Fig. S6

Differential expression of delta ligand genes within the pallial germinal zone. (A) Cross-section at the level indicated on the scheme showing the distribution of deltaA mRNA (in situ hybridization, blue). Boxed areas are illustrated from sections triple-stained for deltaA (fluorescent in situ hybridization, magenta), GFP (RG, immunocytochemistry, gray) and MCM5 (immunocytochemistry, green). a2 and a22 deltaA is expressed by proliferating RG (type II cells, yellow arrow, first panel) in the dorsomedial region of the pallium (Dm), and proliferating neuronal precursors (GFAP negative, MCM5 positive) (type III cells) at the pallial-subpallial junction (yellow arrows, second panel). (B) Cross-section at the level indicated on the scheme showing the expression of deltaB mRNA (in situ hybridization, blue). Boxed areas are illustrated from sections triple stained as above but with the deltaB probe (magenta). (b2,b22) deltaB is expressed by type III cells (yellow arrows, first panel) and proliferating RG (type II cells, white arrow, first panel) in Dm, and by type III cells at the pallial-subpallial junction. (C) Cross-section at the level indicated on the scheme showing the expression of deltaD mRNA. The boxed area is illustrated from a section triple stained as above but with the deltaD probe (magenta). (c2) deltaD expression is found exclusively on type III cells at the pallial-subpallial junction. (D) Quantification of the percentage of different cell types in terms of delta expression (n=665 cells). Scale bars: 20 μm. All pictures are single optical planes.