論文 - 鈴木　量

Extracellular calcium functions as a molecular glue for transmembrane helices to activate the scramblase Xkr4

Zhang, Panpan, Maruoka, Masahiro, Suzuki, Ryo, Katani, Hikaru, Dou, Yu, Packwood, Daniel M., Kosako, Hidetaka, Tanaka, Motomu and Suzuki, Jun

Nature Communications 14 （ 1 ） 5592 2023年

ISSN  2041-1723

　概要を見る

The “eat me” signal, phosphatidylserine is exposed on the surface of dying cells by phospholipid scrambling. Previously, we showed that the Xkr family protein Xkr4 is activated by caspase-mediated cleavage and binding of the XRCC4 fragment. Here, we show that extracellular calcium is an additional factor needed to activate Xkr4. The constitutively active mutant of Xkr4 is found to induce phospholipid scrambling in an extracellular, but not intracellular, calcium-dependent manner. Importantly, other Xkr family members also require extracellular calcium for activation. Alanine scanning shows that D123 and D127 of TM1 and E310 of TM3 coordinate calcium binding. Moreover, lysine scanning demonstrates that the E310K mutation-mediated salt bridge between TM1 and TM3 bypasses the requirement of calcium. Cysteine scanning proves that disulfide bond formation between TM1 and TM3 also activates phospholipid scrambling without calcium. Collectively, this study shows that extracellular calcium functions as a molecular glue for TM1 and TM3 of Xkr proteins for activation, thus demonstrating a regulatory mechanism for multi-transmembrane region-containing proteins.

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Wnt/β-catenin signaling induces axial elasticity patterns of Hydra extracellular matrix

Veschgini, Mariam, Suzuki, Ryo, Kling, Svenja, Petersen, Hendrik O., Bergheim, Bruno Gideon, Abuillan, Wasim, Linke, Philipp, Kaufmann, Stefan, Burghammer, Manfred, Engel, Ulrike, Stein, Frank, Özbek, Suat, Holstein, Thomas W. and Tanaka, Motomu

iScience 26 （ 4 ）  2023年

ISSN  2589-0042

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Spatio-temporal Coordination of Active Deformation Forces and Wnt/Hippo-Yap Signaling in Hydra Regeneration

Suzuki, Ryo, Hiraiwa, Tetsuya, Tursch, Anja, Höger, Stefanie, Hayashi, Kentaro, Özbek, Suat, Holstein, Thomas W and Tanaka, Motomu

BioRXiv    2023.09. 18.558226 2023年

Ion-specific nanoscale compaction of cysteine-modified poly (acrylic acid) brushes revealed by 3D scanning force microscopy with frequency modulation detection

Yamamoto, Akihisa, Ikarashi, Takahiko, Fukuma, Takeshi, Suzuki, Ryo, Nakahata, Masaki, Miyata, Kazuki and Tanaka, Motomu

Nanoscale Advances 4 （ 23 ） 5027 - 5036 2022年

Extreme deformability of insect cell membranes is governed by phospholipid scrambling

Shiomi, Akifumi, Nagao, Kohjiro, Yokota, Nobuhiro, Tsuchiya, Masaki, Kato, Utako, Juni, Naoto, Hara, Yuji, Mori, Masayuki X., Mori, Yasuo, Ui-Tei, Kumiko, Murate, Motohide, Kobayashi, Toshihide, Nishino, Yuri, Miyazawa, Atsuo, Yamamoto, Akihisa, Suzuki, Ryo, Kaufmann, Stefan, Tanaka, Motomu, Tatsumi, Kazuya, Nakabe, Kazuyoshi, Shintaku, Hirofumi, Yesylevsky, Semen, Bogdanov, Mikhail and Umeda, Masato

Cell Reports 35 （ 10 ） 109219 2021年

ISSN  2211-1247

　概要を見る

Summary Organization of dynamic cellular structure is crucial for a variety of cellular functions. In this study, we report that Drosophila and Aedes have highly elastic cell membranes with extremely low membrane tension and high resistance to mechanical stress. In contrast to other eukaryotic cells, phospholipids are symmetrically distributed between the bilayer leaflets of the insect plasma membrane, where phospholipid scramblase (XKR) that disrupts the lipid asymmetry is constitutively active. We also demonstrate that XKR-facilitated phospholipid scrambling promotes the deformability of cell membranes by regulating both actin cortex dynamics and mechanical properties of the phospholipid bilayer. Moreover, XKR-mediated construction of elastic cell membranes is essential for hemocyte circulation in the Drosophila cardiovascular system. Deformation of mammalian cells is also enhanced by the expression of Aedes XKR, and thus phospholipid scrambling may contribute to formation of highly deformable cell membranes in a variety of living eukaryotic cells.

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Force generation by a propagating wave of supramolecular nanofibers

Kubota, Ryou, Makuta, Masahiro, Suzuki, Ryo, Ichikawa, Masatoshi, Tanaka, Motomu and Hamachi, Itaru

Nature Communications 11 （ 1 ） 3541 2020年

ISSN  2041-1723

　概要を見る

Dynamic spatiotemporal patterns that arise from out-of-equilibrium biochemical reactions generate forces in living cells. Despite considerable recent efforts, rational design of spatiotemporal patterns in artificial molecular systems remains at an early stage of development. Here, we describe force generation by a propagating wave of supramolecular nanofibers. Inspired by actin dynamics, a reaction network is designed to control the formation and degradation of nanofibers by two chemically orthogonal stimuli. Real-time fluorescent imaging successfully visualizes the propagating wave based on spatiotemporally coupled generation and collapse of nanofibers. Numerical simulation indicates that the concentration gradient of degradation stimulus and the smaller diffusion coefficient of the nanofiber are critical for wave emergence. Moreover, the force (0.005 pN) generated by chemophoresis and/or depletion force of this propagating wave can move nanobeads along the wave direction.

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Cell surface flip-flop of phosphatidylserine is critical for PIEZO1-mediated myotube formation

Tsuchiya, Masaki, Hara, Yuji, Okuda, Masaki, Itoh, Karin, Nishioka, Ryotaro, Shiomi, Akifumi, Nagao, Kohjiro, Mori, Masayuki, Mori, Yasuo, Ikenouchi, Junichi, Suzuki, Ryo, Tanaka, Motomu, Ohwada, Tomohiko, Aoki, Junken, Kanagawa, Motoi, Toda, Tatsushi, Nagata, Yosuke, Matsuda, Ryoichi, Takayama, Yasunori, Tominaga, Makoto and Umeda, Masato

Nature Communications 9 （ 1 ） 2049 2018年

ISSN  2041-1723

　概要を見る

Myotube formation by fusion of myoblasts and subsequent elongation of the syncytia is essential for skeletal muscle formation. However, molecules that regulate myotube formation remain elusive. Here we identify PIEZO1, a mechanosensitive Ca2+ channel, as a key regulator of myotube formation. During myotube formation, phosphatidylserine, a phospholipid that resides in the inner leaflet of the plasma membrane, is transiently exposed to cell surface and promotes myoblast fusion. We show that cell surface phosphatidylserine inhibits PIEZO1 and that the inward translocation of phosphatidylserine, which is driven by the phospholipid flippase complex of ATP11A and CDC50A, is required for PIEZO1 activation. PIEZO1-mediated Ca2+ influx promotes RhoA/ROCK-mediated actomyosin assemblies at the lateral cortex of myotubes, thus preventing uncontrolled fusion of myotubes and leading to polarized elongation during myotube formation. These results suggest that cell surface flip-flop of phosphatidylserine acts as a molecular switch for PIEZO1 activation that governs proper morphogenesis during myotube formation.

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Emergence of coexisting ordered states in active matter systems

Huber, L., Suzuki, R., Krüger, T., Frey, E. and Bausch, A. R.

Science 361 （ 6399 ） 255 2018年

　概要を見る

In active matter systems, the infusion of energy and motion drives ordering processes. Huber et al. present a combination of experiments and numerical simulations on an active matter system consisting of actin filaments propelled across a surface by surface-attached myosin motor proteins. Adding a depletion agent—polymer chains that weakened interactions between the actin filaments—drove the system between ferromagnetic (polar) and nematic (liquid crystal) ordering.Science, this issue p. 255Active systems can produce a far greater variety of ordered patterns than conventional equilibrium systems. In particular, transitions between disorder and either polar- or nematically ordered phases have been predicted and observed in two-dimensional active systems. However, coexistence between phases of different types of order has not been reported. We demonstrate the emergence of dynamic coexistence of ordered states with fluctuating nematic and polar symmetry in an actomyosin motility assay. Combining experiments with agent-based simulations, we identify sufficiently weak interactions that lack a clear alignment symmetry as a prerequisite for coexistence. Thus, the symmetry of macroscopic order becomes an emergent and dynamic property of the active system. These results provide a pathway by which living systems can express different types of order by using identical building blocks.

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Dynamic Contact Guidance of Myoblasts by Feature Size and Reversible Switching of Substrate Topography: Orchestration of Cell Shape, Orientation, and Nematic Ordering of Actin Cytoskeletons

Linke, Philipp, Suzuki, Ryo, Yamamoto, Akihisa, Nakahata, Masaki, Kengaku, Mineko, Fujiwara, Takahiro, Ohzono, Takuya and Tanaka, Motomu

Langmuir 2018年

ISSN  0743-7463

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The emergence and transient behaviour of collective motion in active filament systems

Suzuki, Ryo and Bausch, Andreas R.

Nature Communications 8 （ 1 ） 41 2017年

ISSN  2041-1723

　概要を見る

Most living systems, ranging from animal flocks, self-motile microorganisms to the cytoskeleton rely on self-organization processes to perform their own specific function. Despite its importance, the general understanding of how individual active constituents initiate the intriguing pattern formation phenomena on all these different length scales still remains elusive. Here, using a high density actomyosin motility assay system, we show that the observed collective motion arises from a seeding process driven by enhanced acute angle collisions. Once a critical size is reached, the clusters coarsen into high and low density phases each with fixed filament concentrations. The steady state is defined by a balance of collision induced randomization and alignment effects of the filaments by multi-filament collisions within ordered clusters.

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Tracking mechanical and morphological dynamics of regenerating Hydra tissue fragments using a two fingered micro-robotic hand

Veschgini, M., Gebert, F., Khangai, N., Ito, H., Suzuki, R., Holstein, T. W., Mae, Y., Arai, T. and Tanaka, M.

Applied Physics Letters 108 （ 10 ） 103702 2016年

ISSN  0003-6951

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Polar pattern formation in driven filament systems requires non-binary particle collisions

Suzuki, Ryo, Weber, Christoph A., Frey, Erwin and Bausch, Andreas R.

Nature Physics 11   839 2015年

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Random bursts determine dynamics of active filaments

Weber, Christoph A., Suzuki, Ryo, Schaller, Volker, Aranson, Igor S., Bausch, Andreas R. and Frey, Erwin

Proceedings of the National Academy of Sciences 112 （ 34 ） 10703 2015年

　概要を見る

Biological active systems like swimming bacteria or molecular motors in the cell cytoskeleton consume energy locally to create movements or stresses. Although the surrounding fluid gives rise to thermal fluctuations of the system’s dynamic variables, the corresponding statistics can deviate significantly from a thermal Boltzmann distribution. To quantify these differences, we compare the statistics and dynamics of actin filaments driven by molecular motors with Brownian filaments. In both cases, energy injection is local and random; however, for active filaments, motors can generate sudden jump-like changes in the system’s dynamic variables, leading to nonequilibrium energy dissipation. Motor activity results in a nonthermal distribution of filament curvatures and a faster relaxation of filament bends than in the thermal case.Constituents of living or synthetic active matter have access to a local energy supply that serves to keep the system out of thermal equilibrium. The statistical properties of such fluctuating active systems differ from those of their equilibrium counterparts. Using the actin filament gliding assay as a model, we studied how nonthermal distributions emerge in active matter. We found that the basic mechanism involves the interplay between local and random injection of energy, acting as an analog of a thermal heat bath, and nonequilibrium energy dissipation processes associated with sudden jump-like changes in the system’s dynamic variables. We show here how such a mechanism leads to a nonthermal distribution of filament curvatures with a non-Gaussian shape. The experimental curvature statistics and filament relaxation dynamics are reproduced quantitatively by stochastic computer simulations and a simple kinetic model.

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Validity of fluctuation theorem on self-propelling particles

Suzuki, Ryo, Jiang, Hong-Ren and Sano, Masaki

arXiv preprint arXiv:1104.5607 2011年

ジェルのダンス : 加振による複雑流体の対流現象(小特集：みぢかなモノの「ウゴキ」・「カタチ」)

佐野, 雅己, 鈴木, 量 and 村山, 能宏

日本物理学会誌 64 （ 10 ） 767 - 772 2009年

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