Fig. 4
From: Strategies for assembling columns and layers in the Drosophila visual system
Targeting to the outer or inner medulla. A diagram of medulla development at an early pupal stage (~12 hours after puparium formation [h APF]). Lamina growth cones expressing CadN and Sema-1a are prevented from innervating the inner medulla through repulsive interactions with PlexA expressing medulla tangential cells (MeT), and interactions with other CadN expressing processes in the outer medulla. Mi1 = a medulla instrinsic 1 neuron. The asterisk indicates the youngest lamina neuron axons within the medulla neuropil