Vu2019 - Planarian double-head regeneration

This spatio-temporal model explores tissue polarity re-organization during planarian double-head formation upon regeneration with beta-catenin-1 RNAi treatment. Initial conditions for A and M polarity fields are chosen near the wild type pattern and the first 100 time steps are used to establish the typical wild type splay pattern. The induction of the ectopic head occurs at time-step 100 (interpreted as tail amputation time) at the position where the former tail was (right end), subsequently affects the nearby tissue with some lag and then re-polarizes the posterior half of the tissue from time-step 200 onward. Of these polarity fields, A represents the anterior-posterior polarization system provided by the core PCP pathway, M represents the medio-lateral polarization system provided by the Ft/Ds pathway and P represents the resulting superimposed and normalized polarization. P can be compared to the observable polarity data of ciliary rootlets. This simulation reproduces Figure 4D of the referenced paper. Parameter values correspond to the beta-catenin-1(RNAi) pattern as given in Table S2 of the referenced paper. The model file is in MorpheusML format and can be opened in the free, open-source multicellular modeling software Morpheus (https://morpheus.gitlab.io) to simulate the time course (movie) of the spatio-temporal dynamics.