Fig. 1

Loss of function mutations in col11a2 cause vertebral fusion defects. (A) Schematic of the wildtype Col11a2 protein, showing its domain structure and the position at which gRNAs were targeted to generate the col11a2L642* mutation. This allele encodes a truncated protein, illustrated on the right. (B) Strategy used to create the col11a2del allele. Two gRNAs were targeted to the 5? and 3? ends of the col11a2 gene, to delete the intervening 45 kb genomic locus. The resulting col11a2del allele encodes a 13 amino acid peptide. (C) Alizarin red staining of adult wildtype and col11a2L642*/L642* zebrafish, showing vertebral fusion in the posterior spine of col11a2L642*/L642*mutants. Schematic to the right of each image highlights the structure of normal versus fused vertebrae. (D) In vivo staining with alizarin red at 16dpf and calcein at 21dpf labels the developing vertebrae. Fusions in col11a2L642*/L642* and col11a2del/del animals first form along the ventral edge of the spine (arrowheads) and proceed dorsally (asterisks). ?CT scans at 8 wpf (weeks post fertilization) demonstrating mature fused vertebrae in each animal (asterisks).