Figure 1

Two representations of the spatial information in the model. (A): The first representation is provided by the explicit use of the spatial position x at the A-P axis of the embryo. The panel shows the Cad spatial profile from time class 6 of cleavage cycle 14A (red line) and exponentially approximated individual Bcd profiles in the ensemble (black lines). The vertical dashed lines indicate positions of eleven nuclei in cleavage cycle 13 and in the given spatial range. (B): The second representation is provided by the use of 2D parameter (v^Bcd, v^Cad), specifying values of Bcd and Cad concentrations in Eqs. (2). This parameter defines a point on the Bcd-Cad plane. The dots in the panel represent the points whose Cad components come from the intersection points between the dashed lines and the Cad profile in (A), and the Bcd components from the intersections of dashed lines with the Bcd profiles in (A). Therefore, these dots describe the actual values of the external input (v^Bcd, v^Cad) in Eqs. (2) at late times and for the selected eleven spatial positions. The solid line in the panel is the curve parameterized by x from the spatial range, where is the median Bcd profile and v^Cad(x) is the Cad profile from (A), showing how the variation of spatial position x in the model with the fixed Bcd profile is read on the Bcd-Cad plane.