Hirokazu Tsukaya

The University of Tokyo, Tōkyō, Japan

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Publications (163)638.32 Total impact

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    ABSTRACT: Plant peptides play important roles in various aspects of plant growth and development. The RTFL/DVL family includes small peptides that are widely conserved among land plants. Overexpression of six RTFL genes in Arabidopsis was suggestive of their functions as negative regulators of cell proliferation and as positional cues along the longitudinal axis of the plant body . At this time, few reports are available on RTFL paralogs in other species and the evolutionary relationship of RTFL members among land plants remains unclear. In this study, we compared and analyzed whole amino acid sequences of 188 RTFL members from 22 species among land plants and identified 73 motifs. All RTFL members could be grouped into four clades, and each clade exhibited specific motif patterns, indicative of unique evolutionary traits in the RTFL family. In agreement with this hypothesis, we analyzed two RTFL members from Oryza sativa and Arabidopsis by overexpressing them in Arabidopsis, revealing similar phenotypes suggestive of a conserved function of the RTFL family between eudicots and monocots, as well as different phenotypes and unique functions.
    Journal of plant research. 02/2015;
  • Tetsuya Hisanaga, Kensuke Kawade, Hirokazu Tsukaya
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    ABSTRACT: Leaves are ideal model systems to study the organ size regulation of multi-cellular plants. Leaf cell number and cell size are determinant factors of leaf size which is controlled through cell proliferation and post-mitotic cell expansion, respectively. To achieve a proper leaf size, cell proliferation and post-mitotic cell expansion should be co-ordinated during leaf morphogenesis. Compensation, which is enhanced post-mitotic cell expansion associated with a decrease in cell number during lateral organ development, is suggestive of such co-ordination. Genetic and kinematic studies revealed at least three classes of modes of compensation, indicating that compensation is a heterogeneous phenomenon. Recent studies have increased our understanding about the molecular basis of compensation by identifying the causal genes of each compensation-exhibiting mutant. Furthermore, analyses using chimeric leaves revealed that a type of compensated cell expansion requires cell-to-cell communication. Information from recent advances in molecular and genetic studies on compensation has been integrated here and its role in organ size regulation is discussed. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.
    Journal of Experimental Botany 01/2015; · 5.79 Impact Factor
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    ABSTRACT: Morphological and molecular variation between Arundina graminifolia var. graminifolia and the dwarf variety, A. graminifolia var. revoluta, was examined to assess the validity of their taxonomic characteristics and genetic background for identification. Morphological analysis in combination with field observations indicated that A. graminifolia var. revoluta is a rheophyte form of A. graminifolia characterized by narrow leaves, whereas the other morphological characteristics described for A. graminifolia var. revoluta, such as smaller flowers and short stems, were not always accompanied by the narrower leaf phenotype. Molecular analysis based on matK sequences indicated that only partial differentiation has occurred between A. graminifolia var. graminifolia and A. graminifolia var. revoluta. Therefore, we should consider the rheophyte form an ecotype rather than a variety. Anatomical observations of the leaves revealed that the rheophyte form of A. graminifolia possessed characteristics of the rheophytes of both ferns and angiosperms, such as narrower palisade tissue cells and thinner spongy tissue cells, as well as fewer cells in the leaf-width direction and fewer mesophyll cell layers.
    Journal of Plant Research 12/2014; · 2.51 Impact Factor
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    ABSTRACT: The postembryonic development of aboveground plant organs relies on a continuous supply of cells from the shoot apical meristem. Previous studies of developmental regulation in leaves and flowers have revealed the crucial role of coordinated cell proliferation and differentiation during organogenesis. However, the importance of this coordination has not been examined in flowering stems. Very recently, we attempted to identify regulatory factors that maintain flowering stem integrity. We found that the increased cell number in clavata (clv) mutants and the decreased cell size in de-etiolated (det)3-1 resulted in flowering stems that were thicker and thinner, respectively, than in wild-type (WT) plants. Interestingly, in the cell proliferation- and cell expansion-defective double mutant clv det3-1, the flowering stems often exhibited severe cracking, resulting in exposure of their inner tissues. In this study, further quantification of the cellular phenotypes in the cotyledons and leaves revealed no differences between det3-1 and clv3 det3-1. Together, the above findings suggest that the clv3 mutation in a det3-1 background primarily affects flowering stems, while its effect on other organs is likely negligible. We propose that the coordination between cell proliferation and differentiation is not only important during leaf development, but also plays a role in the growth control of Arabidopsis flowering stems.
    Plant signaling & behavior 11/2014; In press.
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    ABSTRACT: Plant shoot organs such as stems, leaves, and flowers are derived from specialized groups of stem cells organized at the shoot apical meristem (SAM). Organogenesis involves two major processes, namely, cell proliferation and differentiation, whereby the former contributes to increasing the cell number and the latter involves substantial increases in cell volume through cell expansion. Coordination between the above processes in time and space is essential for proper organogenesis. To identify regulatory factors involved in proper organogenesis, heavy-ion beam-irradiated de-etiolated (det) 3-1 seeds have been used to identify striking phenotypes in the A#26-2; det3-1 mutant. In addition to the stunted plant stature mimicking det3-1, the A#26-2; det3-1 mutant exhibited stem thickening, increased floral organ number, and a fruit shape reminiscent of clavata (clv) mutants. DNA sequencing analysis demonstrated that A#26-2; det3-1 harbors a mutation in the CLV3 gene. Importantly, A#26-2; det3-1 displayed cracks that randomly occurred on the main stem with a frequency of ~50%. Furthermore, the double mutants clv3-8 det3-1, clv1-4 det3-1, and clv2-1 det3-1 consistently showed stem cracks with frequencies of ~97%, 38%, and 35%, respectively. Cross sections of stems further revealed an increase in vascular bundle number, cell number, and size in the pith of clv3-8 det3-1 compared to det3-1. These findings suggest that the stem inner volume increase due to clv mutations exerts an outward mechanical stress; that in a det3-1 background (defective in cell expansion) resulted in cracking of the outermost layer of epidermal cells.
    Plant and Cell Physiology 09/2014; In press. · 4.98 Impact Factor
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    ABSTRACT: The Cayratia japonica-Cayratia tenuifolia species complex (Vitaceae) is distributed from temperate to tropical East Asia, Southeast Asia, India, and Australia. The spatiotemporal diversification history of this complex was assessed through phylogenetic and biogeographic analyses. Maximum parsimony, neighbor-joining, and maximum likelihood methods were used to analyze sequences of one nuclear (AS1) and two plastid regions (trnL-F and trnC-petN). Bayesian dating analysis was conducted to estimate the divergence times of clades. The likelihood method LAGRANGE was used to infer ancestral areas. The Asian C. japonica and C. tenuifolia should be treated as an unresolved complex, and Australian C. japonica is distinct from the Asian C. japonica-C. tenuifolia species complex and should be treated as separate taxa. The Asian C. japonica-C. tenuifolia species complex was estimated to have diverged from its closest relatives during the Late Eocene (35.1 million years ago [Ma], 95% highest posterior densities [HPD] = 23.3-47.3 Ma) and most likely first diverged in mid-continental Asia. This complex was first divided into a northern clade and a southern clade during the middle Oligocene (27.3 Ma; 95% HPD = 17.4-38.1 Ma), which is consistent with a large southeastward extrusion of the Indochina region relative to South China along the Red River. Each of the northern and southern clades then further diverged into multiple subclades through a series of dispersal and divergence events following significant geological and climatic changes in East and Southeast Asia during the Miocene. Multiple inter-lineage hybridizations among four lineages were inferred to have occurred following this diversification process, which caused some Asian lineages to be morphologically cryptic.
    Molecular Phylogenetics and Evolution 06/2014; · 4.02 Impact Factor
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    ABSTRACT: In compound leaves, leaflet primordia are initiated directionally along the lateral sides. Our understanding of the molecular basis of leaflet initiation has improved, but the regulatory mechanisms underlying spatio-temporal patterns remain unclear. In this study, we investigated the mechanisms of acropetal (from the base to the tip) progression of leaflet initiation in Eschscholzia californica. We established an ultraviolet-laser ablation system to manipulate compound-leaf development. Local ablation at the leaflet incipient site generated leaves with asymmetric morphology. In the majority of cases, leaflets that were initiated on the ablated sides shifted apically. Finite time-course observation revealed that the timing of leaflet initiation was delayed, but the distance from the leaf tip did not decrease. These results were suggestive of the local spacing mechanism in leaflet initiation, whereby the distance from the leaf tip and adjacent pre-existing leaflet determines the position of leaflet initiation. To understand how such a local patterning mechanism generates a global pattern of successive leaflet initiation, we assessed the growth rate gradient along the apical-basal axis. Our time-course analysis revealed differential growth rates along the apical-basal axis of the leaf, which can explain the acropetal progression of leaflet initiation. We propose that a leaflet is initiated at a site where the distances from pre-existing leaflets and the leaf tip are sufficient. Furthermore, the differential growth rate may be a developmental factor underlying the directionality of leaflet initiation.
    Planta 04/2014; · 3.38 Impact Factor
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    Hirokazu Tsukaya, Monica Suleiman, Hiroshi Okada
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    ABSTRACT: The genus Thismia Griff. (Thismiaceae) comprises more than 45 mycoheterotrophic species (Jonker 1948; Merckx 2008; Merckx et al. 2013), including several species described within the past decade, such as T. mullarensis from Central Kalimantan (Tsukaya & Okada 2005), T. betung-kerihunensis from West Kalimantan (Tsukaya & Okada 2012a), and T. hexagona from Brunei (Dančák et al. 2013). The majority of these species appear to have been collected only once or a few times. Since mycoheterotrophs are highly dependent on the activities of both the fungi and the trees that sustain them, the richness of the myco-heterotroph flora is a good indicator of the floris-tic richness of the forests in which they occur (Merckx et al. 2013). In other words, mycohetero-trophs are easily affected by ecosystem destruction. To conserve the biodiversity of tropical forests , we need additional information on the distribution of such vulnerable mycoheterotrophs. In our floristic studies in the Kalimantan area of Borneo we found one new genus, several new species, and a new variety of mycoheterotrophs (Tsukaya & Okada 2005, 2012a, 2012b, 2013a, 2013b, Tsukaya et al. 2011). Because Kalimantan has a rich diversity of mycoheterotrophs, we compared the mycoheterotroph floras of Kali-mantan and Sabah, Borneo, starting with a botanical expedition in Maliau Basin Conservation Area, Sabah, with permission from the Maliau Basin Management Committee (YS/MBMC/ 2013/50) and Sabah Biodiversity Council [access license JKM/MBS.1000-2/2(152)]. We chose this area because Dr. Tim Utteridge, of the Royal Bo-tanic Gardens, Kew, kindly showed one of us (HT) photographs of Thismia that he took in the conservation area. We suspected the photos to represent a new species of Thismia, based on oth-A New Variety of Thismia hexagona Dančák, Hroneš, Koblová et
    Acta Phytotaxonomica et Geobotanica. 03/2014; 65(3):141-145..
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    Hirokazu Tsukaya, Monica Suleiman, Hiroshi Okada
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    ABSTRACT: Mycohetetrotrophic plants lack chlorophyll and depend on mycorrhizal fungi for nutrients (Hynson et al. 2013) and are most abundant in tropical forests. Didymoplexiella Garay (Orchi-daceae, subfamily Epidendroideae, tribe Gastro-dieae, subtribe Gastrodiinae) and Didymoplexis Griff. (subtribe Gastrodiinae) are mycoheterotro-phic and closely related, differing only in the presence (Didymoplexiella) or absence (Didymo-plexis) of stelidia (Garay 1954). Didymoplexiella Garay is composed of nine species, five of which occur in Borneo (Wood & Cribb, 1994). The other species include D. denticulata Aver., described from Vietnam (Averyanov 2010), D. hainanensis X.H. Jin & S.C. Chen, described from Hainan, China (Jin et al. 2004), and D. siamensis (Rolfe ex Downie) Seidenf., which is known from Thai-land, Hainan and Taiwan, China, and Yakushi-ma, Japan (Chen et al. 2009). Didymoplexiella trichechus (J.J. Sm.) Garay was reported from Banca (Bangka) Island, Sumatra (Smith 1920) and on Mt. Talamau, Sumatra (Comber 2001), but not from outside Sumatra. Didymoplexis Griff. (subtribe Gastrodiinae) contains approximately 20 species, 3 of which: D. latilabris Schltr., D. pallens Griff, and D. striata J.J. Sm., occur on Borneo (Wood & Cribb, 1994). Recently, we (H.T. and H.O.) reported the occurrence of D. cornuta var. betung-kerihunensis Tsukaya & H.Okada in West Kalimantan, Bor-neo. Didymoplexis cornuta var. cornuta was known only from near Bogor, West Java (Smith 1925). The disjunct distribution in Java and West Kalimantan suggests that D. cornuta may also be found in other areas. During floristic studies in Central and West Kalimantan we named a new genus, several new species, and a new mycoheterotroph (Tsukaya & Short CommuniCation
    03/2014; 65(2):105-110.
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    Hirokazu Tsukaya
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    ABSTRACT: Recent accumulation of our knowledge on basic leaf development mechanisms in model angiosperm species has allowed us to pursue evolutionary development (evo/devo) studies of various kinds of leaf development. As a result, unexpected findings and clues have been unearthed aiding our understanding of the mechanisms involved in the diversity of leaf morphology, although the covered remain limited. In this review, we highlight recent findings of diversified leaf development in angiosperms.
    Current opinion in plant biology 02/2014; 17C:103-109. · 10.33 Impact Factor
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    ABSTRACT: Plant development has been evaluated at various developmental stages, from the early steps of embryogenesis to flowering. In most reports, transcription factors have been thought to play a master regulatory role in the complex networks orchestrating organogenesis. Although these efforts have increased our understanding of several major developmental pathways, our understanding of the relationships between metabolism and development remains limited. Recently, we identified a straightforward relationship linking carbohydrate metabolism and organogenesis. We found that plant development, particularly the reactivation of cell cycling after germination and the transition from heterotrophic to autotrophic growth, are highly dependent on sucrose availability. In the case of Arabidopsis thaliana, an oilseed species, we characterized the importance of cytosolic inorganic pyrophosphate hydrolysis for the success of the above transition and appropriate execution of postembryonic developmental programs. While this unprecedented and unique discovery has addressed fundamental issues concerning the biological role of the proton-pyrophosphatase (H+-PPase), it has also raised questions regarding the link between metabolism and development. Here, we summarize our present knowledge of key steps in the mobilization of storage lipids and their impact together with H+-PPase during the heterotrophic-autotrophic growth transition.
    Plant Morphology. 01/2014; 26:45-51.
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    ABSTRACT: To gain more insight into the physiological function of nitrogen dioxide (NO2 ), we investigated the effects of exogenous NO2 on growth in Arabidopsis thaliana. Plants were grown in air without NO2 for 1 wk after sowing and then grown for 1-4 wk in air with (designated treated plants) or without (control plants) NO2 . Plants were irrigated semiweekly with a nutrient solution containing 19.7 mM nitrate and 10.3 mM ammonium. Five-week-old plants treated with 50 ppb NO2 showed a ≤ 2.8-fold increase in biomass relative to controls. Treated plants also showed early flowering. The magnitude of the effects of NO2 on leaf expansion, cell proliferation and enlargement was greater in developing than in maturing leaves. Leaf areas were 1.3-8.4 times larger on treated plants than corresponding leaves on control plants. The NO2 -induced increase in leaf size was largely attributable to cell proliferation in developing leaves, but was attributable to both cell proliferation and enlargement in maturing leaves. The expression of different sets of genes for cell proliferation and/or enlargement was induced by NO2 , but depended on the leaf developmental stage. Collectively, these results indicated that NO2 regulates organ growth by controlling cell proliferation and enlargement.
    New Phytologist 12/2013; · 6.55 Impact Factor
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    Hirokazu Tsukaya
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    ABSTRACT: Ploidy level affects cell size in many organisms, and ploidy-dependent cell enlargement has been used to breed many useful organisms. However, how polyploidy affects cell size remains unknown. Previous studies have explored changes in transcriptome data caused by polyploidy, but have not been successful. The most naïve theory explaining ploidy-dependent cell enlargement is that increases in gene copy number increase the amount of protein, which in turn increases the cell volume. This hypothesis can be evaluated by examining whether any strains, mutants, or transgenics show the same cell size before and after a tetraploidization event. I performed this experiment by tetraploidizing various mutants and transgenics of Arabidopsis thaliana, which show a wide range in cell size, and found that the ploidy-dependent increase in cell volume is genetically regulated. This result is not in agreement with the theory described above.
    PLoS ONE 12/2013; 8(12):e83729. · 3.53 Impact Factor
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    ABSTRACT: Compensation refers to an increase in cell size when the cell number is significantly decreased due to the mutation or gain of function of a gene that negatively affects the cell cycle. Given the importance of coordinated growth during organogenesis in both animal and plant systems, compensation is important to understand the mechanism of size regulation. In leaves, cell division precedes cell differentiation (which involves cell expansion); therefore, a decrease in cell number triggers enhanced cell expansion (compensated cell enlargement; hereafter, CCE). Functional analyses of genes for which a loss or gain of function triggers compensation have increased our understanding of the molecular mechanisms underlying the decrease in cell number. Nevertheless, the mechanisms that induce enhanced cell expansion (the link between cell cycling and expansion), as well as the cellular machinery mediating CCE, have not been characterized. We recently characterized an important pathway involved in cell enlargement in KRP2-overexpressing plants. Here, we discuss the potential axial role of plant KRPs in triggering enlargement in cells with meristematic features.
    Plant signaling & behavior 12/2013; 8(11).
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    ABSTRACT: Compensation refers to an increase in cell size when the cell number is significantly decreased due to the mutation or gain of function of a gene that negatively affects the cell cycle. Given the importance of coordinated growth during organogenesis in both animal and plant systems, compensation is important to understand the mechanism of size regulation. In leaves, cell division precedes cell differentiation (which involves cell expansion); therefore, a decrease in cell number triggers enhanced cell expansion (compensated cell enlargement; hereafter, CCE). Functional analyses of genes for which a loss or gain of function triggers compensation have increased our understanding of the molecular mechanisms underlying the decrease in cell number. Nevertheless, the mechanisms that induce enhanced cell expansion (the link between cell cycling and expansion), as well as the cellular machinery mediating CCE, have not been characterized. We recently characterized an important pathway involved in cell enlargement in KRP2-overexpressing plants. Here, we discuss the potential axial role of plant KRPs in triggering enlargement in cells with meristematic features.
    Plant signaling & behavior 11/2013; In press.
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    ABSTRACT: Leaves are determinate organs; hence, precise control of cell proliferation and post-mitotic cell expansion is essential for their growth. A defect in cell proliferation often triggers enhanced post-mitotic cell expansion in leaves. This phenomenon is referred to as 'compensation'. Several lines of evidence from studies on compensation have shown that cell proliferation and post-mitotic cell expansion are coordinately regulated during leaf development. Therefore, compensation has attracted much attention to the mechanisms for leaf growth. However, our understanding of compensation at the subcellular level remains limited because studies of compensation have focused mainly on cellular-level phenotypes. Proper leaf growth requires quantitative control of subcellular components in association with cellular-level changes. To gain insight into the subcellular aspect of compensation, we investigated the well-known relationship between cell area and chloroplast number per cell in compensation-exhibiting lines, and asked whether chloroplast proliferation is modulated in response to the induction of compensation. We first established a convenient and reliable method for observation of chloroplasts in situ. Using this method, we analyzed Arabidopsis thaliana mutants fugu5 and angustifolia3 (an3), and a transgenic line KIP-RELATED PROTEIN2 overexpressor (KRP2 OE), which are known to exhibit typical features of compensation. We here showed that chloroplast number per cell increased in the subepidermal palisade tissue of these lines. We analyzed tetraploidized wild type, fugu5, an3 and KRP2 OE, and found that cell area itself, but not nuclear ploidy, is a key parameter that determines the activity of chloroplast proliferation. In particular, in the case of an3, we uncovered that promotion of chloroplast proliferation depends on the enhanced post-mitotic cell expansion. The expression levels of chloroplast proliferation-related genes are similar to or lower than that in the wild type during this process. This study demonstrates that chloroplast proliferation is promoted in compensation-exhibiting lines. This promotion of chloroplast proliferation takes place in response to cell-area increase in post-mitotic phase in an3. The expression of chloroplast proliferation-related genes were not promoted in compensation-exhibiting lines including an3, arguing that an as-yet-unknown mechanism is responsible for modulation of chloroplast proliferation in these lines.
    BMC Plant Biology 09/2013; 13(1):143. · 3.94 Impact Factor
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    ABSTRACT: Decreased cell numbers during leaf development often triggers increased cell size, a phenomenon called compensation. In compensation-exhibiting mutants, the unusually high cell expansion activity occurs through two different mechanisms during the post-mitotic stage of leaf development, except in the KIP-RELATED PROTEIN 2 over-expressing line (KRP2 o/e), whose cell sizes are twofold greater during proliferative growth. However, the molecular basis of compensated cell expansion (CCE) has not been characterized. The det3-1 mutant has a mutation in the C-subunit of the V-ATPase complex that causes a 50% decrease in its activity and cell size. To determine the contribution of V-ATPase activity to CCE, the cellular phenotypes of double mutants between det3-1 and compensation-exhibiting fugu5-1, an3-4, fas1-5 and KRP2 o/e were analyzed in detail. Interestingly, while decreased V-ATPase activity caused by det3-1 did not suppress CCE in fugu5-1, fas1-5 and an3-4, CCE in KRP2 o/e was suppressed totally. Furthermore, measurements revealed that the activity and quantity of the A subunit of the V-ATPase complex were significantly increased in the shoots of KRP2 o/e plants. Importantly, the unusually increased size of actively dividing KRP2 o/e cells was restored to normal in the det3-1 background. Taken together, our data strongly suggest that CCE in KRP2 o/e, but not in other compensation-exhibiting mutants, occurs exclusively through the increase of V-ATPase activity.
    Plant and Cell Physiology 09/2013; · 4.98 Impact Factor
  • Hirokazu Tsukaya, Hiroshi Okada
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    ABSTRACT: Abstract— Borneo is one of the richest areas for mycoheterotrophic plants, and six species including one endemic have been recorded for the genus Sciaphila Blume, Triuridaceae. Here, we recognize two previously undescribed species of Sciaphila from botanical surveys in Betung Kerihun National Park, West Kalimantan, Borneo, and provide detailed morphological accounts of both new species, S. betung-kerihunensis and S. brevistyla . We also provide a key to the species of Sciaphila in Borneo.
    Systematic Botany 09/2013; 38(3):600-605. · 1.11 Impact Factor
  • Hokuto Nakayama, Takahiro Yamaguchi, Hirokazu Tsukaya
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    ABSTRACT: It has been suggested that modification and co-option of existing gene regulatory networks (GRNs) play an important role in the morphological diversity. In plants, leaf development is one of active research areas, and the basic GRN for leaf development is beginning to be understood. Moreover, leaves show wide variation in their form, and some of this variation is thought to be the result of adaptation. Thus, leaves and leaf-like organs are an emerging and interesting model to reveal how existing GRNs give rise to novel forms and architectures during evolution. In this review, we highlight recent findings in evo-devo studies, especially on Juncus unifacial leaves, which are composed of lamina with abaxialized identities, and Asparagus cladodes, which are leaf-like organs at the axils of scale leaves. Based on these studies, we discuss how flat structures have evolved and morphologically diversified in shoot systems of monocot species, focusing on the modification and co-option of GRN for leaf development.
    Frontiers in Plant Science 07/2013; 4:248. · 3.64 Impact Factor
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    ABSTRACT: • Premise of the study: On a compound leaf, leaflet primordia are repetitively formed along the apical-basal axis, with the direction varying among taxa. Why and how the directions vary among species is yet to be solved, although a change in a single factor was proposed to cause the variation. In this study, we compared two species in the Papaveraceae with different directions of leaflet initiation, Chelidonium majus subsp. asiaticum (basipetal) and Eschscholzia californica (acropetal). Because E. californica has been studied in some detail, we focused on C. majus and asked how basipetal pattern is achieved.• Methods: Since only immature leaf primordial tissue has leaflet-generating competency, we performed histological and gene expression analyses on markers of the tissue maturation state. In addition, we performed a time-course analysis of leaf primordial growth.• Key results: Quantitative reverse transcription-PCR analysis demonstrated that a putative regulator of tissue maturation in C. majus, the CINCINNATA homolog, had higher expression in apical parts than in basal parts during the organogenetic phase. In contrast, expression of the CIN homolog was not elevated in either the apical or basal parts in E. californica during the organogenetic phase.• Conclusions: In C. majus, apical parts of leaf primordia have already lost leaflet-generating competency during the organogenetic phase. We propose that precocious progression of the maturation process instructs basipetal progression of leaflet initiation in C. majus. This is not the mirror image of data on E. californica, which shows the opposite direction in leaflet formation, indicating that variation in direction is not attributable to a change in a single factor.
    American Journal of Botany 05/2013; · 2.46 Impact Factor

Publication Stats

5k Citations
638.32 Total Impact Points


  • 1992–2014
    • The University of Tokyo
      • • Department of Biological Sciences
      • • Faculty of Science and Graduate School of Science
      • • Institute of Molecular and Cellular Biosciences
      • • Laboratory of Molecular Genetics
      Tōkyō, Japan
  • 2013
    • RIKEN
      Вако, Saitama, Japan
  • 2011–2013
    • Tokyo Gakugei University
      Koganei, Tōkyō, Japan
  • 2010–2012
    • Rikkyo University
      • Department of Life Science
      Tokyo, Tokyo-to, Japan
    • Hiroshima University
      • Division of Mathematical and Life Sciences
      Hiroshima-shi, Hiroshima-ken, Japan
  • 2000–2010
    • National Institute for Basic Biology
      Okazaki, Aichi, Japan
  • 2009
    • University of Antwerp
      • Department of Biology
      Antwerpen, Flemish, Belgium
  • 2008
    • Yale University
      • Department of Molecular, Cellular and Developmental Biology
      New Haven, CT, United States
    • Yamagata University
      • Department of Biology
      Ямагата, Yamagata, Japan
  • 2007
    • Chubu University
      • College of Bioscience and Biotechnology
      Kasugai, Aichi-ken, Japan
  • 2006
    • National Institutes Of Natural Sciences
      Edo, Tōkyō, Japan
  • 2002–2006
    • The Graduate University for Advanced Studies
      • School of Advanced Sciences
      Miura, Kanagawa-ken, Japan
    • Nagoya University
      • Department of Biological Science
      Nagoya-shi, Aichi-ken, Japan
    • Bulgarian Academy of Sciences
      • Institute of Plant Physiology and Genetics
      Ulpia Serdica, Sofia-Capital, Bulgaria
  • 2003–2005
    • Tohoku University
      • Graduate School of Life Sciences
      Sendai-shi, Miyagi-ken, Japan