Fig. 3. Chm is Cs-lam3/4/5. (A) Schematic of AFLP and SSCP mapping showing a predicted alpha laminin gene on paired scaffolds 312 and 44 in C. savignyi. (B-D) Whole-mount in situ hybridization for Cs-lam3/4/5 message showing notochord-specific expression in (B) late neurula, (C) mid-tailbud and (D) late tail extension stages. (E) Sense control and (F) decreased expression in a chm/chm embryo. (G) Embryo injected with control morpholino. (H,I) Cs-lam3/4/5 morphant embryos showing the range of phenotypes observed. (J) bra:GFP expressing embryo co-injected with Cs-lam3/4/5 morpholino and red fluorescent dextran as an injection marker. Note the disorganized notochord boundary, the dispersed bra:GFP-expressing cells in the tail (blue arrowheads) and the characteristic epidermal protrusion (yellow bracket). (K) Schematic of Cs-lam3/4/5 domain structure showing a 9 amino acid insertion in chm and a frameshift predicted to cause to premature termination in chm³⁵. The antigen used to make the Cs-lam3/4/5 antibody is indicated. (L) Chromatograms showing the chm³⁵ frameshift in genomic DNA from wt/wt, chm³⁵/chm³⁵ and chm³⁵/wt individuals. wt, wild type.