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1.
Nat Prod Commun ; 7(4): 431-4, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22574435

RESUMO

Two samples of Ligularia kanaitzensis collected in the Shizhongshan Mountain region of Yunnan Province, as well as one sample collected in Sichuan Province, were analyzed with regard to root constituents and neutral DNA sequences. The two Shizhongshan samples were found to be different from each other and from other samples analyzed previously, indicating that the intra-specific diversity in the species was highly complex.


Assuntos
Asteraceae/química , Asteraceae/genética , China , Variação Genética , Geografia
2.
Chem Biodivers ; 9(4): 789-805, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22492496

RESUMO

The chemical constituents of the root extracts and the evolutionarily neutral DNA base sequences were studied for 28 samples of Ligularia duciformis, L. kongkalingensis, and L. nelumbifolia collected in Sichuan and Yunnan Provinces of China. The samples could be classified into four chemotypes (1-4). Sesquiterpenoids having eremophilane and oplopane skeletons were isolated from two (Chemotype 1) and three (Chemotype 2) samples, respectively. Two new oplopane derivatives were isolated and their structures were determined. In 18 samples, phenylpropenoids were the major components (Chemotype 3). In five samples, neither phenylpropenoids nor sesquiterpenoids were found (Chemotype 4). Despite this large chemical variety, no correlation was found between the chemotype and the morphological criteria of species identification. The analysis of the evolutionarily neutral DNA regions also indicated that the samples were not separated into distinct clades and that introgression was extensive.


Assuntos
Asteraceae/química , Asteraceae/genética , DNA de Plantas/genética , Sequência de Bases , China , Evolução Molecular , Dados de Sequência Molecular , Naftalenos/química , Raízes de Plantas/química , Raízes de Plantas/genética , Sesquiterpenos Policíclicos , Análise de Sequência de DNA , Sesquiterpenos/química
3.
Chem Biodivers ; 6(12): 2184-91, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20020450

RESUMO

The chemical composition of the root extract and neutral base sequences of L. hodgsonii samples collected in Japan and China were examined. From the Japanese and the Chinese samples, 6beta-(angeloyloxy)furanoeremophilan-15-oic acid and 3beta-acetoxy-6beta-[(2-methylbutanoyl)oxy]furanoeremophilan-10beta-ol were isolated as the major component, respectively. The sequence of the internal transcribed spacers (ITSs) of the ribosomal RNA gene was different in the Japanese and the Chinese samples. In contrast to the significant genetic difference, chemical diversity was limited to the positions of O-functionalities on the furanoeremophilane skeleton, supporting our hypothesis that the production of furanoeremophilanes is ecologically advantageous.


Assuntos
Asteraceae/química , Asteraceae/genética , Sequência de Bases , China , Japão , Raízes de Plantas/química , Raízes de Plantas/genética , RNA de Plantas/genética , RNA de Plantas/metabolismo , Sesquiterpenos/química
4.
Chem Biodivers ; 4(9): 2210-7, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17886839

RESUMO

The chemical constituents of the root extracts and the nucleotide sequences of the atpB-rbcL intergenic region of Ligularia latihastata and L. villosa, collected in northwestern Yunnan Province, were studied. In the twelve collected samples of L. latihastata, two major benzofurans, 5,6-dimethoxy-2-(1-methylethenyl)-1-benzofuran (1) and euparin (2) were detected as major components. The minor compound (2R*,3S*)-5-acetyl-2,3-dihydro-6-hydroxy-2-(1-methylethenyl)-1-benzofuran-3-yl (2Z)-2-[(acetoxy)methyl]but-2-enoate (4) was found to be susceptible to artifact formation upon extraction with EtOH. The intra-specific diversity in chemical composition of the samples was small, but the diversity in the atpB-rbcL sequence was fairly large. Compounds 1 and 2 were also found in the three collected samples of L. villosa, indicating that the two species are chemically close to each other, in agreement with morphological taxonomy.


Assuntos
Asteraceae/química , Asteraceae/genética , Benzofuranos/análise , Butiratos/análise , China , Variação Genética , Raízes de Plantas/química , Raízes de Plantas/genética , Análise de Sequência de DNA
5.
Chem Biodivers ; 4(3): 500-7, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17372952

RESUMO

The intraspecific diversity in L. tsangchanensis collected in the Chinese Provinces Yunnan and southwestern Sichuan was studied by chemical and genetic approaches. The samples collected in Yunnan were found to contain cacalol (1) as the sole major component, while samples from Sichuan contained 7alpha- and 7beta-eremophila-9,11-dien-8-one (5 and 6) as well as the 3alpha-angeloyloxy derivative 7 as major components. In addition, the sequences of the internal transcribed spacers (ITSs) of the ribosomal RNA gene indicated that the Yunnan and the Sichuan samples constitute separate clades. These results demonstrate that L. tsangchanensis in Yunnan and Sichuan are distinct.


Assuntos
Asteraceae/química , Asteraceae/genética , Variação Genética/genética , China , Extratos Vegetais/química , Extratos Vegetais/genética , Raízes de Plantas/química , Raízes de Plantas/genética
6.
Nucleic Acids Res ; 34(13): 3794-802, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16916790

RESUMO

A total of 10 B-lymphocyte-specific DNase I hypersensitive sites located in the chicken Ig-beta locus were divided into four regions and combinations of deletions of these regions were carried out. A decrease in transcription of the Ig-beta gene to <3% was demonstrated in cells with deletions in all four regions. The Ig-beta chromatin was resistant to DNase I digestion in these cells. Thus, the collaboration is shown to convert the Ig-beta chromatin from the condensed state to a relaxed state. H3 and H4 acetylation decreased to <8% but H3K4 hypermethylation was observed at the Ig-beta promoter and exon 3. The collaboration of four regions had virtually no effect on CG hypomethylation in the region upstream the transcriptional start site. Accordingly, neither the DNase I general sensitive state in the Ig-beta chromatin nor hyperacetylation of H3 and H4 histones in the promoter proximal region causes H3K4 di-methylation or CG hypomethylation in the promoter. From these analyses, a chromatin situation was found in which both an active state, such as enhanced H3K4 methylation, or CG hypomethylation, and an inactive state, such as DNase I resistance in the Ig-beta chromatin or hypoacetylation of H3 and H4 histones in the Ig-beta locus, coexist.


Assuntos
Antígenos CD79/genética , Galinhas/genética , Cromatina/química , Elementos Reguladores de Transcrição , Ativação Transcricional , Acetilação , Animais , Antígenos CD79/metabolismo , Linhagem Celular , Desoxirribonuclease I , Éxons , Histonas/metabolismo , Metilação , Regiões Promotoras Genéticas , RNA Mensageiro/metabolismo , Deleção de Sequência , Transcrição Gênica
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