We have shown that TSC plays a key role in controlling the timing of neuronal differentiation in Drosophila through the conserved insulin receptor (InR)/Tor kinase signaling pathway (Bateman & McNeill, 2004). The goal of our current research is to determine the mechanism by which TSC regulates the timing of neuronal differentiation. To uncover the pathway(s) downstream of TSC in the temporal control of neuronal differentiation we are taking complementary approaches. 1) Analysis of minimal regions of neuronal promoters responsive to TSC. 2) Identification and analysis of genes regulated by TSC to control neural differentiation. We find that InR/TSC signaling regulates the transcription and phosphorylation state of the ETS transcription factor, Pointed P2. We define a 2.5kb region of the ELAV neuronal enhancer region that responds to TSC. We have further used transgenic RNAi analysis in vivo to test if candidate genes that are regulated by TSC in a screen of S2 cells have a role in the regulation of neuronal differentiation in vivo, and have identified candidate genes that regulate neuronal differentiation timing in vivo.