Fig. 3.

Formation of a gradient by the SGA model. The SGA was tested using the case of gradient formation in a 1D system. The gradient forms via anterior production, diffusion, and uniform degradation. Natural log of Bcd molecules is plotted for the anterior region (0<x<100; total egg length is 500 μm). Posterior regions were omitted due to low molecule copy numbers. A comparison of the results of the SGA simulation with analytical prediction (Materials and methods) is shown. The simulation result was linearly fit