Fig. 7. Analysis of cell death in ika mutant pectoral fin mesenchyme. (A-C) TUNEL staining on 30 hpf wild-type (WT, A) and ikarus (ika) mutant (B,C) fin level cryosections. Anterior is to the top. No apoptotic cells could be detected in the fin mesenchyme of ika mutants (n=16, B). In one specimen, a few apoptotic cells could be detected in the apical fin ectoderm but not in the fin mesenchyme (C). Arrows indicate fin bud; asterisks indicate the absence of bud formation in ika mutants.