Fig. 5. Expression of cas, Fas2, klu, lbe, pdm1 and unpg at embryonic stages 9, 10 and 11. Semi-schematic presentation of Castor (cas), Fasciclin 2 (Fas2), Klumpfuss (klu), Ladybird early (lbe), POU-domain 1 (pdm1) protein, and unplugged-lacZ (unpg) expression in brain NBs [A,D,G; low () and high (+) expression levels; red lines mark neuromeric boundaries], and within the outer procephalic ectoderm [B,C,E,F,H,I; thick hatching indicates strong (+), thin hatching weak () expression] as indicated at stage 9 (st9, A-C), stage 10 (st10, D-F) and stage 11 (st11, G-I). Engrailed (en) expression domains in the peripheral ectoderm are indicated for comparison. Anterior (a) is towards the top; dorsal (d) is towards the left. AN, MD, MX, antennal, mandibular and maxillary segment, respectively; CL, clypeolabrum; FG, foregut; ML, ventral midline; OA, Bolwig organ/optic lobe anlagen; as, en antennal stripe; hs, en head spot; is, en intercalary stripe.