title: Active phase and amplitude fluctuations of flagellar beating.
abstract: The eukaryotic flagellum beats periodically, driven by the oscillatory dynamics of molecular motors, to propel cells and pump fluids. Small but perceivable fluctuations in the beat of individual flagella have physiological implications for synchronization in collections of flagella as well as for hydrodynamic interactions between flagellated swimmers. Here, we characterize phase and amplitude fluctuations of flagellar bending waves using shape mode analysis and limit-cycle reconstruction. We report a quality factor of flagellar oscillations Q = 38.0 ± 16.7 (mean ± s.e.). Our analysis shows that flagellar fluctuations are dominantly of active origin. Using a minimal model of collective motor oscillations, we demonstrate how the stochastic dynamics of individual motors can give rise to active small-number fluctuations in motor-cytoskeleton systems.
authors.affiliation: Max Planck Institute for the Physics of Complex Systems, 01187 Dresden, Germany and Institute for Advanced Study, Tsinghua University, 100084 Beijing, China.
authors.forename: Rui
authors.initials: R
authors.lastname: Ma
authors.affiliation: Max Planck Institute for the Physics of Complex Systems, 01187 Dresden, Germany.
authors.forename: Gary S
authors.initials: GS
authors.lastname: Klindt
authors.affiliation: Department of Bioengineering, Stanford University, Stanford, California 94305, USA.
authors.forename: Ingmar H
authors.initials: IH
authors.lastname: Riedel-Kruse
authors.affiliation: Max Planck Institute for the Physics of Complex Systems, 01187 Dresden, Germany.
authors.forename: Frank
authors.initials: F
authors.lastname: Jülicher
authors.affiliation: Max Planck Institute for the Physics of Complex Systems, 01187 Dresden, Germany.
authors.forename: Benjamin M
authors.initials: BM
authors.lastname: Friedrich
mesh_terms: D005407:Flagella / Q000502:physiology*; D008954:Models, Biological; D013269:Stochastic Processes; D013550:Swimming