Notch signaling promotes cell proliferation of neural crest derivatives. (A-C) The DRG (arrows) are NCC-derived structures, as evident by X-Gal staining of Wnt1Cre;R26R, Wnt1Cre;R26R;RosaNotch, and Wnt1Cre;R26R;RBP-Jf/f E10.5 sections. (n=8 for each genotype) (D-G) Notch activation results in increased NCC proliferation, while Notch pathway inactivation results in significant reduction of NCC proliferation in the DRG, as determined by BrdU incorporation (arrows), compared to Wnt1Cre-negative control littermates. (n=6 for each genotype) * p ≤ 0.01