...`jumpstart' of otic specification that is maintained by the Dlx3b-Pax2a pathway. * Author for correspondence (e-mail: monte@uoneuro.uoregon.edu ) 9 7 2004 © 2004. 2004 dlx3b fgf3 fgf8 foxi1 Inner ear Morpholino Otic placode pax8 pax2a sox9a sox9b Zebrafish...

... cells form. Removal of dlx3b, dlx4b and sox9a genes together also blocks ear development, although a few residual cells form an otic epithelium. These cells fail to form if sox9b function is also blocked. Combined loss of Fgf signaling and the three transcription factor genes, dlx3b,dlx4b and sox9a...

... in sox9a , one of two zebrafish orthologs of the human transcription factor SOX9 . A mutation induced by ethyl nitrosourea changed a conserved nucleotide at a splice junction and severely reduced splicing of sox9a transcript. A retrovirus insertion into sox9a disrupted its DNA-binding domain. Inhibiting...