The control of EGF signaling and cell fate in the Drosophila abdomen.

How cells integrate both patterning and signaling information to select between distinct cell fates is a fundamental problem in developmental biology. In this short review, I focus on recent findings of how the Hox and senseless patterning genes regulate epidermal growth factor (EGF) signaling and cell fate within the Drosophila abdomen. In Li-Kroeger et al., we described how a Hox and Senseless transcription factor competition functions as a molecular switch on a cis-regulatory element in the rhomboid (rho) gene to control EGF signaling within the peripheral nervous system (PNS). Here, I discuss an additional implication of these findings: that rho contains at least two cis-regulatory elements to control EGF secretion from the PNS, each to induce a different cell fate.