Choline acetyltransferase (ChAT)-positive Lis1+/− sympathetic preganglionic (SPNs) and somatic motor neurons (SMNs) do not separate completely during development. A,C,E,G: E13.5 (A), 14.5 (C), 17.5 (E), and P0 (G) Lis1+/+ SPNs are found in the intermediolateral horn (IML). As development proceeds, the distance between the SPNs and SMNs increases (A,
). B,D,F,H: The separation between SPNs and SMNs is smaller in E13.5 Lis1+/− (B,
) than in Lis1+/+ mice and also at E14.5 (D), E17.5 (F), and P0 (H). Scale bar = 100 μm in A (applies to A–H).