Physical limits of flow sensing in the left-right organizer

• Published in: eLife Vol. 6; p. 556
• Main Authors: Ferreira, Rita R, Vilfan, Andrej, Jülicher, Frank, Supatto, Willy, Vermot, Julien
• Format: Journal Article
• Language: English
• Published: England eLife Sciences Publications Ltd 14-06-2017; eLife Sciences Publication; eLife Sciences Publications, Ltd
• Subjects: Animals; Asymmetry; Bioengineering; Biological Physics; Body Patterning; Cilia; Cilia - physiology; Computational and Systems Biology; Danio rerio; Development Biology; Developmental Biology and Stem Cells; Embryo, Nonmammalian - cytology; Embryo, Nonmammalian - physiology; Embryos; fluid flow; Functional Laterality; Gene expression; Gene Expression Regulation, Developmental; Hydrodynamics; Hypotheses; Imaging; Life Sciences; low reynolds number; Mechanotransduction; motile cilia; multiscale analysis; patterning; Physics; Signal Transduction; Spatial distribution; Symmetry; Zebrafish; Zebrafish - embryology; Zebrafish - physiology; Zebrafish Proteins - metabolism; computational biology; systems biology; stem cells; multiscale analysis; fluid flow; developmental biology; motile cilia; zebrafish; low reynolds number; patterning
• ISSN: 2050-084X; 2050-084X
• DOI: 10.7554/elife.25078

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 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.