Ciliary chemosensitivity is enhanced by cilium geometry and motility

  1. David Hickey
  2. Andrej Vilfan  Is a corresponding author
  3. Ramin Golestanian  Is a corresponding author
  1. Max Planck Institute for Dynamics and Self-Organization, Germany

Abstract

Cilia are hairlike organelles involved in both sensory functions and motility. We discuss the question of whether the location of chemical receptors on cilia provides an advantage in terms of sensitivity and whether motile sensory cilia have a further advantage. Using a simple advection-diffusion model, we compute the capture rates of diffusive molecules on a cilium. Because of its geometry, a non-motile cilium in a quiescent fluid has a capture rate equivalent to a circular absorbing region with ~4x its surface area. When the cilium is exposed to an external shear flow, the equivalent surface area increases to ~6x. Alternatively, if the cilium beats in a non-reciprocal way in an otherwise quiescent fluid, its capture rate increases with the beating frequency to the power of 1/3. Altogether, our results show that the protruding geometry of a cilium could be one of the reasons why so many receptors are located on cilia. They also point to the advantage of combining motility with chemical reception.

Data availability

All data generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided for Figures 3 and 4.

Article and author information

Author details

  1. David Hickey

    Living Matter Physics, Max Planck Institute for Dynamics and Self-Organization, Göttingen, Germany
    Competing interests
    The authors declare that no competing interests exist.
  2. Andrej Vilfan

    Living Matter Physics, Max Planck Institute for Dynamics and Self-Organization, Göttingen, Germany
    For correspondence
    andrej.vilfan@ds.mpg.de
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-8985-6072
  3. Ramin Golestanian

    Department of Living Matter Physics, Max Planck Institute for Dynamics and Self-Organization, Goettingen, Germany
    For correspondence
    Ramin.Golestanian@ds.mpg.de
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3149-4002

Funding

Max-Planck-Gesellschaft

  • David Hickey
  • Andrej Vilfan
  • Ramin Golestanian

Javna Agencija za Raziskovalno Dejavnost RS (P1-0099)

  • Andrej Vilfan

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Raymond E Goldstein, University of Cambridge, United Kingdom

Version history

  1. Received: January 7, 2021
  2. Preprint posted: January 14, 2021 (view preprint)
  3. Accepted: August 3, 2021
  4. Accepted Manuscript published: August 4, 2021 (version 1)
  5. Version of Record published: August 25, 2021 (version 2)

Copyright

© 2021, Hickey 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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  1. David Hickey
  2. Andrej Vilfan
  3. Ramin Golestanian
(2021)
Ciliary chemosensitivity is enhanced by cilium geometry and motility
eLife 10:e66322.
https://doi.org/10.7554/eLife.66322

Share this article

https://doi.org/10.7554/eLife.66322

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