Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology


LAST UPDATE 2020/06/11

  • 研究者氏名
    Researcher Name

    若林憲一 Ken-ichi WAKABAYASHI
    准教授 Associate Professor
  • 所属
    Professional Affiliation

    Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology

    Molecular bioscience
  • 研究キーワード
    Research Keywords

    Eukaryotic cilia and flagella
    Motor proteins
    Chlamydomonas reinhardtii
Research Subject
Molecular basis of construction and motility regulation of eukaryotic cilia and flagella

研究の背景 Background


Eukaryotic cilia and flagella are hair-like organelles that beat and generate fluid flow around cells. They are well known as a force generator for small organisms or sperms; in addition, they exist several kinds of organs in human body and play important roles. There are many kinds of diseases caused by ciliary/flagellar dysfunction, called “primary ciliary dyskinesia (PCD)”. To understand the mechanism underlying PCD, it is important to understand the molecular basis of construction of cilia/flagella and that of their motility regulation.

研究の目標 Outcome


We use the unicellular green alga Chlamydomonas reinhardtii as a model to study eukaryotic cilia/flagella (Fig. 1a). The inner structure of cilia/flagella is conserved throughout evolution (called “9+2” structure), and the knowledge obtained from Chlamydomonas can be applied to other organisms including human. Currently we are running two projects: 1) construction of periodic structure of flagella (Fig. 2) and 2) motility regulation of flagella for Chlamydomonas phototaxis.

研究図Research Figure

Fig.1. a) Chlamydomonas reinhardtii cell. It has two flagella, one chloroplast and one eyespot. Bar: 10 µm. b) The 9+2 structure of Chlamydomonas flagellum. Bar: 100 nm. Fig.2. Schematic of construction of 24-nm periodicity of outer-arm dynein on 9+2 structure. The outer-dyneinarm docking complex (ODA-DC) molecules bind to each other on a microtubule in an end-to-end manner and make a 24-nm periodicity at the base of outer-arm dynein. Fig.3.Phototaxis dish assay picture of Chlamydomonas cells after treatment with an oxidant or an anti-oxidant. They switch the sign of phototaxis in a redoxdependent manner.

文献 / Publications

J. Cell Biol., 173, 743 (2006). Cell Motil Cytoskeleton, 66, 736 (2009). P.N.A.S., 108, 11280 (2011). J. Cell Biol., 199, 151(2012). P.N.A.S. 111, 9461 (2014).