Fig. 5. dlx3 and dlx7 affect otic placode formation before the onset of pax2.1 otic expression but after that of pax8. Whole-mount RNA in situ hybridization at 3 somites with (A,F) wild-type, (B,G) dlx7 MO, (C,H) dlx3MO, (D,I) dlx3+7 MO and (E,J) b380 mutant embryos. (A-E) pax8 is expressed in the presumptive otic primordia (ot) and the pronephros (pn) at this stage. Expression of this gene is unaffected by a loss of dlx3 or dlx7 function. (F-J) pax2.1 is expressed in the presumptive otic primordia (ot), pronephros (pn), midbrain-hindbrain boundary (mhb) and optic stalk (not shown) at this stage. Expression is reduced specifically in the otic primordia of (H) dlx3 MO-injected embryos, and is undetectable in (I) embryos injected with dlx3+7 MO and in (J) b380 mutants. All panels show dorsal views with anterior towards the left. Scale bar: 100 µm.