Tomokazu Koshiba

Tokyo Metropolitan University, Edo, Tōkyō, Japan

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Publications (92)421.67 Total impact

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  • Ken Yokawa, Tomokazu Koshiba, František Baluška
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    ABSTRACT: Auxin, indole-3-acetic acid (IAA), plays a crucial role for morphogenesis, development, growth, and tropisms in many plant species. Many studies have been investigating that auxin is biosynthesized via specific pathways depending on several enzymes started from amino acid, tryptophan. The particular region of auxin biosynthesis in maize was identified at the tip of coleoptile expressing abundant YUCCA (YUC) protein, which is essential for auxin synthesis. However, it is still mystery whether auxin biosynthesis is dependent on only such enzymes or not. In vitro experiment demonstrated that precursor of auxin molecule; indole-3-acetaldehyde (IAAld) was generated by light illumination of the mixture of tryptophan and flavin compounds in non-enzymatic manner. In addition, we have detected immediate production of reactive oxygen species (ROS) in illuminated Arabidopsis root cells. In this perspective, we are proposing the non-enzymatic regulation of redox homeostasis and auxin biosynthesis throughout the plant body under variable environmental light conditions.
    Plant signaling & behavior 06/2014; 9.
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    ABSTRACT: ZmPHOT1 and ZmPHOT2 are expressed differentially in maize coleoptiles and leaves, with Zmphot1 possibly involved in first-positive phototropic curvature of red-light-adapted maize coleoptiles exposed to pulsed low-fluence blue light. Unilateral blue-light perception by phototropin(s) is the first event of phototropism, with the subsequent signal causing lateral transport of auxin at the coleoptile tip region of monocots. In this study, we analyzed the behavior of two maize phototropin genes: ZmPHOT1 and ZmPHOT2, the latter identified from the maize genome database and newly characterized. Quantitative real-time PCR analysis demonstrated that ZmPHOT1 was abundantly expressed in etiolated coleoptiles, while lower expressions of both ZmPHOT1 and ZmPHOT2 were observed in young leaves. Interestingly, these genes were not specifically expressed in the coleoptile tip region, a key position for photoperception in phototropism. Exposure to pulsed low-fluence blue light (LBL) (0.33 µmol m(-2) s(-1) × 8 s) and continuous high-fluence blue light (HBL) (10 µmol m(-2) s(-1)) rapidly decreased ZmPHOT1 gene expression in coleoptiles, with levels of ZmPHOT2 not significantly altered in that tissue. In young leaves, no drastic expression changes were induced in either ZmPHOT1 or ZmPHOT2 by LBL or HBL irradiation. The Zmphot1 protein was investigated by Western blot analysis with anti-Osphot1 antibodies. Zmphot1 was detected in microsomal fractions, with higher levels in coleoptiles than in leaves. HBL caused rapid phosphorylation of the protein, whereas no phot1 phosphorylation was induced by LBL. The involvement of Zmphot1 in LBL-induced phototropic curvature of maize coleoptiles is discussed.
    Planta 05/2014; · 3.38 Impact Factor
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    ABSTRACT: Studies using inhibitors of indole-3-acetic acid (IAA) transport, not only for efflux but influx carriers, provide many aspects of auxin physiology in plants. 1-Naphtoxyacetic acid (1-NOA), an analog of the synthetic auxin 1-N-naphtalene acetic acid (NAA), inhibits the IAA influx carrier AUX1. However, 1-NOA also shows auxin activity because of its structural similarity to NAA. In this study, we have identified another candidate inhibitor of the IAA influx carrier. The compound, "7-B3; ethyl 2-[(2-chloro-4-nitrophenyl)thio]acetate," is a 2,4-dichlorophenoxyacetic acid (2,4-D) analog. At high concentrations (> 300 µM), 7-B3 slightly reduced IAA transport and tropic curvature of maize coleoptiles, whereas lower concentrations had almost no effect. We have analyzed the effects of 7-B3 on Arabidopsis thaliana seedlings. 7-B3 rescued the 2,4-D-inhibited root elongation, but not the NAA-inhibited root elongation. The effect of 7-B3 was weaker than that of 1-NOA. Both 1-NOA and 7-B3 inhibited DR5::GUS expression induced by IAA and 2,4-D, but not that induced by NAA. At high concentrations, 1-NOA exhibited auxin activity, but 7-B3 did not. Furthermore, 7-B3 inhibited apical hook formation in etiolated seedlings more effectively than did 1-NOA. These results indicate that 7-B3 is a potential inhibitor of IAA influx that has almost no effect on IAA efflux or auxin signaling.
    Plant signaling & behavior 05/2014; 9.
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    ABSTRACT: Auxin is a fundamental plant hormone and its localization within organs plays pivotal roles in plant growth and development. Analysis of many Arabidopsis mutants defective in auxin biosynthesis revealed that the indole-3-pyruvic acid (IPA) pathway, catalyzed by the TRYPTOPHAN AMINOTRANSFERASE OF ARABIDOPSIS (TAA) and YUCCA (YUC) families, is the major biosynthetic pathway of indole-3-acetic acid (IAA). In contrast, little is known about the molecular mechanisms of auxin biosynthesis in rice. In this study, we identified a auxin-related rice mutant, fish bone (fib). FIB encodes an ortholog of TAA genes and loss of FIB function resulted in pleiotropic abnormal phenotypes, such as small leaves with large lamina joint angles, abnormal vascular development, small panicles, abnormal organ identity and defects in root development, together with a reduction in internal IAA levels. Moreover, we found that auxin sensitivity and polar transport activity were altered in the fib mutant. From these results, we suggest that FIB plays a pivotal role in IAA biosynthesis in rice and that auxin biosynthesis, transport and sensitivity are closely interrelated.This article is protected by copyright. All rights reserved.
    The Plant Journal 03/2014; · 6.82 Impact Factor
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    ABSTRACT: Increasing crop production is essential for securing the future food supply in developing countries in Asia and Africa as economies and populations grow. However, although the Green Revolution led to increased grain production in the 1960s, no major advances have been made in increasing yield potential in rice since then. In this study, we identified a gene, SPIKELET NUMBER (SPIKE), from a tropical japonica rice landrace that enhances the grain productivity of indica cultivars through pleiotropic effects on plant architecture. Map-based cloning revealed that SPIKE was identical to NARROW LEAF1 (NAL1), which has been reported to control vein pattern in leaf. Phenotypic analyses of a near-isogenic line of a popular indica cultivar, IR64, and overexpressor lines revealed increases in spikelet number, leaf size, root system, and the number of vascular bundles, indicating the enhancement of source size and translocation capacity as well as sink size. The near-isogenic line achieved 13–36% yield increase without any negative effect on grain appearance. Expression analysis revealed that the gene was expressed in all cell types: panicles, leaves, roots, and culms supporting the pleiotropic effects on plant architecture. Furthermore, SPIKE increased grain yield by 18% in the recently released indica cultivar IRRI146, and increased spikelet number in the genetic background of other popular indica cultivars. The use of SPIKE in rice breeding could contribute to food security in indica-growing regions such as South and Southeast Asia.
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    ABSTRACT: Indole-3-acetic acid (IAA), a plant hormone auxin, is biosynthesized from tryptophan. The indole-3-pyruvic acid (IPyA) pathway, involving TAA1 and YUCCA (YUC) enzymes, was recently found to be a major IAA biosynthetic pathway in Arabidopsis. TAA1 catalyzes the conversion of tryptophan to IPyA, and YUC produces IAA from IPyA. Using a chemical biology approach with maize coleoptiles, we identified 5-(4-chlorophenyl)-4H-1,2,4-triazole-3-thiol (yucasin) as a potent inhibitor of IAA biosynthesis in YUC-expressing coleoptile tips. Enzymatic analysis of recombinant AtYUC1-His suggested that yucasin strongly inhibited YUC1-His activity in a competitive manner against the substrate IPyA. Phenotypic analysis of Arabidopsis YUC1 overexpression (35S::YUC1) lines demonstrated that yucasin acts in IAA biosynthesis catalyzed by YUC. Also, 35S::YUC1 seedlings showed resistance to yucasin in root growth. A loss-of-function mutant of TAA1, sav3-2, was hypersensitive to yucasin in root growth and hypocotyl elongation of etiolated seedlings. Yucasin combined with the TAA1 inhibitor L-kynurenine acted additively in Arabidopsis seedlings, producing a phenotype similar to yucasin-treated sav3-2 seedlings, indicating the importance of IAA biosynthesis via the IPyA pathway in root growth and leaf vascular development. The present study showed that yucasin is a potent inhibitor of YUCs that offers an effective tool for analyzing the contribution of IAA biosynthesis via the IPyA pathway to plant development and physiological processes. This article is protected by copyright. All rights reserved.
    The Plant Journal 12/2013; · 6.82 Impact Factor
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    ABSTRACT: Increasing crop production is essential for securing the future food supply in developing countries in Asia and Africa as economies and populations grow. However, although the Green Revolution led to increased grain production in the 1960s, no major advances have been made in increasing yield potential in rice since then. In this study, we identified a gene, SPIKELET NUMBER (SPIKE), from a tropical japonica rice landrace that enhances the grain productivity of indica cultivars through pleiotropic effects on plant architecture. Map-based cloning revealed that SPIKE was identical to NARROW LEAF1 (NAL1), which has been reported to control vein pattern in leaf. Phenotypic analyses of a near-isogenic line of a popular indica cultivar, IR64, and overexpressor lines revealed increases in spikelet number, leaf size, root system, and the number of vascular bundles, indicating the enhancement of source size and translocation capacity as well as sink size. The near-isogenic line achieved 13-36% yield increase without any negative effect on grain appearance. Expression analysis revealed that the gene was expressed in all cell types: panicles, leaves, roots, and culms supporting the pleiotropic effects on plant architecture. Furthermore, SPIKE increased grain yield by 18% in the recently released indica cultivar IRRI146, and increased spikelet number in the genetic background of other popular indica cultivars. The use of SPIKE in rice breeding could contribute to food security in indica-growing regions such as South and Southeast Asia.
    Proceedings of the National Academy of Sciences 12/2013; · 9.81 Impact Factor
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    ABSTRACT: Increasing crop production is essential for securing the future food supply in developing countries in Asia and Africa as economies and populations grow. However, although the Green Revolution led to increased grain production in the 1960s, no major advances have been made in increasing yield potential in rice since then. In this study, we identified a gene, SPIKELET NUMBER (SPIKE), from a tropical japonica rice landrace that enhances the grain productivity of indica cultivars through pleiotropic effects on plant architecture. Map-based cloning revealed that SPIKE was identical to NARROW LEAF1 (NAL1), which has been reported to control vein pattern in leaf. Phenotypic analyses of a near-isogenic line of a popular indica cultivar, IR64, and overexpressor lines revealed increases in spikelet number, leaf size, root system, and the number of vascular bundles, indicating the enhancement of source size and translocation capacity as well as sink size. The near-isogenic line achieved 13-36% yield increase without any negative effect on grain appearance. Expression analysis revealed that the gene was expressed in all cell types: panicles, leaves, roots, and culms supporting the pleiotropic effects on plant architecture. Furthermore, SPIKE increased grain yield by 18% in the recently released indica cultivar IRRI146, and increased spikelet number in the genetic background of other popular indica cultivars. The use of SPIKE in rice breeding could contribute to food security in indica-growing regions such as South and Southeast Asia.
    Proceedings of the National Academy of Sciences 12/2013; · 9.81 Impact Factor
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    ABSTRACT: Plant aldehyde oxidases (AOs) have gained great attention during the last years as they catalyze the last step in the biosynthesis of the phytohormone abscisic acid by oxidation of abscisic aldehyde. Furthermore, oxidation of indole-3-acetaldehyde by AOs is likely to represent one route to produce another phytohormone, indole-3-acetic acid, and thus, AOs play important roles in many aspects of plant growth and development. In the present work we demonstrate that heterologously expressed AAO1 and AAO3, two prominent members of the AO family from Arabidopsis thaliana, do not only generate hydrogen peroxide but also superoxide anions by transferring aldehyde-derived electrons to molecular oxygen. In support of this, superoxide production has also been found for native AO proteins in Arabidopsis leaf extracts. In addition to their aldehyde oxidation activity, AAO1 and AAO3 were found to exhibit NADH oxidase activity, which likewise is associated with the production of superoxide anions. According to these results and due to the fact that molecular oxygen is the only known physiological electron acceptor of AOs, the production of hydrogen peroxide and/or superoxide has to be considered in any physiological condition in which aldehydes or NADH serve as substrate for AOs. In this respect, conditions such as natural senescence and stress-induced stomatal movement, which both require simultaneously elevated levels of abscisic acid and hydrogen peroxide/superoxide, are likely to benefit from AOs in two ways, namely by formation of abscisic acid and by concomitant formation of reactive oxygen species.
    Plant Molecular Biology 10/2012; · 4.07 Impact Factor
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    ABSTRACT: The monocot coleoptile tip region has been generally supposed to be the source of IAA to supply IAA to basal parts by the polar IAA transport system, which results in gravi- and phototropic curvature of coleoptiles. Based on this IAA transport system and gravitropism of maize coleoptiles, we have developed two screening methods to identify small molecules from a large chemical library that inhibit IAA transport. The methods detect molecules that affect (i) gravitropic curvature of coleoptiles; and (ii) the amount of IAA transported from the tip. From 10,000 chemicals, eight compounds were identified and categorized into two groups. Four chemicals in group A decreased IAA transport from the tip, and increased endogenous IAA levels in the tip. The structures of two compounds resembled that of 1-N-naphthylphthalamic acid (NPA), but those of the other two differed from structures of known IAA transport inhibitors. Four chemicals in group B strongly inhibited IAA transport from the tip, but IAA levels at the tip were only slightly affected. At higher concentrations, group B compounds inhibited germination of Arabidopsis, similarly to brefeldin A (BFA). Analysis of the cellular distribution of PIN2-green fluorescent protein (GFP) and PIN1-GFP in Arabidopsis revealed that one of the four chemicals in group B induced internalization of PIN1 and PIN2 proteins into vesicles smaller than BFA bodies, suggesting that this compound affects cellular vesicle trafficking systems related to PIN trafficking. The eight chemicals identified here will be a useful tool for understanding the mechanisms of IAA transport in plants.
    Plant and Cell Physiology 08/2012; 53(10):1671-82. · 4.98 Impact Factor
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    ABSTRACT: Movement of the plant hormone abscisic acid (ABA) within plants has been documented; however, the molecular mechanisms that regulate ABA transport are not fully understood. By using a modified yeast two-hybrid system, we screened Arabidopsis cDNAs capable of inducing interactions between the ABA receptor PYR/PYL/RCAR and PP2C protein phosphatase under low ABA concentrations. By using this approach, we identified four members of the NRT1/PTR family as candidates for ABA importers. Transport assays in yeast and insect cells demonstrated that at least one of the candidates ABA-IMPORTING TRANSPORTER (AIT) 1, which had been characterized as the low-affinity nitrate transporter NRT1.2, mediates cellular ABA uptake. Compared with WT, the ait1/nrt1.2 mutants were less sensitive to exogenously applied ABA during seed germination and/or postgermination growth, whereas overexpression of AIT1/NRT1.2 resulted in ABA hypersensitivity in the same conditions. Interestingly, the inflorescence stems of ait1/nrt1.2 had a lower surface temperature than those of the WT because of excess water loss from open stomata. We detected promoter activities of AIT1/NRT1.2 around vascular tissues in inflorescence stems, leaves, and roots. These data suggest that the function of AIT1/NRT1.2 as an ABA importer at the site of ABA biosynthesis is important for the regulation of stomatal aperture in inflorescence stems.
    Proceedings of the National Academy of Sciences 05/2012; 109(24):9653-8. · 9.81 Impact Factor
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    ABSTRACT: To investigate the distribution of IAA (indole-3-acetic acid) and the IAA synthetic cells in maize coleoptiles, we established immunohistochemistry of IAA using an anti-IAA-C-monoclonal antibody. We first confirmed the specificity of the antibody by comparing the amounts of endogenous free and conjugated IAA to the IAA signal obtained from the IAA antibody. Depletion of endogenous IAA showed a corresponding decrease in immuno-signal intensity and negligible cross-reactivity against IAA-related compounds, including tryptophan, indole-3-acetamide, and conjugated-IAA was observed. Immunolocalization showed that the IAA signal was intense in the approximately 1 mm region and the outer epidermis at the approximately 0.5 mm region from the top of coleoptiles treated with 1-N-naphthylphthalamic acid. By contrast, the IAA immuno-signal in the outer epidermis almost disappeared after 5-methyl-tryptophan treatment. Immunogold labeling of IAA with an anti-IAA-N-polyclonal antibody in the outer-epidermal cells showed cytoplasmic localization of free-IAA, but none in cell walls or vacuoles. These findings indicated that IAA is synthesized in the 0–2.0 mm region of maize coleoptile tips from Trp, in which the outer-epidermal cells of the 0.5 mm tip are the most active IAA synthetic cells.
    Plant signaling & behavior 12/2011; 6(12):2013-22.
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    ABSTRACT: Cucumber (Cucumis sativus) seedlings grown in a horizontal position develop a specialized protuberance (or peg) on the lower side of the transition zone between the hypocotyl and the root. This occurs by suppressing peg formation on the upper side via a decrease in auxin resulting from a gravitational response. However, the gravity-stimulated mechanism of inducing asymmetric auxin distribution in the transition zone is poorly understood. The gravity-sensing tissue responsible for regulating auxin distribution in the transition zone is thought to be the endodermal cell. To characterize the gravity-stimulated mechanism, the auxin efflux facilitator PIN-FORMED1 (CsPIN1) in the endodermis was identified and the localization of CsPIN1 proteins during the gravimorphogenesis of cucumber seedlings was examined. Immunohistochemical analysis revealed that the accumulation pattern of CsPIN1 protein in the endodermal cells of the transition zone of cucumber seedlings grown horizontally differed from that of plants grown vertically. Gravistimulation for 30 min prompted changes in the accumulation pattern of CsPIN1 protein in the endodermis as well as the asymmetric distribution of auxin in the transition zone. Furthermore, 2,3,5-triiodobenzoic acid inhibited the differential distribution of auxin as well as changes in the accumulation pattern of CsPIN1 in the endodermis of the transition zone during gravistimulation. These results suggest that the altered pattern of CsPIN1 accumulation in the endodermis in response to gravistimulation influences lateral auxin transport through the endodermis, resulting in asymmetric auxin distribution in the transition zone.
    Plant physiology 11/2011; 158(1):239-51. · 7.39 Impact Factor
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    ABSTRACT: When grafting or wounding disconnects stem tissues, new tissues are generated to restore the lost connection. In this study, the molecular mechanism of such healing was elucidated in injured stems of Arabidopsis. Soon after the inflorescence stems were incised, the pith cells started to divide. This process was strongly inhibited by the elimination of cauline leaves, shoot apices, or lateral buds that reduced the indole-3-acetic acid supply. Microarray and quantitative RT-PCR analyses revealed that genes related to cell division, phytohormones, and transcription factors were expressed because of incision. Among them, two plant-specific transcription factor genes, ANAC071 and RAP2.6L, were abundantly expressed. ANAC071 was expressed at 1-3 d after cutting exclusively in the upper region of the cut gap, with concomitant accumulation of indole-3-acetic acid. In contrast, RAP2.6L was expressed at 1 d after cutting exclusively in the lower region, with concomitant deprivation of indole-3-acetic acid. The expression of ANAC071 and RAP2.6L were also promoted by ethylene and jasmonic acid, respectively. In transformants suppressing the function of RAP2.6L or ANAC071, the division of pith cells was inhibited. Furthermore, the ethylene signaling-defective ein2 mutant showed incomplete healing. Hence, plant-specific transcription factors differentially expressed around the cut position were essential for tissue reunion of Arabidopsis wounded flowering stems and were under opposite control by polar-transported auxin, with modification by the ethylene and jasmonic acid wound-inducible hormones.
    Proceedings of the National Academy of Sciences 09/2011; 108(38):16128-32. · 9.81 Impact Factor
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    ABSTRACT: Superoxide dismutase (SOD) and ascorbate peroxidase (APX) play central roles in the pathway for scavenging reactive oxygen species in plants, thereby contributing to the tolerance against abiotic stress. Here we report the responses of cytosolic SOD (cSOD; sodCc1 and sodCc2) and cytosolic APX (cAPX; OsAPX1 and OsAPX2) genes to oxidative and abiotic stress in rice. RNA blot analyses revealed that methyl viologen treatment caused a more prominent induction of cAPXs compared with cSODs, and hydrogen peroxide treatment induced the expression of cAPXs whereas cSODs were not affected. These results suggest that cAPXs play more important roles in defense against oxidative stress compared with cSODs. It is noted that cSODs and cAPXs showed coordinate response to abscisic acid treatment which induced both sodCc1 and OsAPX2. However, cSODs and cAPXs responded differentially to drought, salt and chilling stress, which indicates that cSOD and cAPX genes are expressed differentially in response to oxidative and abiotic stress in rice.
    Rice Science 09/2011; 18(3):157–166.
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    ABSTRACT: Plant roots play important roles not only in the absorption of water and nutrients, but also in stress tolerance. Previously, we identified RSOsPR10 as a root-specific pathogenesis-related (PR) protein induced by drought and salt treatments in rice. Transcripts and proteins of RSOsPR10 were strongly induced by jasmonate (JA) and the ethylene (ET) precursor 1-aminocyclopropane-1-carboxylic acid (ACC), while salicylic acid (SA) almost completely suppressed these inductions. Immunohistochemical analyses showed that RSOsPR10 strongly accumulated in cortex cells surrounding the vascular system of roots, and this accumulation was also suppressed when SA was applied simultaneously with stress or hormone treatments. In the JA-deficient mutant hebiba, RSOsPR10 expression was up-regulated by NaCl, wounding, drought and exogenous application of JA. This suggested the involvement of a signal transduction pathway that integrates JA and ET signals in plant defense responses. Expression of OsERF1, a transcription factor in the JA/ET pathway, was induced earlier than that of RSOsPR10 after salt, JA and ACC treatments. Simultaneous SA treatment strongly inhibited the induction of RSOsPR10 expression and, to a lesser extent, induction of OsERF1 expression. These results suggest that JA/ET and SA pathways function in the stress-responsive induction of RSOsPR10, and that OsERF1 may be one of the transcriptional factors in the JA/ET pathway.
    Plant and Cell Physiology 08/2011; 52(9):1686-96. · 4.98 Impact Factor
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    ABSTRACT: Phototropic curvature results from differential growth on two sides of the elongating shoot, which is explained by asymmetrical indole-3-acetic acid (IAA) distribution. Using 2 cm maize coleoptile segments, 1st positive phototropic curvature was confirmed here after 8 s irradiation with unilateral blue light (0.33 μmol m(-2) s(-1)). IAA was redistributed asymmetrically by approximately 20 min after photo-stimulation. This asymmetric distribution was initiated in the top 0-3 mm region and was then transmitted to lower regions. Application of the IAA transport inhibitor, 1-N-naphthylphthalamic acid (NPA), to the top 2 mm region completely inhibited phototropic curvature, even when auxin was simultaneously applied below the NPA-treated zone. Thus, lateral IAA movement occurred only within the top 0-3 mm region after photo-stimulation. Localized irradiation experiments indicated that the photo-stimulus was perceived in the apical 2 mm region. The results suggest that this region harbours key components responsible for photo-sensing and lateral IAA transport. In the present study, it was found that the NPH3- and PGP-like genes were exclusively expressed in the 0-2 mm region of the tip, whereas PHOT1 and ZmPIN1a, b, and c were expressed relatively evenly along the coleoptile, and ZmAUX1, ZMK1, and ZmSAURE2 were strongly expressed in the elongation zone. These results suggest that the NPH3-like and PGP-like gene products have a key role in photo-signal transduction and regulation of the direction of auxin transport after blue light perception by phot1 at the very tip region of maize coleoptiles.
    Journal of Experimental Botany 03/2011; 62(10):3459-66. · 5.79 Impact Factor
  • Mitsunori Seo, Tomokazu Koshiba
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    ABSTRACT: There is substantial evidence that abscisic acid (ABA) moves within plants. ABA has been considered as a root-derived signaling molecule that induces stomatal closure in response to dry soil conditions. It has been also reported that ABA synthesized in vegetative tissues is translocated to the seeds. The transport of ABA is an important factor in determining the endogenous concentrations of the hormone at the site of action, and hence, it is an important process in physiological responses. However, the molecular mechanisms that regulate ABA transport are not fully understood. Recent studies using Arabidopsis indicate that ABA is actively synthesized in leaf vascular tissues in response to drought, and that ABA is subsequently transported to the guard cells to close stomata. Identification of the transporters that mediate ABA export from the inside to the outside of the cells at the site of ABA biosynthesis (vascular tissues) and ABA uptake into the cells at the site of action (guard cells), respectively, in this species indicates an active mechanism to regulate ABA transport. Although Arabidopsis represents only one model plant, these findings are useful to discuss common or different regulatory mechanisms among different species and to improve our total understanding of the regulation of ABA transport.
    Journal of Plant Research 03/2011; 124(4):501-7. · 2.51 Impact Factor

Publication Stats

4k Citations
421.67 Total Impact Points

Institutions

  • 1993–2015
    • Tokyo Metropolitan University
      • • Department of Biological Sciences
      • • Department of Chemistry
      Edo, Tōkyō, Japan
  • 2009
    • University of Toronto
      • Department of Cell and Systems Biology
      Toronto, Ontario, Canada
  • 2004–2005
    • RIKEN
      Вако, Saitama, Japan
  • 2003
    • The University of Tokyo
      • Department of Biological Sciences
      Tōkyō, Japan
  • 1998–2002
    • Hokkaido University
      • • Division of Biological Sciences
      • • Division of Biological Sciences (Biology)
      Sapporo-shi, Hokkaido, Japan
  • 1999
    • Saitama University
      • Graduate School of Science and Engineering
      Saitama, Saitama, Japan