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1.
Org Lett ; 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-32037843

RESUMO

Two bis-BN phenanthrenes have been synthesized. Their photophysical properties are different from those of the reported mono-BN phenanthrenes. Moreover, the stepwise bromination of bis-BN phenanthrene 8 gave a series of brominated bis-BN phenanthrenes, with all of the mono-, di-, tri-, and tetrabrominated bis-BN phenanthrenes being successfully isolated and characterized. In addition, preliminary results showed that mono- and dibrominated species can be further functionalized by cross-coupling reactions.

3.
PLoS One ; 14(2): e0210892, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30753186

RESUMO

The content and size of stone cell clusters affects the quality of pear fruit, and monolignol polymerization and deposition in the cell walls constitute a required step for stone cell formation. Laccase (LAC) is the key enzyme responsible for the polymerization of monolignols. However, there are no reports on the LAC family in pear (Pyrus bretschneideri), and the identity of the members responsible for lignin synthesis has not been clarified. Here, 41 LACs were identified in the whole genome of pear. All Pyrus bretschneideri LACs (PbLACs) were distributed on 13 chromosomes and divided into four phylogenetic groups (I-IV). In addition, 16 segmental duplication events were found, implying that segmental duplication was a primary reason for the expansion of the PbLAC family. LACs from the genomes of three Rosaceae species (Prunus mummer, Prunus persica, and Fragaria vesca) were also identified, and an interspecies collinearity analysis was performed. The phylogenetic analysis, sequence alignments and spatiotemporal expression pattern analysis suggested that PbLAC1, 5, 6, 29, 36 and 38 were likely associated with lignin synthesis and stone cell formation in fruit. The two target genes of Pyr-miR1890 (a microRNA identified from pear fruit that is associated with lignin and stone cell accumulation), PbLAC1 and PbLAC14, were selected for genetic transformation. Interfamily transfer of PbLAC1 into Arabidopsis resulted in a significant increase (approximately 17%) in the lignin content and thicker cell walls in interfascicular fibre and xylem cells, which demonstrated that PbLAC1 is involved in lignin biosynthesis and cell wall development. However, the lignin content and cell wall thickness were not changed significantly in the PbLAC14-overexpressing transgenic Arabidopsis plants. This study revealed the function of PbLAC1 in lignin synthesis and provides important insights into the characteristics and evolution of the PbLAC family.


Assuntos
Frutas , Genoma de Planta , Lacase , Lignina , Proteínas de Plantas , Pyrus , Frutas/enzimologia , Frutas/genética , Estudo de Associação Genômica Ampla , Lacase/biossíntese , Lacase/genética , Lignina/biossíntese , Lignina/genética , Proteínas de Plantas/biossíntese , Proteínas de Plantas/genética , Pyrus/enzimologia , Pyrus/genética
4.
In Vitro Cell Dev Biol Anim ; 55(2): 104-112, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30617572

RESUMO

Human menstrual blood-derived mesenchymal stem cells (MenSCs) hold great promise for regenerative medicine. Here, H2O2-associated damage in H9c2 cells was employed as an in vitro ischemia-reperfusion model, and the transwell system was used to explore the beneficial effects of MenSCs on the H2O2-induced damage of myocardial H9c2 cells. H2O2 treatment resulted in decreased viability and migration rate, with increased apoptosis levels in cells. By contrast, upon co-culture with MenSCs, H9c2 cell viability and migration were increased, whereas the apoptotic rate decreased. Additionally, western blot and qRT-PCR showed that MenSCs mediated the anti-apoptotic role by downregulating the pro-apoptotic genes Bax and caspase-3, while upregulating the anti-apoptotic effector Bcl-2. Furthermore, co-culture with MenSCs resulted in elevated expression of N-cadherin after H2O2 treatment. These findings indicate that MenSCs protect H9c2 cells against H2O2-associated programmed cell death and would help develop therapeutic tools for cardiomyocyte apoptosis associated with oxidative stress.


Assuntos
Apoptose/efeitos dos fármacos , Células Sanguíneas/citologia , Citoproteção/efeitos dos fármacos , Peróxido de Hidrogênio/toxicidade , Menstruação/sangue , Células-Tronco Mesenquimais/metabolismo , Animais , Apoptose/genética , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Separação Celular , Sobrevivência Celular/efeitos dos fármacos , Técnicas de Cocultura , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Células-Tronco Mesenquimais/efeitos dos fármacos , Ratos
5.
Front Genet ; 9: 136, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29713336

RESUMO

Stone cells content and size are the key factors determining the internal quality of the pear fruit. Synthesis of lignin and thickening of secondary cell wall are the keys to the development of stone cells. The polymerization of monolignols and secondary cell wall formation requires the participation of dirigent proteins (DIRs). In recent years, DIR family have been studied in higher plants, but lack of comprehensive study in the pear DIR (PbDIR) family. This study focuses on the identification and analysis of PbDIR family for the first time. We identified 35 PbDIRs from the pear genome, 89% of which are intronless genes. Phylogenetic tree and chromosome localization analysis showed that 35 PbDIRs were divided into four subfamilies (DIR-a, -b/d, -e, and -g) and irregularly distributed among 10 chromosomes. In addition, we identified 29, 26, and 14 DIRs from the other three Rosids (peach, Mei, and grape), respectively. Interspecies microsynteny analysis revealed the collinear gene pairs between pear and peach are the most. Temporal expression analysis showed that the expression changes of seven PbDIRs (DIR-a subfamily: PbDIR4 and PbDIR5; DIR-b/d subfamily: PbDIR11; DIR-g subfamily: PbDIR19; DIR-e subfamily: PbDIR23, 25 and 26) in fruits were consistent with the changes of fruit lignin and stone cells contents. In addition, the subfamily of PbDIRs in fruits showed significant responses after treatment with ABA, SA, and MeJA. According to the protein tertiary structure, key amino acid residues and expression patterns analysis found that PbDIR4 might be involved in the metabolism of lignin and related to stone cells contents in pear fruits. In this study, we systematically analyzed the structure, evolution, function and expression of PbDIR family, which not only confirmed the characteristics of PbDIR family, but also laid the foundation for revealing the role of DIR in pear stone cell development and lignin polymerization.

6.
Org Lett ; 20(10): 2806-2810, 2018 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-29727188

RESUMO

A series of bis-BN ullazine derivatives, including the parent species, were synthesized in a small number of steps from commercially available materials. X-ray crystallographic analysis revealed that bis-BN ullazines have rigid and planar frameworks. Most of the bis-BN ullazines are stable toward air and moisture. In addition, the absorption and emission bands of these ullazines are blue-shifted, compared to those of their carbonaceous ullazine analogs.

7.
Chem Commun (Camb) ; 54(59): 8178-8181, 2018 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-29789849

RESUMO

A series of aryl-fused bis-BN dihydropyrenes were synthesized via amino-directed borylation reaction. The aryl-fused bis-BN dihydropyrenes showed blue emission, and their physical properties could be finely tuned through varying the fused aryl rings. In particular, their response towards fluoride anions was greatly dependent on the nature of the fused aryl rings.

8.
Biol Open ; 6(11): 1602-1613, 2017 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-29141952

RESUMO

The content of stone cells has significant effects on the flavour and quality of pear fruit. Previous research suggested that lignin deposition is closely related to stone cell formation. In the lignin biosynthetic pathway, cinnamoyl-CoA reductase (CCR) and cinnamyl alcohol dehydrogenase (CAD), dehydrogenase/reductase family members, catalyse the last two steps in monolignol synthesis. However, there is little knowledge of the characteristics of the CCR and CAD families in pear and their involvement in lignin synthesis of stone cells. In this study, 31 CCRs and 26 CADs were identified in the pear genome. Phylogenetic trees for CCRs and CADs were constructed; key amino acid residues were analysed, and three-dimensional structures were predicted. Using quantitative real-time polymerase chain reaction (qRT-PCR), PbCAD2, PbCCR1, -2 and -3 were identified as participating in lignin synthesis of stone cells in pear fruit. Subcellular localization analysis showed that the expressed proteins (PbCAD2, PbCCR1, -2 and -3) are found in the cytoplasm or at the cell membrane. These results reveal the evolutionary features of the CCR and CAD families in pear as well as the genes responsible for regulation of lignin synthesis and stone cell development in pear fruit.

9.
PLoS One ; 12(10): e0187114, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29088238

RESUMO

Stone cell content is thought to be one of the key determinants for fruit quality in pears. However, the molecular mechanism of stone cell development remains poorly understood. In this study, we found that the stone cell clusters (SCCs) distribution and area in 'Dangshan Su' (with abundant stone cells) were higher as compared to 'Lianglizaosu' (low stone cell content bud sport of 'Dangshan Su') based on the histochemical staining, and the correlations of lignin content with stone cell content and SCC area was significant. The fruits of 'Dangshan Su' and 'Lianglizaosu' at three different developmental stages (23 and 55 days after flowering and mature) were sampled for comparative transcriptome analysis to explore the metabolic pathways associated with stone cell development. A total of 42444 unigenes were obtained from two varieties, among which 7203 differentially expressed genes (DEGs) were identified by comparison of the six transcriptomes. Specifically, many DEGs associated with lignin biosynthesis were identified, including coumaroylquinate 3-monooxygenase (C3H), shikimate O-hydroxycinnamoyltransferase (HCT), ferulate 5-hydroxylase (F5H), cinnamyl alcohol dehydrogenase (CAD) and peroxidase (POD), as well as genes related to carbon metabolism, such as sorbitol dehydrogenase-like (SDH-like) and ATP-dependent 6-phosphofructokinase (ATP-PFK). At the peak of the stone cell content (55 days after flowering), the expression level of these genes in 'Dangshan Su' was significantly increased compared with 'Lianglizaosu', indicating that these genes were closely related to stone cell development. We validated the transcriptional levels of 33 DEGs using quantitative real-time polymerase chain reaction (qRT-PCR) analysis. The results were consistent with the transcriptome analysis, indicating the reliability of transcriptome data. In addition, subcellular localization analysis of three DEGs in lignin synthesis (PbC3H, PbF5H and PbPOD) revealed that these proteins are mainly distributed in the cell membrane and cytoplasm. These results provide new insights into the molecular mechanism of stone cell formation.


Assuntos
Frutas/citologia , Pyrus/genética , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Estudos de Associação Genética , Lignina/metabolismo , Redes e Vias Metabólicas/genética , Pyrus/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de DNA
10.
Biomed Res Int ; 2017: 2794040, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28497043

RESUMO

The high-throughput sequencing of pear "Dangshan Su" × "Yali" (whose fruits lignin and stone cell content are high and quality is poor) and pear "Dangshan Su" × "Wonhwang" (whose fruits with low content of lignin and stone cell and the quality are better ) found that the expressions of these two miRNAs (pyr-1809 and pyr-novel-miR-144-3p) were significantly different; their corresponding target genes encode two kinds of laccase (Pbr018935.1 and Pbr003857.1). qRT-PCR results showed that these two enzymes are involved in the formation of lignin and stone cells and the existence of these two miRNAs has a negative effect on them. It was concluded that the effect of pollination on the development of stone cells may affect the synthesis of lignin, through the regulation of laccase controlled by miRNAs, and ultimately affect the formation of stone cell and fruit quality.


Assuntos
Regulação da Expressão Gênica de Plantas/fisiologia , MicroRNAs/biossíntese , Polinização/fisiologia , Pyrus/metabolismo , RNA de Plantas/biossíntese , Lacase/biossíntese , Lacase/genética , MicroRNAs/genética , Proteínas de Plantas/biossíntese , Proteínas de Plantas/genética , Pyrus/genética , RNA de Plantas/genética
11.
Environ Pollut ; 170: 169-76, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22819953

RESUMO

Cities can be modelled as giant organisms, with their own metabolic processes, and can therefore be studied using the same tools used for biological metabolic systems. The complicated distribution of compartments within these systems and the functional relationships among them define the system's network structure. Taking Beijing as an example, we divided the city's internal system into metabolic compartments, then used ecological network analysis to calculate a comprehensive utility matrix for the flows between compartments within Beijing's metabolic system from 1998 to 2007 and to identify the corresponding functional relationships among the system's compartments. Our results show how ecological network analysis, utility analysis, and relationship analysis can be used to discover the implied ecological relationships within a metabolic system, thereby providing insights into the system's internal metabolic processes. Such analyses provide scientific support for urban ecological management.


Assuntos
Cidades/estatística & dados numéricos , Monitoramento Ambiental/métodos , Poluição Ambiental/estatística & dados numéricos , China , Ecossistema , Poluição Ambiental/análise , Modelos Teóricos , Resíduos/estatística & dados numéricos
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