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1.
J Asian Nat Prod Res ; : 1-9, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38389314

RESUMO

Two new aporphine alkaloids, 6aR-2'-(3-oxobutenyl)-thaliadin (1) and N-methylthalisopynine (2), along with ten known analogs (3-12), were isolated from the roots of Thalictrum omeiense W. T. Wang et S. H. Wang. Their structures were determined by extensive spectroscopic and X-ray crystallographic analyses. Compounds 1-7 and 9-12 were tested for their antiproliferative effects in vitro against two human cancer cell lines (A549 and MCF-7). Among them, compounds 1, 3, and 7 exhibited moderate inhibitory activity against the tested cell lines with IC50 values ranging from 23.73 to 34.97 µM.

2.
Int J Mol Sci ; 24(22)2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-38003725

RESUMO

With global warming, high temperatures have become a major environmental stress that inhibits plant growth and development. Plants evolve several mechanisms to cope with heat stress accordingly. One of the important mechanisms is the Hsf (heat shock factor)-Hsp (heat shock protein) signaling pathway. Therefore, the plant transcription factor Hsf family plays important roles in response to heat stress. All Hsfs can be divided into three classes (A, B, and C). Usually, class-A Hsfs are transcriptional activators, while class-B Hsfs are transcriptional repressors. In potato, our previous work identified 27 Hsfs in the genome and analyzed HsfA3 and HsfA4C functions that promote potato heat resistance. However, the function of HsfB is still elusive. In this study, the unique B5 member StHsfB5 in potato was obtained, and its characterizations and functions were comprehensively analyzed. A quantitative real-time PCR (qRT-PCR) assay showed that StHsfB5 was highly expressed in root, and its expression was induced by heat treatment and different kinds of phytohormones. The subcellular localization of StHsfB5 was in the nucleus, which is consistent with the characterization of transcription factors. The transgenic lines overexpressing StHsfB5 showed higher heat resistance compared with that of the control nontransgenic lines and inhibitory lines. Experiments on the interaction between protein and DNA indicated that the StHsfB5 protein can directly bind to the promoters of target genes small Hsps (sHsp17.6, sHsp21, and sHsp22.7) and Hsp80, and then induce the expressions of these target genes. All these results showed that StHsfB5 may be a coactivator that promotes potato heat resistance ability by directly inducing the expression of its target genes sHsp17.6, sHsp21, sHsp22.7, and Hsp80.


Assuntos
Proteínas de Ligação a DNA , Solanum tuberosum , Proteínas de Ligação a DNA/metabolismo , Solanum tuberosum/genética , Solanum tuberosum/metabolismo , Fatores de Transcrição de Choque Térmico/genética , Fatores de Transcrição de Choque Térmico/metabolismo , Sequência de Aminoácidos , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Resposta ao Choque Térmico/genética , Plantas/metabolismo , Regulação da Expressão Gênica de Plantas
3.
Microorganisms ; 11(10)2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37894133

RESUMO

The Tibetan Plateau, known as the "Roof of the World" and "The Third Pole", harbors numerous saline lakes primarily distributed in the Northern Tibetan Plateau. However, the challenging conditions of high altitude, low oxygen level, and harsh climate have limited investigations into the actinobacteria from these saline lakes. This study focuses on investigating the biodiversity and bioactive secondary metabolites of cultivable actinobacteria isolated from the sediments of four saline lakes on the Northern Tibetan Plateau. A total of 255 actinobacterial strains affiliated with 21 genera in 12 families of 7 orders were recovered by using the pure culture technique and 16S rRNA gene phylogenetic analysis. To facilitate a high-throughput bioactivity evaluation, 192 isolates underwent OSMAC cultivation in a miniaturized 24-well microbioreactor system (MATRIX cultivation). The antibacterial activity of crude extracts was then evaluated in a 96-well plate antibacterial assay. Forty-six strains demonstrated antagonistic effects against at least one tested pathogen, and their underlying antibacterial mechanisms were further investigated through a dual-fluorescent reporter assay (pDualrep2). Two Streptomyces strains (378 and 549) that produce compounds triggering DNA damage were prioritized for subsequent chemical investigations. Metabolomics profiling involving HPLC-UV/vis, UPLC-QTOF-MS/MS, and molecular networking identified three types of bioactive metabolites belonging to the aromatic polyketide family, i.e., cosmomycin, kidamycin, and hedamycin. In-depth analysis of the metabolomic data unveiled some potentially novel anthracycline compounds. A genome mining study based on the whole-genome sequences of strains 378 and 549 identified gene clusters potentially responsible for cosmomycin and kidamycin biosynthesis. This work highlights the effectiveness of combining metabolomic and genomic approaches to rapidly identify bioactive chemicals within microbial extracts. The saline lakes on the Northern Tibetan Plateau present prospective sources for discovering novel actinobacteria and biologically active compounds.

4.
Heliyon ; 9(2): e13150, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36747524

RESUMO

There has newly been a lot of interest in higher education literature and policy on the notions of learner engagement and disengagement. Learner disengagement is a continuous difficulty in academic circumstances. To mitigate learners' disengagement, some factors seem interesting to be taken into consideration by scholars. One of them is mindfulness, defined as a resting strategy that is related to constructive influences when utilized as a coping mechanism for anxiety and apprehension. Furthermore, compassion is another factor that is regarded as a central dimension of the exercise of mindfulness. It refers to understanding how to be available, compassionate, and sympathetic towards oneself and others. Regarding the significance of these factors, the objective of this review is to investigate the role of mindfulness and compassion in reducing learners' educational disengagement in language education. Finally, future directions as well as educational implications for educational stakeholders are introduced following this review.

5.
Occup Ther Int ; 2022: 8399938, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36212086

RESUMO

This paper uses the theory of mental health education to conduct an in-depth study and analysis of teachers' educational management, and based on this, it designs a survey method on teachers' status and analyzes its strategic methods based on the results of the survey. Using literature analysis, questionnaires, survey interviews, and statistical analysis, the analysis of mental health of primary and secondary school teachers in the city was made. The results of the survey and analysis of the questionnaire results were used to construct a compatible mental health evaluation model. It was found that the overall level of elementary school teachers' mental health is poor at present, and different levels of mental health were presented with school sections and ages. A total of 286 questionnaires were distributed, 278 valid questionnaires were returned, and statistical analysis was conducted using EXCEL tables based on the collected data. The data analysis results show that the mental health level of teachers in middle school is significantly lower than that of teachers in primary school, and the mental health level of teachers in primary and secondary schools decreases with the increase of age. Therefore, to prevent the small and the gradual, start from the source; do a good job in the publicity of mental health education in peacetime; popularize the knowledge of mental health, so that teachers have a correct understanding of mental health education; improve the professional level of teachers; set up professional teachers in professional positions; establish sound job system and evaluation system, etc. Promote the balanced development of school psychological counseling rooms, strengthen the construction of professional teachers in mental health education, improve various systems of mental health education, comprehensively popularize teachers' mental health education and training, and mobilize teachers' enthusiasm for scientific research on mental health education. Improve the understanding of mental health education in colleges and universities, and regard mental health education as the foundation of all education.


Assuntos
Análise de Dados , Terapia Ocupacional , Educação em Saúde , Humanos , Professores Escolares/psicologia , Inquéritos e Questionários
6.
Zhongguo Zhong Yao Za Zhi ; 47(10): 2676-2680, 2022 May.
Artigo em Chinês | MEDLINE | ID: mdl-35718486

RESUMO

The chemical constituents from the roots of Thalictrum cultratum and T. baicalense were investigated. By various isolation methods, such as silica gel, aluminium oxide, ODS, and Sephadex LH-20 column chromatographies, and semi-preparative HPLC, 11 simple isoquinoline alkaloids were isolated from the ethanol extract of the roots of these two plants, including a new compound, named dehydrothalflavine(1), and ten known ones(2-11): N-methylcorydaline(2), N-methylthalidaldine(3), thaliflavine(4), oxyhydrastinine(5), noroxyhydrastinine(6), dimethoxyisoquinolone(7), thalactamine(8), dehydronoroxyhydrastinine(9), 6,7-dimethoxy-2-methyl-1,2,3,4-tetrahydroisoquinoline(10), and isopicnarrhine(11). Their structures were elucidated on the basis of HR-ESI-MS and 1 D and 2 D NMR techniques. Compound 1 was a new isoquinoline alkaloid. Compound 11 was obtained from Tha-lictrum plant for the first time. All compounds did not show cytotoxic activities against HL-60, U937, HCT116, Caco-2, and HepG2 cancer cell lines.


Assuntos
Alcaloides , Thalictrum , Alcaloides/análise , Células CACO-2 , Humanos , Isoquinolinas/farmacologia , Raízes de Plantas/química , Thalictrum/química
7.
Int J Syst Evol Microbiol ; 71(12)2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34889730

RESUMO

A Gram-stain-positive, aerobic, non-motile, non-spore-forming and coccus-shaped strain, designated strain G463T, was isolated from the rhizosphere soil of Salicornia europaea L. collected from Lake Gudzhirganskoe in Siberia. Based on 16S rRNA gene phylogeny, strain G463T belonged to the genus Hoyosella, with the highest 16S rRNA gene sequence similarity to Hoyosella altamirensis DSM 45258T (96.1%). The major fatty acids were C17:1 ω8c, C16:0, C15 : 0 and C17:0. The strain contained meso-diaminopimelic acid as the cell-wall diagnostic diamino acid and arabinose, galactose and ribose as the whole-cell sugars. MK-8 and MK-7 were the predominant menaquinones. The polar lipid profile comprised diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol, one unidentified phosphoglycolipid, two unidentified glycolipids and several unidentified lipids. Acetyl was the muramyl residue. Mycolic acids (C28-C34) were present. The G+C content of the genomic DNA was 68.3 mol%. Based on its phylogenetic, phenotypic and chemotaxonomic features, strain G463T was considered to represent a novel species of the genus Hoyosella, for which the name Hoyosella lacisalsi sp. nov. is proposed. The type strain is G463T (=JCM 33650T=CGMCC 1.17230T).


Assuntos
Lagos , Mycobacteriaceae/classificação , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Lagos/microbiologia , Mycobacteriaceae/isolamento & purificação , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Sibéria , Vitamina K 2/química
8.
Int J Syst Evol Microbiol ; 71(10)2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34662266

RESUMO

A Gram-stain-negative, non-motile, ellipsoid bacterium, designated HB182678T, was isolated from brown alga collected from Hainan province, PR China. Growth was observed at 10-50 °C (optimum 37-40 °C), at pH 6-10 (optimum pH 8) and in the presence of 0.5-13% (w/v) NaCl (optimum, 2-4%). The predominant isoprenoid quinone was Q-10 and the major fatty acids were C18 : 1 ω7c, C16 : 0, C18 : 0 and C19 : 0 cyclo ω8c. The polar lipids contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylmethylethanolamine, an unidentified phospholipid, two unidentified glycolipids and three unidentified aminophospholipids. The size of the draft genome was 4.40 Mbp with G+C content 68.8 mol%. Phylogenetic analysis of 16S rRNA gene sequence indicated that strain HB182678T belonged to the genus Mangrovicoccus, and the closest phylogenetically related species was Mangrovicoccus ximenensis T1lg56T (with the similarity of 96.3%). Whole genome average nucleotide identity (ANI) value between them was 84.3% and in silico DNA-DNA hybridization value was 27.2%. The combined phylogenetic relatedness, phenotypic and genotypic features supported the conclusion that strain HB182678T represents a novel species of the genus Mangrovicoccus, for which the name Mangrovicoccus algicola sp. nov. is proposed. The type strain is HB182678T (=MCCC 1K04624T=KCTC 82318T).


Assuntos
/microbiologia , Filogenia , Polissacarídeo-Liases , Rhodobacteraceae/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Fosfolipídeos , RNA Ribossômico 16S/genética , Rhodobacteraceae/enzimologia , Rhodobacteraceae/isolamento & purificação , Análise de Sequência de DNA , Ubiquinona/análogos & derivados , Ubiquinona/química
9.
J Exp Bot ; 2021 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-34240135

RESUMO

Chilling is a major stress to plants of subtropical and tropical origins including maize (Zea mays L.). To reveal molecular mechanisms underlying chilling tolerance and survival, we investigated transcriptomic responses to chilling stress in differentiated leaves and roots as well as in crowns with meristem activity in maize. Chilling stress on shoots and roots is found to each contributes to seedling lethality in maize. Comparison of maize lines with different chilling tolerance capacities reveals that chilling survival is highly associated with upregulation of abscisic acid biosynthesis and response as well as transcriptional regulators in leaves and crowns. It is also associated with the downregulation of translation in leaves and heat response in crowns. Chilling treatment on whole or part of the plants reveals that response to distal-chilling is very distinct from, and sometimes opposite to, response to local- or whole-plant chilling in both leaves and roots, suggesting a communication between shoots and roots in environmental response. This study thus provides transcriptomic responses in leaves, roots and crowns under differential chilling stresses in maize and reveals potential chilling tolerance and survival mechanisms which lays ground for improving chilling tolerance in crop plants.

10.
Plant Cell Physiol ; 61(5): 933-941, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32091601

RESUMO

We report here the interactive effects of three light qualities (white, red and blue) and three growth temperatures (16�C, 22�C and 28�C) on rosette growth, hypocotyl elongation and disease resistance in Arabidopsis thaliana. While an increase in temperature promotes hypocotyl elongation irrespective of light quality, the effects of temperature on rosette growth and disease resistance are dependent on light quality. Maximum rosette growth rate under white, red and blue light are observed at 28�C, 16�C and 22�C, respectively. The highest disease resistance is observed at 16�C under all three light conditions, but the highest susceptibility is observed at 28�C for white light and 22�C for red and blue light. Interestingly, rosette growth is inhibited by phytochrome B (PHYB) under blue light at 28�C and by cryptochromes (CRYs) under red light at 16�C. In addition, disease resistance is inhibited by PHYB under blue light and promoted by CRYs under red light. Therefore, this study reveals a complex interaction between light and temperature in modulating rosette growth and disease resistance as well as the contribution of PHYB and CRY to disease resistance.


Assuntos
Arabidopsis/imunologia , Luz , Temperatura , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/efeitos da radiação , Proteínas de Arabidopsis/metabolismo , Resistência à Doença , Hipocótilo/crescimento & desenvolvimento , Hipocótilo/efeitos da radiação , Análise Multivariada , Fenótipo , Doenças das Plantas , Imunidade Vegetal/efeitos da radiação
11.
Int J Syst Evol Microbiol ; 70(1): 77-82, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31535960

RESUMO

A Gram-stain-positive, aerobic, non-motile, rod-shaped actinobacterium, designated strain 21Sc5-5T, was isolated from a soil sample collected in the Taklamakan desert in Xinjiang Uygur Autonomous Region, PR China and investigated by using a polyphasic approach. Strain 21Sc5-5T grew at 10-37 °C (optimum, 28-30 °C), pH 6.0-9.0 (optimum, pH 7.0) and in the presence of 0-3 % (w/v) NaCl (optimum, 0 %). Phylogenetic analysis based on 16S rRNA gene sequences suggested that strain 21Sc5-5T formed a distinct lineage within the genus Nocardioides and had the highest similarity to Nocardioides albidus THG-S11.7T (97.30 %), followed by Nocardioides kongjuensis A2-4T (97.22 %), Nocardioides nitrophenolicus NSP 41T (97.15 %) and Nocardioides caeni MN8T (97.15 %). The results of chemotaxonomic analyses showed that the isolate possessed ll-diaminopimelic acid as the diagnostic diamino acid of the peptidoglycan and MK-8(H4) as the predominant menaquinone. The polar lipids comprised diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, an unidentified phospholipid and three unidentified lipids. The major fatty acids were iso-C16 : 0 and 10-methyl C18 : 0. The genome length of strain 21Sc5-5T was 4.67 Mb containing 372 contigs and with a DNA G+C content of 70.4 mol%. On the basis of data from phylogenetic, phenotypic and chemotaxonomic analyses, strain 21Sc5-5T represents a novel species of the genus Nocardioides, for which the name Nocardioides vastitatis sp. nov. is proposed. The type strain is 21Sc5-5T (=JCM 33365T=CGMCC 4.7608T).


Assuntos
Actinobacteria/classificação , Clima Desértico , Filogenia , Microbiologia do Solo , Actinobacteria/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , China , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
12.
3 Biotech ; 9(11): 432, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31696037

RESUMO

WD-repeat (WDR) proteins are highly abundant and participate in a seemingly wide range of interactions and cellular functions acting as scaffolding molecules. However, WDR identification in potato has not been conducted so far. In this study, we demonstrated the presence of at least 168 WDR genes in potato (Solanum tuberosum L.) which can be subdivided into five discrete clusters (Cluster I-V) and 10 classes inferred from their phylogenetic features of the constituent genes and the distribution of domains. These genes are distributed on all 12 chromosomes, of which chromosome 3 carries the most genes with 26 StWDRs. The expression of potato WDR genes showed tissue specificity with a high expression in carpels, callus and roots, and the expression patterns were obviously different among different genes. Transcript profiling of 168 StWDR genes revealed the particular tissues in which the 168 StWDR are expressed, and displayed a high expression in carpels, callus and roots. Most StWDRs were modulated by salt, ABA and Verticillium dahliae stresses, of which StWD092 was found to be highly expressed under all the three stresses. These outcomes revealed the intricate crosstalk between WDRs and other regulatory networks in the event of adverse milieu.

13.
J Nat Prod ; 80(11): 2893-2904, 2017 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-29131616

RESUMO

Inspired by the intriguing structures and bioactivities of dimeric alkaloids, 11 new thalifaberine-type aporphine-benzylisoquinoline alkaloids, thalicultratines A-K, a tetrahydroprotoberberine-aporphine alkaloid, thalicultratine L, and five known ones were isolated from the roots of Thalictrum cultratum. Their structures were defined on the basis of NMR and HRESIMS data. The antiproliferative activities of compounds 1-17 were evaluated against human leukemia HL-60 and prostate cancer PC-3 cells. Most alkaloids showed potent cytotoxicity against selected cancer cells. Preliminary SARs are discussed. The most active new compound (3), with an IC50 value of 1.06 µM against HL-60 cells, was selected for mechanism of action studies. The results revealed that compound 3 induced apoptosis and arrested the HL-60 cell cycle at the S phase with the loss of mitochondria membrane potential. The nuclear morphological Hoechst 33258 staining assay was also carried out, and the results confirmed apoptosis.


Assuntos
Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Aporfinas/isolamento & purificação , Aporfinas/farmacologia , Medicamentos de Ervas Chinesas/isolamento & purificação , Medicamentos de Ervas Chinesas/farmacologia , Raízes de Plantas/química , Thalictrum/química , Alcaloides/química , Antineoplásicos Fitogênicos/química , Aporfinas/química , Alcaloides de Berberina , Medicamentos de Ervas Chinesas/química , Células HL-60 , Humanos , Concentração Inibidora 50 , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Relação Estrutura-Atividade
14.
Front Pharmacol ; 8: 315, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28611667

RESUMO

Increasing evidence indicates the occurrence of cognitive impairment in astronauts under spaceflight compound conditions, but the underlying mechanisms and countermeasures need to be explored. In this study, we found that learning and memory abilities were significantly reduced in rats under a simulated long-duration spaceflight environment (SLSE), which includes microgravity, isolation confinement, noises, and altered circadian rhythms. Dammarane sapogenins (DS), alkaline hydrolyzed products of ginsenosides, can enhance cognition function by regulating brain neurotransmitter levels and inhibiting SLSE-induced neuronal injury. Bioinformatics combined with experimental verification identified that the PI3K-Akt-mTOR pathway was inhibited and the MAPK pathway was activated during SLSE-induced cognition dysfunction, whereas DS substantially ameliorated the changes in brain. These findings defined the characteristics of SLSE-induced cognitive decline and the mechanisms by which DS improves it. The results provide an effective candidate for improving cognitive function in spaceflight missions.

15.
J Proteomics ; 146: 14-24, 2016 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-27321579

RESUMO

UNLABELLED: To date, transcriptome profile analysis of maize seedlings in response to cold stress have been well documented; however, changes in protein species abundance of maize seedlings in response to cold stress are still unknown. Herein, leaves from the maize inbred line W9816 (a cold-resistance genotype) were harvested at three-leaf stage, and were used to identify the differential abundance protein species (DAPS) between chilling stress (4°C) and control conditions (25°C). iTRAQ-based quantitative proteomic were used in this study. As a result, 173 DAPS were identified after chilling stress. Bioinformatic analysis showed that 159 DAPS were annotated in 38 Gene Ontology functional groups, 108 DAPS were classified into 20 clusters of orthologous groups of protein categories, 99 DAPS were enrichment in KEGG pathways. Antioxidants assays validated that the iTRAQ results were reliable. Based on functional analysis, we concluded that the adaptive response of maize seedlings to chilling stress might be related to alleviation of photodamage caused by the over-energized state of thylakoid membrane, more energy produced through glycolysis, increased abundance of stress-responsive protein species, and improvement in the overall ability to scavenge ROS. Posttranscriptional regulation and posttranslational modifications also play important roles for maize to adapt to chilling stress. BIOLOGICAL SIGNIFICANCE: The major challenge for maize breeders is the complexity of the response to chilling stress. Although extensive researches have been focus on maize chilling stress using segregating populations, epigenetics, transcriptomics, molecular biology, however, the molecular mechanism of chilling stress in maize remains to be further elucidated. In the present paper, a differential proteomic analysis was performed and the results revealed the adaptive response of maize seedlings to chilling stress might be related to alleviation of photodamage caused by the over-energized state of thylakoid membrane, more energy produced through glycolysis, increased abundance of stress-responsive protein species, improvement in the overall ability to scavenge ROS, including detoxifying enzymes and antioxidants. Posttranscriptional regulation and posttranslational modifications also play important roles for maize to adapt to chilling stress. This approach identified new protein species involved in posttranslational modifications, signal transduction, lipid metabolism, inorganic ion transport and metabolism and other biological processes that were not previously known to be associated with chilling stress response.


Assuntos
Adaptação Fisiológica , Redes e Vias Metabólicas , Proteômica/métodos , Estresse Fisiológico , Zea mays/metabolismo , Temperatura Baixa , Regulação da Expressão Gênica de Plantas , Folhas de Planta/química , Proteínas de Plantas/análise , Proteínas de Plantas/metabolismo , Plântula/metabolismo , Zea mays/embriologia
17.
Plant Cell Rep ; 35(8): 1671-86, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27061906

RESUMO

KEY MESSAGE: A Sec14-like protein, ZmSEC14p , from maize was structurally analyzed and functionally tested. Overexpression of ZmSEC14p in transgenic Arabidopsis conferred tolerance to cold stress. Sec14-like proteins are involved in essential biological processes, such as phospholipid metabolism, signal transduction, membrane trafficking, and stress response. Here, we reported a phosphatidylinositol transfer-associated protein, ZmSEC14p (accession no. KT932998), isolated from a cold-tolerant maize inbred line using the cDNA-AFLP approach and RACE-PCR method. Full-length cDNA that consisted of a single open reading frame (ORF) encoded a putative polypeptide of 295 amino acids. The ZmSEC14p protein was mainly localized in the nucleus, and its transcript was induced by cold, salt stresses, and abscisic acid (ABA) treatment in maize leaves and roots. Overexpression of ZmSEC14p in transgenic Arabidopsis conferred tolerance to cold stress. This tolerance was primarily displayed by the increased germination rate, root length, plant survival rate, accumulation of proline, activities of antioxidant enzymes, and the reduction of oxidative damage by reactive oxygen species (ROS). ZmSEC14p overexpression regulated the expression of phosphoinositide-specific phospholipase C, which cleaves phosphatidylinositol 4,5-bisphosphate (PIP2) and generates second messengers (inositol 1,4,5-trisphosphate and 1,2-diacylglycerol) in the phosphoinositide signal transduction pathways. Moreover, up-regulation of some stress-responsive genes such as CBF3, COR6.6, and RD29B in transgenic plants under cold stress could be a possible mechanism for enhancing cold tolerance. Taken together, this study strongly suggests that ZmSEC14p plays an important role in plant tolerance to cold stress.


Assuntos
Temperatura Baixa , Proteínas de Transferência de Fosfolipídeos/metabolismo , Proteínas de Plantas/metabolismo , Zea mays/metabolismo , Ácido Abscísico/farmacologia , Adaptação Fisiológica/efeitos dos fármacos , Adaptação Fisiológica/genética , Sequência de Aminoácidos , Antioxidantes/metabolismo , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Arabidopsis/fisiologia , Congelamento , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas , Germinação/efeitos dos fármacos , Proteínas de Fluorescência Verde/metabolismo , Cebolas/citologia , Fosfoinositídeo Fosfolipase C/metabolismo , Proteínas de Transferência de Fosfolipídeos/química , Proteínas de Transferência de Fosfolipídeos/genética , Proteínas de Transferência de Fosfolipídeos/isolamento & purificação , Filogenia , Epiderme Vegetal/citologia , Epiderme Vegetal/efeitos dos fármacos , Folhas de Planta/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/isolamento & purificação , Plantas Geneticamente Modificadas , Prolina/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Sementes/efeitos dos fármacos , Sementes/crescimento & desenvolvimento , Cloreto de Sódio/farmacologia , Estresse Fisiológico/efeitos dos fármacos , Estresse Fisiológico/genética , Frações Subcelulares/metabolismo , Zea mays/efeitos dos fármacos , Zea mays/genética , Zea mays/fisiologia
18.
Arch Pharm Res ; 39(2): 172-177, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26659874

RESUMO

Three new xanthones, paucinervins H-J (1-3), as well as eleven known compounds (4-14), were isolated from the leaves of Garcinia paucinervis. The structures of the new compounds (1-3) were elucidated by 1D, 2D NMR spectra and HR ESIMS. In vitro antiproliferative activity against human promyelocytic leukemia HL-60 cells was tested, among which, compounds 2, 5, 6 and 7 exhibited strong growth inhibitory effects with GI50 values ranging from 1.30 to 9.08 µM, respectively. Preliminary SARs were also discussed.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Garcinia/química , Leucemia Promielocítica Aguda/tratamento farmacológico , Extratos Vegetais/farmacologia , Xantonas/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Relação Dose-Resposta a Droga , Células HL-60 , Humanos , Concentração Inibidora 50 , Leucemia Promielocítica Aguda/metabolismo , Estrutura Molecular , Fitoterapia , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Plantas Medicinais , Relação Estrutura-Atividade , Xantonas/química , Xantonas/isolamento & purificação
19.
Nat Prod Res ; 30(2): 125-30, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25981853

RESUMO

A new 2(1H)-pyrazinone ring-containing natural product, paenibacillin A (1), together with five known diketopiperazine derivatives 2-6 and two known isoflavones 7-8, was isolated from the culture of an endophytic bacterium Paenibacillus sp. Xy-2. The structure of compound 1 was elucidated by extensive spectral methods, including UV, IR, HR-ESI-MS, 1D and 2D NMR and ECD experiments. Compound 1 exhibited moderate cytotoxicity against HL-60 cell line with IC50 value of 50.48 µM.


Assuntos
Paenibacillus/química , Pirazinas/química , Pirazinas/farmacologia , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Endófitos/química , Células HL-60/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Isoflavonas/química , Isoflavonas/isolamento & purificação , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Pirazinas/isolamento & purificação , Espectrometria de Massas por Ionização por Electrospray
20.
J Nat Med ; 70(2): 173-8, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26645396

RESUMO

Three new prenylated xanthones, garcinexanthones G-I (1-3), together with fifteen known ones (4-18) were identified from the leaves of Garcinia lancilimba. Their structures were determined by extensive spectroscopic analyses. Most of the compounds exhibited inhibitory effects against HL-60 (human leukemia), A549 (human lung cancer), and MCF-7 (human breast cancer) cell lines. Among them, compounds 7, 17, and 13 exhibited the most pronounced growth inhibitory activity against HL-60, A549, and MCF-7 cell lines with GI50 values of 1.68, 4.88, and 6.28 µM, respectively.


Assuntos
Garcinia/química , Xantonas/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Feminino , Células HL-60 , Humanos , Leucemia/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Células MCF-7 , Fitoterapia , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Folhas de Planta/química , Prenilação , Xantonas/química , Xantonas/farmacologia , Xantonas/uso terapêutico
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