Osawa Masatake

J-GLOBAL         Last updated: Jul 2, 2019 at 02:42
Osawa Masatake
Gifu University
Graduate School of Medicine
Job title


My ultimate research goal is to clarify molecular and cellular mechanisms underlying in the regulation of stem cells. To this end, as a model system to study stem cell biology, we have been investigating melanocyte stem cells (MSCs) that we have previously identified in the mouse hair follicle (Nature 2002). Stem cells play crucial roles in the maintenance of proper tissue homeostasis. Elucidation of molecular mechanisms underlying stem cell regulation is of great importance both for developmental biology and for clinical applications in regenerative medicine and cancer therapy. It is a widely accepted that stem cells are regulated by their specialized microenvironment, termed stem cell niches. However, because of difficulties of identifying the niches in situ, the exact mechanisms underlying stem cell regulation by the niche have remained largely unknown.
We have established a method to isolate highly purified hematopoietic stem cells (HSCs) from murine bone marrow (Science 1996). In this work, by transplanting single stem cells into lethally irradiated host, we demonstrated experimental proof for the concept of the HSC; a single cell that can reconstitute the entire blood and lymphoid system. Using the purified HSCs, we have performed gene expression profiling analysis and defined molecular signature of HSCs. Using this information, we have determined a indispensable role of Necdin in the regulation of HSC self-renewal (Blood, 2009)
For the last 5 years or so, my research group is working on MSCs. Melanocytes provide an attractive system to study the molecular basis of cell regulation, since genetic alterations involved in melanocyte regulations are easily identifiable as coat color mutants. Taking this advantage, we are trying to define molecular mechanisms involved in the regulation of MSCs. By performing a single-cell based gene expression analysis of MSCs (Development, 2005), we have identified genes preferentially expressed in MSCs. Among these genes, we have demonstrated the indispensable role of Notch signaling in the maintenance of MSCs (J Cell Biol, 2006). We are currently using this information to investigate how the cross-talk of these signals is implicated in the regulation of MSCs. Along with this line, by establishing in vivo assay system to explore gene functions in MSC regulation (J Invest Dermatol, 2008), we continue and extend our functional analysis to uncover key molecular pathways that govern MSC regulation.
We have recently extended our interest on the epidermal stem cell system. By isolating various different subsets of cell populations of the epidermis, we have determined gene expression profiles of epidermal keratinocytes and dermal papilla cells. These data have led us to define the functions of Ephrin and Notch signaling pathways in the homeostatic regulation of epidermal keratinocytes (J Invest Dermatol, 2009, Dev Cell, 2008).
By integrating these data, I hope to provide new insights into our understanding of the nature of stem cell regulation at the molecular and cellular levels and to bring a new paradigm in explaining how dysfunction of normal homeostatic regulation of stem cell system results in cancerous transformation. These studies would provide new therapeutic strategies in cancer treatment.

Research Areas


Published Papers

Islam S, Ueda M, Nishida E, Wang MX, Osawa M, Lee D, Itoh M, Nakagawa K, Tana, Nakagawa T
Brain research   1688 81-90   Jun 2018   [Refereed]
Kakuda K, Niwa A, Honda R, Yamaguchi KI, Tomita H, Nojebuzzaman M, Hara A, Goto Y, Osawa M, Kuwata K
Journal of biochemistry   165(4) 369-378   Apr 2019   [Refereed]
Nagashima K, Miwa T, Soumiya H, Ushiro D, Takeda-Kawaguchi T, Tamaoki N, Ishiguro S, Sato Y, Miyamoto K, Ohno T, Osawa M, Kunisada T, Shibata T, Tezuka KI, Furukawa S, Fukumitsu H
Scientific reports   7(1) 13500   Oct 2017   [Refereed]
Nishikawa-Torikai S, Osawa M, Nishikawa SI
J Invest Dermatol   131(12) 2358-2367   Dec 2011   [Refereed]
Real-Time RT-PCR Analysis of Individual Osteolineage Cells within the Hematopoietic Stem Cell Niche
Silberstein Lev, Osawa Masatake, Lin Charles, Kharchenko Peter, Lo Celso Cristina, Aribeana Chiaka, Scadden David T.
BLOOD   118(21) 1028-1029   Nov 2011   [Refereed]
Aoki H, Hara A, Motohashi T, OsawaM, Kunisada T
Pigment Cell and Melanoma Research   24(1) 125-135   Feb 2011   [Refereed]
Silberstein L, Goncalves KA, Kharchenko PV, Turcotte R, Kfoury Y, Mercier F, Baryawno N, Severe N, Bachand J, Spencer JA, Papazian A, Lee D, Chitteti BR, Srour EF, Hoggatt J, Tate T, Lo Celso C, Ono N, Nutt S, Heino J, Sipilä K, Shioda T, Osawa M, Lin CP, Hu GF, Scadden DT
Cell stem cell   19(4) 530-543   Oct 2016   [Refereed]
Freter R, Osawa M, Nishikawa S
Stem cells (Dayton, Ohio)   28(9) 1571-1580   Sep 2010   [Refereed]
Moriyama M, Moriyama H, Uda J, Matsuyama A, Osawa M, Hayakawa T
The Journal of investigative dermatology   134(6) 1627-1635   Jun 2014   [Refereed]
Kubota Y, Osawa M, Jakt LM, Yoshikawa K, Nishikawa S
Blood   114(20) 4383-4392   Nov 2009   [Refereed]
Egawa G, Osawa M, Uemura A, Miyachi Y, Nishikawa S
The Journal of investigative dermatology   129(10) 2386-2395   Oct 2009   [Refereed]
Osawa M, Fisher DE
The Journal of investigative dermatology   128(11) 2571-2574   Nov 2008   [Refereed]
Inoue-Narita T, Hamada K, Sasaki T, Hatakeyama S, Fujita S, Kawahara K, Sasaki M, Kishimoto H, Eguchi S, Kojima I, Beermann F, Kimura T, Osawa M, Itami S, Mak TW, Nakano T, Manabe M, Suzuki A
Cancer research   68(14) 5760-5768   Jul 2008   [Refereed]
Melanocyte stem cells: as a model to study stem cell biology
Osawa Masatake
PIGMENT CELL & MELANOMA RESEARCH   21(2) 294   Apr 2008   [Refereed]
Control of melanocyte diversification
Nishikawa-Torikai Satomi, Yonetani Saori, Freter Rasmus, Osawa Masatake, Nishikawa Shin-Ichi
PIGMENT CELL & MELANOMA RESEARCH   21(2) 308   Apr 2008   [Refereed]
Yonetani S, Moriyama M, Nishigori C, Osawa M, Nishikawa S
The Journal of investigative dermatology   128(2) 408-420   Feb 2008   [Refereed]
Moriyama M, Durham AD, Moriyama H, Hasegawa K, Nishikawa S, Radtke F, Osawa M
Developmental cell   14(4) 594-604   Apr 2008   [Refereed]
Nishikawa S, Osawa M
Pigment cell research   20(4) 263-270   Aug 2007   [Refereed]
Osawa M
   2008   [Refereed]
Moriyama M, Osawa M, Mak SS, Ohtsuka T, Yamamoto N, Han H, Delmas V, Kageyama R, Beermann F, Larue L, Nishikawa S
The Journal of cell biology   173(3) 333-339   May 2006   [Refereed]
Mak SS, Moriyama M, Nishioka E, Osawa M, Nishikawa S
Developmental biology   291(1) 144-153   Mar 2006   [Refereed]
What is a stem cell niche?
Nishikawa SI, Osawa M
Ernst Schering Research Foundation workshop   (60) 1-14   2006   [Refereed]
Osawa M, Egawa G, Mak SS, Moriyama M, Freter R, Yonetani S, Beermann F, Nishikawa S
Development (Cambridge, England)   132(24) 5589-5599   Dec 2005   [Refereed]
Melanocyte system for studying stem cell niche.
Nishikawa SI, Osawa M
Ernst Schering Research Foundation workshop   (54) 1-13   2005   [Refereed]
[Stem cells in the mammalian hair follicle].
Osawa M, Nishimura EK
Tanpakushitsu kakusan koso. Protein, nucleic acid, enzyme   49(6) 727-733   May 2004   [Refereed]
Hirobe T, Osawa M, Nishikawa S
Pigment cell research   17(1) 51-61   Feb 2004   [Refereed]
Hirobe T, Osawa M, Nishikawa S
Pigment cell research   16(6) 644-655   Dec 2003   [Refereed]
Kunisato A, Chiba S, Nakagami-Yamaguchi E, Kumano K, Saito T, Masuda S, Yamaguchi T, Osawa M, Kageyama R, Nakauchi H, Nishikawa M, Hirai H
Blood   101(5) 1777-1783   Mar 2003   [Refereed]
Kirito K, Osawa M, Morita H, Shimizu R, Yamamoto M, Oda A, Fujita H, Tanaka M, Nakajima K, Miura Y, Ozawa K, Komatsu N
Blood   99(9) 3220-3227   May 2002   [Refereed]
Nishimura EK, Jordan SA, Oshima H, Yoshida H, Osawa M, Moriyama M, Jackson IJ, Barrandon Y, Miyachi Y, Nishikawa S
Nature   416(6883) 854-860   Apr 2002   [Refereed]
Yoneya T, Tahara T, Nagao K, Yamada Y, Yamamoto T, Osawa M, Miyatani S, Nishikawa M
Journal of biochemistry   129(1) 27-34   Jan 2001   [Refereed]
Masuhara M, Nagao K, Nishikawa M, Sasaki M, Yoshimura A, Osawa M
Biochemical and biophysical research communications   268(3) 697-703   Feb 2000   [Refereed]
A role for pref-1 and HES-1 in thymocyte development.
Kaneta M, Osawa M, Sudo K, Nakauchi H, Farr AG, Takahama Y
Journal of immunology (Baltimore, Md. : 1950)   164(1) 256-264   Jan 2000   [Refereed]
Nakauchi H, Takano H, Ema H, Osawa M
Annals of the New York Academy of Sciences   872 57-66; discussion 66   Apr 1999   [Refereed]
alpha-Galactosylceramide (AGL-517) treatment protects mice from lethal irradiation.
Inoue H, Koezuka Y, Nishi N, Osawa M, Motoki K, Kobayashi E, Kabaya K, Obuchi M, Fukushima H, Mori KJ
Experimental hematology   25(9) 935-944   Aug 1997   [Refereed]
Usuki K, Tahara T, Iki S, Endo M, Osawa M, Kitazume K, Kato T, Miyazaki H, Urabe A
Stem cells (Dayton, Ohio)   14(5) 558-565   Sep 1996   [Refereed]
Osawa M, Hanada K, Hamada H, Nakauchi H
Science (New York, N.Y.)   273(5272) 242-245   Jul 1996   [Refereed]
In vivo self-renewal of c-Kit+ Sca-1+ Lin(low/-) hemopoietic stem cells.
Osawa M, Nakamura K, Nishi N, Takahasi N, Tokuomoto Y, Inoue H, Nakauchi H
Journal of immunology (Baltimore, Md. : 1950)   156(9) 3207-3214   May 1996   [Refereed]
Developmental defects of lymphoid cells in Jak3 kinase-deficient mice.
Park SY, Saijo K, Takahashi T, Osawa M, Arase H, Hirayama N, Miyake K, Nakauchi H, Shirasawa T, Saito T
Immunity   3(6) 771-782   Dec 1995   [Refereed]
Nishi N, Osawa M, Ishikawa R, Nishikawa M, Tsumura H, Inoue H, Sudo T
Stem cells (Dayton, Ohio)   13(5) 517-523   Sep 1995   [Refereed]
A highly enhanced thrombopoietic activity by monomethoxy polyethylene glycol-modified recombinant human interleukin-6.
Inoue H, Kadoya T, Kabaya K, Tachibana K, Nishi N, Sato M, Ohsawa M, Mikayama T, Mori KJ
The Journal of laboratory and clinical medicine   124(4) 529-536   Oct 1994   [Refereed]
Beta-actinin is equivalent to Cap Z protein.
Maruyama K, Kurokawa H, Oosawa M, Shimaoka S, Yamamoto H, Ito M, Maruyama K
The Journal of biological chemistry   265(15) 8712-8715   May 1990   [Refereed]
Physarum myosin light chain interacts with actin in a Ca2+-dependent manner.
Kohama K, Oosawa M, Ito T, Maruyama K
Journal of biochemistry   104(6) 995-998   Dec 1988   [Refereed]
Beta-actinin is not distinguishable from an actin barbed-end capping protein in chicken breast muscle.
Oosawa M, Shimaoka S, Funatsu T, Ishiwata S, Maruyama K
Journal of biochemistry   101(6) 1481-1483   Jun 1987   [Refereed]
Oosawa M, Maruyama K
FEBS letters   213(2) 433-437   Mar 1987   [Refereed]
Effects of chaetoglobosin J on the G-F transformation of actin.
Maruyama K, Oosawa M, Tashiro A, Suzuki T, Tanikawa M, Kikuchi M, Sekita S, Natori S
Biochimica et biophysica acta   874(2) 137-143   Nov 1986   [Refereed]
An intermediate state of G-actin between native and denatured: polymerization rate decreases but extent of polymerization remains unchanged.
Oosawa M, Maruyama K
Journal of biochemistry   100(4) 1001-1008   Oct 1986   [Refereed]

Research Grants & Projects

Japan Society for the Promotion of Science: Grants-in-Aid for Scientific Research
Project Year: 2014 - 2015
Ministry of Education, Culture, Sports, Science and Technology: Grants-in-Aid for Scientific Research(基盤研究(C))
Project Year: 2004 - 2005    Investigator(s): Masatake OSAWA
Emerging evidences from stem cell (SC) research have strengthened the idea that SC fate is determined by a specialized environment, known as a SC niche. However, the exact mechanisms underlying SC regulation by the niche remain elusive because of ...
Ministry of Education, Culture, Sports, Science and Technology: Grants-in-Aid for Scientific Research(基盤研究(C))
Project Year: 2002 - 2003    Investigator(s): Masatake OSAWA
Stem cells are defined as cells that have the dual capacity to generate mature cells through differentiation and to maintain themselves through self-renewal. The differentiation and self-renewal of stem cells are tightly controlled by their partic...
Ministry of Education, Culture, Sports, Science and Technology: Grants-in-Aid for Scientific Research(挑戦的萌芽研究)
Project Year: 2012 - 2013    Investigator(s): Masatake OSAWA
The melanocyte affords an advantageous model for studying gene function through phenotype-based analysis, since alterations in genes involved in melanocyte regulation are easily identifiable as pigmentary phenotypes in the mouse. However, despite ...
Japan Society for the Promotion of Science: Grants-in-Aid for Scientific Research
Project Year: 2012 - 2013