Knockdown of tfap2a/c impairs early placode development. A–G, Expression of early placodal markers in control embryos and tfap2a/c morphants. Expression of pitx3 at 12.5 hpf marks pituitary/olfactory/lens precursors (A); cxcr4b marks the olfactory pit at 30 hpf (B); foxe3 marks the lens at 30 hpf (C); neuroD marks the trigeminal (tg) and anterior lateral line (al) at 14 hpf (D); pax8 at 10 hpf (E) and pax2a at 12 hpf (F) mark otic/epibranchial precursors; phox2a marks epibranchial ganglia (eg) at 30 hpf (G). H–J, Expression of competence factors foxi1 (H) and gata3 (I), and PPE marker dlx3b (J), at 8.5 hpf in control embryos and tfap2a/c morphants. K and L, Expression of tfap2a (K) and tfap2c (L) at 8.5 hpf in control embryos and tfap2a-/- (lockjaw) mutants. M, otic vesicle at 30 hpf in a control embryo, tfap2a/c morphant, and embryos injected with sub-effective doses (0.5 ng) of foxi1-MO, dlx3b-MO or both foxi1-MO and dlx3b-MO. Sub-effective doses of these MO have little or no effect by themselves, but when combined have synergistic effects that phenocopy the tfap2a/c morphant. Images show dorsal views with anterior up (A, D–F), lateral views with anterior to the left (B, C, G, M) or lateral views with dorsal to the right (H–L).