Fukuzawa, Toshihiko

写真a

Affiliation

Faculty of Business and Commerce （Hiyoshi）

Position

Professor
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Profile Summary 【 Display / hide 】

  • 生物の大きな特徴は、発生に伴って形や模様が形成されることである。中でも我々になじみ深いのは、生物の体表における色鮮やかな模様である。生物の模様は、色素を含有する特殊な細胞（色素細胞）が、体表で規則的に分布することによって形成される。特に変温脊椎動物では、多様な色素細胞（黒色、虹色、白色、黄色、赤色、青色）が存在する。筆者は、生物における多様な色素細胞の発現機構と、模様形成のしくみを研究している。

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Career 【 Display / hide 】

  • 1987.04
    -
    1991.03

    Research Associate, College of Medicine, University of Arizona

  • 1991.04
    -
    1996.03

    大学助手（商学部）

  • 1996.04
    -
    2007.03

    大学助教授（商学部）

  • 2001.10
    -
    2003.09

    大学商学部学習指導副主任

  • 2003.10
    -
    2005.09

    学部長補佐（商学部）

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Academic Background 【 Display / hide 】

  • 1982.03

    Tohoku University, Faculty of Science, Department of Biology

    University, Graduated

  • 1984.03

    Tohoku University, Graduate School, Division of Natural Science

    Graduate School, Completed, Master's course

  • 1987.03

    Tohoku University, Graduate School of Science, Biology

    Graduate School, Completed, Doctoral course

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Academic Degrees 【 Display / hide 】

  • Ph.D., Tohoku University, Coursework, 1987.03

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Research Areas 【 Display / hide 】

  • Life Science / Cell biology (Cell Biology)

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Research Keywords 【 Display / hide 】

  • pigment pattern

  • pigment cell

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Books 【 Display / hide 】

  • Commentary book of "Animal body color"

    秋山　豊子，持田　浩治，福澤　利彦　他, グラフィック社, 2022.07,  Page： 324ページ

    Scope: 両生類の体色,  Contact page： pp.168-197

  • 生物学

    FUKUZAWA TOSHIHIKO, 2005.04

  • Pigment Cell

    慶応義塾大学出版,日本, 2001.10

    Scope: 第11章　両生類の体表における色素パターン形成,  Contact page： pp.151-160

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Papers 【 Display / hide 】

  • Periodic albinism of a widely used albino mutant of Xenopus laevis caused by deletion of two exons in the Hermansky–Pudlak syndrome type 4 gene

    福澤利彦

    Genes to Cells （Genes to Cells)  26 （ 1 ） 31 - 39 2021

    Research paper (scientific journal), Single Work, Accepted,  ISSN  13569597

    　View Summary

    © 2020 The Authors. Genes to Cells published by Molecular Biology Society of Japan and John Wiley & Sons Australia, Ltd The periodic albino mutant of Xenopus laevis is a recessive mutant, in which reduced amounts of melanin appear in the retinal pigment epithelium (RPE) and in melanophores at the late embryonic stage, after which both RPE and melanophores gradually depigment. Three types of pigment cells (melanophores, iridophores and xanthophores) have been reported to be affected in this albino. However, the causative gene of the periodic albinism remains unknown. Hermansky–Pudlak syndrome (HPS) is an autosomal recessive disorder that affects humans and mice, which is caused by defective biogenesis of lysosome-related organelles (LROs). Two subgenomes (L and S) are present in the allotetraploid frog X. laevis. Comparison of genes between the chromosomes 1L and 1S revealed that the HPS type 4 (hps4) gene was present only in chromosome 1L. In the albino mutant, a 1.9 kb genomic deletion in the hps4.L gene including exons 7 and 8 caused a premature stop codon to create a truncated Hps4 protein. Injection of wild-type hps4.L mRNA into mutant embryos rescued the albino phenotype. These findings indicate that hps4 is a causative gene for the periodic albinism in X. laevis. The phenotype of this mutant should be reassessed from the perspective of LRO biogenesis.

  • Unusual light-reflecting pigment cells appear in the Xenopus neural tube culture system in the presence of guanosine.

    FUKUZAWA TOSHIHIKO

    Tissue and Cell （Tissue and Cell)  54   55 - 58 2018.10

    Research paper (scientific journal), Joint Work, Accepted,  ISSN  00408166

    　View Summary

    © 2018 Elsevier Ltd Isolation and culture of Xenopus laevis neural tubes resulted in differentiation of melanophores and iridophores from neural crest cells; the differentiated melanophores and iridophores were then maintained in culture for more than 6 months. Guanosine has been reported to promote reflecting platelet formation in melanin-producing pigment cells; however, the process of pigment organellogenesis is still unclear. In the present study, unusual light-reflecting pigment cells were observed upon addition of guanosine to the neural tube culture system, which contained melanosomes specific to melanophores, and reflecting platelets specific to iridophores. Ultrastructural studies suggested that irregularly shaped reflecting platelets were formed from stage II melanosomes (the early stage of melanosome formation) in these unusual pigment cells.

  • A wide variety of Mitf transcript variants are expressed in the Xenopus laevis periodic albino mutant.

    FUKUZAWA TOSHIHIKO

    Genes to Cells （Genes to Cells)  23 （ 8 ） 638 - 648 2018.08

    Research paper (scientific journal), Single Work, Accepted,  ISSN  13569597

    　View Summary

    © 2018 Molecular Biology Society of Japan and John Wiley & Sons Australia, Ltd The periodic albino mutant of Xenopus laevis has been used to study the development of pigment cells because both the retinal pigment epithelium (RPE) and melanophores are affected. In this mutant, “white pigment cells” containing both melanophore-specific and iridophore-specific pigment organelles appear. The present experiments were designed to investigate the structural organization and expression of microphthalmia-associated transcription factor (Mitf) in the mutant since Mitf is known to regulate the development of melanocytes and RPE. The exon structures of X. laevis mitf genes (mitf.L and mitf.S) were defined using newly obtained Mitf transcripts and X. laevis genomic data. Compared to mouse mitf, exons 3 and 6a were absent in X. laevis mitf. The four exons between exons 4 and 6b in X. laevis mitf were named 5α, 5β, 5γ, and 5δ. Exons 5α and 5δ were specific to X. laevis mitf, whereas the continuous exons 5β/γ were identical to exon 5 of mouse mitf. A wide variety of A-Mitf and M-Mitf transcript variants lacking one or more exons were found in X. laevis; however, different types of Mitf transcripts were expressed in the mutant. In addition, white pigment cells and melanophores expressed both the mitf and dopachrome tautomerase (dct) genes.

  • Ferritin H subunit gene is specifically expressed in melanophore precursor-derived white pigment cells in which reflecting platelets are formed from stage II melanosomes in the periodic albino mutant of Xenopus laevis.

    FUKUZAWA TOSHIHIKO

    Cell and Tissue Research 361   733 - 744 2015.02

    Research paper (scientific journal), Single Work, Accepted

  • 文系学生を対象とした新しい生物学学生実験の開発 ー人工赤潮による植物プランクトンの大量増殖の実験ー

    Kensuke Toyoda, Toshihiko Fukuzawa

    Hiyoshi Review of National Science, Keio University  （ 50 ） 3-20 2011.09

    Research paper (bulletin of university, research institution), Joint Work

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Papers, etc., Registered in KOARA 【 Display / hide 】

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Presentations 【 Display / hide 】

  • Pigment expression and pigment organellogenesis in Xenopus laevis.

    福澤利彦

    日本動物学会第90回大阪大会 (大阪市立大学杉本キャンパス) , 

    2019.09
    , 

    Oral presentation (general), 日本動物学会

  • 異質4倍体アフリカツメガエルにおけるMitf遺伝子（A-Mitf, M-Mitf）の転写産物バリアント

    FUKUZAWA TOSHIHIKO

    日本動物学会第88回富山大会 (富山県民会館) , 

    2017.09
    , 

    Oral presentation (general), 日本動物学会

  • Transcript variants of Mitf in the periodic albino mutant of Xenopus laevis are different from those in the wild type.

    FUKUZAWA TOSHIHIKO

    The 22nd International Congress of Zoology (Okinawa Convention Center, Naha City, Okinawa Prefecture, Japan) , 

    2016.11
    , 

    Poster presentation

  • アフリカツメガエル periodic albino 色素突然変異における遺伝子発現の検討

    FUKUZAWA TOSHIHIKO

    日本動物学会第86回大会 (新潟コンベンションセンター) , 

    2015.09
    , 

    Oral presentation (general), 日本動物学会

  • アフリカツメガエル色素突然変異では黒色素胞前駆細胞において虹色素胞特異的な色素顆粒が形成される

    FUKUZAWA TOSHIHIKO

    日本動物学会第85回大会 (東北大学) , 

    2014.09
    , 

    Oral presentation (general), 日本動物学会

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Works 【 Display / hide 】

  • 日吉キャンパス特色GPの取組の理念とその実現に向けて

    FUKUZAWA TOSHIHIKO

    2007.12
    -
    Present
    , 

    Other, Single

  • 生き物の色・模様・形づくり

    FUKUZAWA TOSHIHIKO

    2007.11
    -
    Present
    , 

    Other, Single

  • 商学部における自然科学（生物学）教育

    FUKUZAWA TOSHIHIKO

    2007.09
    -
    Present
    , 

    Other, Single

  • 慶應義塾大学通信教育教科書（新・生物学）

    FUKUZAWA TOSHIHIKO

    2005.04
    -
    Present
    , 

    Other, Joint

  • 両生類における色素パターン形成

    FUKUZAWA TOSHIHIKO

    2002.05
    -
    Present
    , 

    Other, Single

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Courses Taught 【 Display / hide 】

  • INTERNSHIP

    2023

  • INDEPENDENT STUDY (INTERNATIONAL BUSINESS)

    2023

  • GENERAL EDUCATION SEMINAR (DB)

    2023

  • GENERAL EDUCATION SEMINAR (DA)

    2023

  • BIOLOGY 2

    2023

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Courses Previously Taught 【 Display / hide 】

  • 生物学I（実験を含む）

    Keio University

    2016.04
    -
    2017.03
    , 

    Spring Semester

  • 総合教育セミナーD（I類）

    Keio University

    2016.04
    -
    2017.03
    , 

    Full academic year

  • 実践自然科学

    Keio University

    2016.04
    -
    2017.03
    , 

    Autumn Semester

  • 生物学II（実験を含む）

    Keio University

    2016.04
    -
    2017.03
    , 

    Autumn Semester

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Memberships in Academic Societies 【 Display / hide 】

  • 日本動物学会

    　
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Committee Experiences 【 Display / hide 】

  • 1991.12
    -
    2010

    Board of Councillors, 日本色素細胞学会

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