Shuichi Hayashi    Department   Kawasaki Medical School  Kawasaki Medical School, Department of Anatomy,    Position   Associate Professor
Article types	原著
Language	English
Peer review	Peer reviewed
Title	Mechanism of flagellar oscillation: Bending-induced switching of dynein activity in elastase-treated axonemes of sea urchin sperm.
Journal	Formal name：Journal of Cell Science
Domestic / Foregin	Foregin
Volume, Issue, Page	121(7),pp.2833-2843
Author and coauthor	Hayashi, S. and Shingyoji, C.
Authorship	Lead author
Publication date	2008
Summary	Oscillatory movement of eukaryotic flagella is caused by dynein-driven microtubule sliding in the axoneme. The mechanical feedback from the bending itself is involved in the regulation of dynein activity, the main mechanism of which is thought to be switching of the activity of dynein between the two sides of the central pair microtubules. To test this, we developed an experimental system using elastase-treated axonemes of sperm flagella, which have a large Ca(2+)-induced principal bend (P-bend) at the base. On photoreleasing ATP from caged ATP, they slid apart into two bundles of doublets. When the distal overlap region of the slid bundles was bent in the direction opposite to the basal P-bend, backward sliding of the thinner bundle was induced along the flagellum including the bent region. The velocity of the backward sliding was significantly lower than that of the forward sliding, supporting the idea that the dynein activity alternated between the two sides of the central pair on bending. Our results show that the combination of the direction of bending and the conformational state of dynein-microtubule interaction induce the switching of the dynein activity in flagella, thus providing the basis for flagellar oscillation.