular/fisiología , Cadherinas/metabolismo , Receptores ErbB/metabolismo , Viscosidad , Humanos , Animales , Uniones Adherentes/metabolismo , Perros
3.
Ying Yong Sheng Tai Xue Bao ; 35(7): 1959-1967, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39233426

RESUMEN

The dynamics of soil arthropod communities in annual monoculture grasslands is still unclear, which restricts the understanding of the degradation mechanism of cultivated grasslands. We cultivated two annual gramineae species, Lolium multiflorum and Avena sativa, separately in Hongyuan County, located on the eastern edge of the Qinghai-Tibet Plateau, in April 2019. We investigated soil arthropods, plant communities and soil properties in the cultivated grasslands and natural grassland in the late September every year from 2019 to 2022. The results showed that: 1) The taxonomic composition of soil arthropod communities differed significantly among three grasslands and sampling years. 2) There was no significant difference in the density, taxonomic richness, Shannon index and evenness index of soil arthropod communities among three grasslands. 3) The density of soil arthropod communities significantly fluctuated across years in three grasslands, and the taxonomic richness and Shannon index decreased significantly in the L. multiflorum and A. sativa grasslands, with the evenness index declining significantly only in the fourth year. The Shannon index fluctuated significantly and the evenness index varied little in natural grassland. 4) The above- and below-ground biomass, the contents of soil total P, total K and available N were the main factors influencing the taxonomic composition, density and diversity indices of soil arthropod communities. The results suggested that the cultivation of annual gramineae grasslands have significant effects on taxonomic composition, but not on density and diversity of soil arthropod communities, and those variables change significantly across different years.


Asunto(s)
Artrópodos , Pradera , Suelo , Animales , Artrópodos/clasificación , Artrópodos/crecimiento & desarrollo , Suelo/química , China , Biodiversidad , Dinámica Poblacional , Lolium/crecimiento & desarrollo , Lolium/clasificación , Poaceae/crecimiento & desarrollo , Poaceae/clasificación , Avena/crecimiento & desarrollo , Avena/clasificación , Altitud
4.
Neuroscience ; 559: 181-187, 2024 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-39245313

RESUMEN

OBJECTIVES: The purpose of this study was to investigate the association between cognitive impairments and traumatic upper limb injuries of the acute phase. MATERIAL AND METHODS: A cross-sectional observational study was conducted with three groups: a nerve-injury group, a without nerve injury group, and a control group (uninjured participants). Demographic characteristics (e.g. age, sex, body mass index, and education) and traumatic characteristics (duration since injury, injury side, pain, light touch sensation, hand motor function) were recorded. Short-term memory and executive functions were assessed using Rey Auditory and Verbal Learning Test (RAVLT) and Stroop Color and Word Test (SCWT, including SIECT and SIECN), respectively. RESULTS: The study comprised 43 participants in the nerve-injury group, 30 participants in the group without nerve injury, and 104 participants in the control group. Generalized linear model was applied to explore the difference of cognitive functions among three groups with impactors. Significantly poorer performance on the RAVLT was observed in the nerve-injury group compared to the other two groups, and lower score of SIECT in nerve-injury group was lower compared to the control group. However, there was no significant difference of SIECN among three groups. In addition, traumatic characteristics did not significantly impact RAVLT and SIECT (p > 0.05) in all injured participants. CONCLUSION: Traumatic nerve injury to the upper limb appears to be associated with both short-term memory and executive function impairment, whereas musculoskeletal injuries without nerve damage showed no cognitive impairment. Therefore, it is important to monitor cognitive function following upper limb nerve injuries.

5.
Dalton Trans ; 53(35): 14692-14700, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39157994

RESUMEN

Spin crossover (SCO) has long been a hot topic in the field of molecular magnetism owing to its unique bistability character. Rational control of thermal hysteresis and transition temperature (T1/2) is crucial for their practical applications, which rely on precise manipulation of the substituents of SCO coordinating ligands and molecular packing interactions. In this study, we designed two different bridging ligands (2-FDPB: 4,4'-(2-fluoro-1,4-phenylene)dipyridine; 2,3-FDPB: 4,4'-(2,3-difluoro-1,4-phenylene)dipyridine) featuring one and two fluoro substitution on the central benzene ring and applied a Schiff base-like equatorial tetradentate ligand {diethyl(E,E)-2,2'-[4,5-difluoro-1,2-phenyl-bis(iminomethylidyne)]bis(3-oxobutanoate)-(2-)-N,N',O3,O3'} (H2L) to coordinate with the FeII ion. Two FeII-coordination chain polymers [FeII(L)(2,3-FDPB)]·0.25CH2Cl2 (1) and [FeII(L)(2-FDPB)]·0.5CH3OH (2) were obtained. 1 crystallizes in the monoclinic P21/n space group with only one FeII center, while 2 crystallizes in the triclinic P1̄ space group with two independent FeII centers. Unlike the identical 2D layer stacking in 1, 2 exhibited alternating stacking of the extending 2D layers and meshed chains. Magnetic measurements revealed the typical thermally induced spin crossover behavior (SCO): 1 exhibited a 41 K-wide thermal hysteresis with transition temperatures of T1/2↑ = 245 K and T1/2↓ = 204 K, while 2 showed a higher transition temperature (T1/2 = 330 K) with no thermal hysteresis. Magneto-structural correlation studies suggest that the electron-withdrawing effect present in the fluoro substituents does not have a significant impact on the SCO behaviors. Despite the fluoro substituents having a similar atomic radius of hydrogen atoms, variations in the number of these substituents can alter the crystallization behavior of these complexes, which in turn affects the solvents, molecular stacking patterns, and intermolecular interactions, ultimately influencing the SCO behaviors.

6.
BMC Psychol ; 12(1): 384, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38982552

RESUMEN

BACKGROUND: This theoretical model has been drawn on principles of social exchange theory to scrutinize the connection between organizational virtuousness and job performance with the mediating role of Organizational citizenship behavior and moderating role of workplace ostracism. A survey was conducted in Pakistan, gathering data from 486 employees working for various private and commercial banks. METHOD: Soft and hard questionnaires were distributed to the participants, with social media platforms used for the soft questionnaires and meetings with employees for the hard questionnaires. A 7-point Likert scale was employed in data collection, and measures for the variables were adapted from reliable and valid sources. A demographic analysis was performed to summarize the sample collected from participants. The demographics results were analyzed using SPSS, while the measurement model and path analysis were conducted using Structural Equational Modeling with Smart PLS-4. RESULTS: The study's findings showed a significant and positive relationship between organizational virtuousness and job performance, with organizational citizenship behavior serving as a mediator. Additionally, a negative moderation of workplace ostracism was observed in the mediation of organizational citizenship behavior toward the relationship between organizational virtuousness and job performance. CONCLUSION: The study's results contribute to the implementation of social exchange theory and related concepts in the banking sector of Pakistan, providing practical guidance for implementing virtuous practices within organizations and discouraging ostracism in banks to enhance overall performance. The study suggests that policies regarding the implementation of virtuous practices in organizations can be established, and workplace ostracism can be avoided by providing a platform for social gatherings and training employees. Managers should adopt appropriate leadership styles and relevant communication patterns to impact the organizational climate which can also help reduce the influence of ostracism in the organization. Additionally, a complaint cell should be established with complete confidentiality to reduce ostracism.


Asunto(s)
Cultura Organizacional , Rendimiento Laboral , Humanos , Adulto , Femenino , Pakistán , Masculino , Lugar de Trabajo/psicología , Lugar de Trabajo/organización & administración , Encuestas y Cuestionarios , Conducta Social , Persona de Mediana Edad , Análisis de Clases Latentes , Adulto Joven
7.
Phys Rev E ; 109(5-1): 054406, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38907394

RESUMEN

Cell adhesion proteins typically form stable clusters that anchor the cell membrane to its environment. Several works have suggested that cell membrane protein clusters can emerge from a local feedback between the membrane curvature and the density of proteins. Here, we investigate the effect of such a curvature-sensing mechanism in the context of cell adhesion proteins. We show how clustering emerges in an intermediate range of adhesion and curvature-sensing strengths. We identify key differences with the tilt-induced gradient sensing mechanism we previously proposed (Lin et al., arXiv:2307.03670).


Asunto(s)
Adhesión Celular , Membrana Celular , Membrana Celular/metabolismo , Modelos Biológicos , Moléculas de Adhesión Celular/metabolismo , Proteínas de la Membrana/metabolismo
8.
BMC Genomics ; 25(1): 572, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38844832

RESUMEN

KNOXs, a type of homeobox genes that encode atypical homeobox proteins, play an essential role in the regulation of growth and development, hormonal response, and abiotic stress in plants. However, the KNOX gene family has not been explored in sweet potato. In this study, through sequence alignment, genomic structure analysis, and phylogenetic characterization, 17, 12 and 11 KNOXs in sweet potato (I. batatas, 2n = 6x = 90) and its two diploid relatives I. trifida (2n = 2x = 30) and I. triloba (2n = 2x = 30) were identified. The protein physicochemical properties, chromosome localization, phylogenetic relationships, gene structure, protein interaction network, cis-elements of promoters, tissue-specific expression and expression patterns under hormone treatment and abiotic stresses of these 40 KNOX genes were systematically studied. IbKNOX4, -5, and - 6 were highly expressed in the leaves of the high-yield varieties Longshu9 and Xushu18. IbKNOX3 and IbKNOX8 in Class I were upregulated in initial storage roots compared to fibrous roots. IbKNOXs in Class M were specifically expressed in the stem tip and hardly expressed in other tissues. Moreover, IbKNOX2 and - 6, and their homologous genes were induced by PEG/mannitol and NaCl treatments. The results showed that KNOXs were involved in regulating growth and development, hormone crosstalk and abiotic stress responses between sweet potato and its two diploid relatives. This study provides a comparison of these KNOX genes in sweet potato and its two diploid relatives and a theoretical basis for functional studies.


Asunto(s)
Diploidia , Regulación de la Expresión Génica de las Plantas , Ipomoea batatas , Familia de Multigenes , Filogenia , Proteínas de Plantas , Estrés Fisiológico , Ipomoea batatas/genética , Ipomoea batatas/crecimiento & desarrollo , Ipomoea batatas/metabolismo , Estrés Fisiológico/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Genoma de Planta , Perfilación de la Expresión Génica , Regiones Promotoras Genéticas
9.
Food Chem ; 451: 139507, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38696940

RESUMEN

In the domain of infant nutrition, optimizing the absorption of crucial nutrients such as vitamin D3 (VD3) is paramount. This study harnessed dynamic-high-pressure microfluidization (DHPM) on soybean protein isolate (SPI) to engineer SPI-VD3 nanoparticles for fortifying yogurt. Characterized by notable binding affinity (Ka = 0.166 × 105 L·mol-1) at 80 MPa and significant surface hydrophobicity (H0 = 3494), these nanoparticles demonstrated promising attributes through molecular simulations. During simulated infant digestion, the 80 MPa DHPM-treated nanoparticles showcased an impressive 74.4% VD3 bioaccessibility, delineating the pivotal roles of hydrophobicity, bioaccessibility, and micellization dynamics. Noteworthy was their traversal through the gastrointestinal tract, illuminating bile salts' crucial function in facilitating VD3 re-encapsulation, thereby mitigating crystallization and augmenting absorption. Moreover, DHPM treatment imparted enhancements in nanoparticle integrity and hydrophobic properties, consequently amplifying VD3 bioavailability. This investigation underscores the potential of SPI-VD3 nanoparticles in bolstering VD3 absorption, thereby furnishing invaluable insights for tailored infant nutrition formulations.


Asunto(s)
Disponibilidad Biológica , Colecalciferol , Digestión , Interacciones Hidrofóbicas e Hidrofílicas , Proteínas de Soja , Proteínas de Soja/química , Proteínas de Soja/metabolismo , Humanos , Colecalciferol/química , Colecalciferol/metabolismo , Lactante , Modelos Biológicos , Nanopartículas/química , Nanopartículas/metabolismo
11.
Phys Rev Lett ; 132(18): 188402, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38759206

RESUMEN

Cell adhesion receptors are transmembrane proteins that bind cells to their environment. These proteins typically cluster into disk-shaped or linear structures. Here, we show that such clustering patterns spontaneously emerge when the receptor senses the membrane deformation gradient, for example, by reaching a lower-energy conformation when the membrane is tilted relative to the underlying binding substrate. Increasing the strength of the membrane gradient-sensing mechanism first yields isolated disk-shaped clusters and then long linear structures. Our theory is coherent with experimental estimates of the parameters, suggesting that a tilt-induced clustering mechanism is relevant in the context of cell adhesion.


Asunto(s)
Membrana Celular , Membrana Celular/metabolismo , Modelos Biológicos , Adhesión Celular/fisiología , Separación de Fases , Complejo GPIb-IX de Glicoproteína Plaquetaria
12.
Inorg Chem ; 63(22): 10414-10422, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38772007

RESUMEN

Developing metal-organic materials (MOMs) with chemical robustness is a prerequisite to exploring their intriguing properties and applications. As part of a continuing effort to construct robust MOMs featuring chelated building units, here we introduce a "bent" thiophene-2,5-dihydroxamate ligand with multiple intrinsic conformations when it is used as a chelating linkage. This approach should further diversify the coordination chemistry in hydroxamate-based MOM structures without compromising the stability. In combination with Group 13 metals Ga/In to ensure homoleptic metal vertices, we report the successful crystallization of four MOMs with diverse structures and dimensionalities: SUM-81 as a 0D metal-organic polyhedron (MOP), SUM-82 as a 2D MOF with an fes topology, SUM-83 and SUM-84 as distinct 1D coordination polymers with shapes mimic stairs and mesh tubes, respectively. As these structures indeed contain the aforementioned different ligand conformations and combinations thereof, these results expand our understanding of the coordination chemistry of hydroxamates. To demonstrate the potential applicability of hydroxamate-chelated robust MOMs, the permanently porous SUM-81 MOP was successfully incorporated in a series of mixed matrix membranes for CO2/N2 separation, showing impressive performances.

13.
Eur J Neurosci ; 60(1): 3629-3642, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38697919

RESUMEN

Microglia are endogenous immune cells in the brain, and their pyroptosis and phenotype dichotomy are proved to play roles in neurodegenerative diseases. We investigated whether and how hypoxia affected pyroptosis and phenotype polarization in mouse microglia. Primary mouse microglia and BV2 microglia were exposed to hypoxia. Pyroptosis and M1/M2 phenotype were assessed by measuring gasdermin D truncation and M1/M2 surface marker expression. Mechanisms including purinergic ionotropic receptor (P2XR), peroxisome proliferator-activated receptor coactivator-1α (PGC-1α) and NOD-like receptor protein 3 (NLRP3) inflammasome were investigated. We reported hypoxia (90% N2, 5% O2 and 5% CO2) induced pyroptosis and promoted M1 phenotype polarization in primary mouse microglia and BV2 microglia, and the effect appeared after 6 h exposure. Although hypoxia (90% N2, 5% O2 and 5% CO2, 6 h) had no effect on P2X1R and P2X7R expression, it increased P2X4R expression and decreased PGC-1α expression. Interestingly, blockade of P2X4R or P2X7R abolished hypoxia-modulated PGC-1α expression, pyroptosis and M1 polarization. PGC-1α overexpression or overactivation alleviated hypoxia-induced pyroptosis and M1 polarization, while PGC-1α knockdown or deactivation promoted pyroptosis and M1 polarization under normoxic situation. Further, hypoxia induced NLRP3 expression and activated caspase-1 and induced the phosphorylation of NF-κB and reduced the phosphorylation of STAT3/6. NLRP3 inhibitor and caspase-1 inhibitor abolished hypoxia-induced pyroptosis, while NF-κB inhibitor and STAT phosphorylation inducer ameliorated hypoxia-induced M1 polarization. In addition, NF-κB activator and STAT3/6 inhibitor caused microglia M1 polarization under normoxic situation. We concluded in cultured mouse microglia, hypoxia may induce pyroptosis via P2XR/PGC-1α/NLRP3/caspase-1 pathway and trigger M1 polarization through P2XR/PGC-1α/NF-κB/STAT3/6 pathway.


Asunto(s)
Microglía , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma , Piroptosis , Transducción de Señal , Animales , Piroptosis/fisiología , Microglía/metabolismo , Ratones , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo , Transducción de Señal/fisiología , Diferenciación Celular/fisiología , Diferenciación Celular/efectos de los fármacos , Ratones Endogámicos C57BL , Hipoxia de la Célula/fisiología , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Células Cultivadas , Inflamasomas/metabolismo , Fenotipo , Hipoxia/metabolismo
14.
J Mol Cell Biol ; 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38578631

RESUMEN

The recognition of cytosolic nucleic acid triggers the DNA/RNA sensor-IRF3 axis-mediated production of type I interferons (IFNs), which are essential for antiviral immune responses. However, the inappropriate activation of these signaling pathways is implicated in autoimmune conditions. Here, we report that indomethacin, a widely used nonsteroidal anti-inflammatory drug, inhibits nucleic acid-triggered IFN production. We found that both DNA- and RNA-stimulated IFN expression can be effectively blocked by indomethacin. Interestingly, indomethacin also prohibits the nuclear translocation of IRF3 following cytosolic nucleic acid recognition. Importantly, in cell lines and a mouse model of Aicardi-Goutières syndrome, indomethacin administration blunts self-DNA-induced autoimmune responses. Thus, our study reveals a previously unknown function of indomethacin and provides a potential treatment for cytosolic nucleic acid-stimulated autoimmunity.

15.
Injury ; 55(3): 111367, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38301489

RESUMEN

DESIGN: Clinimetric evaluation study. INTRODUCTION: The Chinese Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire has necessitated the development of a revised version to the specific needs of individuals with upper extremity injuries with the progress of times and lifestyle changes. PURPOSE OF THE STUDY: This research aimed to evaluate the reliability and validity of Modified Chinese Disability of Arm, Shoulder and Hand (MC-DASH) questionnaire in individuals with upper extremity injuries. METHODS: One hundred and one individuals with upper extremity injuries (UEI) were recruited. The function of upper extremity was measured using the electronic version of MC-DASH, and compared against the Chinese Disability of Arm, Shoulder and Hand. The MC-DASH was reassessed within three days in all individuals. We investigated the internal consistency, test-retest reliability, content validity, criterion validity, and construct validity of MC-DASH. RESULTS: The internal consistency was deemed sufficient, as indicated by a Cronbach's alpha of 0.986 and an intraclass correlation coefficient of 0.957. Moreover, the mean total scores of MC-DASH on the first-test and retest were 37.86 and 38.19, respectively (ICC: 0.957, 95 %CI: 0.937-0.971, p < 0.001). Furthermore, the MC-DASH version exhibited satisfactory content validity evidenced by its strong correlation (R= 0.903, p < 0.001) with the Chinese DASH. Three major influencing factors were identified from 37 items. The cumulative variance contribution rate of the MC-DASH questionnaire was 75.76 %, confirming its construct validity. CONCLUSION: The Modified Chinese Disability of Arm, Shoulder and Hand questionnaire has been shown to be a valid, reliable, and practical tool for use in patients with upper extremity injuries.


Asunto(s)
Traumatismos del Brazo , Hombro , Humanos , Brazo , Reproducibilidad de los Resultados , Evaluación de la Discapacidad , Extremidad Superior , Mano , Traumatismos del Brazo/diagnóstico , Encuestas y Cuestionarios , Ceguera , China/epidemiología
16.
Food Funct ; 15(6): 2895-2905, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38404190

RESUMEN

Anxiety- and depression-like behaviors are commonly observed clinical features of depression and many other mental disorders. Recent evidence has revealed the crucial role of the microbiota-gut-brain axis in the bidirectional communication between the gastrointestinal tract and the central nervous system. Supplementation with psychobiotics may provide a novel approach for the adjunctive treatment of mental disorders by regulating the intestinal microecology. We isolated and identified a novel probiotic, Lactiplantibacillus plantarum D-9 (D-9), from traditional Chinese fermented foods in our previous work, which exhibited a high yield of gamma-aminobutyric acid (GABA). Herein, it was proved that the oral administration of D-9 could alleviate the depression- and anxiety-like behaviors of Chronic Unpredicted Mild Stress (CUMS) mice, and show non-toxicity or side-effects in the mice. Physiological and biochemical analyses demonstrated that D-9 regulated tryptophan metabolism, the HPA-axis and inflammation in CUMS mice. Moreover, D-9 modulated the structure and composition of the gut microbiota, leading to an increase in the relative abundance of Ligilactobacillus murinus and Lactobacillus johnsonii, and a decrease in the levels of Kineothrix alysoides and Helicobacter bilis compared to those in CUMS mice. Our work demonstrates that D-9 alleviated anxiety- and depression-like disorders in CUMS mice by modulating tryptophan metabolism and the gut microbiota. These findings provide an innovative strategy for the intervention and treatment of depressive disorders.


Asunto(s)
Microbioma Gastrointestinal , Fármacos Neuroprotectores , Humanos , Animales , Ratones , Triptófano , Depresión/tratamiento farmacológico , Ansiedad/tratamiento farmacológico
17.
Inorg Chem ; 63(4): 1720-1724, 2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38214245

RESUMEN

Starting from labile hydroxamic acid ligands that are strong chelators, here, we implemented a sacrificial modulating strategy to prepare a series of scandium carboxylate metal-organic frameworks. Overcoming conventional syntheses that use excessive carboxylate modulators, the present strategy greatly reduces the organics required and produces large single crystals of several Sc-MOFs for X-ray crystallography.

18.
Nat Struct Mol Biol ; 31(1): 42-53, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38177668

RESUMEN

DNA cytosine methylation plays a vital role in repressing retrotransposons, and such derepression is linked with developmental failure, tumorigenesis and aging. DNA methylation patterns are formed by precisely regulated actions of DNA methylation writers (DNA methyltransferases) and erasers (TET, ten-eleven translocation dioxygenases). However, the mechanisms underlying target-specific oxidation of 5mC by TET dioxygenases remain largely unexplored. Here we show that a large low-complexity domain (LCD), located in the catalytic part of Tet enzymes, negatively regulates the dioxygenase activity. Recombinant Tet3 lacking LCD is shown to be hyperactive in converting 5mC into oxidized species in vitro. Endogenous expression of the hyperactive Tet3 mutant in mouse oocytes results in genome-wide 5mC oxidation. Notably, the occurrence of aberrant 5mC oxidation correlates with a consequent loss of the repressive histone mark H3K9me3 at ERVK retrotransposons. The erosion of both 5mC and H3K9me3 causes ERVK derepression along with upregulation of their neighboring genes, potentially leading to the impairment of oocyte development. These findings suggest that Tet dioxygenases use an intrinsic auto-regulatory mechanism to tightly regulate their enzymatic activity, thus achieving spatiotemporal specificity of methylome reprogramming, and highlight the importance of methylome integrity for development.


Asunto(s)
5-Metilcitosina , Dioxigenasas , Animales , Ratones , 5-Metilcitosina/metabolismo , Dioxigenasas/genética , Dioxigenasas/metabolismo , Retroelementos/genética , Metilación de ADN , Oocitos/metabolismo , Desmetilación
19.
J Environ Manage ; 352: 119976, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38198835

RESUMEN

Developing scientific and effective carbon emissions reduction policies relies heavily on precise carbon emission trend prediction. The existing complex spatiotemporal correlation and diverse range of influencing factors associated with multi-regional carbon emissions pose significant challenges to accurately modeling these trends. Under this constraint, this study is inspired by graph learning to establish a hybrid dynamic and static graph-based regional carbon emission network framework, which introduces a novel research standpoint for investigating short-term carbon emissions prediction (CEP). Specifically, a parallel framework of attribute-augmented dynamic multi-modal graph convolutional neural networks (ADMGCN) and temporal convolutional networks with adaptive fusion multi-scale receptive fields (AFMRFTCN) is proposed. The proposed model is evaluated against nineteen state-of-the-art models using daily carbon emission data from 30 regions in China, demonstrating its effectiveness in accurately predicting the trends of multi-regional carbon emissions. Conclusions are drawn as follows: First, especially in regions with marked periodicity, compared with the best baseline model, the mean absolute percentage error (MAPE) of our model is reduced by 20.19%. Second, incorporating graph convolutional neural networks (GCNs) with dynamic and static graphs is advantageous in extracting the spatial features of China's carbon emission network, which are influenced by geographical, economic, and industrial factors. Third, the parallel ADMGCN-AFMRFTCNs framework effectively captures the influence of external information on carbon emissions while mitigating the issue of low prediction accuracy resulting from univariate information. Fourth, the analysis reveals significant differences in the short-term (30-day) growth rate of carbon emissions among different regions. For example, Henan exhibits the highest growth rate (37.38%), while Guizhou has the lowest growth rate (-7.46%). It is valuable for policymakers and stakeholders seeking to identify regions with distinct emission patterns and prioritize mitigation efforts accordingly.


Asunto(s)
Carbono , Industrias , China , Geografía , Aprendizaje , Dióxido de Carbono
20.
Plant Physiol ; 194(2): 787-804, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-37815230

RESUMEN

Root development influences plant responses to environmental conditions, and well-developed rooting enhances plant survival under abiotic stress. However, the molecular and genetic mechanisms underlying root development and abiotic stress tolerance in plants remain unclear. In this study, we identified the MYB transcription factor-encoding gene IbMYB73 by cDNA-amplified fragment length polymorphism and RNA-seq analyses. IbMYB73 expression was greatly suppressed under abiotic stress in the roots of the salt-tolerant sweet potato (Ipomoea batatas) line ND98, and its promoter activity in roots was significantly reduced by abscisic acid (ABA), NaCl, and mannitol treatments. Overexpression of IbMYB73 significantly inhibited adventitious root growth and abiotic stress tolerance, whereas IbMYB73-RNAi plants displayed the opposite pattern. IbMYB73 influenced the transcription of genes involved in the ABA pathway. Furthermore, IbMYB73 formed homodimers and activated the transcription of ABA-responsive protein IbGER5 by binding to an MYB binding sites I motif in its promoter. IbGER5 overexpression significantly inhibited adventitious root growth and abiotic stress tolerance concomitantly with a reduction in ABA content, while IbGER5-RNAi plants showed the opposite effect. Collectively, our results demonstrated that the IbMYB73-IbGER5 module regulates ABA-dependent adventitious root growth and abiotic stress tolerance in sweet potato, which provides candidate genes for the development of elite crop varieties with well-developed root-mediated abiotic stress tolerance.


Asunto(s)
Ácido Abscísico , Ipomoea batatas , Ácido Abscísico/farmacología , Ácido Abscísico/metabolismo , Ipomoea batatas/genética , Ipomoea batatas/metabolismo , Plantas Modificadas Genéticamente/metabolismo , Análisis del Polimorfismo de Longitud de Fragmentos Amplificados , Estrés Fisiológico/fisiología , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
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