Fig. 2. L(1)sc is expressed in medial edge of the NE and can induce medulla NB differentiation. (A-F') L(1)sc is expressed in the medial edge of NE cells. Early (A,B), mid (C,D) and late (E,F) stages are shown. (A,C,E) Lateral view. Expression of L(1)sc (green), Dpn (magenta) and Dac (white) are shown. Broken white line in A indicates the border between optic lobe and central brain. (B,D,F) Horizontal section. Expression of L(1)sc (green), Dpn (magenta) and tkv-lacZ (blue) are shown. White arrowheads show cells expressing L(1)sc. (B',D',F') L(1)sc expression in B,D,F. (G) Schematics of the horizontal section as in Fig. 1C. L(1)sc-expressing cells (green) and `proneural wave' (green arrow) are shown. (H-M) Uniform and premature NB differentiation associated with ectopic l(1)sc expression driven by NP6099 Gal4. Early (H,K), mid (I,L) and late (J,M) stages are shown. NBs are marked by Dpn (magenta) and neurons by Elav (blue). Broken white lines indicate the border between optic lobe and central brain.