Updated on 2021/09/17

写真b

 
SAKAKIBARA Keiko
 
*Items subject to periodic update by Rikkyo University (The rest are reprinted from information registered on researchmap.)
Affiliation*
College of Science Department of Life Science
Graduate School of Science Field of Study: Life Science
Graduate School of Science Field of Study: Life Science
Title*
Associate Professor
Degree
博士(理学) ( 総合研究大学院大学 )
Research Theme*
  • 陸上植物は約4億7千万年以上前にシャジクモ藻類のような祖先から分かれて進化してきたと考えられている。その過程で、新しい遺伝子の獲得や、もともと持っていた遺伝子が新しい機能を獲得したことが重要な役割を果たした。陸上植物やその近縁種の持っている遺伝子の配列やその遺伝子の機能を調べて比較することで、陸上植物の成立に関わった遺伝子進化の解明をめざす。

  • Research Interests
  • 藻類

  • コケ植物

  • 植物

  • 発生進化学

  • Campus Career*
    • 4 2016 - Present 
      College of Science   Department of Life Science   Associate Professor
    • 4 2016 - Present 
      Graduate School of Science   Field of Study: Life Science   Associate Professor
    • 4 2016 - Present 
      Graduate School of Science   Field of Study: Life Science   Associate Professor
    Profile
    専門:植物の発生進化学。主にヒメツリガネゴケを用いた形態形成。
    略歴:2003年 総合研究大学院大学で学位取得後、広島大、オーストラリアMonash大にてポスドクを経て
    2009年 ERATO長谷部分化全能性プロジェクトにて技術参事、
    2011年 広島大学大学院理学研究科にて特任助教、
    2013年 東京大学大学院理学系研究科にて助教。
    2016年 立教大学理学部生命理学科にて准教授
     

    Awards

    • 8 2014  
      日本進化学会研究奨励賞  陸上植物の生活史の発生進化学的研究
       
      榊原恵子

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    • 11 2013  
      広島大学  広島大学学長表彰 
       
      榊原恵子

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    • 9 2013  
      日本植物学会  奨励賞  ヒメツリガネゴケをモデルとした発生進化学的解析による陸上植物の異形世代交代を司る分子機構の解明
       
      榊原恵子

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    Papers

    • The Hornworts: Morphology, evolution and development Peer-reviewed

      Eftychios Frangedakis, Masaki Shimamura, Juan Carlos Villarreal, Fay‐Wei Li, Marta Tomaselli, Manuel Waller, Keiko Sakakibara, Karen S. Renzaglia, Péter Szövényi

      New Phytologist   15 9 2020

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      Language:English   Publishing type:Research paper (scientific journal)   Publisher:Wiley  

      DOI: 10.1111/nph.16874

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    • Anthoceros genomes illuminate the origin of land plants and the unique biology of hornworts Peer-reviewed

      Fay-Wei Li, Tomoaki Nishiyama, Manuel Waller, Eftychios Frangedakis, Jean Keller, Zheng Li, Noe Fernandez-Pozo, Michael S. Barker, Tom Bennett, Miguel A. Blázquez, Shifeng Cheng, Andrew C. Cuming, Jan de Vries, Sophie de Vries, Pierre-Marc Delaux, Issa S. Diop, C. Jill Harrison, Duncan Hauser, Jorge Hernández-García, Alexander Kirbis, John C. Meeks, Isabel Monte, Sumanth K. Mutte, Anna Neubauer, Dietmar Quandt, Tanner Robison, Masaki Shimamura, Stefan A. Rensing, Juan Carlos Villarreal, Dolf Weijers, Susann Wicke, Gane K.-S. Wong, Keiko Sakakibara, Péter Szövényi

      Nature Plants6 ( 3 ) 259 - 272   3 2020

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      Publishing type:Research paper (scientific journal)   Publisher:Springer Science and Business Media LLC  

      DOI: 10.1038/s41477-020-0618-2

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      Other Link: http://www.nature.com/articles/s41477-020-0618-2

    • Transcription factor DUO1 generated by neo-functionalization is associated with evolution of sperm differentiation in plants Peer-reviewed

      Asuka Higo, Tomokazu Kawashima, Michael Borg, Mingmin Zhao, Irene López-Vidriero, Hidetoshi Sakayama, Sean A. Montgomery, Hiroyuki Sekimoto, Dieter Hackenberg, Masaki Shimamura, Tomoaki Nishiyama, Keiko Sakakibara, Yuki Tomita, Taisuke Togawa, Kan Kunimoto, Akihisa Osakabe, Yutaka Suzuki, Katsuyuki T. Yamato, Kimitsune Ishizaki, Ryuichi Nishihama, Takayuki Kohchi, José M. Franco-Zorrilla, David Twell, Frédéric Berger, Takashi Araki

      Nature Communications9 ( 1 ) 5283   12 2018

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      Language:English   Publishing type:Research paper (scientific journal)   Publisher:Springer Science and Business Media LLC  

      DOI: 10.1038/s41467-018-07728-3

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      Other Link: http://www.nature.com/articles/s41467-018-07728-3

    • Class III HD-Zip activity coordinates leaf development in Physcomitrella patens Peer-reviewed

      Hoichong Karen Yip, Sandra K. Floyd, Keiko Sakakibara, John L. Bowman

      DEVELOPMENTAL BIOLOGY419 ( 1 ) 184 - 197   11 2016

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      Language:English   Publishing type:Research paper (scientific journal)   Publisher:ACADEMIC PRESS INC ELSEVIER SCIENCE  

      Land plant bodies develop from meristems, groups of pluripotent stem cells, which may persist throughout the life of a plant or, alternatively, have a transitory existence. Early diverging land plants exhibit indeterminate (persistent) growth in their haploid gametophytic generation, whereas later diverging lineages exhibit indeterminate growth in their diploid sporophytic generation, raising the question of whether genetic machinery directing meristematic functions was co-opted between generations. Class III HD-Zip (C3HDZ) genes are required for the establishment and maintenance of shoot apical meristems in flowering plants. We demonstrate that in the moss Physcomitrella patens, C3HDZ genes are expressed in transitory meristems in both the gametophytic and sporophytic generations, but not in the persistent shoot meristem of the gametyphyte. Loss-of-function of P. patens C3HDZ was engineered using ectopic expression of miR166, an endogenous regulator of C3HDZ gene activity. Loss of C3HDZ gene function impaired the function of gametophytic transitory meristematic activity but did not compromise the functioning of the persistent shoot apical meristem during the gametophyte generation. These results argue against a wholesale co-option of meristematic gene regulatory networks from the gametophyte to the sporophyte during land plant evolution, instead suggesting that persistent meristems with a single apical cell in P. patens and persistent complex meristems in flowering plants are regulated by different genetic programs. (C) 2016 Elsevier Inc. All rights reserved.

      DOI: 10.1016/j.ydbio.2016.01.012

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    • Evolution in the Cycles of Life Invited Peer-reviewed

      John L. Bowman, Keiko Sakakibara, Chihiro Furumizu, Tom Dierschke

      ANNUAL REVIEW OF GENETICS, VOL 5050   133 - 154   2016

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      Language:English   Publishing type:Part of collection (book)   Publisher:ANNUAL REVIEWS  

      The life cycles of eukaryotes alternate between haploid and diploid phases, which are initiated by meiosis and gamete fusion, respectively. In both ascomycete and basidiomycete fungi and chlorophyte algae, the haploid-to-diploid transition is regulated by a pair of paralogous homeodomain protein encoding genes. That a common genetic program controls the haploid-to-diploid transition in phylogenetically disparate eukaryotic lineages suggests this may be the ancestral function for homeodomain proteins. Multicellularity has evolved independently in many eukaryotic lineages in either one or both phases of the life cycle. Organisms, such as land plants, exhibiting a life cycle whereby multicellular bodies develop in both the haploid and diploid phases are often referred to as possessing an alternation of generations. We review recent progress on understanding the genetic basis for the land plant alternation of generations and highlight the roles that homeodomain-encoding genes may have played in the evolution of complex multicellularity in this lineage.

      DOI: 10.1146/annurev-genet-120215-035227

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    • Technological Innovations Give Rise to a New Era of Plant Evolutionary Developmental Biology Peer-reviewed

      K. Sakakibara

      GENOMES AND EVOLUTION OF CHAROPHYTES, BRYOPHYTES, LYCOPHYTES AND FERNS78   3 - 35   2016

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      Authorship:Corresponding author   Language:English   Publishing type:Part of collection (book)   Publisher:ACADEMIC PRESS LTD-ELSEVIER SCIENCE LTD  

      Land plants evolved from freshwater algaelike ancestors approximately 480 million years ago. Land plants developed many new morphological features during the evolution including the origin of a multicellular diploid sporophyte, a sporophytic apical meristem that produces complex body architecture, stomata and the production of lateral organs (leaves), vascular tissue, roots, seeds and flowers. Genetic changes drove the development of these morphological features and recent technological innovations in genomics and genetic modification technologies have allowed us to investigate these genetic changes. Here, I describe recent research on several transcription factors that contributed to the morphological evolution of land plants, including the homeodomain proteins KNOX, BELL and WOX, as well as transcription factors of the bHLH, NAC and FLO/LFY families. I also discuss the conservation of plant hormone signalling, which acts to coordinate the multicellular body plan.

      DOI: 10.1016/bs.abr.2016.01.001

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    • Antagonistic Roles for KNOX1 and KNOX2 Genes in Patterning the Land Plant Body Plan Following an Ancient Gene Duplication Peer-reviewed

      Chihiro Furumizu, John Paul Alvarez, Keiko Sakakibara, John L. Bowman

      PLOS GENETICS11 ( 2 ) ee1004980   2 2015

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      Language:English   Publishing type:Research paper (scientific journal)   Publisher:PUBLIC LIBRARY SCIENCE  

      Neofunctionalization following gene duplication is thought to be one of the key drivers in generating evolutionary novelty. A gene duplication in a common ancestor of land plants produced two classes of KNOTTED-like TALE homeobox genes, class I (KNOX1) and class II (KNOX2). KNOX1 genes are linked to tissue proliferation and maintenance of meri-stematic potentials of flowering plant and moss sporophytes, and modulation of KNOX1 activity is implicated in contributing to leaf shape diversity of flowering plants. While KNOX2 function has been shown to repress the gametophytic (haploid) developmental program during moss sporophyte (diploid) development, little is known about KNOX2 function in flowering plants, hindering syntheses regarding the relationship between two classes of KNOX genes in the context of land plant evolution. Arabidopsis plants harboring loss-of-function KNOX2 alleles exhibit impaired differentiation of all aerial organs and have highly complex leaves, phenocopying gain-of-function KNOX1 alleles. Conversely, gain-of-function KNOX2 alleles in conjunction with a presumptive heterodimeric BELL TALE homeobox partner suppressed SAM activity in Arabidopsis and reduced leaf complexity in the Arabidopsis relative Cardamine hirsuta, reminiscent of loss-of-function KNOX1 alleles. Little evidence was found indicative of epistasis or mutual repression between KNOX1 and KNOX2 genes. KNOX proteins heterodimerize with BELL TALE homeobox proteins to form functional complexes, and contrary to earlier reports based on in vitro and heterologous expression, we find high selectivity between KNOX and BELL partners in vivo. Thus, KNOX2 genes confer opposing activities rather than redundant roles with KNOX1 genes, and together they act to direct the development of all above-ground organs of the Arabidopsis sporophyte. We infer that following the KNOX1/KNOX2 gene duplication in an ancestor of land plants, neofunctionalization led to evolution of antagonistic biochemical activity thereby facilitating the evolution of more complex sporophyte transcriptional networks, providing plasticity for the morphological evolution of land plant body plans.

      DOI: 10.1371/journal.pgen.1004980

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    • WOX13-like genes are required for reprogramming of leaf and protoplast cells into stem cells in the moss Physcomitrella patens Peer-reviewed

      Keiko Sakakibara, Pascal Reisewitz, Tsuyoshi Aoyama, Thomas Friedrich, Sayuri Ando, Yoshikatsu Sato, Yosuke Tamada, Tomoaki Nishiyama, Yuji Hiwatashi, Tetsuya Kurata, Masaki Ishikawa, Hironori Deguchi, Stefan A. Rensing, Wolfgang Werr, Takashi Murata, Mitsuyasu Hasebe, Thomas Laux

      DEVELOPMENT141 ( 8 ) 1660 - 1670   4 2014

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      Language:English   Publishing type:Research paper (scientific journal)   Publisher:COMPANY OF BIOLOGISTS LTD  

      Many differentiated plant cells can dedifferentiate into stem cells, reflecting the remarkable developmental plasticity of plants. In the moss Physcomitrella patens, cells at the wound margin of detached leaves become reprogrammed into stem cells. Here, we report that two paralogous P. patens WUSCHEL-related homeobox 13-like ( PpWOX13L) genes, homologs of stem cell regulators in flowering plants, are transiently upregulated and required for the initiation of cell growth during stem cell formation. Concordantly, Delta ppwox13l deletion mutants fail to upregulate genes encoding homologs of cell wall loosening factors during this process. During the moss life cycle, most of the Delta ppwox13l mutant zygotes fail to expand and initiate an apical stem cell to form the embryo. Our data show that PpWOX13L genes are required for the initiation of cell growth specifically during stem cell formation, in analogy to WOX stem cell functions in seed plants, but using a different cellular mechanism.

      DOI: 10.1242/dev.097444

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    • Evolution of the Class IV HD-Zip Gene Family in Streptophytes Peer-reviewed

      Christopher S. Zalewski, Sandra K. Floyd, Chihiro Furumizu, Keiko Sakakibara, Dennis W. Stevenson, John L. Bowman

      MOLECULAR BIOLOGY AND EVOLUTION30 ( 10 ) 2347 - 2365   10 2013

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      Language:English   Publishing type:Research paper (scientific journal)   Publisher:OXFORD UNIV PRESS  

      Class IV homeodomain leucine zipper (C4HDZ) genes are plant-specific transcription factors that, based on phenotypes in Arabidopsis thaliana, play an important role in epidermal development. In this study, we sampled all major extant lineages and their closest algal relatives for C4HDZ homologs and phylogenetic analyses result in a gene tree that mirrors land plant evolution with evidence for gene duplications in many lineages, but minimal evidence for gene losses. Our analysis suggests an ancestral C4HDZ gene originated in an algal ancestor of land plants and a single ancestral gene was present in the last common ancestor of land plants. Independent gene duplications are evident within several lineages including mosses, lycophytes, euphyllophytes, seed plants, and, most notably, angiosperms. In recently evolved angiosperm paralogs, we find evidence of pseudogenization via mutations in both coding and regulatory sequences. The increasing complexity of the C4HDZ gene family through the diversification of land plants correlates to increasing complexity in epidermal characters.

      DOI: 10.1093/molbev/mst132

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    • KNOX2 Genes Regulate the Haploid-to-Diploid Morphological Transition in Land Plants Peer-reviewed

      Keiko Sakakibara, Sayuri Ando, Hoichong Karen Yip, Yosuke Tamada, Yuji Hiwatashi, Takashi Murata, Hironori Deguchi, Mitsuyasu Hasebe, John L. Bowman

      SCIENCE339 ( 6123 ) 1067 - 1070   3 2013

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      Authorship:Corresponding author   Language:English   Publishing type:Research paper (scientific journal)   Publisher:AMER ASSOC ADVANCEMENT SCIENCE  

      Unlike animals, land plants undergo an alternation of generations, producing multicellular bodies in both haploid (1n: gametophyte) and diploid (2n: sporophyte) generations. Plant body plans in each generation are regulated by distinct developmental programs initiated at either meiosis or fertilization, respectively. In mosses, the haploid gametophyte generation is dominant, whereas in vascular plants-including ferns, gymnosperms, and angiosperms-the diploid sporophyte generation is dominant. Deletion of the class 2 KNOTTED1-LIKE HOMEOBOX (KNOX2) transcription factors in the moss Physcomitrella patens results in the development of gametophyte bodies from diploid embryos without meiosis. Thus, KNOX2 acts to prevent the haploid-specific body plan from developing in the diploid plant body, indicating a critical role for the evolution of KNOX2 in establishing an alternation of generations in land plants.

      DOI: 10.1126/science.1230082

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    • Gametangia development in the moss Physcomitrella patens. Peer-reviewed

      Kofuji R, Yoshimura T, Inoue H, Sakakibara K, Hiwatashi Y, Kurt T, Aoyama T, Ueda K, Hasebe N

      Annual Plant Reviews, Volume36 The moss <i>Physcomitrella patens</i>36   167 - 181   6 2009

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    • Class 1 KNOX genes are not involved in shoot development in the moss Physcomitrella patens but do function in sporophyte development Peer-reviewed

      Keiko Sakakibara, Tomoaki Nishiyama, Hironori Deguchi, Mitsuyasu Hasebe

      EVOLUTION & DEVELOPMENT10 ( 5 ) 555 - 566   9 2008

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      Language:English   Publishing type:Research paper (scientific journal)   Publisher:WILEY-BLACKWELL  

      Although the number and form of metazoan organs are determined in the embryo, plants continuously form organs via pluripotent stem cells contained within the meristem. Flowering plants have an indeterminate meristem in their diploid generation, whereas the common ancestor of land plants is inferred to have formed an indeterminate meristem in its haploid generation, as observed in the extant basal land plants, bryophytes, including mosses. It is hypothesized that the underlying gene networks for the diploid meristem were initially present in the haploid generation of the basal land plants and were eventually co-opted for expression in the diploid generation. In flowering plants, the class 1 KNOTTED1-LIKE HOMEOBOX (KNOX) transcription factors are essential for the function of the indeterminate apical meristem. Here, we show that the class 1 KNOX orthologs function in the diploid organ, with determinate growth in the moss Physcomitrella patens, but do not function in the haploid indeterminate meristem. We propose that the genetic networks governing the indeterminate meristem in land plants are variable, and the networks governing the diploid indeterminate meristem with the class 1 KNOX genes likely evolved de novo in the flowering plant lineage.

      DOI: 10.1111/j.1525-142X.2008.00271.x

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    • The Physcomitrella genome reveals evolutionary insights into the conquest of land by plants Peer-reviewed

      Stefan A. Rensing, Daniel Lang, Andreas D. Zimmer, Astrid Terry, Asaf Salamov, Harris Shapiro, Tomoaki Nishiyama, Pierre-Francois Perroud, Erika A. Lindquist, Yasuko Kamisugi, Takako Tanahashi, Keiko Sakakibara, Tomomichi Fujita, Kazuko Oishi, Tadasu Shin-I, Yoko Kuroki, Atsushi Toyoda, Yutaka Suzuki, Shin-ichi Hashimoto, Kazuo Yamaguchi, Sumio Sugano, Yuji Kohara, Asao Fujiyama, Aldwin Anterola, Setsuyuki Aoki, Neil Ashton, W. Brad Barbazuk, Elizabeth Barker, Jeffrey L. Bennetzen, Robert Blankenship, Sung Hyun Cho, Susan K. Dutcher, Mark Estelle, Jeffrey A. Fawcett, Heidrun Gundlach, Kousuke Hanada, Alexander Heyl, Karen A. Hicks, Jon Hughes, Martin Lohr, Klaus Mayer, Alexander Melkozernov, Takashi Murata, David R. Nelson, Birgit Pils, Michael Prigge, Bernd Reiss, Tanya Renner, Stephane Rombauts, Paul J. Rushton, Anton Sanderfoot, Gabriele Schween, Shin-Han Shiu, Kurt Stueber, Frederica L. Theodoulou, Hank Tu, Yves Van de Peer, Paul J. Verrier, Elizabeth Waters, Andrew Wood, Lixing Yang, David Cove, Andrew C. Cuming, Mitsuyasu Hasebe, Susan Lucas, Brent D. Mishler, Ralf Reski, Igor V. Grigoriev, Ralph S. Quatrano, Jeffrey L. Boore

      SCIENCE319 ( 5859 ) 64 - 69   1 2008

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      Language:English   Publishing type:Research paper (scientific journal)   Publisher:AMER ASSOC ADVANCEMENT SCIENCE  

      We report the draft genome sequence of the model moss Physcomitrella patens and compare its features with those of flowering plants, from which it is separated by more than 400 million years, and unicellular aquatic algae. This comparison reveals genomic changes concomitant with the evolutionary movement to land, including a general increase in gene family complexity; loss of genes associated with aquatic environments ( e. g., flagellar arms); acquisition of genes for tolerating terrestrial stresses ( e. g., variation in temperature and water availability); and the development of the auxin and abscisic acid signaling pathways for coordinating multicellular growth and dehydration response. The Physcomitrella genome provides a resource for phylogenetic inferences about gene function and for experimental analysis of plant processes through this plant&apos;s unique facility for reverse genetics.

      DOI: 10.1126/science.1150646

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    • Green genes - Comparative genomics of the green branch of life Peer-reviewed

      John L. Bowman, Sandra K. Floyd, Keiko Sakakibara

      CELL129 ( 2 ) 229 - 234   4 2007

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      Language:English   Publishing type:Research paper (scientific journal)   Publisher:CELL PRESS  

      As more plant genome sequences become available, researchers are increasingly using comparative genomics to address some of the major questions in plant biology. Such questions include the evolution of photosynthesis and multicellularity, the developmental genetic changes responsible for alterations in body plan, and the origin of important plant innovations such as roots, leaves, and vascular tissue.

      DOI: 10.1016/j.cell.2007.04.004

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    • KNOX homeobox genes potentially have similar function in both diploid unicellular and multicellular meristems, but not in haploid meristems Peer-reviewed

      R Sano, CM Juarez, B Hass, K Sakakibara, M Ito, JA Banks, M Hasebe

      EVOLUTION & DEVELOPMENT7 ( 1 ) 69 - 78   1 2005

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      Language:English   Publishing type:Research paper (scientific journal)   Publisher:BLACKWELL PUBLISHING INC  

      Members of the class 1 knotted-like homeobox (KNOX) gene family are important regulators of shoot apical meristem development in angiosperms. To determine whether they function similarly in seedless plants, three KNOX genes (two class 1 genes and one class 2 gene) from the fern Ceratopteris richardii were characterized. Expression of both class 1 genes was detected in the shoot apical cell, leaf primordia, marginal part of the leaves, and vascular bundles by in situ hybridization, a pattern that closely resembles that of class 1 KNOX genes in angiosperms with compound leaves. The fern class 2 gene was expressed in all sporophyte tissues examined, which is characteristic of class 2 gene expression in angiosperms. All three CRKNOX genes were not detected in gametophyte tissues by RNA gel blot analysis. Arabidopsis plants overexpressing the fern class 1 genes resembled plants that overexpress seed plant class 1 KNOX genes in leaf morphology. Ectopic expression of the class 2 gene in Arabidopsis did not result in any unusual phenotypes. Taken together with phylogenetic analysis, our results suggest that (a) the class 1 and 2 KNOX genes diverged prior to the divergence of fern and seed plant lineages, (b) the class 1 KNOX genes function similarly in seed plant and fern sporophyte meristem development despite their differences in structure, (c) KNOX gene expression is not required for the development of the fern gametophyte, and (d) the sporophyte and gametophyte meristems of ferns are not regulated by the same developmental mechanisms at the molecular level.

      DOI: 10.1111/j.1525-142X.2005.05008.x

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    • Involvement of auxin and a homeodomain-leucine zipper I gene in rhizoid development of the moss Physcomitrella patens Peer-reviewed

      K Sakakibara, T Nishiyama, N Sumikawa, R Kofuji, T Murata, M Hasebe

      DEVELOPMENT130 ( 20 ) 4835 - 4846   10 2003

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      Language:English   Publishing type:Research paper (scientific journal)   Publisher:COMPANY OF BIOLOGISTS LTD  

      Differentiation of epidermal cells is important for plants because they are in direct contact with the environment. Rhizoids are multicellular filaments that develop from the epidermis in a wide range of plants, including pteridophytes, bryophytes, and green algae; they have similar functions to root hairs in vascular plants in that they support the plant body and are involved in water and nutrient absorption. In this study, we examined mechanisms underlying rhizoid development in the moss, Physcomitrella patens, which is the only land plant in which high-frequency gene targeting is possible. We found that rhizoid development can be split into two processes: determination and differentiation. Two types of rhizoids with distinct developmental patterns (basal and mid-stem rhizoids) were recognized. The development of basal rhizoids from epidermal cells was induced by exogenous auxin, while that of mid-stem rhizoids required an unknown factor in addition to exogenous auxin. Once an epidermal cell had acquired a rhizoid initial cell fate, expression of the homeodomain-leucine zipper I gene Pphb7 was induced. Analysis of Pphb7 disruptant lines showed that Pphb7 affects the induction of pigmentation and the increase in the number and size of chloroplasts, but not the position or number of rhizoids. This is the first report on the involvement of a homeodomain-leucine zipper I gene in epidermal cell differentiation.

      DOI: 10.1242/dev.00644

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    • Characterization of a FLORICAULA/LEAFY homologue of Gnetum parvifolium and its implications for the evolution of reproductive organs in seed plants Peer-reviewed

      S Shindo, K Sakakibara, R Sano, K Ueda, M Hasebe

      INTERNATIONAL JOURNAL OF PLANT SCIENCES162 ( 6 ) 1199 - 1209   11 2001

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      Language:English   Publishing type:Research paper (scientific journal)   Publisher:UNIV CHICAGO PRESS  

      The morphological variation among reproductive organs of extant seed plants makes assessment of organ homology difficult. Comparisons of expression patterns of homeotic genes that control organ development will yield new information about the homology of organs to assess inferences deduced from previous morphological studies. In angiosperms, the FLORICAULA/LEAFY (FLO/LFY) genes convert a vegetative shoot meristem to a floral meristem by inducing floral homeotic genes, most of which belong to the MADS-box gene family. To provide insights into the evolution of reproductive organs in seed plants, a FLO/LFY homologue (GpLFY) was cloned from Gnetum parvifolium. GpLFY mRNA was expressed in both the vegetative shoot apex and the female strobilus. The GpLFY mRNA signal was detected in early developmental stages of the collar and the ovule primordium, including the nucellus and three envelopes. A comparison of FLO/LFY gene expression in Gnetum and the conifer Pinus radiata indicates that the Gnetum collar and ovule are homologous with the conifer bract and ovule-ovuliferous scale complex, respectively. Overexpression of GpLFY in transgenic Arabidopsis promoted a conversion of a shoot meristem to a floral primordium. The Arabidopsis LFY null mutant, lfy-26, with a malformed flower, was complemented by overexpression of GpLFY. These results indicate that the inductive pathway from the FLO/LFY gene to the MADS-box genes already existed in the common ancestor of angiosperms and gymnosperms.

      DOI: 10.1086/323417

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    • Isolation of homeodomain-leucine zipper genes from the moss Physcomitrella patens and the evolution of homeodomain-leucine zipper genes in land plants Peer-reviewed

      K. Sakakibara, T. Nishiyama, M. Kato, M. Hasebe

      Molecular Biology and Evolution18 ( 4 ) 491 - 502   2001

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      Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)   Publisher:Society for Molecular Biology and Evolution  

      Homeobox genes encode transcription factors involved in many aspects of developmental processes. The homeodomain-leucine zipper (HD-Zip) genes, which are characterized by the presence of both a homeodomain and a leucine zipper motif, form a clade within the homeobox superfamily and were previously reported only from vascular plants. Here we report the isolation of 10 HD-Zip genes (named Pphb1-Pphb10) from the moss Physcomitrella patens. Based on a phylogenetic analysis of the 10 Pphb genes and previously reported vascular plant HD-Zip genes, all of the Pphb genes except Pphb3 belong to three of the four HD-Zip subfamilies (HD-Zip I, II, and III), indicating that these subfamilies originated before the divergence of the vascular plant and moss lineages. Pphb3 is sister to the HD-Zip II subfamily and has some distinctive characteristics, including the difference of the a1 and d1 sites of its leucine zipper motif, which are well conserved in each HD-Zip subfamily. Comparison of the genetic divergence of representative HD-Zip I and II genes showed that the evolutionary rate of HD-Zip I genes was faster than that of HD-Zip II genes.

      DOI: 10.1093/oxfordjournals.molbev.a003828

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    • Tagged mutagenesis and gene-trap in the moss, Physcomitrella patens by shuttle mutagenesis Peer-reviewed

      Tomoaki Nishiyama, Yuji Hiwatashi, Keiko Sakakibara, Masahiro Kato, Mitsuyasu Hasebe

      DNA Research7 ( 1 ) 9 - 17   2000

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      Language:English   Publishing type:Research paper (scientific journal)   Publisher:Universal Academy Press Inc.  

      The moss, Physcomitrella patens has been used as a useful material in many fields, because of its simple body plan, ease of gene targeting, and other reasons. Although many mutants have been reported, no method to isolate the corresponding genes was reported. We developed a gene tagging and gene-trap system in P. patens by using the shuttle mutagenesis technique, which has been used in the budding yeast. In 5264 tagged lines, 203 mutants with altered developmental or morphological phenotypes were obtained. In 129 of 4757 gene-trap lines, β-glucuronidase (GUS) activity was detected in some tissue. Although multiple copies of a tag were detected in many tagged lines by Southern analyses, most copies are likely integrated at the same locus according to PCR analyses.

      DOI: 10.1093/dnares/7.1.9

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    Misc.

    • 古い酒を新しい革袋に~preexisting gene regulatory network の転用による 陸上植物のボディプラン革新 Invited Peer-reviewed

      ISHIZAKI KIMITSUNE, SAKAKIBARA KEIKO

      BSJ-Review7   47 - 54   4 2016

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      Language:Japanese   Publishing type:Article, review, commentary, editorial, etc. (scientific journal)   Publisher:日本植物学会  

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    • Functional analyses of class 2 KNOX genes in Physcomitrella patens

      K Sakakibara, H Deguchi, M Hasebe

      PLANT AND CELL PHYSIOLOGY47   S180 - S180   2006

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      Language:English   Publishing type:Research paper, summary (international conference)   Publisher:OXFORD UNIV PRESS  

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    • Functional analysis of class 1 KNOX genes in Physcomitrella patens

      T Nishiyama, K Sakakibara, M Hasebe

      PLANT AND CELL PHYSIOLOGY46   S198 - S198   2005

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      Language:English   Publishing type:Research paper, summary (international conference)   Publisher:OXFORD UNIV PRESS  

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    • Functional Analysis of KNOX class 1 genes in Physcomitrella patens

      T Nishiyama, K Sakakibara, M Hasebe

      PLANT AND CELL PHYSIOLOGY45   S162 - S162   2004

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      Language:English   Publishing type:Research paper, summary (international conference)   Publisher:OXFORD UNIV PRESS  

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    • コケ植物, ニセツリガネゴケにおけるMADS遺伝子の単離と遺伝子ターゲティングによる機能解析

      小藤 累美子, 榊原 恵子, 西山 智明, 長谷部 光泰

      日本分子生物学会年会プログラム・講演要旨集21   1 12 1998

    • Physcomiterella patensにおけるホメオボックス遺伝子の単離と解析

      榊原 恵子, 西山 智明, 小藤 累美子, 加藤 雅啓, 長谷部 光泰

      日本植物学会大会研究発表記録 = Proceedings of the annual meeting of the Botanical Society of Japan62   1 9 1998

    • Physcomitrella patensにおけるMADS遺伝子の単離と解析

      小藤 累美子, 榊原 恵子, 西山 智明, 長谷部 光泰

      日本植物学会大会研究発表記録 = Proceedings of the annual meeting of the Botanical Society of Japan62   1 9 1998

    • Physcomitrella patensのタグつき変異体ライブラリーの作成

      西山 智明, 榊原 恵子, 小藤 累美子, 加藤 雅啓, 長谷部 光泰

      日本植物学会大会研究発表記録 = Proceedings of the annual meeting of the Botanical Society of Japan62   1 9 1998

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      SOCIETY OF EVOLUTIONARY STUDIES

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      THE BOTANICAL SOCIETY OF JAPAN

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