Figure 1. Schematic representation of the DV and AP organizers and boundaries.

A: The DV organizer develops symmetrically with respect to the D and V compartments and acting as a fence prevents cells at the compartments bulk from mixing. The width of the DV organizer population is typically restricted to two cells. The DV boundary (blue dashed line) develops at the middle of the DV organizer and confer distinct mechanical properties to cells. B: The AP organizer is located at the anterior compartment. Importantly, the task of maintaining cells from opposite compartments separated relies on the boundary (blue dashed line) in this case (see text).