The vomeronasal nerve remains tightly fasciculated in robo-2lox/lox; Nestin-Cre and robo-2lox/lox; OMP-Cre mice. A–D, Coronal sections of olfactory bulbs from adult robo-2+/lox; Nestin-Cre (A), robo-2lox/lox; Nestin-Cre (B), robo-2+/lox; OMP-Cre (C), and robo-2lox/lox; OMP-Cre (D) mice were stained with EC lectin. The vomeronasal nerve is tightly fasciculated in all mice (arrowheads) (n = 3). Scale bar, 125 μm. E–H, Whole-mount high-magnification views of EC2-expressing vomeronasal neuron projections stained with X-gal in adult robo-2+/lox; Nestin-Cre; EC2-tau-lacZ (E), robo-2lox/lox; Nestin-Cre; EC2-tau-lacZ (F), robo-2+/lox; OMP-Cre; EC2-tau-lacZ (G), and robo-2lox/lox; OMP-Cre; EC2-tau-lacZ (H) mice. Tightly fasciculated axon bundles are observed in all mice (n = 6). D, Dorsal; V, ventral; P, posterior; A, anterior.