Fig. 8

Spatial expression of the executioner caspases casp3a, casp3b, casp6a, casp7 and casp21 at 24, 48, 72 and 96 hpf.

Lateral views of whole embryos stained for casp3a (A-D), casp3b (E-H), casp6a (I-L), casp7 (M-P), and casp21 (Q-T) by ISH. Casp3a is expressed in the olfactory placodes (op), diencephalon (di), midbrain (mb) and hindbrain (hb) at 24 hpf (A). Expression remains high in the nervous system at 48, 72 and 96 hpf and is strongly detected in the olfactory bulb (ob), retina (r), and optic tectum (ot) (B-D). Casp3a becomes strongly expressed in the intestinal bulb and liver at 96 hpf (D). Casp3b expression is not detected at 24 hpf (E) but becomes visible at 48 and 72 hpf, notably in the pharyngeal arches (pa), muscles (ms) and intestinal bulb (ib) (F, G). Expression becomes restricted to the pharyngeal arches and intestinal bulb at 96 hpf (H). Casp6a expression is mostly detected in the lens (ln), gut (g) proctodeum (pr) and epidermis (ep) at 24 hpf (I). It becomes restricted to the pharyngeal arches at 48 hpf (J), and is strongly detected in the pharyngeal arches, intestinal bulb and liver (lv) at 72 and 96 hpf (K, L). Casp7 expression appears restricted to the lens at 48 and 72 hpf (N, O). It expands to the intestinal bulb at 96 hpf (P). Casp21 expression is not visible at 24 hpf (Q) but is detected in the primary head sinus (phs) at 48 hpf (R). It is maintained in the primary head sinus and is also observed in the primordial hindbrain channel (phbc) and the muscles at 72 hpf (S). Casp21 expression becomes visible in the nervous system, pharyngeal arches and intestinal bulb at 96 hpf (T). Scale bar: 200 μm.