Fig. 6. Expression of cas, Fas2, klu, lbe, pdm1 and unpg at embryonic stage 11. Double staining for expression of En/Inv (lacZ or antibody staining) or svp-lacZ (C,D) and Castor (cas; A,B), Fasciclin 2 (Fas2; C,D), Klumpfuss (klu; E,F), Ladybird early (lbe; G,H), Pou-domain 1 (pdm1; I,J), and unplugged-lacZ (unpg-lacZ; K,L), respectively, as indicated. (A,C,E,G,I,K) Focus is on the outer procephalic ectoderm of flat preparations (dashed line indicates ventral midline); insets show lateral views of wholemounts. (B,D,F,H,J,L) Higher magnifications of regions indicated by frames in A,C,E,G,I,K at the level of deuto- and protocerebral NBs; positively stained NBs are indicated by white labels, negative ones by black labels; NBs in brackets are not in focus. (A) Red arrowhead indicates expression of Cas in the outer ectoderm; dashed red line indicates the boundary between the labral (Lr-P) and ocular part of the protocerebrum (Oc-P). Cas is prominently expressed in most brain NBs (B). (C,D) Fas2 is expressed on the surface of most tritocerebral NBs and a few deutocerebral NBs (D). (E,F) Nuclear Klu expression is detected in almost all brain NBs. (G,H) Lbe is segmentally expressed in the head (arrows). (I,J) Approximately one half of the brain NBs express pdm-1, including most deuto- and tritocerebral, as well as central ocular and part of the labral, NBs. (K,L) unpg-lacZ is strongly expressed in almost all deutocerebral NBs, and in some ocular NBs close to the deutocerebral/ocular border. AN, antennal, segment; CL, clypeolabrum; Lr-Pc, labral part of the protocerebrum; Oc-Pc, ocular part of the protocerebrum; OA, Bolwig organ/optic lobe anlagen; as, en antennal stripe; hs, en head spot; is, en intercalary stripe. Anterior (a) is towards the top; dorsal (d) is towards the left.