Fig. 4.

Ets1 and cMyb are necessary for activation of Sox10E2 element. (A) Control morpholino (Right; red) has no effect on Sox10E2-driven Cherry (B) (green) compared to nonelectroporated (Left) side. cMyb MO (D) significantly reduces, whereas Ets1 MO (G) abolishes Sox10E2-driven Cherry expression, (E and H, respectively; C, F, and I are merged images of A/B, D/E, and G/H, respectively). White dotted lines indicate the midline. Green/red channels are inverted for consistency. (J–L) Endogenous cMyb, Sox9, and Ets1 expression precedes that of Sox10. At HH6, cMyb is expressed within the neural plate border (J) and confined to dorsal neural folds by HH8 (K and K′, arrowheads). At HH10, cMyb is observed in migrating neural crest (L and section at dotted line, L′ arrows). At HH8, before Sox10 onset, Sox9 (M) and Ets1 (N) are expressed by presumptive CNC in the dorsal neural tube.