Figure 7

OR-specific subpopulations of OSN axons show evidence of regional segregation within the olfactory nerve. Sagittal sections of P2-lacZ/M72-GFP embryos. (A-C, A'-C') Z-series projections taken from sagittal sections of E16 P2-lacZ or M72-GFP mice. (A) Low-powered montage of the olfactory nerve pathway of a heterozygous P2-lacZ mouse; (A') high-magnification image of the left-hand boxed area in (A); (A'') high magnification image of the right-hand boxed area in (A), showing the P2⁺ axons approaching the inner nerve layer of the OB. (B) Low-powered montage of the olfactory nerve pathway of a homozygous M72-GFP mouse; (B') high-magnification image of the boxed area in (B). Open arrowheads indicate incomplete homotypic fasciculation. (C) Low-powered montage of the olfactory nerve pathway of a heterozygous P2-lacZ mouse; (C') high-magnification image of the boxed area in (C). Orientation compass shown in (A). Scale bars in (A, B, B', C, C') = 100 μm and in (A', A'') = 5 μm.