Figure 4: Comparisons of the simulated and actual Tribolium growth zones.
From: Changing cell behaviours during beetle embryogenesis correlates with slowing of segmentation
We built a computational model of growth zone elongation during the 18–20-h period of rapid segment addition in Tribolium. Initial growth zone length and cell counts for the model (a) matched those measured in typical 18 h embryos (b). Elongation in the modelled growth zone depends on cell rearrangements (chosen to mimic those observed by Sarrazin, et al.14, in the earlier Tribolium embryo)—cells do not divide in the model. Over the modelled time window, the simulated germ band forms five additional segments (c), resembling the actual embryo (d). While we do not attempt to model the mechanisms leading to cell rearrangements or claim that cell rearrangements in the simulation exactly reflect those in the actual embryo, the simulation is consistent with a model in which cell rearrangements rather than a highly proliferative posterior growth zone drive axial elongation. Scale bar, 100 μm.
