Masaji Koshioka

Nihon University, Edo, Tōkyō, Japan

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Publications (119)260.55 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: We aimed to identify the main compounds responsible for low temperature-induced yellow pigmentation of the bracts of Zantedeschia aethiopica 'Wedding March'. On the basis of the area ratios estimated from absorbance at 400 nm in HPLC analyses, we identified two flavonoids, isoorientin and swertiajaponin, as such compounds. We also identified two additional flavonoids, isovitexin and swertisin, which do not contribute considerably to the yellow pigmentation. Flavonoids of Zantedeschia bracts seem to belong to the class of flavone C-glycosides.
    Natural product communications 03/2015; 10(3):425-7. · 0.91 Impact Factor
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    ABSTRACT: Five anthocyanins, delphinidin 3-O-rutinoside, cyanidin 3-O-rutinoside, petunidin 3-O-rutinoside, malvidin 3-O-glucoside and malvidin 3-O-rutinoside, were identified. Three anthocyanins, delphinidin 3-O-glucoside, cyanidin 3-O-glucoside and pelargonidin 3-O-rutinoside, were putatively identified based on C18 HPLC retention time, absorption spectrum, including λmax, and comparisons with those of corresponding standard anthocyanins, as the compounds responsible for the pink to purple-red pigmentation of the bracts of Curcuma alismatifolia and five related species. Cluster analysis based on four major anthocyanins formed two clusters. One consisted of only one species, C. alismatifolia, and the other consisted of five. Each cluster further formed sub-clusters depending on either species or habitats.
    Natural product communications 03/2015; 10(3):453-6. · 0.91 Impact Factor
  • Horticultural Research (Japan) 01/2015; 14(3):267-272. DOI:10.2503/hrj.14.267
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    ABSTRACT: The gibberellin 2-oxidase catalyzes the bioactive gibberellins or their immediate precursors to inactive forms. We have previously produced transgenic plants of the liliaceous plant Tricyrtis sp. containing the GA2ox gene from the linderniaceous plant Torenia fournieri. These transgenic plants showed dwarf phenotypes as expected but unfortunately had no flowers or only small, unopened flowers. Recently, one newly produced transgenic line (G2-55) formed fully opened flowers. G2-55 showed a moderately dwarf phenotype and the shoot length decreased to 63.4% of that of the control, non-transgenic plants. No significant differences in the number of flowers per shoot and in the flower size were observed between G2-55 and the control. Flow cytometry analysis and chromosome observation showed that G2-55 was tetraploid (2n=4x=52), whereas the other transgenic lines producing no or only small flowers were diploid (2n=2x=26) as the mother plant. Pollen fertility of G2-55 was 81.2% as determined by acetocarmine staining. The tetraploidy in G2-55 might be resulted from somaclonal variation of embryogenic calluses used as a target material for Agrobacterium-mediated transformation. The tetraploid transgenic plant G2-55 may be useable not only directly as a potted plant, but also as a material for further breeding of Tricyrtis spp.
    Plant Biotechnology 01/2014; 31(4):335-340. DOI:10.5511/plantbiotechnology.14.0916a · 0.87 Impact Factor
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    ABSTRACT: Gibberellins (GAs) are the plant hormones that control many aspects of plant growth and development, including stem elongation. Genes encoding enzymes related to the GA biosynthetic and metabolic pathway have been isolated and characterized in many plant species. Gibberellin 2-oxidase (GA2ox) catalyzes bioactive GAs or their immediate precursors to inactive forms; therefore, playing a direct role in determining the levels of bioactive GAs. In the present study, we produced transgenic plants of the liliaceous monocotyledon Tricyrtis sp. overexpressing the GA2ox gene from the linderniaceous dicotyledon Torenia fournieri (TfGA2ox2). All six transgenic plants exhibited dwarf phenotypes, and they could be classified into two classes according to the degree of dwarfism: three plants were moderately dwarf and three were severely dwarf. All of the transgenic plants had small or no flowers, and smaller, rounder and darker green leaves. Quantitative real-time reverse transcription-polymerase chain reaction (PCR) analysis showed that the TfGA2ox2 expression level generally correlated with the degree of dwarfism. The endogenous levels of bioactive GAs, GA1 and GA4, largely decreased in transgenic plants as shown by liquid chromatography-mass spectrometry (LC-MS) analysis, and the level also correlated with the degree of dwarfism. Exogenous treatment of transgenic plants with gibberellic acid (GA3) resulted in an increased shoot length, indicating that the GA signaling pathway might normally function in transgenic plants. Thus, morphological changes in transgenic plants may result from a decrease in the endogenous levels of bioactive GAs. Finally, a possibility of molecular breeding for plant form alteration in liliaceous ornamental plants by genetically engineering the GA metabolic pathway is discussed.
    Journal of plant physiology 06/2013; 170(16). DOI:10.1016/j.jplph.2013.05.002 · 2.56 Impact Factor
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    ABSTRACT: In senescing carnation (Dianthus caryophyllus L.) flowers, ethylene production begins in the gynoecium, and the resulting ethylene acts on petals, inducing autocatalytic ethylene production. We investigated the role of abscisic acid (ABA) in ethylene production in the gynoecium of flowers. First, cDNAs of major genes involved in ABA biosynthesis and signaling were cloned from carnation flower tissues. Then, changes in ABA content and gene expression of ABA biosynthesis and signaling in the ovary were examined using three cultivars, ‘Light Pink Barbara (LPB)’ and ‘Excerea’, whose cut flowers produce ethylene during senescence and have an ordinary vase-life of about one week, and ‘Miracle Rouge’, whose cut flowers produce no detectable ethylene during senescence and have a vase-life of about three weeks. ABA content in the ovary was 530–710 pmol·g−1 fresh weight (FW) from Os 2 (early opening stage) to Os 6 (end of opening stage) in ‘LPB’, and at 200–380 pmol·g−1 FW in ‘Excerea’ at the same stages; but 930 pmol·g−1 FW at Ss 1 (early senescence stage). The ABA content remained at 70– 160 pmol·g−1 FW in ‘Miracle Rouge’. The changes in ABA content were in parallel with the transcript levels of DcNCED1 (carnation gene for 9-cis-epoxycarotenoid dioxygenase). DcPYR1 (ABA receptor gene) transcript was 0.004–0.007 relative expression level (r.e.l.) in ‘LPB’ ovary at Os 1–Os 3, and 0.028 r.e.l. at Ss 1 (beginning of senescence stage). In ‘Excerea’ ovary, DcPYR1 transcript was 0.025–0.037 r.e.l. during flower opening and higher at Ss 1. By contrast, DcPYR1 transcript remained at 0.002–0.006 r.e.l. in ‘Miracle Rouge’ ovary during flower opening and senescence. The transcripts of DcACS1, the key gene for ethylene biosynthesis, were detected at Ss 1 in ‘LPB’, and at Ss 2 in ‘Excerea’, but not in ‘Miracle Rouge’ throughout flower opening and senescence stages. These findings suggest that ABA plays a causal role in inducing the expression of the DcACS1 gene in the gynoecium, leading to ethylene biosynthesis, and that both the ABA content and DcPYR1 expression must be above putative threshold levels for ABA to exert its action.
    Journal- Japanese Society for Horticultural Science 01/2013; 82(3):242-254. DOI:10.2503/jjshs1.82.242 · 0.74 Impact Factor
  • Horticultural Research (Japan) 01/2013; 12(1):97-102. DOI:10.2503/hrj.12.97
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    ABSTRACT: Germination of Styrax japonicus seeds is promoted by warm stratification (WS) at 18–20°C followed by cold stratification (CS) at 4–5°. The objective of this work was to analyze the state and mobility of water molecules measured by 1H-NMR and endogenous gibberellins (GAs) and abscisic acid (ABA) by ultra performance liquid chromatography/mass spectrometry/mass spectrometry (UPLC-MS/MS) as influenced by WS and CS treatments had not previously been investigated. Styrax seeds that received 35 days of WS (35D WS) followed by 63 days of CS (63D CS) (35D WS + 63D CS) germinated. Seeds that received only 35D WS failed to germinate. Endogenous GA1, GA8, GA19, GA20, and GA53 were identified as well as GA17, GA23, GA28, GA29, and GA97 by gas chromatography/MS (GC/MS) and UPLC-MS/MS in seeds that were treated with warm and cold stratification (WS + CS). This suggests that the early C-13 hydroxylation pathway [-GA53-(GA44)-GA19-GA20-GA1-GA8] of GAs is a major biosynthetic pathway in the seeds. The concentration of GA53 and GA19 increased following WS and that of GA53 increased after WS + CS. The concentration of GA19 increased only slightly after WS + CS. The concentration of GA1 increased only after WS + CS. ABA concentration significantly decreased following the WS treatment. It is concluded that the mobility of water molecules and water content in cotyledons and endosperm is increased following WS + CS treatments. The occurrence of C-13 hydroxylated GAs suggests that the early C-13 hydroxylation pathway, → GA53 → GA44 → GA19 → GA20 → GA1 → GA8, is a major biosynthetic pathway in Styrax seeds. Additional key wordsgibberellin metabolism–mass spectrometry–mass spectrometry (UPLC-MS/MS)–ultra performance liquid chromatography–water mobility
    Horticulture, Environment and Biotechnology 06/2011; 52(3):233-239. DOI:10.1007/s13580-011-0207-4 · 0.73 Impact Factor
  • Horticultural Research (Japan) 01/2011; 10(3):389-393. DOI:10.2503/hrj.10.389
  • Horticultural Research (Japan) 01/2009; 8(2):175-180. DOI:10.2503/hrj.8.175
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    ABSTRACT: ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
    ChemInform 09/2008; 39(40). DOI:10.1002/chin.200840174
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    ABSTRACT: Three new 11β-hydroxy C20 gibberellins have been isolated from immature loquat fruit and their structures were established as 11β-hydroxy-GA12, 11β-hydroxy-GA15 and 11β-hydroxy-GA53, respectively, by direct GC–MS comparisons with authentic samples obtained from gibberellic acid by multistep syntheses. An advanced intermediate (30) was prepared in 20 steps from which 6 11β-hydroxy C20 gibberellins were prepared by parallel routes involving up to a further 5 steps for each sequence. The key steps involved a much improved synthesis of gibberellenic acid derivatives, a Lewis acid catalysed cyclisation of a diazoketone, a domino-hydroboration of a diene and oxidative cleavage of a ketone derived enolate.
    Tetrahedron 05/2008; 64(21):4835-4851. DOI:10.1016/j.tet.2008.01.131 · 2.64 Impact Factor
  • Horticultural Research (Japan) 01/2008; 7(2):277-281. DOI:10.2503/hrj.7.277
  • Horticultural Research (Japan) 01/2007; 6(4):591-596. DOI:10.2503/hrj.6.591
  • Horticultural Research (Japan) 01/2007; 6(2):271-275. DOI:10.2503/hrj.6.271
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    ABSTRACT: Immature pumpkin (Cucurbita maxima) seeds contain gibberellin (GA) oxidases with unique catalytic properties resulting in GAs of unknown function for plant growth and development. Overexpression of pumpkin GA 7-oxidase (CmGA7ox) in Arabidopsis (Arabidopsis thaliana) resulted in seedlings with elongated roots, taller plants that flower earlier with only a little increase in bioactive GA4 levels compared to control plants. In the same way, overexpression of the pumpkin GA 3-oxidase1 (CmGA3ox1) resulted in a GA overdose phenotype with increased levels of endogenous GA4. This indicates that, in Arabidopsis, 7-oxidation and 3-oxidation are rate-limiting steps in GA plant hormone biosynthesis that control plant development. With an opposite effect, overexpression of pumpkin seed-specific GA 20-oxidase1 (CmGA20ox1) in Arabidopsis resulted in dwarfed plants that flower late with reduced levels of GA4 and increased levels of physiological inactive GA17 and GA25 and unexpected GA34 levels. Severe dwarfed plants were obtained by overexpression of the pumpkin GA 2-oxidase1 (CmGA2ox1) in Arabidopsis. This dramatic change in phenotype was accompanied by a considerable decrease in the levels of bioactive GA4 and an increase in the corresponding inactivation product GA34 in comparison to control plants. In this study, we demonstrate the potential of four pumpkin GA oxidase-encoding genes to modulate the GA plant hormone pool and alter plant stature and development.
    Plant physiology 03/2006; 140(2):528-36. DOI:10.1104/pp.105.073668 · 6.84 Impact Factor
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    ABSTRACT: A bright-red colored grape cultivar 'Aki Queen' (Vitis labruscana Bailey) frequently expresses deep color and bears dark-red berries. The typically colored berries are distributed in the range from red to orange hue angle values, while the deep colored berries are distributed in the range from red to purple hue angle values. The deep colored berries tended to contain more than 50 × 10 -6 g·cm -2 total anthocyanin contents in the skin, and these contents were higher than those of the typically colored berries. Increase of the total anthocyanin content results in the deep coloration. Among thirteen kinds of anthocyanins identified, peonidin- and cyanidin-type anthocyanins were predominant, as well as malvidin- and petunidin-type anthocyanins, in both colored berries. Composition ratios of malvidin- and petunidin-type anthocyanins increased, and those of peonidin- and cyanidin-type anthocyanins decreased, in the deep colored berries. These composition changes also seem to cause the deep coloration as well as the increase in total pigment content. We could not find co-pigmentation effects of flavonols on the deep coloration.
    Engei Gakkai zasshi 09/2005; 74(5):401-406. DOI:10.2503/jjshs.74.401
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    ABSTRACT: Long day (LD) exposure of rosette plants causes rapid stem/petiole elongation, a more vertical growth habit, and flowering; all changes are suggestive of a role for the gibberellin (GA) plant growth regulators. For Arabidopsis (Arabidopsis thaliana) L. (Heynh), we show that enhancement of petiole elongation by a far-red (FR)-rich LD is mimicked by a brief (10 min) end-of-day (EOD) FR exposure in short day (SD). The EOD response shows red (R)/FR photoreversibility and is not affected in a phytochrome (PHY) A mutant so it is mediated by PHYB and related PHYs. FR photoconversion of PHYB to an inactive form activates a signaling pathway, leading to increased GA biosynthesis. Of 10 GA biosynthetic genes, expression of the 20-oxidase, AtGA20ox2, responded most to FR (up to a 40-fold increase within 3 h). AtGA20ox1 also responded but to a lesser extent. Stimulation of petiole elongation by EOD FR is reduced in a transgenic AtGA20ox2 hairpin gene silencing line. By contrast, it was only in SD that a T-DNA insertional mutant of AtGA20ox1 (ga5-3) showed reduced response. Circadian entrainment to a daytime pattern provides an explanation for the SD expression of AtGA20ox1. Conversely, the strong EOD/LD FR responses of AtGA20ox2 may reflect its independence of circadian regulation. While FR acting via PHYB increases expression of AtGA20ox2, other GA biosynthetic genes are known to respond to R rather than FR light and/or to other PHYs. Thus, there must be different signal transduction pathways, one at least showing a positive response to active PHYB and another showing a negative response.
    Plant physiology 07/2005; 138(2):1106-16. DOI:10.1104/pp.104.059055 · 6.84 Impact Factor
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    ABSTRACT: Flower pigmentation is one of the most important traits for ornamental plants. To clarify the genetic basis for carotenoid pigmentation in flower tepals of Asiatic hybrid lily (Lilium sp.), we evaluated the segregation of a tepal-carotenoid content among F1 plants derived from a cross between ‘Montreux’ (having a small amount of carotenoids) and ‘Connecticut King’ (having a large amount of carotenoids), and mapped genetic loci for the carotenoid pigmentation onto the molecular linkage maps of ‘Montreux’ and ‘Connecticut King’ that we constructed previously. The tepal-carotenoid content among the F1 plants showed continuous segregation, indicating that several genes are associated with this trait. Quantitative trait loci (QTL) analysis identified one QTL, qCARmon6, on the sixth linkage group of the ‘Montreux’ map. qCARmon6 explained 58.2% of the total phenotypic variation, that is, this locus had a large effect on the carotenoid accumulation. The result that qCARmon6 was mapped on the linkage group of ‘Montreux’ which has a small amount of carotenoid pigments in tepals indicates that this locus has a dominant negative effect on carotenoid pigmentation.
    Scientia Horticulturae 03/2005; 104(1-104):57-64. DOI:10.1016/j.scienta.2004.08.007 · 1.37 Impact Factor
  • Horticultural Research (Japan) 01/2005; 4(3):343-346. DOI:10.2503/hrj.4.343

Publication Stats

2k Citations
260.55 Total Impact Points


  • 2008–2014
    • Nihon University
      • • College of Bioresource Sciences
      • • Department of Plant Science and Resources
      Edo, Tōkyō, Japan
  • 2002–2004
    • The Graduate University for Advanced Studies
      Миура, Kanagawa, Japan
  • 1999
    • Minami Kyushu University
      Миядзаки, Miyazaki, Japan
  • 1998
    • National Engineering Research Center for Vegetables
      Peping, Beijing, China
  • 1997
    • Japan Research Institute
      Hokodate, Hokkaidō, Japan
  • 1993–1997
    • Agriculture, Forestry and Fisheries Research Council
      Tsukuba, Ibaraki, Japan
  • 1988–1995
    • Australian National University
      Canberra, Australian Capital Territory, Australia
  • 1987–1989
    • National Institute for Agro-Environmental Sciences in Japan
      Tsukuba, Ibaraki, Japan
  • 1985–1987
    • The University of Calgary
      • Department of Biological Sciences
      Calgary, Alberta, Canada
    • University of Adelaide
      Tarndarnya, South Australia, Australia