Fig. S4

Craniofacial defects in bcl9 and pygo1/2 mutants.

(A-F) Alcian blue staining of the pharyngeal cartilage of 5 dpf wildtype, bcl9^Δ29, and double homozygous pygo1^Δ5;pygo2^Δ1 embryos shown in ventral (A,C,E) and lateral (B,D,F) views, anterior to the left. bcl9 and pygo1/2 mutants have severe malformations of the pharyngeal apparatus with fusions defect of the ceratohyal (ch) and ceratobranchial 1 (cb1) arches and miss-shaped Meckel's (m) and palatoquadrate (pq) cartilage. Scale bars, 100 µm. (G-L) SPIM-based brightfield imaging of wildtype-appearing siblings and homozygous pygo1^Δ5;pygo2^Δ1 embryos. Note absence of swim bladder (sb) and craniofacial defects in double-mutants (G,J). Ventral close-up of cardiac region (square in H,K, enlarged in I,L with red outline depicting the heart), showing abnormal heart looping and smaller bulbus arteriosus region in homozygous mutants. (M) Quantification of phenotypes in four individual pygo1^Δ5/wt x pygo2^Δ1/wt crosses reveal defects in 7-18% of all embryos. Genotyping of phenotypic embryos revealed phenotype occurrence in homozygous pygo2^Δ1 mutants in combination with homozygous or heterozygous pygo1^Δ5 mutation. (N-P) MZpygo1^Δ5 (N) and homozygous pygo2^Δ1 (O) mutants, as well as mutants carrying a homozygous pygo1^Δ5 combined with heterozygous pygo2^Δ1 alleles (P) are viable and fertile; lateral views, anterior to the left.