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1.
Plant Sci ; 336: 111851, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37648116

RESUMO

As a significant transcription factor family in plants, WRKYs have a crucial role in responding to different adverse environments. They have been repeatedly demonstrated to contribute to drought resistance. However, no systematic exploration of the WRKY family has been reported in the evergreen shrub Ammopiptanthus nanus under drought conditions. Here, we showed that AnWRKY29 expression is strongly induced under drought stress. AnWRKY29 belongs to the group IIe of WRKY gene family. To characterize the function of AnWRKY29, we generated transgenic plants overexpressing this gene in Arabidopsis thaliana. We determined that AnWRKY29 overexpression of mainly improves the drought resistance of transgenic plants to water stress by reducing water loss, preventing electrolyte leakage, and increasing the absorption of inorganic ions. In addition, the AnWRKY29 transgenic plants synthesized more trehalose under water stress. The overexpression of AnWRKY29 also enhanced the antioxidant and osmoregulation capacity of transgenic plants by increasing the activities of catalase, peroxidase and superoxide dismutase, thus increasing the scavenging of reactive oxygen species and propylene glycol synthesis aldehyde oxidase. In summary, our study shows that AnWRKY29 plays an important role in the drought tolerance pathway in plants.

2.
Molecules ; 28(3)2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36770814

RESUMO

Radical reactions are powerful in creating carbon-carbon and carbon-heteroatom bonds. Designing one-pot radical reactions with cascade transformations to assemble the cyclic skeletons with two new functional groups is both synthetically and operationally efficient. Summarized in this paper is the recent development of reactions involving radical addition and cyclization of dienes, diynes, enynes, as well as arene-bridged and arene-terminated compounds for the preparation of difunctionalization cyclic compounds. Reactions carried out with radical initiators, transition metal-catalysis, photoredox, and electrochemical conditions are included.

3.
Molecules ; 27(17)2022 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-36080259

RESUMO

G2-like (GLK) transcription factors contribute significantly and extensively in regulating chloroplast growth and development in plants. This study investigated the genome-wide identification, phylogenetic relationships, conserved motifs, promoter cis-elements, MCScanX, divergence times, and expression profile analysis of PeGLK genes in moso bamboo (Phyllostachys edulis). Overall, 78 putative PeGLKs (PeGLK1-PeGLK78) were identified and divided into 13 distinct subfamilies. Each subfamily contains members displaying similar gene structure and motif composition. By synteny analysis, 42 orthologous pairs and highly conserved microsynteny between regions of GLK genes across moso bamboo and maize were found. Furthermore, an analysis of the divergence times indicated that PeGLK genes had a duplication event around 15 million years ago (MYA) and a divergence happened around 38 MYA between PeGLK and ZmGLK. Tissue-specific expression analysis showed that PeGLK genes presented distinct expression profiles in various tissues, and many members were highly expressed in leaves. Additionally, several PeGLKs were significantly up-regulated under cold stress, osmotic stress, and MeJA and GA treatment, implying that they have a likelihood of affecting abiotic stress and phytohormone responses in plants. The results of this study provide a comprehensive understanding of the moso bamboo GLK gene family, as well as elucidating the potential functional characterization of PeGLK genes.


Assuntos
Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Poaceae/genética , Poaceae/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
4.
Molecules ; 26(1)2020 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-33379397

RESUMO

Popular and readily available alkenes and alkynes are good substrates for the preparation of functionalized molecules through radical and/or ionic addition reactions. Difunctionalization is a topic of current interest due to its high efficiency, substrate versatility, and operational simplicity. Presented in this article are radical addition followed by oxidation and nucleophilic addition reactions for difunctionalization of alkenes or alkynes. The difunctionalization could be accomplished through 1,2-addition (vicinal) and 1,n-addition (distal or remote) if H-atom or group-transfer is involved in the reaction process. A wide range of moieties, such as alkyl (R), perfluoroalkyl (Rf), aryl (Ar), hydroxy (OH), alkoxy (OR), acetatic (O2CR), halogenic (X), amino (NR2), azido (N3), cyano (CN), as well as sulfur- and phosphorous-containing groups can be incorporated through the difunctionalization reactions. Radicals generated from peroxides or single electron transfer (SET) agents, under photoredox or electrochemical reactions are employed for the reactions.


Assuntos
Alcenos/química , Alcinos/química , Radicais Livres/química , Oxirredução , Peróxidos/química
5.
Alzheimers Dement (N Y) ; 5: 441-449, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31517031

RESUMO

INTRODUCTION: This randomized, double-blind trial aimed to test effect of a Chinese herbal medicine, Qinggongshoutao (QGST) pill, on the cognition and progression of amnestic mild cognitive impairment (aMCI). METHODS: Patients with aMCI were randomly assigned to receive QGST, Ginkgo biloba extract, or placebo for 52 weeks. The primary outcome measures were progression to possible or probable Alzheimer's disease (AD) and change in Alzheimer's Disease Assessment Scale-cognitive subscale scores; secondary outcome measures included assessments for cognition and function. RESULTS: Total 350 patients were enrolled, possible or probable AD developed in 10. There were significant differences in the probability of progression to AD in the QGST group (1.15%) compared with placebo group (10%). There was significant difference in Alzheimer's Disease Assessment Scale-cognitive subscale scores in favor of QGST over the placebo group. Secondary outcome measure (Mini-Mental State Examination) also showed benefit in QGST at end point. DISCUSSION: In patients with aMCI, QGST showed lower AD progression rate than placebo at 8.85%, and may have benefit on global cognition.

6.
Funct Plant Biol ; 42(2): 126-135, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32480659

RESUMO

Heterotrimeric G-proteins play an important role in plant signalling pathways. The plant hormone methyl jasmonate (MeJA) can induce stomatal closure in many plant species. The signal cascade in MeJA-induced stomatal closure has been studied previously. However, the function of G proteins in this process has not yet been evaluated. In this study, the stomatal movement induced by MeJA in the wild-type Arabidopsis thaliana (L. Heynh.) (WS), Gα subunit loss-of-function mutant gpa1-1 and gpa1-2 guard cells were measured. Further, the transmembrane ion flux (H+, Ca2+ and K+) and reactive oxygen species (ROS) experiments were performed in guard cells from WS, GDP-ß-S pre-treated WS, gpa1-1 and gpa1-2 using non-invasive micro-test technique (NMT) and confocal technique. It was observed that the MeJA-induced stomatal closure was abolished in guard cells of gpa1 mutants. GDP-ß-S pre-treatment and gpa1 mutants impaired the MeJA-activated H+ efflux, Ca2+ influx and K+ efflux. The accumulation of ROS in gpa1-1 and gpa1-2 guard cells was also lower than that in WS guard cells under MeJA treatment. These results suggested that Gα subunits are involved in regulating the signal events in JA signal pathway and stomatal closure.

7.
J Chromatogr B Analyt Technol Biomed Life Sci ; 837(1-2): 101-7, 2006 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-16716773

RESUMO

A method for simultaneous analysis of lipids extracted from photosystem I complex was developed with high performance liquid chromatography/electrospray ionization mass spectrometry. The photosystem I complex was firstly solubilized and separated using deoxycholate polyacrylamide gel electrophoresis method after ultrasonic treatment of the sample (leaves of pea, Pisum sativum L.). The Photosystem I complexes were electrophoretically eluted from the deoxycholate polyacrylamide gel electrophoresis bands containing them, and the electron transport activity of the eluent measured as confirmation. Lipids, which were isolated from the complex having photosystem I activity, were separated and characterized with high performance liquid chromatography/electrospray ionization mass spectrometry. Five lipids, monogalactosyldiacylglycerol, digalactosyldiacylglycerol, phosphatidylglycerol, sulphoquinovosyldiacylglycerol and phosphaditylcholine were found combining with photosystem I complex. Different species of these lipids were found in the ESI mass spectra and the compositions of the acyl groups in them were determined.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Lipídeos/isolamento & purificação , Complexo de Proteína do Fotossistema I/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Eletroforese em Gel de Poliacrilamida , Pisum sativum/química
8.
J Chromatogr A ; 1072(2): 279-82, 2005 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-15887499

RESUMO

Efficient, rapid and inexpensive methods were established for the chiral separation of two glucopyranosyl compounds from plant extracts, by capillary zone electrophoresis (CZE). Baseline separation was achieved for both compounds. Several native cyclodextrins and their derivatives were tried as chiral selectors. CM-beta-CD and HP-beta-CD (with addition of acetonitrile in the buffer) gave rise to optimal chiral separation for the two compounds, respectively, each within a few minutes. The effects of several parameters on the chiral separation were studied.


Assuntos
Eletroforese Capilar/métodos , beta-Ciclodextrinas/química , Estereoisomerismo
9.
Artigo em Inglês | MEDLINE | ID: mdl-12237714

RESUMO

As a preliminary but important step in the investigation of the function of the new androgen-dependent DNA binding cytosol protein (C(3)P(4)) discovered by using gel retardation assay with a 31 bp fragment of DNA of the promoter of the rat ventral prostatic binding protein (PSBP) C(3) gene as a probe, a general survey was carried out on the tissue distribution of this protein in rat mice, rabbit and monkey of both sexes and also in some human pathological tissues with the following findings: (1) C(3)P(4) is present in all the male sex organs in different amount, but none in female sex organs. (2) C(3)P(4) has been found in the brain of all the species studied. (3) Its occurrence in other tissues are rare and show species variation, but no sex difference. (4) Of the samples collected from 8 different human pathological tissues, stomach cancer, both benign and malignant mammary tumors and three of the benign prostatic hyperplasia tissues revealed certain changes, the potential significance of these findings were discussed.

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