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1.
J Integr Plant Biol ; 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38629459

RESUMO

Most mechanistic details of chronologically ordered regulation of leaf senescence are unknown. Regulatory networks centered on AtWRKY53 are crucial for orchestrating and integrating various senescence-related signals. Notably, AtWRKY53 binds to its own promoter and represses transcription of AtWRKY53, but the biological significance and mechanism underlying this self-repression remain unclear. In this study, we identified the VQ motif-containing protein AtVQ25 as a cooperator of AtWRKY53. The expression level of AtVQ25 peaked at mature stage and was specifically repressed after the onset of leaf senescence. AtVQ25-overexpressing plants and atvq25 mutants displayed precocious and delayed leaf senescence, respectively. Importantly, we identified AtWRKY53 as an interacting partner of AtVQ25. We determined that interaction between AtVQ25 and AtWRKY53 prevented AtWRKY53 from binding to W-box elements on the AtWRKY53 promoter and thus counteracted the self-repression of AtWRKY53. In addition, our RNA-sequencing data revealed that the AtVQ25-AtWRKY53 module is related to the salicylic acid (SA) pathway. Precocious leaf senescence and SA-induced leaf senescence in AtVQ25-overexpressing lines were inhibited by an SA pathway mutant, atsid2, and NahG transgenic plants; AtVQ25-overexpressing/atwrky53 plants were also insensitive to SA-induced leaf senescence. Collectively, we demonstrated that AtVQ25 directly attenuates the self-repression of AtWRKY53 during the onset of leaf senescence, which is substantially helpful for understanding the timing of leaf senescence onset modulated by AtWRKY53.

2.
J Exp Bot ; 75(8): 2351-2371, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38205848

RESUMO

Plant senescence, as a highly integrated developmental stage, involves functional degeneration and nutrient redistribution. NAM/ATAF1/CUC (NAC) transcription factors orchestrate various senescence-related signals and mediate the fine-tuning underlying plant senescence. Previous data revealed that knockout of either NtNAC028 or NtNAC080 leads to delayed leaf senescence in tobacco (Nicotiana tabacum), which implies that NtNAC028 and NtNAC080 play respective roles in the regulation of leaf senescence, although they share 91.87% identity with each other. However, the mechanism underlying NtNAC028- and NtNAC080-regulated leaf senescence remains obscure. Here, we determined that NtNAC028 and NtNAC080 activate a putative jasmonic acid (JA) biosynthetic gene, NtLOX3, and enhance the JA level in vivo. We found that NtNAC028 and NtNAC080 interact with each other and themselves through their NA-terminal region. Remarkably, only the dimerization between NtNAC028 and NtNAC080 stimulated the transcriptional activation activity, but not the DNA binding activity of this heterodimer on NtLOX3. Metabolome analysis indicated that overexpression of either NtNAC028 or NtNAC080 augments both biosynthesis and degradation of nicotine in the senescent stages. Thus, we conclude that NtNAC028 cooperates with NtNAC080 and forms a heterodimer to enhance NtLOX3 expression and JA biosynthesis to trigger the onset of leaf senescence and impact secondary metabolism in tobacco.


Assuntos
Ciclopentanos , Nicotiana , Oxilipinas , Fatores de Transcrição , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Nicotiana/genética , Senescência Vegetal , Folhas de Planta/metabolismo , Regulação da Expressão Gênica de Plantas
3.
Nat Prod Res ; 38(6): 1036-1043, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37221665

RESUMO

Aralianudaside A, a triterpene saponin with an unusual skeleton of pentacyclic triterpenoid, along with a new triterpene glycoside and six known compounds were obtained from the buds of Aralia elata. Their structures were determined through extensive spectral analysis, including HRESIMS, IR, 1D and 2D NMR, glycolysis and GC. All compounds were evaluated for anti-airway inflammatory activity in lipopolysaccharides (LPS)-induced airway epithelial cells (16HBE), compounds 1, 3, 5, 7 and 8 significantly decreased the expression of pro-inflammatory cytokines IL-1ß and IL-4.


Assuntos
Aralia , Saponinas , Triterpenos , Aralia/química , Saponinas/química , Triterpenos/farmacologia , Triterpenos/química , Lipopolissacarídeos/farmacologia , Esqueleto/química
4.
Food Res Int ; 174(Pt 1): 113656, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37986490

RESUMO

This study examined the bacterial community dynamics and their relationship with volatile compounds in Xinjiang smoked horsemeat sausage during fermentation. We employed single-molecule real-time sequencing (SMRT) to identify the bacterial composition, while headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS) was utilized to detect volatile compounds in the sausage. The findings indicated that Staphylococcus xylosus, Lactococcus garvieae, Latilactobacillus sakei, Lactococcus lactis, and Weissella hellenica were the predominant species during the fermentation. Moreover, we identified 56 volatile substances in the smoked horsemeat sausages, including alcohols, esters, ketones, acids, aldehydes, terpenes, and phenols. Notably, the correlation analysis demonstrated positive associations between the major bacteria and the primary volatile compounds, with notable connections observed for Staphylococcus xylosus, Lactococcus garvieae and Weissella hellenica. These research findings provide a foundation for future endeavors aimed at enhancing the flavor quality of smoked horsemeat sausage.


Assuntos
Bactérias , Fumaça , Fermentação
5.
Int J Mol Sci ; 24(18)2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37762142

RESUMO

Leaf senescence is an important factor affecting the functional transition from nutrient assimilation to nutrient remobilization in crops. The senescence of wheat leaves is of great significance for its yield and quality. In the leaf senescence process, transcriptional regulation is a committed step in integrating various senescence-related signals. Although the plant-specific transcriptional regulation factor valine-glutamine (VQ) gene family is known to participate in different physiological processes, its role in leaf senescence is poorly understood. We isolated TaVQ25-A and studied its function in leaf senescence regulation. TaVQ25-A was mainly expressed in the roots and leaves of wheat. The TaVQ25-A-GFP fusion protein was localized in the nuclei and cytoplasm of wheat protoplasts. A delayed senescence phenotype was observed after dark and abscisic acid (ABA) treatment in TaVQ25-A-silenced wheat plants. Conversely, overexpression of TaVQ25-A accelerated leaf senescence and led to hypersensitivity in ABA-induced leaf senescence in Arabidopsis. A WRKY type transcription factor, TaWRKY133, which is tightly related to the ABA pathway and affects the expression of some ABA-related genes, was found to interact with TaVQ25-A both in vitro and in vivo. Results of this study indicate that TaVQ25-A is a positive regulator of ABA-related leaf senescence and can be used as a candidate gene for wheat molecular breeding.


Assuntos
Arabidopsis , Triticum , Triticum/genética , Ácido Abscísico , Senescência Vegetal , Nutrientes , Glutamina , Arabidopsis/genética
6.
Plant J ; 114(3): 570-590, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36815286

RESUMO

Leaf senescence involves massive multidimensional alterations, such as nutrient redistribution, and is closely related to crop yield and quality. No apical meristem, Arabidopsis transcription activation factor, and Cup-shaped cotyledon (NAC)-type transcription factors integrate various signals and modulate an enormous number of target genes to ensure the appropriate progression of leaf senescence. However, few leaf senescence-related NACs have been functionally characterized in wheat. Based on our previous RNA-sequencing (RNA-seq) data, we focused on a NAC family member, TaNAC69-B, which is increasingly expressed during leaf senescence in wheat. Overexpression of TaNAC69-B led to precocious leaf senescence in wheat and Arabidopsis, and affected several agricultural traits in transgenic wheat. Moreover, impaired expression of TaNAC69-B by virus-induced gene silencing retarded the leaf senescence in wheat. By RNA-seq and quantitative real-time polymerase chain reaction analysis, we confirmed that some abscisic acid (ABA) biosynthesis genes, including AAO3 and its ortholog in wheat, TraesCS2B02G270600 (TaAO3-B), were elevated by the overexpression of TaNAC69-B. Consistently, we observed more severe ABA-induced leaf senescence in TaNAC69-B-OE wheat and Arabidopsis plants. Furthermore, we determined that TaNAC69-B bound to the NAC binding site core (CGT) on the promoter regions of AAO3 and TaAO3-B. Moreover, we confirmed elevated ABA levels in TaNAC69-B-OE wheat lines. Although TaNAC69-B shares 39.83% identity (amino acid) with AtNAP, TaNAC69-B did not completely restore the delayed leaf senescence in the atnap mutant. Collectively, our results revealed a positive feedback loop, consisting of TaNAC69-B, ABA biosynthesis and leaf senescence, that is essential for the regulation of leaf senescence in wheat.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Triticum/metabolismo , Senescência Vegetal , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Folhas de Planta/genética , Folhas de Planta/metabolismo , Ácido Abscísico/metabolismo
7.
Clin Exp Rheumatol ; 41(4): 902-909, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36826789

RESUMO

OBJECTIVES: Takayasu's arteritis (TAK) is a progressive autoimmune vasculitis that mainly affects the aorta and its major branches. While recent studies have identified proinflammatory T cells, including Th1 and Th17 cells, as the dominant infiltrates in the arterial adventitia, mechanisms underpinning the maintenance of such vasculogenic T cells remain obscure. METHODS: 75 patients with TAK and 30 age-matched healthy controls were enrolled in this study. CD4 T cells from TAK patients were activated with anti-CD3/CD28 beads to mimic vasculogenic T cells. The survival of T cells was detected by quantifying Annexin-V+7-AAD+ fractions. Expression and activity of AMP-activated protein kinase (AMPK) were determined using phosflow cytometry and immunoblots. Specific inhibitors and shRNA were applied to block the function of AMPK and Notch1, while erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were used to reflect the disease activity of TAK patients. RESULTS: T cells from TAK patients undergo spontaneous differentiation into vasculogenic proinflammatory T cells with prolonged survival capacity. Mechanistic explorations uncover AMPK hyperactivity in such T cells from TAK patients, promoting mitochondrial metabolism and their survival. Such AMPK hyperactivity results from the robust Notch1 activity in TAK T cells. Accordingly, T cell-intrinsic phosphor-AMPK reflects the disease activity in clinical TAK patients. CONCLUSIONS: AMPK hyperactivity is essential for maintaining the vasculogenic proinflammatory T cells in TAK patients, serving as a promising therapeutic target for TAK management.


Assuntos
Arterite de Células Gigantes , Arterite de Takayasu , Humanos , Proteínas Quinases Ativadas por AMP/uso terapêutico , Proteína C-Reativa/metabolismo , Diferenciação Celular , Linfócitos T/imunologia
8.
Org Lett ; 24(43): 7912-7917, 2022 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-36269864

RESUMO

3-(2-(Ethynyl)phenyl)quinazolinones were designed and synthesized as a class of novel and efficient skeletons for phosphorylation/cyclization reactions. Under visible light irradiation, a series of phosphorylated quinolino[2,1-b]quinazolinones (35 examples, up to 87% yield) were first synthesized from 3-(2-(ethynyl)phenyl)quinazolinones and diarylphosphine oxides by using 4CzIPN as a photocatalyst under mild conditions. This reaction was also applicable under sunlight irradiation. Moreover, the reaction efficiency could be significantly improved under continuous-flow conditions.


Assuntos
Luz , Quinazolinonas , Ciclização , Fosforilação
9.
ACS Chem Biol ; 17(2): 395-403, 2022 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-35060718

RESUMO

Members of the Crotonase superfamily, a mechanistically diverse family of proteins that share a conserved quaternary structure, can often catalyze more than one reaction. However, the spectrum of activity for its members has not been well studied. We report on measured crotonase and hydrolase activity for eight structural genomics (SG) proteins from the Crotonase superfamily plus two previously characterized proteins, intended as controls: human enoyl CoA hydratase (ECH) and Anabaena ß-diketone hydrolase. Like most of the 15,000+ SG protein structures deposited in the Protein Data Bank (PDB), the eight SG proteins are of unknown or uncertain biochemical function. The functional characterization of the eight SG proteins is guided by the Structurally Aligned Local Sites of Activity (SALSA), a local-structure-based computational approach to functional annotation. For human ECH, the turnover number for hydrolase activity is threefold higher than that for ECH activity, although the catalytic efficiency is 160-fold higher for ECH. Three SG proteins originally annotated as ECHs were predicted by SALSA to be hydrolases and are observed to have higher catalytic efficiencies for hydrolase activity than for ECH activity, on par with the previously characterized hydrolase. Among the five SG proteins predicted by SALSA to be ECHs, all but one also show some hydrolase activity; all five exhibit lower ECH activity than the human ECH with respect to the crotonyl-CoA substrate. Here, we show examples demonstrating that SALSA can correct functional misannotations even within enzyme families that display promiscuous activity.


Assuntos
Enoil-CoA Hidratase , Hidrolases , Catálise , Bases de Dados de Proteínas , Enoil-CoA Hidratase/química , Enoil-CoA Hidratase/metabolismo , Genômica , Humanos , Hidrolases/química
10.
J Asian Nat Prod Res ; 24(8): 738-745, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34581235

RESUMO

Two new triucallane triterpenoids, polystanin F (1) and polystanin G (2), along with eight known compounds (3-10) were isolated from the fruits of Aphanamixis polystachya. Their structures were established on the basis of extensive spectroscopic analysis. Moreover, eight compounds were evaluated for their in vitro cytotoxicity against three cancer cell lines (liver cancer RT112, colon cancer HCT-116 and breast cancer M231) using the MTT method. Compound 7 showed significant cytotoxic activity against HCT-116 with IC50 1.27 µM.


Assuntos
Limoninas , Meliaceae , Triterpenos , Frutas/química , Limoninas/química , Meliaceae/química , Estrutura Molecular , Triterpenos/análise , Triterpenos/farmacologia
11.
Front Plant Sci ; 12: 717233, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34539711

RESUMO

Leaf senescence is crucial for crop yield and quality. Transcriptional regulation is a key step for integrating various senescence-related signals into the nucleus. However, few regulators of senescence implicating transcriptional events have been functionally characterized in wheat. Based on our RNA-seq data, we identified a WRKY transcription factor, TaWRKY13-A, that predominately expresses at senescent stages. By using the virus-induced gene silencing (VIGS) method, we manifested impaired transcription of TaWRKY13-A leading to a delayed leaf senescence phenotype in wheat. Moreover, the overexpression (OE) of TaWRKY13-A accelerated the onset of leaf senescence under both natural growth condition and darkness in Brachypodium distachyon and Arabidopsis thaliana. Furthermore, by physiological and molecular investigations, we verified that TaWRKY13-A participates in the regulation of leaf senescence via jasmonic acid (JA) pathway. The expression of JA biosynthetic genes, including AtLOX6, was altered in TaWRKY13-A-overexpressing Arabidopsis. We also demonstrated that TaWRKY13-A can interact with the promoter of AtLOX6 and TaLOX6 by using the electrophoretic mobility shift assay (EMSA) and luciferase reporter system. Consistently, we detected a higher JA level in TaWRKY13-A-overexpressing lines than that in Col-0. Moreover, our data suggested that TaWRKY13-A is partially functional conserved with AtWRKY53 in age-dependent leaf senescence. Collectively, this study manifests TaWRKY13-A as a positive regulator of JA-related leaf senescence, which could be a new clue for molecular breeding in wheat.

12.
Front Plant Sci ; 12: 709625, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34421956

RESUMO

Plant height is an important agronomic trait that is closely related to biomass yield and crop production. Despite legumes comprise one of the largest monophyletic families that are second only to grasses in terms of economic and nutritional values, due to an ancient genome duplication event, most legume plants have complex genomes, thus the molecular mechanisms that determine plant height are less known in legumes. Here, we report the identification and characterization of MAIN STEM DWARF1 (MSD1), which is required for the plant height in the model legume Medicago truncatula. Loss of function of MSD1 leads to severely reduced main stem height but normal lateral branch elongation in M. truncatula. Histological analysis revealed that the msd1-1 main stem has shorter internodes with reduced cell size and number compared with the wild type, indicating that MSD1 affects cell elongation and cell proliferation. MSD1 encodes a putative GA 20-oxidase that is expressed at significantly higher levels in the main shoot apex than in the lateral shoot apices, suggesting that MSD1 expression is associated with its effect on the main stem elongation. UPLC-MS/MS analysis showed that GA9 and GA4, two identified products of the GA 20-oxidase, were severely reduced in msd1-1, and the dwarf phenotype of msd1-1 could be rescued by supplementation with gibberellic acid GA3, confirming that MSD1 functions as a biologically active GA 20-oxidase. Moreover, we found that disruption of either MtGA20ox7 or MtGA20ox8, homologs of MSD1, has little effects on the elongation of the main stem, while the msd1-1 mtga20ox7-1 mtga20ox8 triple mutants exhibits a severe short main shoot and lateral branches, as well as reduced leaf size, suggesting that MSD1 and its homologs MtGA20ox7 and MtGA20ox8, redundantly regulate M. truncatula shoot elongation and leaf development. Taken together, our findings demonstrate the molecular mechanism of MSD1-mediated regulation of main stem elongation in M. truncatula and provide insights into understanding the functional diversity of GA 20-oxidases in optimizing plant architecture in legumes.

13.
Angew Chem Int Ed Engl ; 60(31): 17155-17163, 2021 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-34041830

RESUMO

Although Fenton or Fenton-like reactions have been widely used in the environment, biology, life science, and other fields, the sharp decrease in their activity under macroneutral conditions is still a large problem. This study reports a MoS2 cocatalytic heterogeneous Fenton (CoFe2 O4 /MoS2 ) system capable of sustainably degrading organic pollutants, such as phenol, in a macroneutral buffer solution. An acidic microenvironment in the slipping plane of CoFe2 O4 is successfully constructed by chemically bonding with MoS2 . This microenvironment is not affected by the surrounding pH, which ensures the stable circulation of Fe3+ /Fe2+ on the surface of CoFe2 O4 /MoS2 under neutral or even alkaline conditions. Additionally, CoFe2 O4 /MoS2 always exposes "fresh" active sites for the decomposition of H2 O2 and the generation of 1 O2 , effectively inhibiting the production of iron sludge and enhancing the remediation of organic pollutants, even in actual wastewater. This work not only experimentally verifies the existence of an acidic microenvironment on the surface of heterogeneous catalysts for the first time, but also eliminates the pH limitation of the Fenton reaction for pollutant remediation, thereby expanding the applicability of Fenton technology.


Assuntos
Dissulfetos/química , Poluentes Ambientais/química , Compostos Férricos/química , Molibdênio/química , Recuperação e Remediação Ambiental , Concentração de Íons de Hidrogênio
14.
Angew Chem Int Ed Engl ; 60(6): 2903-2908, 2021 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-33098249

RESUMO

It is important to develop self-producing reactive oxygen species (ROSs) systems and maintain the continuous and effective degradation of organic pollutants. Herein, for the first time, a system of ultrasound-treated CoS2-x mixed with Fe2+ is constructed to sustainably release singlet oxygen (1 O2 ) for the effective degradation of various organic pollutants, including dyes, phenols, and antibiotics. Ultrasonic treatment produces defects on the surface of CoS2 which promote the production of ROSs and the circulation of Fe3+ /Fe2+ . With the help of Co4+ /Co3+ exposed on the surface of CoS2-x , the directional conversion of superoxide radical (. O2- ) to 1 O2 is realized. The CoS2-x /Fe2+ system can degrade organic pollutants efficiently for up to 30 days, which is significantly better than the currently recognized CuPx system (<3 days). Therefore, CoS2-x provides a new choice for the long-term remediation of organic pollutants in controlling large area river pollution.


Assuntos
Cobalto/química , Poluentes Químicos da Água/química , Catálise , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/metabolismo , Ferro/química , Oxirredução , Espécies Reativas de Oxigênio/química , Espécies Reativas de Oxigênio/metabolismo , Sonicação , Superóxidos/química , Superóxidos/metabolismo , Poluentes Químicos da Água/metabolismo
15.
PLoS One ; 15(8): e0238243, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32853270

RESUMO

In the North China Plain, coal mining subsided lakes are surface water bodies that form after the conclusion of coal mining. In China, mining subsided lakes are often transformed into artificial wetland parks for ecological restoration. While many studies have focused on evaluating coal mining subsidence lake ecosystem service value and water pollution, little attention has been paid to changes in ecological regimes and ecological spillover effects before and after the reclamation of mining areas. This paper examines the Pan'an Lake artificial wetland in Jiawang District, Xuzhou, as a case study. Changes in the ecological regime of the mining subsidence area before and after land reclamation and corresponding spatial spillover effect on land prices are assessed based on remote sensing, GIS raster calculations and geostatistical methods. The results show that the ecosystem service value and ecological storage capacity changed significantly after the mining subsided lake was transformed into an artificial wetland and the wetland ecosystem has been developing well with significantly positive spillover effects on surrounding land prices. From 2008 to 2017, service functions of the artificial wetland ecosystem of Pan'an Lake increased by 81.95%, and the system's ecological storage capacity increased from RMB 6,754 yuan/hm2 in 2008 to RMB 12,289 yuan/hm2 in 2017. The average impact of the Pan'an Lake artificial wetland on the spillover effects of surrounding residential land prices was measured at RMB 195.18 yuan/m2, and the total spillover value of planned residential land in the study area was measured at RMB 805,422,100 yuan. The present study can serve as a useful guide for evaluating the economic feasibility of land reclamation planning and ecological restoration in mining subsidence areas.


Assuntos
Minas de Carvão/métodos , Conservação dos Recursos Naturais/métodos , China , Ecologia/métodos , Ecossistema , Monitoramento Ambiental/métodos , Lagos , Áreas Alagadas
16.
Spectrochim Acta A Mol Biomol Spectrosc ; 242: 118712, 2020 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-32717524

RESUMO

A new thiophene hydrazide derivative TSB was synthesized and utilized as naked-eye colorimetric sensor for Cu2+ by the color changed from colorless to yellow as well as green fluorescent turn on sensor for Al3+ in DMSO/H2O (1/1, V/V) solution. The dual-functional chemosensor TSB for Cu2+/Al3+ sensing displayed excellent properties of special selectivity, superior sensitivity, outstanding anti-interference performance, instantaneous response, wide pH working range and good reversibility. The detection limits of TSB for Cu2+/Al3+ were determined as low as 46.5 nM and 32.7 nM, respectively. The 1:1 binding mode of TSB with Cu2+/Al3+ was proved by spectrometric titrations, Job's plots, FTIR, 1H NMR and HRMS analysis. Moreover, chemosensor TSB was successfully utilized for detection of Cu2+ and Al3+ in real environmental water and food samples with high reliability, demonstrating its practical applicability.

17.
New Phytol ; 226(5): 1399-1412, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31981419

RESUMO

Organ size is a major agronomic trait that determines grain yield and biomass production in crops. However, the molecular mechanisms controlling organ size, especially in legumes, are poorly understood. Using forward genetic approaches in a Tnt1 insertion mutant population of the model legume Medicago truncatula, we identified SMALL LEAF AND BUSHY1 (SLB1), which is required for the control of organ size and lateral branching. Loss of function of SLB1 led to reduced leaf and flower size but increased lateral branch formation in M. truncatula. SLB1 encodes an F-box protein, an orthologue of Arabidopsis thaliana STERILE APETALA (SAP), that forms part of an SKP1/Cullin/F-box E3 ubiquitin ligase complex. Biochemical and genetic analyses revealed that SLB1 controls M. truncatula organ growth and lateral branching by modulating the stability of BIG SEEDS1 (BS1). Moreover, the overexpression of SLB1 increased seed and leaf size in both M. truncatula and soybean (Glycine max), indicating functional conservation. Our findings revealed a novel mechanism by which SLB1 targets BS1 for degradation to regulate M. truncatula organ size and shoot branching, providing a new genetic tool for increasing seed yield and biomass production in crop and forage legumes.


Assuntos
Medicago truncatula , Flores/metabolismo , Regulação da Expressão Gênica de Plantas , Medicago truncatula/genética , Medicago truncatula/metabolismo , Tamanho do Órgão , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
18.
Front Neuroanat ; 13: 47, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31143102

RESUMO

A unique nucleus, the cerebrospinal fluid (CSF)-contacting nucleus, has recently been recognized in the brain parenchyma. The outstanding feature of this nucleus is that the neural somas are located in the parenchyma, but their processes stretch into the CSF, implying that it may be a key structure bridging the nervous and body fluids-regulating systems and may play a pivotal role in modulating physiological activities. However, the true biological significance of this nucleus needs to be uncovered. The morphology of a nucleus is one of the most important parameters for neuroscience studies. For this reason, a common experimental animal, Sprague-Dawley (SD) rats, was chosen. The position, adjacent structures, neuronal distribution, size, three-dimensional reconstruction, and core coordinates of the CSF-contacting nucleus in SD rats of different weights (90-400 g) were illustrated for the first time. Furthermore, the formulas for calculating the core coordinates of the CSF-contacting nucleus in rats of different weights were revealed. Finally, the possible biological functions uncovered by past research are reviewed in this paper. This study provides an indispensable methodology and a significant reference for researchers interested in this unique nucleus.

19.
Curr Org Synth ; 16(7): 1032-1039, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31984884

RESUMO

AIMS AND OBJECTIVES: 2,2'-Arylmethylene bis(3-hydroxy-5,5-dimethyl-2-cyclohexene-1-one) having four carbonyl functionalities along with their tautomeric keto-enol forms, is an important biologically active compound and important synthetic intermediate in the synthesis of xanthenes. This study was conducted in order to develop a new and concise method of synthesis of 2,2'-arylmethylene bis (3-hydroxy-5,5-dimethyl-2- cyclohexene-1-one) derivatives. MATERIALS AND METHODS: TEAOH (20 mol %) was fond to be as a simple and efficient catalyst for the preparation of 2,2'-arylmethylene bis(3-hydroxy-5,5-dimethyl-2-cyclohexene-1-one) derivatives by the Knoevenagel condensation/Michael addition tandem reactions. RESULTS: A concise and practical method was developed for one-pot synthesis of 2,2'-arylmethylene bis(3- hydroxy-5,5-dimethyl-2-cyclohexene-1-one) derivatives catalyzed by TEAOH at room temperature in various solvents. CONCLUSION: This strategy provides several advantages over the traditional synthetic method, and is applicable to a wide variety of aromatic and heteroaromatic aldehydes at room temperature in various solvents.

20.
Exp Neurol ; 298(Pt A): 112-121, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28890075

RESUMO

Alpha calcium/calmodulin dependent protein kinase II (αCaMKII) is a serine/threonine protein kinase which is expressed abundantly in dorsal striatum and is highly involved in the corticostriatal synaptic plasticity. Nevertheless, it currently remains unclear whether and how αCaMKII plays a in the striatum-related neural disorders. To address the above issue, lentivirus-mediated short hairpin RNA (shRNA) was used to silence the expression of αCaMKII gene in the dorsal striatum of mice. As a consequence of down-regulation of dorsal striatal αCaMKII expression, we observed defective motor skill learning in accelerating rotarod and response learning in water cross maze. Furthermore, impaired corticostriatal basal transmission and long-term potentiation (LTP), which correlated with the deficits in dorsal striatum-related cognition, were also detected in the αCaMKII-shRNA mice. Consistent with the above results, αCaMKII-shRNA mice exhibited a remarkable decline in GluA1-Ser831 and GluA1-Ser845 phosphorylation levels of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR), and a decline in the expression levels of N-methyl-d-aspartic acid receptor (NMDAR) subunits NR1, NR2A and NR2B. Taken together, αCaMKII down-regulation caused dorsal striatum-related cognitive disorders by inhibiting corticostriatal synaptic plasticity, which resulted from dysfunction of AMPARs and NMDARs. Our findings demonstrate for the first time an important role of αCaMKII in striatum-related neural disorders and provide further evidence for the proposition that corticostriatal LTP underlies aspects of dorsal striatum-related cognition.


Assuntos
Proteínas de Transporte/metabolismo , Transtornos Cognitivos/metabolismo , Corpo Estriado/metabolismo , Regulação para Baixo/fisiologia , Sinapses/metabolismo , Animais , Proteínas de Ligação ao Cálcio , Proteínas de Transporte/antagonistas & inibidores , Corpo Estriado/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Potenciais Pós-Sinápticos Excitadores/fisiologia , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Plasticidade Neuronal/efeitos dos fármacos , Plasticidade Neuronal/fisiologia , Técnicas de Cultura de Órgãos , Peptídeos/farmacologia , Sinapses/efeitos dos fármacos
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