Graduate School of Science and Engineering（Science）
理工学専攻（分子科学）
日本語
Update date：2025/01/09
Assistant Professor
Kato Hirotaka

Affiliation

  1. Ehime UniversityGraduate School of Science and Engineering, Biology and Environmental Science助教

Research History

  1. 2015/10-2019/03Wageningen UniversityLaboratory of BiochemistryPostdoctoral researcher
  2. 2019/04-2020/03Kobe UniversityGraduate School of ScienceResearch fellow
  3. 2020/03-2021/03Kobe UniversityGraduate School of Science助手
  4. 2021/04-2022/02Kobe UniversityGraduate School of Science Division of Biology特命助教

Education

  1. Kyoto University2005/04/012009/03/31graduated
  2. Kyoto University2009/04/012011/03/31completed
  3. Kyoto University2011/04/012014/03/31withdrawn after completion of required course credits

Degree

  1. 修士（生命科学）京都大学2011/03/23
  2. 博士（生命科学）京都大学2015/05/25

Research Areas

Research Interests

  1. Auxin
  2. Evolution
  3. Marchantia polymorpha

Subject of Research

  1. Molecular mechanisms for land plant development and its evolution2009/04

Research Projects

  1. 日本学術振興会科学研究費助成事業 若手研究陸上植物に共通するオーキシン-WIP経路の多面的な発生制御の原理を探る若手研究2021/04-2024/03
  2. 日本学術振興会科学研究費助成事業 研究活動スタート支援陸上植物におけるオーキシンを介した細胞分裂面制御機構の解明研究活動スタート支援2019/08-2021/03
  3. 日本学術振興会科学研究費助成事業 特別研究員奨励費多様なオーキシン応答を引き起こす転写調節機構の基本原理特別研究員奨励費2012-2013本研究は苔類ゼニゴケをモデルにTIRI/AFB-AUX/IAA-ARF相互作用を介したオーキシン転写制御機構の有無とその役割について解析してきた。 ゼニゴケ形態形成におけるオーキシン信号伝達の役割を調べるため、ステロイドホルモン依存的にオーキシン応答を抑制できる形質転換体を作成し、様々な成長段階での表現型を解析した。その結果、MplAAを介したオーキシン応答が細胞の分化・伸長に関わり、配偶体における腹側化の促進や器官発生、胞子体の発生など生活環全体にわたって多様な現象を制御していることが示唆された。またMpIAAとMpARFs間の相互作用をBiFC法とY2H法により解析した。その結果、MpIAAとMpARFsはMpARF3同士以外のすべての組み合わせで相互作用できることが明らかになり、またそれぞれの相互作用の強度には違いがあることも明らかになった。次にMpIAAがオーキシン依存的に分解されるかどうかを調べるため、MplAAの予測分解調節領域と蛍光タンパク質の融合タンパク質発現株を作成したところ、著しくタンパク質が不安定化されていることが明らかになった。さらに、ゼニゴケにおけるオーキシン応答遺伝子をRNA-seq解析により網羅的に探索した。その結果、既知のオーキシン応答遺伝子であるMpGH3を含む152の発現変動遺伝子候補を同定した。 本研究の成果から、苔類ゼニゴケにおいてもAUX/IMの分解、AUX/IM-ARF相互作用を介した転写制御機構が保存されていることが明らかになった。またゼニゴケは他の植物種に比べて非常に単純なオーキシン信号伝達機構を用いて、様々な生理応答を制御していることも明らかになった。今後、それぞれのMpARFによる下流遺伝子の発現制御機構が研究されることで、単純な転写調節機構が複雑なオーキシン応答を生み出すメカニズムの理解が進むと期待される。
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Papers

  1. Regulation of ROP GTPase cycling between active and inactive states is essential for vegetative organogenesis in Marchantia polymorpha2024/09/10Yuuki Sakai Aki Ueno Hiroki Yonetsuka Tatsuaki Goh Hirotaka Kato Yuki Kondo Hidehiro Fukaki Kimitsune IshizakiDevelopment151/ 20Research paper (scientific journal)10.1242/dev.202928URLURL_2The Company of BiologistsABSTRACT Rho/Rac of plant (ROP) GTPases are plant-specific proteins that function as molecular switches, activated by guanine nucleotide exchange factors (GEFs) and inactivated by GTPase-activating proteins (GAPs). The bryophyte Marchantia polymorpha contains single copies of ROP (MpROP), GEFs [ROPGEF and SPIKE (SPK)] and GAPs [ROPGAP and ROP ENHANCER (REN)]. MpROP regulates the development of various tissues and organs, such as rhizoids, gemmae and air chambers. The ROPGEF KARAPPO (MpKAR) is essential for gemma initiation, but the functions of other ROP regulatory factors are less understood. This study focused on two GAPs: MpROPGAP and MpREN. Mpren single mutants showed defects in thallus growth, rhizoid tip growth, gemma development, and air-chamber formation, whereas Mpropgap mutants showed no visible abnormalities. However, Mpropgap Mpren double mutants had more severe phenotypes than the Mpren single mutants, suggesting backup roles of MpROPGAP in processes involving MpREN. Overexpression of MpROPGAP and MpREN resulted in similar gametophyte defects, highlighting the importance of MpROP activation/inactivation cycling (or balancing). Thus, MpREN predominantly, and MpROPGAP as a backup, regulate gametophyte development, likely by controlling MpROP activation in M. polymorpha.
  2. Different Impacts of Ni2+ and Li+ to Plants and Mycorrhiza Systems: Roles of Bioligands Forming Metal-Binding Complexes in Cells and Apoplasts2024/02/18Masahiro Inouhe Yui Katsuta Aki Kato Hirotaka Kato Yoh Sakuma Clemens Walther Veenu Joon Dharmendra K. GuptaLithium and Nickel Contamination in Plants and the Environment139-169(MISC) Introduction and explanation (others)10.1142/9789811283123_0006WORLD SCIENTIFIC
  3. Auxin signaling is essential for organogenesis but not for cell survival in the liverwort Marchantia polymorpha.2022/12/19Hidemasa Suzuki Hirotaka Kato Megumi Iwano Ryuichi Nishihama Takayuki KohchiThe Plant cellResearch paper (scientific journal)10.1093/plcell/koac367Auxin plays pleiotropic roles in plant development via gene regulation upon its perception by the receptors TRANSPORT INHIBITOR RESPONSE 1/AUXIN SIGNALING F-BOX (TIR1/AFBs). This auxin-regulated transcriptional control mechanism originated in the common ancestor of land plants. Although the complete loss of TIR1/AFBs causes embryonic lethality in Arabidopsis thaliana, it is unclear whether the requirement for TIR1-mediated auxin perception in cell viability can be generalized. The model liverwort Marchantia polymorpha has a minimal auxin signaling system with only a single TIR1/AFB, MpTIR1. Here we show by genetic, biochemical, and transcriptomic analyses that MpTIR1 functions as an evolutionarily conserved auxin receptor. Null mutants and conditionally knocked-out mutants of MpTIR1 were viable but incapable of forming any organs and grew as cell masses. Principal component analysis performed using transcriptomes at various developmental stages indicated that MpTIR1 is involved in the developmental transition from spores to organized thalli, during which apical notches containing stem cells are established. In Mptir1 cells, stem-cell- and differentiation-related genes were up- and down-regulated, respectively. Our findings suggest that, in M. polymorpha, auxin signaling is dispensable for cell division but is essential for three-dimensional patterning of the plant body by establishing pluripotent stem cells for organogenesis, a derived trait of land plants.
  4. R2R3-MYB transcription factor GEMMA CUP-ASSOCIATED MYB1 mediates the cytokinin signal to achieve proper organ development in Marchantia polymorpha2022/12/07Shiori S. Aki Tomoyo Morimoto Taiki Ohnishi Ayumi Oda Hirotaka Kato Kimitsune Ishizaki Ryuichi Nishihama Takayuki Kohchi Masaaki UmedaScientific Reports12/ 1Research paper (scientific journal)10.1038/s41598-022-25684-3URLURL_2Springer Science and Business Media LLCAbstract Cytokinin, a plant hormone, plays essential roles in organ growth and development. The type-B response regulator-mediated cytokinin signaling is repressed by type-A response regulators and is conserved in the liverwort Marchantia polymorpha. Its signal coordinates the development of diverse organs on the thallus body, such as the gemma cup, rhizoid, and air pores. Here we report that the type-B response regulator MpRRB upregulates the expression of the R2R3-MYB transcription factor GEMMA CUP-ASSOCIATED MYB1 (MpGCAM1) in M. polymorpha. Whereas both Mpgcam1 and Mprrb knockout mutants exhibited defects in gemma cup formation, the Mpgcam1 Mprra double mutant, in which cytokinin signaling is activated due to the lack of type-A response regulator, also formed no gemma cups. This suggests that MpGCAM1 functions downstream of cytokinin signaling. Inducible overexpression of MpGCAM1 produced undifferentiated cell clumps on the thalli of both wild-type and Mprrb. However, smaller thalli were formed in Mprrb compared to the wild-type after the cessation of overexpression. These results suggest that cytokinin signaling promotes gemma cup formation and cellular reprogramming through MpGCAM1, while cytokinin signals also participate in activating cell division during thallus development.
  5. The Renaissance and Enlightenment of Marchantia as a model system.2022/08/17John L Bowman Mario Arteaga-Vazquez Frederic Berger Liam N Briginshaw Philip Carella Adolfo Aguilar-Cruz Kevin M Davies Tom Dierschke Liam Dolan Ana E Dorantes-Acosta Tom J Fisher Eduardo Flores-Sandoval Kazutaka Futagami Kimitsune Ishizaki Rubina Jibran Takehiko Kanazawa Hirotaka Kato Takayuki Kohchi Jonathan Levins Shih-Shun Lin Hirofumi Nakagami Ryuichi Nishihama Facundo Romani Sebastian Schornack Yasuhiro Tanizawa Masayuki Tsuzuki Takashi Ueda Yuichiro Watanabe Katsuyuki T Yamato Sabine ZachgoThe Plant cell(MISC) Introduction and explanation (scientific journal)10.1093/plcell/koac219The liverwort Marchantia polymorpha has been utilized as a model for biological studies since the 18th century. In the past few decades there has been a Renaissance in its utilization in genomic and genetic approaches to investigating physiological, developmental, and evolutionary aspects of land plant biology. The reasons for its adoption are similar to those of other genetic models, e.g. simple cultivation, ready access via its worldwide distribution, ease of crossing, facile genetics, and more recently, efficient transformation, genome editing, and genomic resources. The haploid gametophyte dominant life cycle of M. polymorpha is conducive to forward genetic approaches. The lack of ancient whole-genome duplications within liverworts facilitates reverse genetic approaches, and possibly related to this genomic stability, liverworts possess sex chromosomes that evolved in the ancestral liverwort. As a representative of one of the three bryophyte lineages, its phylogenetic position allows comparative approaches to provide insights into ancestral land plants. Given the karyotype and genome stability within liverworts, the resources developed for M. polymorpha have facilitated the development of related species as models for biological processes lacking in M. polymorpha.
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Presentations

  1. Developmental roles of WIP, the evolutionarily conserved auxin-responsive transcription factorInternational Marchantia Workshop 20242024/11/18Oral presentation(general)
  2. 懸濁培養細胞とウキクサ葉状体のリチウム・ニッケルイオン集積性とリガンド生成能日本植物学会第88回大会2024/09/16Poster presentation
  3. 苔類ゼニゴケにおける気室および同化糸の形成異常株の解析日本植物学会第88回大会2024/09/16Poster presentation
  4. 苔類ゼニゴケにおける転写因子WIP 過剰発現株の解析日本植物学会第88回大会2024/09/16Poster presentation
  5. 四国における Google Map を用いたダンチクの分布調査 ―環境要因による生息地の予測 ―日本植物学会第88回大会2024/09/16Poster presentation
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Awards

  1. 2019/09UFW Research Award 2019
  2. 2013/06Journal of Plant Research Best Paper Award
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Allotted Class

  1. 2024Basic Experiments in Biology
  2. 2024Basic Experiments in Biology
  3. 2024Experiment in BiologyⅣ
  4. 2024Perspectives for Modern BiologyⅠ
  5. 2024Special Lecture on BiologyⅠ
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Professional Memberships

  1. THE JAPANESE SOCIETY OF PLANT PHYSIOLOGISTS
  2. THE BOTANICAL SOCIETY OF JAPAN
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