Dynamic curvature regulation accounts for the symmetric and asymmetric beats of Chlamydomonas flagella
Abstract
Cilia and flagella are model systems for studying how mechanical forces control morphology. The periodic bending motion of cilia and flagella is thought to arise from mechanical feedback: dynein motors generate sliding forces that bend the flagellum, and bending leads to deformations and stresses, which feed back and regulate the motors. Three alternative feedback mechanisms have been proposed: regulation by the sliding forces, regulation by the curvature of the flagellum, and regulation by the normal forces that deform the cross-section of the flagellum. In this work, we combined theoretical and experimental approaches to show that the curvature control mechanism is the one that accords best with the bending waveforms of Chlamydomonas flagella. We make the surprising prediction that the motors respond to the time derivative of curvature, rather than curvature itself, hinting at an adaptation mechanism controlling the flagellar beat.
Article and author information
Author details
Reviewing Editor
- Raymond E Goldstein, University of Cambridge, United Kingdom
Version history
- Received: November 22, 2015
- Accepted: May 8, 2016
- Accepted Manuscript published: May 11, 2016 (version 1)
- Version of Record published: June 28, 2016 (version 2)
Copyright
© 2016, Sartori et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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