Ngn2 progenitors sequentially generate Tbr2- and Tbr1-expressing neurons during embryonic development. (A-C) Antigenic properties of Neurog2-derived OB juxtaglomerular neurons of P21 Ngn2CreERT2 × TaukiGFP mice. The recombination was induced at E13.5 (A), E17.5 (C) and at birth (E) by a single injection of tamoxifen. Error bars indicate S.E.M. (D-I) High field images of the pattern of expression of the markers used to identify subpopulations of juxtaglomerular OB neurons. All images were acquired from animals induced at birth and sacrificed at P21. Arrows point to cells negative for the markers tested. Asterisks indicate cells positive for Tbr2 and Tbr1. Scale bar: 50 μm in all panels. CB, calbindin; CR, calretinin; NeuN, neuronal nuclear antigen; Tbr1 and Tbr2, T-box protein 1 and 2; TH, tyrosine hydroxylase.