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1.
Mol Biol Rep ; 45(4): 601-609, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29882084

RESUMO

Milk thistle (Silybum marianum) is among the world's popular medicinal plants. Start Codon Targeted (SCoT) marker system was utilized to investigate the genetic variability of 80 S. marianum genotypes from eight populations in Iran. SCoT marker produced 255 amplicons and 84.03% polymorphism was generated. The SCoT marker system's polymorphism information content value was 0.43. The primers' resolving power values were between 4.18 and 7.84. The percentage of polymorphic bands was between 33.3 and 100%. The Nei's gene diversity (h) was 0.19-1.30 with an average 0.72. The Shannon's index (I) ranged from 0.29 to 1.38 with an average value of 0.83. The average gene flow (0.37) demonstrated a high genetic variation among the studied populations. The variation of 42% was displayed by the molecular variance analysis among the populations while a recorded variation of 58% was made within the populations. Current investigation suggested that SCoT marker system could effectively evaluate milk thistle genotypes genetic diversity.


Assuntos
Marcadores Genéticos/genética , Cardo Mariano/genética , Análise por Conglomerados , Códon de Iniciação/genética , Primers do DNA , Fluxo Gênico/genética , Variação Genética/genética , Genética Populacional/métodos , Genótipo , Irã (Geográfico) , Filogenia , Polimorfismo Genético/genética
2.
Plant J ; 92(6): 995-1004, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28990236

RESUMO

Silymarin is a collection of compounds extracted from the medicinal herb milk thistle, among which silybin is the major flavonolignan. However, the biosynthesis pathway of silybin remains unclear. In this study, biomimetic reactions demonstrated that silybin can be synthesized from coniferyl alcohol and taxifolin by the action of peroxidase. The concentration profiles of silybin and its precursors and RNA-Seq analysis of gene expression revealed that the amount of taxifolin and the activity of peroxidase serve as the limiting factors in silybin biosynthesis. Hierarchical clustering of the expression profile of genes of the flavonoid biosynthesis pathway distinguished flowers from other organs. RNA-Seq revealed five candidates for the peroxidase involved in silybin production, among which APX1 (ascorbate peroxidase 1) showed a distinct peroxidase activity and the capacity to synthesize silybin. The spatial organization of silybin biosynthesis in milk thistle was elucidated, which could help our understanding of the biosynthesis of silybin and other flavonolignans.


Assuntos
Antioxidantes/metabolismo , Cardo Mariano/genética , Silimarina/metabolismo , Transcriptoma , Vias Biossintéticas , Flores/genética , Flores/metabolismo , Cardo Mariano/metabolismo , Plantas Medicinais , Silibina
3.
Plant Physiol Biochem ; 108: 191-202, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27448793

RESUMO

Silymarin, a Silybum marianum seed extract containing a mixture of flavonolignans including silybin, is being used as an antihepatotoxic therapy for liver diseases. In this study, the enhancing effect of gamma irradiation on plant growth parameters of S. marianum under salt stress was investigated. The effect of gamma irradiation, either as a single elicitor or coupled with salinity, on chalcone synthase (CHS) gene expression and silybin A + B yield was also evaluated. The silybin A + B content in S. marianum fruits was estimated by liquid chromatography-mass spectrometry (LC-MS/MS). An increase in silybin content was accompanied by up-regulation of the CHS1, CHS2 and CHS3 genes, which are involved in the silybin biosynthetic pathway. The highest silybin A + B production (0.77 g/100 g plant DW) and transcript levels of the three studied genes (100.2-, 91.9-, and 24.3-fold increase, respectively) were obtained with 100GY gamma irradiation and 4000 ppm salty water. The CHS2 and CHS3 genes were partially sequenced and submitted to the NCBI database under the accession numbers KT252908.1 and KT252909.1, respectively. Developing new approaches to stimulate silybin biosynthetic pathways could be a useful tool to potentiate the use of plants as renewable resources of medicinal compounds.


Assuntos
Aciltransferases/genética , Cardo Mariano/genética , Silimarina/metabolismo , Aciltransferases/metabolismo , Frutas/genética , Frutas/metabolismo , Raios gama , Regulação da Expressão Gênica de Plantas , Germinação , Cardo Mariano/metabolismo , Cardo Mariano/efeitos da radiação , Família Multigênica , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Medicinais/genética , Plantas Medicinais/metabolismo , Salinidade , Tolerância ao Sal , Sementes/crescimento & desenvolvimento , Silibina , Silimarina/genética
4.
J Plant Physiol ; 192: 111-7, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26905197

RESUMO

The hepatoprotectant flavonolignan silymarin (Sm) is synthesized through 4-coumaroyl-CoA, which enters both the flavonoid and the monolignol pathway giving the two immediate precursors taxifolin (Tx) and coniferyl alcohol (CA), respectively. Sm formation occurs via oxidative radicalization of Tx and CA and is accumulated at high levels at final stages of maturation of Silybum marianum fruits. By contrast, Sm production is severely reduced in cell cultures of this species, although suspensions are able to excrete Sm compounds into the medium upon elicitation with methyl jasmonate (MeJA) or cyclodextrins (CD). Knowledge of gene expression is important to understand Sm dynamics and to develop strategies aimed at increasing production by means of cell cultures but, to date, only one gene of the pathway (chalcone synthase, SmCHS) has been cloned. Therefore, to elucidate the relationship between expression of Sm pathway genes and production of these metabolites, four cDNA fragments of genes putatively involved in flavonolignan biosynthesis, chalcone isomerase, flavanone 3-hydroxylase, flavonol 3'-hydroxylase and cinnamyl alcohol dehydrogenase, were isolated from Sm producing S. marianum fruits and their expression, together with that of the SmCHS, were studied both in fruits at different maturation stages and in elicited cell suspensions. Combined results at both transcript expression and metabolite levels at three different stages of fruit maturation revealed that the formation of the flavonoid moiety precedes flavonolignan biosynthesis, being Sm accumulation associated to expression of the monolignol pathway. There was not detectable accumulation of transcripts in cell suspensions, however, elicitation with MeJA or CD notably induced expression of the studied fragments. These results indicate that the five genes expressed during maturation of S. marianum fruits may contribute to observed increases in flavonolignan accumulation upon treatment of cell cultures with elicitors.


Assuntos
Flavonolignanos/metabolismo , Cardo Mariano/fisiologia , Silimarina/metabolismo , Acetatos/metabolismo , Acil Coenzima A/genética , Acil Coenzima A/metabolismo , Aciltransferases/genética , Aciltransferases/metabolismo , Células Cultivadas , Ciclodextrinas , Ciclopentanos/metabolismo , Flavonoides/metabolismo , Frutas/genética , Frutas/fisiologia , Expressão Gênica , Cardo Mariano/genética , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/fisiologia , Oxilipinas/metabolismo , Proteínas de Plantas
5.
J Genet ; 94(4): 611-7, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26690515

RESUMO

Silymarin is a flavonoid compound derived from milk thistle (Silybum marianum) seeds which has several pharmacological applications. Chalcone synthase (CHS) is a key enzyme in the biosynthesis of flavonoids; thereby, the identification of CHS encoding genes in milk thistle plant can be of great importance. In the current research, fragments of CHS genes were amplified using degenerate primers based on the conserved parts of Asteraceae CHS genes, and then cloned and sequenced. Analysis of the resultant nucleotide and deduced amino acid sequences led to the identification of two different members of CHS gene family,SmCHS1 and SmCHS2. Third member, full-length cDNA (SmCHS3) was isolated by rapid amplification of cDNA ends (RACE), whose open reading frame contained 1239 bp including exon 1 (190 bp) and exon 2 (1049 bp), encoding 63 and 349 amino acids, respectively. In silico analysis of SmCHS3 sequence contains all the conserved CHS sites and shares high homology with CHS proteins from other plants.Real-time PCR analysis indicated that SmCHS1 and SmCHS3 had the highest transcript level in petals in the early flowering stage and in the stem of five upper leaves, followed by five upper leaves in the mid-flowering stage which are most probably involved in anthocyanin and silymarin biosynthesis.


Assuntos
Aciltransferases/genética , Regulação da Expressão Gênica de Plantas/genética , Genes de Plantas/genética , Cardo Mariano/genética , Sequência de Aminoácidos , Flores/genética , Dados de Sequência Molecular , Folhas de Planta/genética
6.
Zhongguo Zhong Yao Za Zhi ; 39(11): 2005-10, 2014 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-25272831

RESUMO

This research uses six Agrobacterium rhizogenes R1601, R15384, R1000, A4, R1025 and R1 to infect silymarin explants to induce hairy roots and silibin. All of the six A. rhizogenes can induce Silybum marianum to generate hairy roots and the A. rhizogene A4 shows comparatively high infection on the plant. This research determines the condition to induce silymarin hairy roots by the factors of infection time, pre-culturing, co-culturing and pH value. The fact that MS liquid medium fits the proliferation of silymarin hairy roots is determined. Through PCR molecular identification, it can be seen that the DNA plasmids in the A. rhizogenes are successfully integrated into the genome of transformed roots. Using liquid chromatography, it is determined that the silibin content in silymarin hairy roots is 2.5 times that in the plant In this research, the silymarin hairy roots culturing system is established, which lays a foundation for the study of culturing silymarin hairy roots and producing silibin.


Assuntos
Técnicas de Cultura de Células/métodos , Cardo Mariano/crescimento & desenvolvimento , Raízes de Plantas/química , Silimarina/análise , Agrobacterium/genética , Agrobacterium/fisiologia , Cardo Mariano/química , Cardo Mariano/genética , Cardo Mariano/microbiologia , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/microbiologia , Silibina , Transformação Genética
7.
Plant Physiol Biochem ; 70: 115-22, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23771036

RESUMO

Jasmonate and its methyl derivative, methyl jasmonate (MeJA), are naturally occurring compounds that mediate several plant physiological processes in response to pathogen attack, wounding, and ozone. Exogenous application of jasmonates triggers defense responses that resemble those initiated by pathogen infection and also modulates the production of certain secondary metabolites in a variety of plant species. In this study, we treated the hairy root cultures of Silybum marianum L. with 100 µM MeJA and then measured the content of Silymarin (SLM). We observed that the SLM content increased significantly after 48 h of MeJA treatment and remained constant for 120 h. However, MeJA treatment caused a significant growth reduction after 96 h incubation. The activity of lipoxygenase as a key enzyme in the jasmonate biosynthesis pathway and anti-oxidative enzymes; peroxidase and ascorbate peroxidase was also significantly increased after MeJA treatment. To elucidate the global effect of jasmonate on gene expression of S. marianum, we employed high resolution two-dimensional gel electrophoresis coupled with tandem mass spectrometry. Out of 670 reproducibly detected protein spots which were analyzed on each given gel, 32 spots were up- or down regulated upon MeJA treatment. Of them, ten proteins such as ER binding protein, glutamine synthetase, pathogenesis-related protein, caffeoyl CoA O-methyltransferase, and profilin-1 could be identified by mass spectrometry analysis. The possible implications of the identified proteins on physiological outcome of MeJA application in S. marianum hairy root culture will be discussed.


Assuntos
Acetatos/metabolismo , Ciclopentanos/metabolismo , Expressão Gênica/efeitos dos fármacos , Cardo Mariano/metabolismo , Oxilipinas/metabolismo , Reguladores de Crescimento de Planta/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/metabolismo , Proteoma/metabolismo , Acetatos/farmacologia , Antioxidantes/metabolismo , Ascorbato Peroxidases/metabolismo , Ciclopentanos/farmacologia , Lipoxigenase/metabolismo , Cardo Mariano/efeitos dos fármacos , Cardo Mariano/genética , Cardo Mariano/crescimento & desenvolvimento , Oxilipinas/farmacologia , Peroxidase/metabolismo , Desenvolvimento Vegetal/efeitos dos fármacos , Reguladores de Crescimento de Planta/farmacologia , Raízes de Plantas/efeitos dos fármacos , Proteômica/métodos , Silimarina/metabolismo
8.
Pak J Biol Sci ; 10(19): 3266-71, 2007 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-19090141

RESUMO

The aim of present study was to investigate the genetic variation within and between 32 milk thistle ecotypes collected from northern (23 accessions) and southern (9 accessions) regions of Iran along with two introduced varieties, CN seeds and Budakalaszi, for morphological and flavonolignans properties. The two collections were assessed at separate field experiments. MANOVA for all the morphological traits showed significant difference between ecotypes. Univariate ANOVA verified these differences for most of the traits in the northern ecotypes (first collection) while for southern ecotypes no significant differences were obtained for the studied traits except seed yield. Among and within ecotypes genotypic coefficient of variation indicated higher level of variation among ecotypes than within ecotypes. In both of the experiments, there was a large genetic variation for silybin and silymarin quality and quantity. Cluster analysis of 34 accessions was performed for morphological traits and silymarin and silybin characteristics, separately. The resulting dendrogram based on silybin and silymarin characteristics revealed that the native accessions such as Dezfoul, Fereydounkenar and Nour, had highest flavonolignans and they were better than the foreign varieties. Also, there was no clear relationship between clustering based on morphological traits and flavonolignan compounds.


Assuntos
Lignanas/isolamento & purificação , Cardo Mariano/genética , Análise por Conglomerados , Lignanas/química , Cardo Mariano/química
9.
Fitoterapia ; 76(2): 143-7, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15752622

RESUMO

Phenotypic and genotypic coefficient of variability, heritability in broad sense and genetic advance were determined investigating the characters of 15 accessions of Silybum marianum. Seed yield/plant and number of capsules/plant had highest estimates of genotypic variation, heritability and genetic advance which suggest that direct selection for these traits is suitable for the improvement of this crop. Number of capsules/plant had a significant positive correlation with the number of branches/plant and leaf length (r=0.3398, 0.7547), whereas seed yield/plant had a positive significant correlation with leaf length, stem diameter, capsule diameter and silymarin content (r=0.6830, 0.3140, 0.3484, 0.2925).


Assuntos
Variação Genética , Cardo Mariano/genética , Fitoterapia , Característica Quantitativa Herdável , Genótipo , Humanos
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