Fig 4. Brat regulates margin cell-fate specification.

(A) Drawings of a wing imaginal disc and an adult wing. D = dorsal and V = ventral compartments of the wing disc, with the dorsoventral boundary marked in purple. Notch signaling and Cut expression are present at the dorsoventral boundary, which forms the adult wing margin, also marked in purple. Achaete-expressing cells, marked in green, give rise to the sensory bristles at the anterior half of the margin in the adult wing, also marked in green. (B) ap-lacZ expression in an undamaged control disc from a third-instar ap-lacZ/CyO animal. (C-D) ap-lacZ expression in an R24 control (w¹¹¹⁸) disc (C) and an R24 brat¹/+ disc (D). (E-F) NRE-GFP expression in an undamaged control (w¹¹¹⁸) disc (E) and an undamaged brat¹/+ disc (F). (G-J) NRE-GFP expression in an R0 control (w¹¹¹⁸) disc (G), an R24 control (w¹¹¹⁸) disc (H), an R0 brat¹/+ disc (I) and an R24 brat¹/+ disc (J). (K-L) Anti-Ct immunostaining in an undamaged control (w¹¹¹⁸) disc (K) and an undamaged brat¹/+ disc (L). (M-O) Anti-Ct immunostaining in an R72 control (w¹¹¹⁸) disc (M) and an R72 brat¹/+ discs (N-O). Arrowheads point to loss of Ct expression in (O). (P-Q) Anti-Ac immunostaining in an undamaged control (w¹¹¹⁸) disc (P) and an undamaged brat¹/+ disc (Q). (R-S) Anti-Ac immunostaining in an R72 control (w¹¹¹⁸) disc (R) and an R72 brat¹/+ disc (S). Scale bars are 100 μm.