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Masahiro Nishihara - One of the best experts on this subject based on the ideXlab platform.
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biological effects of ion beam irradiation on perennial Gentian and apple
Plant Biotechnology, 2018Co-Authors: Nobuhiro Sasaki, Nobue Hoshi, Aiko Watanabe, Tomonori Asakawa, Makoto Sasaki, Zenbi Naito, Yoshiya Furusawa, Takashi Shimokawa, Masahiro NishiharaAbstract:The development of new varieties of perennial plants generally requires lengthy and laborious procedures. In this study, we used ion beam irradiation mutagenesis in an attempt to accelerate the breeding process for perennial plants. We evaluated the biological effects of five ion beam sources (carbon, neon, argon, silicon, and iron) and neutron irradiation on Japanese Gentian and apple. These treatments were applied at the National Institute of Radiological Sciences (NIRS) using the Heavy Ion Medical Accelerator in Chiba (HIMAC) and the Neutron-exposure Accelerator System for Biological Effect Experiments (NASBEE). Biological effects were observed in in vitro Gentian plants after irradiation with ion beams at <10 Gy, whereas apple trees were less sensitive to ion beam irradiation. The growth of Gentians in vitro was repressed by 3 Gy neutron irradiation, while that of grafted apple trees was not affected by 4 Gy neutron irradiation. During in vitro proliferation, seven pink-flowered lines were obtained from originally blue-flowered Gentian after C and Ne ion beam irradiation treatments. Genomic and reverse transcription-PCR analyses of these lines suggested that the mutations occurred in the genomic region containing F3'5'H (encoding flavonoid 3',5'-hydroxylase). These results provide useful information for the mutagenesis and breeding of Gentian, apple, and other perennial plants.
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development of basic technologies for improvement of breeding and cultivation of japanese Gentian
Breeding Science, 2018Co-Authors: Masahiro Nishihara, Nobuhiro Sasaki, Keisuke Tasaki, Hideyuki TakahashiAbstract:Abstract Japanese Gentians are the most important ornamental flowers in Iwate Prefecture and their breeding and cultivation have been actively conducted for half a century. With its cool climate and large hilly and mountainous area, more than 60% of Gentian production in Japan occurs in Iwate Prefecture. Recent advances in Gentian breeding and cultivation have facilitated the efficient breeding of new cultivars; disease control and improved cultivation conditions have led to the stable production of Japanese Gentians. Molecular biology techniques have been developed and applied in Gentian breeding, including the diagnosis of viral diseases and analysis of physiological disorders to improve Gentian production. This review summarizes such recent approaches that will assist in the development of new cultivars and support cultivation. More recently, new plant breeding techniques, including several new biotechnological methods such as genome editing and viral vectors, have also been developed in Gentian. We, therefore, present examples of their application to Gentians and discuss their advantages in future studies of Gentians.
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identification of the glucosyltransferase that mediates direct flavone c glucosylation in Gentiana triflora
FEBS Letters, 2015Co-Authors: Nobuhiro Sasaki, Takashi Nakatsuka, Yuzo Nishizaki, Eri Yamada, Fumi Tatsuzawa, Hideyuki Takahashi, Masahiro NishiharaAbstract:The major flavonoids accumulated in leaves of Japanese Gentian (Gentiana triflora) were determined as isoorientin (luteolin 6-C-glucoside) and isoorientin 4′-glucoside. A cDNA (GtUF6CGT1) was isolated that encoded the UDP-glucose-dependent glucosyltransferase that is involved in C-glycosylflavone biosynthesis. The recombinant GtUF6CGT1 protein could transfer a glucose group to the C6 position of a flavone skeleton through C-linkage, using UDP-glucose as the glucosyl donor. These C-glycosylflavones also accumulated in petals. A good correlation was observed between GtUF6CGT1 expression and C-glycosylflavone accumulation in leaves and petals. GtUF6CGT1 is the first reported C-glucosyltransferase that mediates direct C-glucosylation of the flavone skeleton.
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the gentio oligosaccharide gentiobiose functions in the modulation of bud dormancy in the herbaceous perennial Gentiana
The Plant Cell, 2014Co-Authors: Hideyuki Takahashi, Masahiro Nishihara, Tomohiro Imamura, Naotake Konno, Takumi Takeda, Teruko Konishi, Kohei Fujita, Hirofumi UchimiyaAbstract:Bud dormancy is an adaptive strategy that perennials use to survive unfavorable conditions. Gentians (Gentiana), popular alpine flowers and ornamentals, produce overwintering buds (OWBs) that can persist through the winter, but the mechanisms regulating dormancy are currently unclear. In this study, we conducted targeted metabolome analysis to obtain clues about the metabolic mechanisms involved in regulating OWB dormancy. Multivariate analysis of metabolite profiles revealed metabolite patterns characteristic of dormant states. The concentrations of gentiobiose [β-d-Glcp-(1→6)-d-Glc] and Gentianose [β-d-Glcp-(1→6)-d-Glc-(1→2)-d-Fru] significantly varied depending on the stage of OWB dormancy, and the gentiobiose concentration increased prior to budbreak. Both activation of invertase and inactivation of β-glucosidase resulted in gentiobiose accumulation in ecodormant OWBs, suggesting that gentiobiose is seldom used as an energy source but is involved in signaling pathways. Furthermore, treatment with exogenous gentiobiose induced budbreak in OWBs cultured in vitro, with increased concentrations of sulfur-containing amino acids, GSH, and ascorbate (AsA), as well as increased expression levels of the corresponding genes. Inhibition of GSH synthesis suppressed gentiobiose-induced budbreak accompanied by decreases in GSH and AsA concentrations and redox status. These results indicate that gentiobiose, a rare disaccharide, acts as a signal for dormancy release of Gentian OWBs through the AsA-GSH cycle.
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heterologous expression of Gentian myb1r transcription factors suppresses anthocyanin pigmentation in tobacco flowers
Plant Cell Reports, 2013Co-Authors: Takashi Nakatsuka, Eri Yamada, Kohei Fujita, Misa Saito, Masahiro NishiharaAbstract:Single-repeat MYB transcription factors, GtMYB1R1 and GtMYB1R9 , were isolated from Gentian. Overexpression of these genes reduced anthocyanin accumulation in tobacco flowers, demonstrating their applicability to modification of flower color. RNA interference (RNAi) has recently been used to successfully modify flower color intensity in several plant species. In most floricultural plants, this technique requires prior isolation of target flavonoid biosynthetic genes from the same or closely related species. To overcome this limitation, we developed a simple and efficient method for reducing floral anthocyanin accumulation based on genetic engineering using novel transcription factor genes isolated from Japanese Gentians. We identified two single-repeat MYB genes—GtMYB1R and GtMYB1R9—predominantly expressed in Gentian petals. Transgenic tobacco plants expressing these genes were produced, and their flowers were analyzed for flavonoid components and expression of flavonoid biosynthetic genes. Transgenic tobacco plants expressing GtMYB1R1 or GtMYB1R9 exhibited significant reductions in floral anthocyanin accumulation, resulting in white-flowered phenotypes. Expression levels of chalcone isomerase (CHI), dihydroflavonol 4-reductase (DFR), and anthocyanidin synthase (ANS) genes were preferentially suppressed in these transgenic tobacco flowers. A yeast two-hybrid assay demonstrated that both GtMYB1R1 and GtMYB1R9 proteins interacted with the GtbHLH1 protein, previously identified as an anthocyanin biosynthesis regulator in Gentian flowers. In addition, a transient expression assay indicated that activation of the Gentian GtDFR promoter by the GtMYB3-GtbHLH1 complex was partly canceled by addition of GtMYB1R1 or GtMYB1R9. These results suggest that GtMYB1R1 and GtMYB1R9 act as antagonistic transcription factors of anthocyanin biosynthesis in Gentian flowers. These genes should consequently be useful for manipulating anthocyanin accumulation via genetic engineering in flowers of other floricultural plant species.
Hideyuki Takahashi - One of the best experts on this subject based on the ideXlab platform.
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development of basic technologies for improvement of breeding and cultivation of japanese Gentian
Breeding Science, 2018Co-Authors: Masahiro Nishihara, Nobuhiro Sasaki, Keisuke Tasaki, Hideyuki TakahashiAbstract:Abstract Japanese Gentians are the most important ornamental flowers in Iwate Prefecture and their breeding and cultivation have been actively conducted for half a century. With its cool climate and large hilly and mountainous area, more than 60% of Gentian production in Japan occurs in Iwate Prefecture. Recent advances in Gentian breeding and cultivation have facilitated the efficient breeding of new cultivars; disease control and improved cultivation conditions have led to the stable production of Japanese Gentians. Molecular biology techniques have been developed and applied in Gentian breeding, including the diagnosis of viral diseases and analysis of physiological disorders to improve Gentian production. This review summarizes such recent approaches that will assist in the development of new cultivars and support cultivation. More recently, new plant breeding techniques, including several new biotechnological methods such as genome editing and viral vectors, have also been developed in Gentian. We, therefore, present examples of their application to Gentians and discuss their advantages in future studies of Gentians.
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and Trails for Access
2016Co-Authors: Hidetoshi Yamada, Sayaka Kikuchi, Tomoki Inui, Hideyuki TakahashiAbstract:Background: Gentian roots have been used as a herbal medicine because of their anti-inflammatory activities. However, the molecular mechanisms of these anti-inflammatory effects remain to be completely explained. Methods and Findings: Here, we investigated anti-inflammatory effects of Gentian roots and showed that root extracts from Gentiana triflora inhibited lipopolysaccharide (LPS)-induced expression of TNF-a in RAW264.7 cells. The extracts also contained swertiamarin and gentiopicroside, which are the major active compounds of Gentian roots; however, neither compound had any effect on LPS-induced TNF-a production in our test system. We isolated gentiolactone as an inhibitor of TNF-a production from the extracts. Gentiolactone also inhibited LPS-induced inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (Cox-2) expression at the mRNA level. Moreover, gentiolactone suppressed NF-kB transcriptional activity without inhibition of IkB degradation or NF-kB nuclear transport. Conclusions: Our results indicate that inhibition of TNF-a, iNOS and Cox-2 expression by gentiolactone is one of the mechanisms of the anti-inflammatory properties of Gentian roots
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characterization of spermidine synthase and spermine synthase the polyamine synthetic enzymes that induce early flowering in Gentiana triflora
Biochemical and Biophysical Research Communications, 2015Co-Authors: Tomohiro Imamura, Atsumi Higuchi, Kohei Fujita, Keisuke Tasaki, Hideyuki TakahashiAbstract:Polyamines are essential for several living processes in plants. However, regulatory mechanisms of polyamines in herbaceous perennial are almost unknown. Here, we identified homologs of two Arabidopsis polyamine-synthetic enzymes, spermidine synthase (SPDS) and spermine synthase (SPMS) denoted as GtSPDS and GtSPMS, from the Gentian plant, Gentiana triflora. Our results showed that recombinant proteins of GtSPDS and GtSPMS possessed SPDS and SPMS activities, respectively. The expression levels of GtSPDS and GtSPMS increased transiently during vegetative to reproductive growth phase and overexpression of the genes hastened flowering, suggesting that these genes are involved in flowering induction in Gentian plants.
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identification of the glucosyltransferase that mediates direct flavone c glucosylation in Gentiana triflora
FEBS Letters, 2015Co-Authors: Nobuhiro Sasaki, Takashi Nakatsuka, Yuzo Nishizaki, Eri Yamada, Fumi Tatsuzawa, Hideyuki Takahashi, Masahiro NishiharaAbstract:The major flavonoids accumulated in leaves of Japanese Gentian (Gentiana triflora) were determined as isoorientin (luteolin 6-C-glucoside) and isoorientin 4′-glucoside. A cDNA (GtUF6CGT1) was isolated that encoded the UDP-glucose-dependent glucosyltransferase that is involved in C-glycosylflavone biosynthesis. The recombinant GtUF6CGT1 protein could transfer a glucose group to the C6 position of a flavone skeleton through C-linkage, using UDP-glucose as the glucosyl donor. These C-glycosylflavones also accumulated in petals. A good correlation was observed between GtUF6CGT1 expression and C-glycosylflavone accumulation in leaves and petals. GtUF6CGT1 is the first reported C-glucosyltransferase that mediates direct C-glucosylation of the flavone skeleton.
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gentiolactone a secoiridoid dilactone from Gentiana triflora inhibits tnf α inos and cox 2 mrna expression and blocks nf κb promoter activity in murine macrophages
PLOS ONE, 2014Co-Authors: Hidetoshi Yamada, Sayaka Kikuchi, Tomoki Inui, Hideyuki Takahashi, Kenichi KimuraAbstract:Background Gentian roots have been used as a herbal medicine because of their anti-inflammatory activities. However, the molecular mechanisms of these anti-inflammatory effects remain to be completely explained. Methods and Findings Here, we investigated anti-inflammatory effects of Gentian roots and showed that root extracts from Gentiana triflora inhibited lipopolysaccharide (LPS)-induced expression of TNF-α in RAW264.7 cells. The extracts also contained swertiamarin and gentiopicroside, which are the major active compounds of Gentian roots; however, neither compound had any effect on LPS-induced TNF-α production in our test system. We isolated gentiolactone as an inhibitor of TNF-α production from the extracts. Gentiolactone also inhibited LPS-induced inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (Cox-2) expression at the mRNA level. Moreover, gentiolactone suppressed NF-κB transcriptional activity without inhibition of IκB degradation or NF-κB nuclear transport. Conclusions Our results indicate that inhibition of TNF-α, iNOS and Cox-2 expression by gentiolactone is one of the mechanisms of the anti-inflammatory properties of Gentian roots.
Miran Brvar - One of the best experts on this subject based on the ideXlab platform.
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accidental poisoning with veratrum album mistaken for wild garlic allium ursinum
Clinical Toxicology, 2010Co-Authors: Irene Gilotta, Miran BrvarAbstract:Introduction. Veratrum album (white or false hellebore) is a poisonous plant containing steroidal alkaloids that cause nausea, vomiting, headache, visual disturbances, paresthesia, dizziness, bradycardia, atrioventricular block, hypotension, and syncope. It is regularly mistaken for Gentiana lutea (yellow Gentian). We report accidental poisoning with V. album mistaken for Allium ursinum (wild garlic), a wild plant used in soups and salads in Central Europe. Case series. Four adults (24–45 years) accidentally ingested V. album mistaken for A. ursinum in self-prepared salads and soups. Within 15–30 min of ingestion they developed nausea, vomiting, and abdominal pain. At the same time dizziness, tingling, dimmed and jumping vision, transient blindness, and confusion appeared. On arrival at the ED, all patients had sinus bradycardia and hypotension. Following treatment the patients were discharged well 24–48 h after ingestion. Conclusion. In patients presenting with gastrointestinal, neurological, and cardiov...
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accidental poisoning with veratrum album mistaken for wild garlic allium ursinum
Clinical Toxicology, 2010Co-Authors: Irene Gilotta, Miran BrvarAbstract:Introduction. Veratrum album (white or false hellebore) is a poisonous plant containing steroidal alkaloids that cause nausea, vomiting, headache, visual disturbances, paresthesia, dizziness, bradycardia, atrioventricular block, hypotension, and syncope. It is regularly mistaken for Gentiana lutea (yellow Gentian). We report accidental poisoning with V. album mistaken for Allium ursinum (wild garlic), a wild plant used in soups and salads in Central Europe. Case series. Four adults (24–45 years) accidentally ingested V. album mistaken for A. ursinum in self-prepared salads and soups. Within 15–30 min of ingestion they developed nausea, vomiting, and abdominal pain. At the same time dizziness, tingling, dimmed and jumping vision, transient blindness, and confusion appeared. On arrival at the ED, all patients had sinus bradycardia and hypotension. Following treatment the patients were discharged well 24–48 h after ingestion. Conclusion. In patients presenting with gastrointestinal, neurological, and cardiov...
Guoyong Li - One of the best experts on this subject based on the ideXlab platform.
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shifting phenology and abundance under experimental warming alters trophic relationships and plant reproductive capacity
Ecology, 2011Co-Authors: Peter B Reich, Guoyong LiAbstract:Phenological mismatches due to climate change may have important ecological consequences. In a three-year study, phenological shifts due to experimental warming markedly altered trophic relationships between plants and insect herbivores, causing a dramatic decline of reproductive capacity for one of the plant species. In a Tibetan meadow, the Gentian (Gentiana formosa) typically flowers after the peak larva density of a noctuid moth (Melanchra pisi) that primarily feeds on a dominant forb (anemone, Anemone trullifolia var. linearis). However, artificial warming of ∼1.5°C advanced Gentian flower phenology and anemone vegetative phenology by a week, but delayed moth larvae emergence by two weeks. The warming increased larval density 10-fold, but decreased anemone density by 30%. The phenological and density shifts under warmed conditions resulted in the insect larvae feeding substantially on the Gentian flowers and ovules; there was ∼100-fold more damage in warmed than in unwarmed chambers. This radically increased trophic connection reduced Gentian plant reproduction and likely contributed to its reduced abundance in the warmed chambers.
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petal color flower temperature and behavior in an alpine annual herb Gentiana leucomelaena Gentianaceae
Arctic Antarctic and Alpine Research, 2010Co-Authors: Junpeng Mu, Guoyong LiAbstract:Abstract Gentiana leucomelaena (Gentianaceae), an alpine herbaceous species of the Qinghai-Tibetan Plateau, has two colors of flowers (blue and white) that bloom in early spring. In order to determine the effect of petal color on flower interior temperature and behavior in the Gentian, we investigated the differences in timing of flower opening and closure and the interior temperature of blooming flowers between the two colors, while recording the ambient temperature, light intensity, and relative humidity over the flowering season from March to May of 2009. When the flowers were open, the anther temperature was higher in the white flowers than in the blue flowers in various weather patterns; in particular it was about 2 °C higher on sunny days. Relative to the ambient temperature, the anther temperature was 1.27 °C higher in the white flowers, but was 0.41 °C lower in the blue flowers. Compared to blue flowers, white flowers opened later but closed earlier in the day at a higher ambient temperature. The ...
Takashi Nakatsuka - One of the best experts on this subject based on the ideXlab platform.
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identification of the glucosyltransferase that mediates direct flavone c glucosylation in Gentiana triflora
FEBS Letters, 2015Co-Authors: Nobuhiro Sasaki, Takashi Nakatsuka, Yuzo Nishizaki, Eri Yamada, Fumi Tatsuzawa, Hideyuki Takahashi, Masahiro NishiharaAbstract:The major flavonoids accumulated in leaves of Japanese Gentian (Gentiana triflora) were determined as isoorientin (luteolin 6-C-glucoside) and isoorientin 4′-glucoside. A cDNA (GtUF6CGT1) was isolated that encoded the UDP-glucose-dependent glucosyltransferase that is involved in C-glycosylflavone biosynthesis. The recombinant GtUF6CGT1 protein could transfer a glucose group to the C6 position of a flavone skeleton through C-linkage, using UDP-glucose as the glucosyl donor. These C-glycosylflavones also accumulated in petals. A good correlation was observed between GtUF6CGT1 expression and C-glycosylflavone accumulation in leaves and petals. GtUF6CGT1 is the first reported C-glucosyltransferase that mediates direct C-glucosylation of the flavone skeleton.
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heterologous expression of Gentian myb1r transcription factors suppresses anthocyanin pigmentation in tobacco flowers
Plant Cell Reports, 2013Co-Authors: Takashi Nakatsuka, Eri Yamada, Kohei Fujita, Misa Saito, Masahiro NishiharaAbstract:Single-repeat MYB transcription factors, GtMYB1R1 and GtMYB1R9 , were isolated from Gentian. Overexpression of these genes reduced anthocyanin accumulation in tobacco flowers, demonstrating their applicability to modification of flower color. RNA interference (RNAi) has recently been used to successfully modify flower color intensity in several plant species. In most floricultural plants, this technique requires prior isolation of target flavonoid biosynthetic genes from the same or closely related species. To overcome this limitation, we developed a simple and efficient method for reducing floral anthocyanin accumulation based on genetic engineering using novel transcription factor genes isolated from Japanese Gentians. We identified two single-repeat MYB genes—GtMYB1R and GtMYB1R9—predominantly expressed in Gentian petals. Transgenic tobacco plants expressing these genes were produced, and their flowers were analyzed for flavonoid components and expression of flavonoid biosynthetic genes. Transgenic tobacco plants expressing GtMYB1R1 or GtMYB1R9 exhibited significant reductions in floral anthocyanin accumulation, resulting in white-flowered phenotypes. Expression levels of chalcone isomerase (CHI), dihydroflavonol 4-reductase (DFR), and anthocyanidin synthase (ANS) genes were preferentially suppressed in these transgenic tobacco flowers. A yeast two-hybrid assay demonstrated that both GtMYB1R1 and GtMYB1R9 proteins interacted with the GtbHLH1 protein, previously identified as an anthocyanin biosynthesis regulator in Gentian flowers. In addition, a transient expression assay indicated that activation of the Gentian GtDFR promoter by the GtMYB3-GtbHLH1 complex was partly canceled by addition of GtMYB1R1 or GtMYB1R9. These results suggest that GtMYB1R1 and GtMYB1R9 act as antagonistic transcription factors of anthocyanin biosynthesis in Gentian flowers. These genes should consequently be useful for manipulating anthocyanin accumulation via genetic engineering in flowers of other floricultural plant species.
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the Gentian orthologs of the ft tfl1 gene family control floral initiation in Gentiana
Plant and Cell Physiology, 2011Co-Authors: Tomohiro Imamura, Takashi Nakatsuka, Masahiro Nishihara, Atsumi Higuchi, Hideyuki TakahashiAbstract:Gentians are herbaceous perennials blooming in summer through autumn. Although they are popular ornamental flowers in Japan, the regulation of their timing of flowering has not been studied. We identified and characterized Gentian orthologs of the Arabidopsis FT/TFL1 gene family to elucidate the mechanisms of flowering initiation. We isolated three Gentian orthologs of FT and TFL1, denoted GtFT1, GtFT2 and GtTFL1. Since up-regulation of GtFT1 and GtFT2 as well as down-regulation of GtTFL1 promoted floral initiation in Gentian plantlets, these genes affected floral initiation in a similar way to Arabidopsis FT and TFL1. The expression levels of GtFT1 and GtFT2 in leaves of late-flowering Gentian increased prior to floral initiation, whereas GtTFL1 was highly expressed in shoot apical meristem at the vegetative stage and decreased drastically just before flowering initiation. Comparison of gene expression patterns showed that GtFT1 expression increased earlier in early-flowering than in late-flowering Gentian, whereas the timing of the increase in GtFT2 expression was similar in early- and late-flowering plants. The GtTFL1 expression in early-flowering Gentian was extremely low throughout the vegetative and reproductive stages. These results indicated that either the up-regulation of GtFT1 or the down-regulation of GtTFL1 may determine flowering time. Furthermore, we found that early-flowering but not late-flowering Gentians have a 320 bp insertion in the promoter region of GtTFL1. Thus, the negligible expression of GtTFL1 in early-flowering lines may be due to this insertion, resulting in a shortened vegetative stage.
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strict de novo methylation of the 35s enhancer sequence in Gentian
PLOS ONE, 2010Co-Authors: Keiichiro Mishiba, Takashi Nakatsuka, Yoshiko Abe, Satoshi Yamasaki, Hiroyuki Daimon, Masayuki Oda, Masahiro NishiharaAbstract:A novel transgene silencing phenomenon was found in the ornamental plant, Gentian (Gentiana triflora × G. scabra), in which the introduced Cauliflower mosaic virus (CaMV) 35S promoter region was strictly methylated, irrespective of the transgene copy number and integrated loci. Transgenic tobacco having the same vector did not show the silencing behavior. Not only unmodified, but also modified 35S promoters containing a 35S enhancer sequence were found to be highly methylated in the single copy transgenic Gentian lines. The 35S core promoter (−90)-introduced transgenic lines showed a small degree of methylation, implying that the 35S enhancer sequence was involved in the methylation machinery. The rigorous silencing phenomenon enabled us to analyze methylation in a number of the transgenic lines in parallel, which led to the discovery of a consensus target region for de novo methylation, which comprised an asymmetric cytosine (CpHpH; H is A, C or T) sequence. Consequently, distinct footprints of de novo methylation were detected in each (modified) 35S promoter sequence, and the enhancer region (−148 to −85) was identified as a crucial target for de novo methylation. Electrophoretic mobility shift assay (EMSA) showed that complexes formed in Gentian nuclear extract with the −149 to −124 and −107 to −83 region probes were distinct from those of tobacco nuclear extracts, suggesting that the complexes might contribute to de novo methylation. Our results provide insights into the phenomenon of sequence- and species- specific gene silencing in higher plants.
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metabolite profiling by capillary electrophoresis mass spectrometry reveals aberrant putrescine accumulation associated with idiopathic symptoms of Gentian plants
Journal of Horticultural Science & Biotechnology, 2009Co-Authors: Hideyuki Takahashi, Takashi Nakatsuka, Masahiro Nishihara, I Munemura, Hirofumi UchimiyaAbstract:SummaryThe disease, yellow dwarf-like symptom (YDS), in Gentians has the characteristics of leaf etiolation, gall formation, and shortening of the stem internodes. This disease leads to plant death, and has thus become a serious problem in commercial Gentian production. Despite intensive pathological investigation, the aetiology of the disease remains unclear. To increase our knowledge about YDS, we conducted metabolome analysis using capillary electrophoresis-mass spectrometry. Quantification of the metabolites in YDS-affected tissues showed that YDS particularly affected arginine-derived metabolites, including arginine, ornithine, citrulline, and putrescine. The concentration of putrescine increased 83-fold, and was accompanied by increased expression of the arginine decarboxylase gene. Thus putrescine synthesis and its accumulation appear to be the key metabolic changes associated with YDS in Gentians.