Fig. 7. Effects of fgf3 knockdown on inner ear development. Dorsolateral view (anterior towards the left) of otic vesicles in embryos injected with fgf3-MO. (A-C) In situ hybridization of pax5 at 24 h in injected wild-type (A) and injected val/val (B,C) embryos. Expression levels are greatly reduced in half to two-thirds of embryos (see text for details). (D,E) Expression of zp23 at 24 h in injected wild-type (D) and injected val/val (E) embryos. Expression is detected throughout the medial wall of the otic vesicle, including cells adjacent to r4. (F) In situ hybridization of nkx5.1 at 24 h in an injected val/val embryo. No expression is detected in the otic vesicle. (G-I) Anti-Pax2 staining at 30 h in injected wild-type (G) and injected val/val (H,I) embryos. The number of hair cells is reduced relative to uninjected controls, and the majority (19/25) of val/val embryos do not produce ectopic hair cells. fgf3-depleted val/val embryos with extremely small otic vesicles (I) produced anterior hair cells only. Relative positions of rhombomeres are indicated. Scale bar: 70 µm in A-C,F; 50 µm in D,E; 30 µm in G-I.