Figure 7.

Model for the regulation of abdominal NB death by abdA and N. Early expression of abdA in NBs sets up the abdominal identity of the NBs. This influences the lineages they produce, and possibly their competence to re-express abdA later in embryogenesis in response to N. The abdominal lineages, including neurons and glia produce Dl, which activates N in the NB. N then influences both NB specification and activates a later pulse of abdA. abdA, working together with as yet unidentified timing and cell identity-specific signals, turns on the activity of Enh1, activating rpr, grim and skl to induce cell death