Mechanical control of rhythmic flagellar beating motions

2022 Fiscal Year Final Research Report

• Project/Area Number: 19H02566
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 28040:Nanobioscience-related
• Research Institution: Kindai University
• Principal Investigator: Nishiyama Masayoshi 近畿大学, 理工学部, 准教授 (10346075)
• Co-Investigator(Kenkyū-buntansha): 八木 俊樹 県立広島大学, 生命環境学部, 教授 (40292833) ; 今井 洋 大阪大学, 大学院理学研究科, 助教 (60391869) ; 松浦 宏治 岡山理科大学, 工学部, 准教授 (70443223)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 鞭毛 / 高圧力顕微鏡 / 運動マシナリ / 分子操作 / ナノバイオ

Outline of Final Research Achievements

The beating of eukaryotic flagella depends on the sliding movements between microtubules powered by dynein. In flagella of most organisms, microtubule sliding is regulated by the internal structure of flagella comprising the central pair of microtubules (CP) and radial spokes (RS). Chlamydomonas paralyzed-flagella (pf) mutants lacking CP or RS are non-motile under physiological conditions. Here, we show that high hydrostatic pressure induces vigorous flagellar beating in pf mutants. The beating pattern at 40 MPa was similar to that of wild type at atmospheric pressure. In addition, at 80 MPa, flagella underwent an asymmetric-to-symmetric waveform conversion, similar to the one triggered by an increase in intra-flagella Ca2+ concentration during cell’s response to strong light. Thus, our study establishes that neither beating nor waveform conversion of flagella requires the presence of CP/RS in the axoneme.

Free Research Field

ナノバイオサイエンス

Academic Significance and Societal Importance of the Research Achievements

ヒトの体の中ではたらく繊毛や鞭毛が動かなくなると,「繊毛病」と呼ばれる病気の症状が現れる。例えば, 精子の鞭毛が動かなくなると不妊症になる。今回，調べた「緑藻クラミドモナス」は，ヒトの繊毛や鞭毛とほぼ同じ仕組みで動いている。今回, 明らかにした静水圧による鞭毛運動の活性化法を応用すれば，なんらかの理由で動かないヒトの鞭毛や繊毛の不調を回復させ，不妊治療などにつなげられる可能性が出てくる。