Figure 4.

Tissue growth simulation by coupling the vertex dynamics model and srFCD model. (A) Tissue growth simulation during Drosophila wing disk development using the two-dimensional vertex dynamics model in which each cell has a simplified cell cycle regulator whose checkpoint is controlled by the srFCD model, namely the IF or DT model. The Dpp morphogen, the input for the srFCD model, is produced at the source cells adjacent to the anterior-posterior (AP) boundary. (B and C) Simulation results when the Dpp source intensity exponentially increases (B) and periodically changes (C). (Top panels) Temporal profiles of the cell numbers in the IF model (blue curves), in the DT model (red curves), and Dpp source intensity (dashed green curves). (Bottom panels) Representative images at three different time points (corresponding to the dashed lines in the above panels). Color indicates cellular Dpp intensity. Although the IF and DT models gave almost the same results for exponential inputs (B), only the IF model gave biphasic tissue growth for periodic inputs (C). To see this figure in color, go online.