Direct Measurement of Inter-doublet Elasticity in Flagellar Axonemes

DOI Web Site Web Site PubMed 被引用文献5件 参考文献67件
  • Minoura Itsushi
    National Institute for Basic Biology, Okazaki 444-8585, Japan Department of Biological Sciences, Graduate School of Science, University of Tokyo 113-0033, Japan
  • Yagi Toshiki
    Department of Biological Sciences, Graduate School of Science, University of Tokyo 113-0033, Japan
  • Kamiya Ritsu
    Department of Biological Sciences, Graduate School of Science, University of Tokyo 113-0033, Japan National Institute for Basic Biology

この論文をさがす

抄録

The outer doublet microtubules in ciliary and flagellar axonemes are presumed to be connected with each other by elastic links called the inter-doublet links or the nexin links, but it is not known whether there actually are such elastic links. In this study, to detect the elasticity of the putative inter-doublet links, shear force was applied to Chlamydomonas axonemes with a fine glass needle and the longitudinal elasticity was determined from the deflection of the needle. Wild-type axonemes underwent a high-frequency, nanometer-scale vibration in the presence of ATP. When longitudinal shear force was applied, the average position of the needle tip attached to the axoneme moved linearly with the force applied, yielding an estimate of spring constant of 2.0 (S.D.: 0.8) pN/nm for 1 μm of axoneme. This value did not change in the presence of vanadate, i.e., when dynein does not form strong cross bridges. In contrast, it was at least five times larger when ATP was absent, i.e., when dynein forms strong cross bridges. The measured elasticity did not significantly differ in various mutant axanemes lacking the central-pair microtubules, a subset of inner-arm dynein, outer-arm dynein, or the radial spokes, although it was somewhat smaller in the latter two mutants. It was also observed that the shear displacement in an axoneme in the presence of ATP often took place in a stepwise manner. This suggests that the inter-doublet links can reversibly detach from and reattach to the outer doublets in a cooperative manner. This study thus provides the first direct measure of the elasticity of inter-doublet links and also demonstrates its dynamic nature.

収録刊行物

被引用文献 (5)*注記

もっと見る

参考文献 (67)*注記

もっと見る

キーワード

詳細情報 詳細情報について

問題の指摘

ページトップへ