Formation of the Long Range Dpp Morphogen Gradient
Figure 1
Modeling of the effect of receptor mutant clones on Dpp gradient formation in different transport scenarios.
Modeling the effects of GOF (A,B,C) and LOF (D,E,F) receptor mutant clones on Dpp gradient formation in different transport scenarios: RMT (A,D), RED with 80% of Dpp receptor-bound (B,E) and RED with 80% of Dpp unbound (C,F). The position x ranges from −L to L, where L is the half length of the wing pouch. The thick solid line represents the total Dpp profile, the thin solid line internal Dpp, the dotted line receptor-bound Dpp, and the dashed line external unbound Dpp. Dpp levels are always expressed in arbitrary units. The dashed vertical lines show the source boundaries (−15%L and 0), and the clones are located between 5%L to 15%L (A–C) and 15%L to 25%L (D–F). In the GOF clones we assume a 10-fold increase of receptor levels, and in LOF clones we assume nil receptors. GOF clones lead to an increase of Dpp levels inside the clones in all different transport scenarios (A,B,C), and therefore can be distinguished only quantitatively. In LOF clones, however, RMT can also be distinguished qualitatively from the extracellular movement models.