<p>(<b>A</b>-<b>F</b>) Uninjected and <i>fgf10a</i>-MO injected progeny from fgf3+/-;TgBAC(neurog1-DSRed) crosses were collected at 36 hpf and immunolabeled for Pax2a and DSRed to visualize EB placodes and migrating neuroblasts, respectively. Wild-type (A) and fgf3+/- (B) panels shows <i>neurog1:DSRed</i>+ cells undergoing neurogenesis (magenta) at the dorsal aspect of the mature Pax2a+ EB placodes (green; dotted line). fgf3-/- embryos show a loss of properly formed Pax2a+ EB placodes in the region of the prospective glossopharyngeal and three small vagal ganglia and a concurrent loss of <i>neurog1:DSRed</i>+ cells in this region (C; bracket); however, the facial and large vagal placode/ganglia are still present (arrowheads). Analysis of <i>fgf10a</i>-MO injected wild-type (D) and fgf3+/- (E) embryos reveal ectopic neurogenesis as marked by <i>neurog1:DSRed</i>+ cells ventral to the posterior most aspect of the vagal placode (arrow). <i>fgf3-/-</i>;fgf10-MO embryos show a complete loss Pax2a expression in EB placodes and an absence of neurogenesis, except for a few <i>neurog1:DSRed</i>+ cells near the region of the large vagal ganglia (F; asterisk). Abbreviation: <i>ngn:dsred</i>, TgBAC(neurog1-DSRed); f, facial placode; g, glossopharyngeal placode; v, vagal placodes. Scale bar: 50 µm. </p
