Details of the Researcher

PHOTO

Kenji Nishizawa
Section
Graduate School of Science
Job title
Specially Appointed Assistant Professor(Research)
Degree

  • Phd (Kyushu University)

Research History 3

  • 2023/05 - 2024/09
    東京大学大学院理学系研究科物理学専攻

  • 2019/03 - 2023/03
    CNRS/ The Developmental Biology Institute of Marseille (IBDM)

  • 2018/04 - 2019/02
    九州大学大学院理学府物理学専攻

Education 1

  • 九州大学大学院　理学府　物理学専攻 博士課程

    2015/04 - 2018/03

Committee Memberships 1

  • 日本機械学会　バイオエンジニアリング(BE)部門次世代委員会・委員

    2024/05 - Present

Research Areas 2

  • Natural sciences / Bio-, chemical, and soft-matter physics /

  • Life sciences / Biophysics /

Awards 1

  1. 九州大学学生表彰

    2018/03

Papers 14

  1. Two-point optical manipulation reveals mechanosensitive remodeling of cell-cell contacts in vivo. International-journal

    Kenji Nishizawa, Shao-Zhen Lin, Claire Chardès, Jean-François Rupprecht, Pierre-François Lenne

    Proceedings of the National Academy of Sciences of the United States of America　120　(13)　e2212389120　2023/03/28

    DOI： 10.1073/pnas.2212389120 　

    More details Close

    Biological tissues acquire reproducible shapes during development through dynamic cell behaviors. Most of these behaviors involve the remodeling of cell-cell contacts. During epithelial morphogenesis, contractile actomyosin networks remodel cell-cell contacts by shrinking and extending junctions between lateral cell surfaces. However, actomyosin networks not only generate mechanical stresses but also respond to them, confounding our understanding of how mechanical stresses remodel cell-cell contacts. Here, we develop a two-point optical manipulation method to impose different stress patterns on cell-cell contacts in the early epithelium of the Drosophila embryo. The technique allows us to produce junction extension and shrinkage through different push and pull manipulations at the edges of junctions. We use these observations to expand classical vertex-based models of tissue mechanics, incorporating negative and positive mechanosensitive feedback depending on the type of remodeling. In particular, we show that Myosin-II activity responds to junction strain rate and facilitates full junction shrinkage. Altogether our work provides insight into how stress produces efficient deformation of cell-cell contacts in vivo and identifies unanticipated mechanosensitive features of their remodeling.

  2. Universal glass-forming behavior of in vitro and living cytoplasm

    Kenji Nishizawa, Kei Fujiwara, Masahiro Ikenaga, Nobushige Nakajo, Miho Yanagisawa, Daisuke Mizuno

    SCIENTIFIC REPORTS　7　2017/11

    DOI： 10.1038/s41598-017-14883-y 　

    ISSN： 2045-2322

  3. Feedback-tracking microrheology in living cells

    Kenji Nishizawa, Marcel Bremerich, Heev Ayade, Christoph F. Schmidt, Takayuki Ariga, Daisuke Mizuno

    SCIENCE ADVANCES　3　(9)　2017/09

    DOI： 10.1126/sciadv.1700318 　

    ISSN： 2375-2548

  4. Single power-law rheology of crowded cytoplasm in living cells

    Hiroyuki Ebata, Kenji Nishizawa, Fransisca A.S. van Esterik, Tetsushi Maeda, Yuki Tao, Shono Inokuchi, Hirohiko Ise, Daisuke Mizuno

    Cell Reports Physical Science　7　(1)　103059-103059　2026/01

    Publisher: Elsevier BV

    DOI： 10.1016/j.xcrp.2025.103059 　

    ISSN： 2666-3864

  5. Activity-dependent glassy cell mechanics II: Non-thermal fluctuations under metabolic activity

    Katsuhiro Umeda, Kenji Nishizawa, Wataru Nagao, Shono Inokuchi, Yujiro Sugino, Hiroyuki Ebata, Daisuke Mizuno

    Biophysical Journal　2023/10

    Publisher: Elsevier BV

    DOI： 10.1016/j.bpj.2023.10.018 　

    ISSN： 0006-3495

  6. Measuring fluctuating dynamics of sparsely crosslinked actin gels with dual-feedback nonlinear microrheology

    Kenji Nishizawa, Natsuki Honda, Shono Inokuchi, Hiroyuki Ebata, Takayuki Ariga, Daisuke Mizuno

    Physical Review E　108　(3)　2023/09/06

    Publisher: American Physical Society (APS)

    DOI： 10.1103/physreve.108.034601 　

    ISSN： 2470-0045

    eISSN： 2470-0053

  7. Activity-dependent glassy cell mechanics Ⅰ: Mechanical properties measured with active microrheology

    Hiroyuki Ebata, Katsuhiro Umeda, Kenji Nishizawa, Wataru Nagao, Shono Inokuchi, Yujiro Sugino, Takafumi Miyamoto, Daisuke Mizuno

    Biophysical Journal　122　(10)　1781-1793　2023/05

    Publisher: Elsevier BV

    DOI： 10.1016/j.bpj.2023.04.011 　

    ISSN： 0006-3495

  8. Two-Point Optical Manipulation of Cell Junctions in the Early Epithelium of the Drosophila Embryo. International-journal

    Kenji Nishizawa, Claire Chardès, Raphaël Clément, Pierre-François Lenne

    Methods in molecular biology (Clifton, N.J.)　2600　107-118　2023

    DOI： 10.1007/978-1-0716-2851-5_7 　

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    Laser manipulation is widely used to study mechanics from the molecular to the tissue scale. We implemented optical tweezers to directly manipulate single cell-cell junctions in a developing tissue. We further extended the approach to two-point laser manipulation to enable extensive remodeling of cell-cell junctions. Here, we describe two-point laser manipulation and its implementation to probe the mechanics of cell junctions in the Drosophila embryo.

  9. Feedback Microrheology in Soft Matter

    Kenji Nishizawa, Natsuki Honda, Masahiro Ikenaga, Shono Inokuchi, Yujiro Sugino, Takayuki Arigac, Daisuke Mizuno

    2021/06/09

    Publisher: arXiv

    DOI： 10.48550/ARXIV.2106.05119 　

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    Soft matter consists of meso-scale (nm~{\mu}m) structures that are formed by weak interactions and reorganized under thermal fluctuations. The resulting complex relaxation phenomena may be probed with microrheology, by observing the movement of embedded probe particles. Because of the softness of the material, however, perturbations to the probe that are inevitably added during microrheology experiments prevent direct translation of those movements to rheological properties. In this study, we conducted optical-trap-based microrheology with significantly reduced mechanical perturbations; dual feedback technology allowed us to apply well-determined optical-trapping forces to a fluctuating embedded probe and precisely measure its response and fluctuations with high spatiotemporal resolution. We demonstrate the improved performance of this technique by studying an reconstituted network of actin cytoskeletal filaments, observing their slow dynamics, homogeneous thermal fluctuations as well as activated hopping between mesoscale microenvironments.

  10. Glassy cytoplasm driven by non-thermal forces

    Kenji Nishizawa, Daisuke Mizuno

    BIORHEOLOGY　58　(3-4)　156-156　2021

    ISSN： 0006-355X

    eISSN： 1878-5034

  11. Metabolism-dependent active diffusion in living cells

    Yujiro Sugino, Kenji Nishizawa, Daisuke Mizuno

    BIORHEOLOGY　58　(3-4)　157-157　2021

    ISSN： 0006-355X

    eISSN： 1878-5034

  12. Optical trap and laser interferometry in living cells

    Daisuke Mizuno, Umeda Katsuhiro, Sugino Yujiro, Kenji Nishizawa

    Proceedings of SPIE - The International Society for Optical Engineering　11140　2019

    Publisher: SPIE

    ISSN： 1996-756X 0277-786X

  13. 3P196 Crowding effects on viscoelastic properties in cell model systems(Cell biology,Poster,The 52th Annual Meeting of the Biophysical Society of Japan(BSJ2014))

    Kenji Nishizawa, Kei Fujiwara, Nobushige Nakajo, Miho Yanagisawa, Daisuke Mizuno

    Seibutsu Butsuri　54　(1)　S281　2014

    Publisher: The Biophysical Society of Japan General Incorporated Association

    DOI： 10.2142/biophys.54.S281_4 　

  14. 2P218 Generation of artificial cells that mimic living cells(13B. Biological & Artifical membrane: Dynamics,Poster)

    Fujiwara Kei, Nishizawa Kenji, Yanagisawa Miho, Nomura Shin-ichiro M., Mizuno Daisuke

    Seibutsu Butsuri　53　(1)　S195　2013

    Publisher: The Biophysical Society of Japan General Incorporated Association

    DOI： 10.2142/biophys.53.S195_1 　

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Research Projects 1

  1. 混み合い高分子を流動化させる細胞内部駆動力の解明

    西澤 賢治

    Offer Organization: 日本学術振興会

    System: 科学研究費助成事業

    Category: 若手研究

    Institution: 東京大学

    2024/04/01 - 2029/03/31