Fig. 8. Laminar specificity and synapse formation by Pcdh--deficient neurons rescued from apoptosis. (A-D) Sections from retinas mutant for Bax (Chx10-Cre;Pcdh- ^fcon3/+ Bax^-/-), Pcdh- (Chx10-Cre;Pcdh- ^fcon3/fcon3 Bax^+/-), both (Chx10-Cre;Pcdh- ^fcon3/fcon3 Bax^-/-) or neither (Chx10-Cre;Pcdh- ^+/fcon3 Bax^+/-). Sections were stained with anti-bassoon (red) and Po-pro1 (blue). Thickness of IPL and INL are similar in Bax mutants and Bax, Pcdh- double mutants; both are thicker than those in Pcdh- mutants. (E-L) High power images of OPL (E,G,I,K) and IPL (F,H,J,L) from retinas in A-D. Density of synaptic puncta is similar in Bax mutants and Bax, Pcdh- double mutants (see Fig. S2 in the supplementary material for quantification). (M,N) Chx10-Cre;Pcdh- ^fcon3/fcon3 Bax^-/- mutants immunostained for ChAT (red) and vGluT3 (green) (M) or synaptotagmin 2 (SytII, red), and G13 (green) (N). All processes make lamina-specific arbors (compare with Fig. 7) and disruptions seen in Pcdh- single mutants are absent in double mutants. Scale bars: 100 µm in A-D; 10 µm in E-L; 50 µM in M,N.