Physical limits of flow sensing in the left-right organizer
Abstract
Fluid flows generated by motile cilia are guiding the establishment of the left-right asymmetry of the body in the vertebrate left-right organizer. Competing hypotheses have been proposed: the direction of flow is sensed either through mechanosensation, or via the detection of chemical signals transported in the flow. We investigated the physical limits of flow detection in order to clarify which mechanisms could be reliably used for symmetry breaking. We integrated parameters describing cilia distribution and orientation obtained in vivo in zebrafish into a multiscale physical study of flow generation and detection. Our results show that the number of immotile cilia is too small to ensure robust left and right determination by mechanosensing, given the large spatial variability of the flow. However, motile cilia could sense their own motion by a yet unknown mechanism. Finally, transport of chemical signals by the flow can provide a simple and reliable mechanism of asymmetry establishment.
Article and author information
Author details
Funding
Human Frontier Science Program (CDA00032/2010-C)
- Julien Vermot
Labex (ANR-10-LABX-0030-INRT)
- Rita R Ferreira
- Julien Vermot
Agence Nationale de la Recherche (ANR-13-BSV1-0016)
- Julien Vermot
Agence Nationale de la Recherche (ANR- 12-ISV2-0001)
- Julien Vermot
Agence Nationale de la Recherche (ANR-2010-JCJC-1510-01)
- Willy Supatto
Agence Nationale de la Recherche (ANR-11-EQPX-0029)
- Willy Supatto
Javna Agencija za Raziskovalno Dejavnost RS (grant J1-5437)
- Andrej Vilfan
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: Animal experiments were approved by the Animal Experimentation Committee of the Institutional Review Board of the IGBMC.
Copyright
© 2017, Ferreira 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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