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1.
Int J Mol Sci ; 25(2)2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38255862

RESUMO

Ethylene is one crucial phytohormone modulating plants' organ development and ripening process, especially in fruits, but its action modes and discrepancies in non-climacteric grape and climacteric peach in these processes remain elusive. This work is focused on the action mode divergences of ethylene during the modulation of the organ development and ripening process in climacteric/non-climacteric plants. We characterized the key enzyme genes in the ethylene synthesis pathway, VvACO1 and PpACO1, and uncovered that their sequence structures are highly conserved, although their promoters exhibit important divergences in the numbers and types of the cis-elements responsive to hormones, implying various responses to hormone signals. Subsequently, we found the two have similar expression modes in vegetative organ development but inverse patterns in reproductive ones, especially in fruits. Then, VvACO1 and PpACO1 were further validated in promoting fruit ripening functions through their transient over-expression/RNAi-expression in tomatoes, of which the former possesses a weaker role than the latter in the fruit ripening process. Our findings illuminated the divergence in the action patterns and function traits of the key VvACO1/PpACO1 genes in the tissue development of climacteric/non-climacteric plants, and they have implications for further gaining insight into the interaction mechanism of ethylene signaling during the modulation of the organ development and ripening process in climacteric/non-climacteric plants.


Assuntos
Climatério , Prunus persica , Vitis , Prunus persica/genética , Vitis/genética , Menopausa , Etilenos
2.
Int J Mol Sci ; 24(22)2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-38003470

RESUMO

Exogenous GA is widely used to efficiently induce grape seedless berry development for significantly improving berry quality. Recently, we found that VvmiR166s are important regulators of response to GA in grapes, but its roles in GA-induced seedless grape berry development remain elusive. Here, the precise sequences of VvmiR166s and their targets VvREV, VvHB15 and VvHOX32 were determined in grape cv. 'Rosario Bianco', and the cleavage interactions of VvmiR166s-VvHB15/VvHOX32/VvREV modules and the variations in their cleavage roles were confirmed in grape berries. Exogenous GA treatment significantly induced a change in their expression correlations from positive to negative between VvmiR166s and their target genes at the seeds during the stone-hardening stages (32 DAF-46 DAF) in grape berries, indicating exogenous GA change action modes of VvmiR166s on their targets in this process, in which exogenous GA mainly enhanced the negative regulatory roles of VvmiR166s on VvHB15 among all three VvmiR166s-target pairs. The transient OE-VvmiR166a-h/OE-VvHB15 in tobacco confirmed that out of the VvmiR166 family, VvmiR166h/a/b might be the main factors in modulating lignin synthesis through inhibiting VvHB15, of which VvmiR166h-VvHB15-NtPAL4/NtCCR1/NtCCR2/NtCCoAMT5/NtCOMT1 and VvmiR166a/b-VvHB15-NtCAD1 are the potential key regulatory modules in lignin synthesis. Together with the GA-induced expression modes of VvmiR166s-VvHB15 and genes related to lignin synthesis in grape berries, we revealed that GA might repress lignin synthesis mainly by repressing VvCAD1/VvCCR2/VvPAL2/VvPAL3/Vv4CL/VvLac7 levels via mediating VvmiR166s-VvHB15 modules in GA-induced grape seedless berries. Our findings present a novel insight into the roles of VvmiR66s that are responsive to GA in repressing the lignin synthesis of grape seedless berries, with different lignin-synthesis-enzyme-dependent action pathways in diverse plants, which have important implications for the molecular breeding of high-quality seedless grape berries.


Assuntos
Frutas , Vitis , Frutas/metabolismo , Vitis/metabolismo , Lignina/metabolismo , Giberelinas/farmacologia , Giberelinas/metabolismo , Regulação da Expressão Gênica de Plantas
3.
World J Stem Cells ; 14(10): 744-755, 2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36337155

RESUMO

Osteoarthritis (OA) is considered to be a highly heterogeneous disease with progressive cartilage loss, subchondral bone remodeling, and low-grade inflammation. It is one of the world's leading causes of disability. Most conventional clinical treatments for OA are palliative drugs, which cannot fundamentally cure this disease. The stromal vascular fraction (SVF) from adipose tissues is a heterogeneous cell population. According to previous studies, it contains a large number of mesenchymal stem cells, which have been used to treat OA with good therapeutic results. This safe, simple, and effective therapy is expected to be applied and promoted in the future. In this paper, the detailed pathogenesis, diagnosis, and current clinical treatments for OA are introduced. Then, clinical studies and the therapeutic mechanism of SVF for the treatment of OA are summarized.

4.
Neuroimage Clin ; 36: 103173, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36081257

RESUMO

OBJECTIVE: To determine whether tumor shear stiffness, as measured by magnetic resonance elastography, corresponds with intratumoral consistency and histotype. MATERIALS AND METHODS: A total of 88 patients with 89 meningiomas (grade 1, 74 typical [13 fibroblastic, 61 non-fibroblastic]; grade 2, 12 atypical; grade 3, 3 anaplastic) were prospectively studied, each undergoing preoperative MRE in conjunction with T1-, T2- and diffusion-weighted imaging. Contrast-enhanced T1-weighted sequences were also obtained. Tumor consistency was evaluated as heterogeneous or homogenous, and graded on a 5-point scale intraoperatively. MRE-determined shear stiffness was associated with tumor consistency by surgeon's evaluation and whole-slide histologic analyses. RESULTS: Mean tumor stiffness overall was 3.81+/-1.74 kPa (range, 1.57-12.60 kPa), correlating well with intraoperative scoring (r = 0.748; p = 0.001). MRE performed well as a gauge of tumor consistency (AUC = 0.879, 95 % CI: 0.792-0.938) and heterogeneity (AUC = 0.773, 95 % CI: 0.618-0.813), significantly surpassing conventional MR techniques (DeLong test, all p < 0.001 after Bonferroni adjustment). Shear stiffness was independently correlated with both fibrous content (partial correlation coefficient = 0.752; p < 0.001) and tumor cellularity (partial correlation coefficient = 0.547; p < 0.001). MRE outperformed other imaging techniques in distinguishing fibroblastic meningiomas from other histotypes (AUC = 0.835 vs 0.513 âˆ¼ 0.634; all p < 0.05), but showed limited ability to differentiate atypical or anaplastic meningiomas from typical meningiomas (AUC = 0.723 vs 0.616 âˆ¼ 0.775; all p > 0.05). Small (<2.5 cm, n = 6) and intraventricular (n = 2) tumors displayed inconsistencies between MRE and surgeon's evaluation. CONCLUSIONS: The results of this prospective study provide substantial evidence that preoperative evaluation of meningiomas with MRE can reliably characterize tumor stiffness and spatial heterogeneity to aid neurosurgical planning.


Assuntos
Técnicas de Imagem por Elasticidade , Neoplasias Meníngeas , Meningioma , Humanos , Técnicas de Imagem por Elasticidade/métodos , Estudos Prospectivos , Imageamento por Ressonância Magnética/métodos , Meningioma/diagnóstico por imagem , Meningioma/cirurgia , Meningioma/patologia , Neoplasias Meníngeas/diagnóstico por imagem , Neoplasias Meníngeas/cirurgia , Neoplasias Meníngeas/patologia
5.
Front Plant Sci ; 12: 692036, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34691090

RESUMO

Mediator is a conserved multiprotein complex important for transcription by RNA polymerase II (Pol II). Arabidopsis Mediator subunit MED18 regulates flowering, hormone signaling and plant immunity. Here we report that Arabidopsis MED18 interacted with NUCLEAR RNA POLYMERASE D2a (NRPD2a), the second largest subunit of the nuclear Pol IV and V, which function in RNA-directed DNA methylation and epigenetic regulation of gene expression. Mutants for both MED18 and NRPD2a were compromised in resistance to necrotrophic fungal pathogen Botrytis cinerea. Mutants for NRPD1a, the largest subunit of Pol IV, were also compromised in resistance to Botrytis, supporting a critical role of Pol IV and V in plant defense against Botrytis. Increased Botrytis susceptibility of both the med18 and nrpd2a mutants were associated with reduced accumulation of reactive oxygen species, which are known to promote resistance to Botrytis. Both the basal and pathogen-induced levels of salicylic acid and jasmonic acid were also significantly altered in the med18 and nrpd2a mutants. Transcriptome profiling found that MED18 and NRPD2a affected both unique and overlapping sets of genes in a broad spectrum of biological processes and pathways that influence plant-pathogen interaction. The genes altered in expression in the med18 and nrpd2a mutants include disease resistance proteins, salicylic acid and jasmonic acid signaling and responses, which are known to affect resistance to necrotrophic pathogens. The novel interaction between subunits of Mediator and plant-specific RNA polymerases provides a new mechanism for epigenetic regulation of resistance and expression of defense-related genes in plant immunity.

6.
Sensors (Basel) ; 19(7)2019 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-30970645

RESUMO

The Hemispherical Resonator Gyro (HRG) is a solid-state and widely used vibrating gyroscope, especially in the field of deep space exploration. The flat-electrode HRG is a new promising type of gyroscope with simpler structure that is easier to be fabricated. In this paper, to cover the shortage of a classical generalized Coriolis Vibration Gyroscope model whose parameters are hard to obtain, the model of flat-electrode HRG is established by the equivalent mechanical model, the motion equations of unideal hemispherical shell resonator are deduced, and the calculation results of parameters in the equations are verified to be reliable and believable by comparing with finite element simulation and the reported experimental data. In order to more truthfully reveal the input and output characteristics of HRG, the excitation and detection models with assemble errors and parameters are established based on the model of flat-electrode capacitor, and they convert both the input and output forms of the HRG model to voltage changes across the electrodes rather than changes in force and capacitance. An identification method of assemble errors and parameters is proposed to evaluate and improve the HRG manufacturing technology and adjust the performance of HRG. The average gap could be identified with the average capacitance of all excitation and detection capacitors; fitting the approximate static capacitor model could identify the inclination angle and direction angle. With the obtained model, a firm and tight connection between the real HRG system and theoretical model is established, which makes it possible to build a fully functional simulation model to study the control and detection methods of standing wave on hemispherical shell resonator.

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