Researcher Information

Masayuki Takahashi

Associate Professor

Exploring the molecular mechanism of controlling cell shape

Department of Chemistry, Organic and Biological Chemistry

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Theme

Studies of the molecular mechanism of change and maintenance of cell shape through intracellular contractile apparatus

FieldBiochemistry, Cell biology, Molecular biology
KeywordProtein, Myosin II, Actin, Cell motility, Cytoskeleton, Cell migration, Cytokinesis

Introduction of Research

Myosin was discovered as a protein responsible for skeletal muscle contraction and since then has been the subject of extensive research. Myosin utilizes the energy generated from ATP hydrolysis to translocate actin filaments. Most of the cells in our body contain nonmuscle myosin II, which plays an important role in cellular motile processes such as cytokinesis and migration. Similar to myosin in muscles, myosin II, can function only when assembled as filaments. In contrast to muscle myosin that forms filaments all the time, myosin II assembles and forms filaments only when necessary. Myosin II can change the morphology of cells by translocating the actin filaments anchored to the membrane (Fig. 1). Cell motility can thus be perceived as localized changes in cellular morphology. Furthermore, maintaining the altered morphology of cells is an important function of myosin II and actin, so that the cell can function normally. Myosin II occurs as three isoforms in mammals; however, the functional differences among these isoforms are still unclear (Fig. 2). Our research aims to elucidate the function of these isoforms to better understand the underlying mechanism behind changes in and maintenance of cellular morphology. We are using methods in cell biology that incorporate some recent advances in technology and aiming towards research that can be called “protein chemistry using the cell as a test tube.”

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Fig. 1. Intracellular contractile apparatuses
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Fig. 2. Localization of myosin IIA and myosin IIB in a migrating normal fibroblast cell

Representative Achievements

Different contributions of nonmuscle myosin IIA and IIB to the organization of stress fiber subtypes in fibroblasts, M. Kuragano, T. Q. P. Uyeda, K. Kamijo, Y. Murakami and M. Takahashi, Mol. Biol. Cell, 2018, 29, 911-922.
Nonmuscle myosin IIA and IIB differentially contribute to intrinsic and directed migration of human embryonic lung fibroblasts, M. Kuragano, Y. Murakami and M. Takahashi, Biochem. Biophys. Res. Commun., 2018, 498, 25-31.
Nonmuscle myosin II folds into a 10S form via two portions of tail for dynamic subcellular localization, T. Kiboku, T. Katoh, A. Nakamura, A. Kitamura, M. Kinjo, Y. Murakami and M. Takahashi, Genes Cells, 2013, 18, 90-109.
Critical regions for assembly of vertebrate nonmuscle myosin II, T. Nakasawa, M. Takahashi, F. Matsuzawa, S. Aikawa, Y. Togashi, T. Saitoh, A. Yamagishi and M. Yazawa, Biochemistry, 2005, 44, 174-183.
Differential localization of nonmuscle myosin II isoforms and phosphorylated regulatory light chains in human MRC-5 fibroblasts, T. Saitoh, S. Takemura, K. Ueda, H. Hosoya, M.Nagayama, H. Haga, K. Kawabata, A. Yamagishi and M. Takahashi, FEBS Lett., 2001, 509, 365-369. (Cover picture)
Academic degreePh.D.
Academic background1983 B.Sc. Department of Chemistry II, School of Science, Hokkaido University
1985 M.Sc. Graduate School of Science, Hokkaido University
1988 Completed Ph.D. program without a Ph.D. degree, Graduate School of Science, Hokkaido University
1989 Ph.D. Graduate School of Science, Hokkaido University
1988-1989 Kao Corporation
1989-1992 Postdoctoral fellow, NHLBI, NIH, USA
1992-1993 Assistant Professor, Department of Polymer Science, School of Science, Hokkaido University
1993-2001 Assistant Professor, Department of Biological Sciences, Graduate School of Science, Hokkaido University
2001-2007 Associate Professor, Division of Chemistry, Graduate School of Science, Hokkaido University
2007-present Associate Professor, Graduate School of Chemical Sciences and Engineering, Hokkaido University
Affiliated academic societyThe Japanese Biochemical Society, Japan Society for Cell Biology, The Molecular Biology Society of Japan, The Chemical Society of Japan, The American Society for Cell Biology
Room addressGeneral Research Building 2 2-202