Start small: A model for tissue-wide planar cell polarity without morphogens
Fig 5
Cell non-autonomous polarization.
(A) Simulation snapshots showing cell-autonomous (as observed in Drosophila wing) and cell non-autonomous polarization (as observed in mouse epidermis), where the PCP proteins can either self-polarize or not in single cells. (B) Comparison of the distance (left panel) and interface (right panel) between proximal and distal compartments over time for both model versions. In the cell-autonomous case, the compartments have no common interface and remain spatially separated, while in the cell non-autonomous case the interface area is high and their distance fluctuates at values lower than 0.8, indicating mixing. (C) Global polarization of cell non-autonomous PCP model as a function of system size for periodic and left boundary signal configurations. As system size increases, global polarization decreases under both boundary conditions. (D) Final mean angle of tissue polarization for a cell system: under periodic boundary conditions (left, red), the angles are uniformly distributed between
and
; under the left boundary condition (right, blue), the angles are more dispersed along the proximal–distal axis. (E) Final cell polarity vectors for a
system with periodic boundary conditions (left): local alignment occurs within small domains. For the left boundary signal configuration (right), alignment is maintained in the first few columns but dissipates with distance from the boundary. (F) Comparison of global polarization for systems with and without cell proliferation as a function of the number of cells. For fixed tissue sizes, global polarization decreases with system size (red). Uniform cell proliferation enhances global polarization at a higher value 0.93 (green). (G) Simulation output showing preference for alignment along the proximal-distal axis for the uniform cell proliferation configuration.