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Yusuke T MAEDA Last modified date:2023.08.29

Associate Professor / Condensed matter physics
Department of Physics
Faculty of Sciences

Graduate School
Undergraduate School

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Academic Degree
Ph.D in Physics
Country of degree conferring institution (Overseas)
Field of Specialization
Non-equilibrium statistical physics, Active matter physics, Synthetic biology
Total Priod of education and research career in the foreign country
Outline Activities
We study the physics of dynamic and complex systems involved in biological phenomena.
Research Interests
  • Self-reproduction is unique property for living systems that distinct from non-living matters. We study the design principles of self-reproducing artificial cells by constructive approach.
    keyword : Artificial cells, Synthetic biology, Nonlinear systems
  • To understand the principles of dynamic and complex systems involved in biological phenomena, our lab studies
    1. Transport phenomena and fluid dynamics far from equilibrium
    2. Physics of active matters
    keyword : Non-equilibrium physics, Nonlinear dynamics, Active matters
Academic Activities
1. Sakamoto R, Miyazaki M, and Maeda YT, State transitions of a confined actomyosin system controlled through contractility and polymerization rate, Physical Review Research, 5, 013208, 2023.03.
2. Fukuyama T, Yan LC, Tanaka M, Yamaoka M, Saito K, Ti SC, Liao CC, Hsia KC, Maeda YT and Shimamoto Y, Morphological growth dynamics, mechanical stability, and active microtubule mechanics underlying spindle self-organization, Proceedings of the National Academy of Sciences of USA, 119, 44, e2209053119, 2022.10, The spindle is a dynamic intracellular structure self-organized from microtubules and microtubule-associated proteins. The spindle’s bipolar morphology is essential for the faithful segregation of chromosomes during cell division, and it is robustly maintained by multifaceted mechanisms. However, abnormally shaped spindles, such as multipolar spindles, can stochastically arise in a cell population and cause chromosome segregation errors. The physical basis of how microtubules fail in bipolarization and occasionally favor nonbipolar assembly is poorly understood. Here, using live fluorescence imaging and quantitative shape analysis in Xenopus egg extracts, we find that spindles of varied shape morphologies emerge through nonrandom, bistable self-organization paths, one leading to a bipolar and the other leading to a multipolar phenotype. The bistability defines the spindle’s unique morphological growth dynamics linked to each shape phenotype and can be promoted by a locally distorted microtubule flow that arises within premature structures. We also find that bipolar and multipolar spindles are stable at the steady-state in bulk but can infrequently switch between the two phenotypes. Our microneedle-based physical manipulation further demonstrates that a transient force perturbation applied near the assembled pole can trigger the phenotypic switching, revealing the mechanical plasticity of the spindle. Together with molecular perturbation of kinesin-5 and augmin, our data propose the physical and molecular bases underlying the emergence of spindle-shape variation, which influences chromosome segregation fidelity during cell division..
3. Sakamoto R, Izri Z, Shimamoto Y, Miyazaki M, and Maeda YT, Geometric trade-off between contractile force and viscous drag determines the actomyosin-based motility of a cell-sized droplet, Proceedings of the National Academy of Sciences of USA, 119, 30, e2121147119, 2022.07, Cell migration in confined environments is fundamental for diverse biological processes from cancer invasion to leukocyte trafficking. The cell body is propelled by the contractile force of actomyosin networks transmitted from the cell membrane to the external substrates. However, physical determinants of actomyosin-based migration capacity in confined environments are not fully understood. Here, we develop an in vitro migratory cell model, where cytoplasmic actomyosin networks are encapsulated into droplets surrounded by a lipid monolayer membrane. We find that the droplet can move when the actomyosin networks are bound to the membrane, in which the physical interaction between the contracting actomyosin networks and the membrane generates a propulsive force. The droplet moves faster when it has a larger contact area with the substrates, while narrower confinement reduces the migration speed. By combining experimental observations and active gel theory, we propose a mechanism where the balance between sliding friction force, which is a reaction force of the contractile force, and viscous drag determines the migration speed, providing a physical basis of actomyosin-based motility in confined environments..
4. Araki S, Beppu K, Kabir AMR, Kakugo A, and Maeda YT, Controlling collective motion of kinesin-driven microtubules via patterning of topographic landscapes, Nano Letters, 21, 24, 10478-10485, 2021.12, Biomolecular motor proteins that generate forces by consuming chemical energy obtained from ATP hydrolysis play pivotal roles in organizing cytoskeletal structures in living cells. An ability to control cytoskeletal structures would benefit programmable protein patterning; however, our current knowledge is limited because of the underdevelopment of engineering approaches for controlling pattern formation. Here, we demonstrate the controlling of self-assembled patterns of microtubules (MTs) driven by kinesin motors by designing the boundary shape in fabricated microwells. By manipulating the collision angle of gliding MTs defined by the boundary shape, the self-assembly of MTs can be controlled to form protruding bundle and bridge patterns. Corroborated by the theory of self-propelled rods, we further show that the alignment of MTs determines the transition between the assembled patterns, providing a blueprint to reconstruct bridge structures in microchannels. Our findings introduce the tailoring of the self-organization of cytoskeletons and motor proteins for nanotechnological applications..
5. Beppu K, Izri Z, Sato T, Yamanishi Y, Sumino Y, and Maeda YT, Edge current and pairing order transition in chiral bacterial vortices, Proceedings of the National Academy of Sciences of USA, 118, 39, e2107461118, 2021.09, Bacterial suspensions show turbulence-like spatiotemporal dynamics and vortices moving irregularly inside the suspensions. Understanding these ordered vortices is an ongoing challenge in active matter physics, and their application to the control of autonomous material transport will provide significant development in microfluidics. Despite the extensive studies, one of the key aspects of bacterial propulsion has remained elusive: The motion of bacteria is chiral, i.e., it breaks mirror symmetry. Therefore, the mechanism of control of macroscopic active turbulence by microscopic chirality is still poorly understood. Here, we report the selective stabilization of chiral rotational direction of bacterial vortices in achiral circular microwells sealed by an oil/water interface. The intrinsic chirality of bacterial swimming near the top and bottom interfaces generates chiral collective motions of bacteria at the lateral boundary of the microwell that are opposite in directions. These edge currents grow stronger as bacterial density increases, and, within different top and bottom interfaces, their competition leads to a global rotation of the bacterial suspension in a favored direction, breaking the mirror symmetry of the system. We further demonstrate that chiral edge current favors corotational configurations of interacting vortices, enhancing their ordering. The intrinsic chirality of bacteria is a key feature of the pairing order transition from active turbulence, and the geometric rule of pairing order transition may shed light on the strategy for designing chiral active matter..
6. Sakamoto R, Tanabe M, Hiraiwa T, Suzuki K, Ishiwata S-i, Maeda YT, and Miyazaki M, Tug-of-war between actomyosin-driven antagonistic forces determines the positioning symmetry in cell-sized confinement, Nature Communications, 11, 3063, 2020.06.
7. Jun Takagi, Ryota Sakamoto, Gen Shirotsuchi, Yusuke T. Maeda, Yuta Shimamoto, Mechanically distinct microtubule arrays determine the length and force response of the meiotic spindle, Developmental Cell, 49, 2, 267-278, 2019.04, [URL].
8. Tatsuya Fukuyama, Sho Nakama, Yusuke T. Maeda, Thermal molecular focusing: Tunable cross effect of phoresis and light-driven hydrodynamic focusing, Soft Matter, 14, 5519-5524, 2018.06, [URL].
9. Kazusa Beppu, Ziane Izri, Jun Gohya, Kanta Eto, Masatoshi Ichikawa, Yusuke T. Maeda, Geometry-driven collective ordering of bacterial vortices, Soft Matter, 13, 5038-5043, 2017.07, [URL].
10. Yusuke T. MAEDA, Tsvi Tlusty, Albert Libchaber, Effects of Long DNA Folding and Small RNA Stem-loop in Thermophoresis, Proceedings of the National Academy of Sciences of USA, 109, 17972-17977, 2012.10, [URL].
11. Vincent Noireaux, Yusuke T. MAEDA, Albert Libchaber, Development of an Artificial Cell, from Self-organization to Computation and Self-reproduction, Proceedings of the National Academy of Sciences of USA, 108, 3473-3480, 2011.02, [URL].
12. Yusuke T. MAEDA, Axel Buguin, Albert Libchaber, Thermal separation: Interplay between the soret effect and entropic force gradient, Physical Review Letters, 107, 3, 038301, 2011.07.
13. Yuta Shimamoto, Yusuke T. MAEDA, Shin'ichi Ishiwata, Albert J. Libchaber, Tarun M. Kapoor, Insights into the micromechanical properties of the metaphase spindle, Cell, 145, 1062-1074, 2011.06.
1. 前多 裕介, 動的な温度勾配・濃度勾配下の周波数特異的な輸送現象, 日本物理学会第70回年次大会, 2015.03.
Membership in Academic Society
  • The Biophysical Society of Japan
  • The American Physical Society
  • The Physical Society of Japan