We first assessed the influence of EWS-Pea3 expression in early post-mitotic DRG neurons on the establishment of afferent projections into the spinal cord using the TaumGFP/+ allele or a Thy1-promoter-driven synaptophysin green fluorescent protein (spGFP) with an expression profile restricted to DRG sensory neurons at embryonic day (E) 13.5 (Thy1spGFP; [25]) (Figure 3).