Figure 5. Tracing experiments reveal less interneurons invading the striatum after postmitotic loss of Nkx2-1 function.
(A and B) Coronal sections through the striatum of P0 Lhx6-Cre;Nkx2-1Fl/+;Rosa-YFP control (A) and Lhx6-Cre;Nkx2-1Fl/Fl;Rosa-YFP mutant (B) mice showing YFP expression. YFP is also detected in scattered blood vessels, as previously reported (Fogarty et al., 2007).
(C) Quantification of the number of YFP-expressing cells in the striatum of P0 Lhx6-Cre;Nkx2-1Fl/+;Rosa-YFP control and Lhx6-Cre;Nkx2-1Fl/Fl;Rosa-YFP mutant mice. Histograms show average ± s.e.m. 889.31 ± 79.03 (YFP control); 664.12 ± 58.40 (YFP mutant). * p < 0.05, t-test.
(D) Schematic diagram of the focal electroporation experiment. The number of Gfp-expressing cells was counted in a fixed volume of the cortex and striatum (black boxes) and the ratio between these populations was determined for each slice
(E–F) Migration of MGE-derived cells in E13.5 Lhx6-Cre;Nkx2-1Fl/+;Rosa-YFP control (E) and Lhx6-Cre;Nkx2-1Fl/Fl;Rosa-YFP mutant (F) slices. Occasionally, Gfp-expressing cells accumulated in the piriform cortex of mutant slices. Dotted lines indicate the limits of the organotypic slices.
(G) Ratio of Gfp-expressing cells in the quantified region of the cortex and striatum for each individual E13.5 Lhx6-Cre;Nkx2-1Fl/+;Rosa-YFP control and Lhx6-Cre;Nkx2-1Fl/Fl;Rosa-YFP mutant slices. Average ± s.e.m. 2.55 ± 0.41 (control); 6.80 ± 1.22 (mutant). *** p < 0.001, t-test. Number of Gfp-expressing cells in the striatum (30.38 ± 4.03, control; 12.20 ± 3.80, mutant. *** p < 0.001, t-test) and cortex (76.80 ± 12.76, control; 84.20 ± 21.20, mutant) of electroporated slices.
CPu, caudate putamen; H, hippocampus; LGE, lateral ganglionic eminence; MGE, medial ganglionic eminence; NCx, neocortex; PCx, piriform cortex; Str, striatum.
Scale bar equals 100 µm (A and B) and00 µm (E and F).