The Role of Spatially Controlled Cell Proliferation in Limb Bud Morphogenesis
Figure 4
Numerical simulations based on empirical proliferation rates.
Detailed analysis of the simulation with Re = 10−2. (A) The initial limb shape St0 with the measured proliferation pattern converted into source term. High proliferating zones can be found ventrally and distally, as well as a small area dorsally. Medium levels of proliferation can be found distally and ventrally, and a core of low proliferation centrally at the proximal end. (B) The tissue displacement calculated from (A) (green arrows) is fairly uniform surface expansion, resulting in an increased size rather than a shape change. (C) The initial shape St0 (white surface) was grown in silico into the predicted shape pSt1 (green surface), which is larger but shows the same shape. (D) The predicted result pSt1 (green surface) shows significant differences with the empirical measured limb St1 (blue). (E–H) show the same as above for a simulation of a younger E10.5 limb. Despite the simpler limb bud shape (compared to E11.0) this simulation also fails to generate the correct shape change.