Fig. 5. Defects in the brain NB pattern in vnd loss-of-function and gain-of-function embryos at stage 11, as revealed by marker genes specific for NB subsets. (A-X) Head flat preparations antibody labeled against Engrailed [En; En-lacZ (E,F,M,N) or En-protein (A-D,Q,R,W,X)] and Empty spiracles (Ems; A-D,Q,R) or Ladybird early (Lbe; E,F) or Eyeless (Ey; M,N,W,X), only Ey (O;P), Lbe (G,H,S,T) and Dachshund (Dac; I-L,U,V) in wild type (wt), vnd mutant (vnd-) and sca-vnd embryos as indicated; ventral views (anterior is upwards). (B,D,F,H,J,L,N,P,R,T,V,X) Higher magnifications at the level of NBs deriving from neuroectodermal regions (NE) framed in A,C,E,G,I,K,M,O,Q,S,U,W. (A,B) Ems is expressed in dorsal NBs in the PC (Ppd2,5,8; the latter two co-express En), DC (Dd3,6,8) and TC (Td6), and in the ventral Pcv5 and Dv3. (C) In vnd embryos, Ems is derepressed in the ventral trito-/deutocerebral NE and (D) in residual ventral/intermediate NBs (indicated with green inscriptions). Dorsal NBs are all identifiable; the ventral Pcv5 is missing. (E) In wild type, Lbe is downregulated in the pNE, (F) confined to the dorsal Td4 and Dd7, and to the ventral Pcv8 and Ppv3. (G) In vnd-, the Lbe domain in the TC and DC is ventrally slightly enlarged. (H) Conversely, Pcv8 and Ppv3 are missing. (I,J) In heterozygotes, Dac is found in about 10 dorsal and three ventral NBs (border indicated by the broken white line in J). Black arrow in I indicates Dac-positive Tv2, red arrow indicates an adjacent Dac cell in the MD. Blue midline staining in I indicates blue balancer. (K,L) In vnd-Dac is ectopically expressed in part of the ventral protocerebral pNE (black arrowhead in K) and approximately four descending NBs (black asterisks in L). Dac expression is absent in position of Tv2, and reduced in the MD. (M,N) Ey-positive NBs are indicated in the TC, DC and PC of wild type. (O,P) In vnd-, Ey is missing at positions of ventral (Dv6, Dv7, Pcv6) and intermediate (Td1, Td2) NBs, but is found in all dorsal NBs (e.g. Dd4 and Pcd2). There is faint ectopic Ey in the ventral intercalary NE (encircled by broken black line in P; the corresponding area is encircled in N). Similarly, ectopic Ey is expressed in ventral NE of the mandibular (MD), maxillary, (MX) and labial (LA) segments (O). (Q) In sca-vnd, Ems is largely repressed in the dorsal pNE of the TC, DC and PC, but not in the ventral pNE. In addition, En is absent from the en hs (corresponding region encircled with a broken line), and diminished in the en antennal stripe (as). (R) The ventral Pcv5 and Dv3 express Ems. The dorsal Dd5 lack En; Ppd5 and Ppd8 lack En and Ems. (S) Lbe is absent in the TC and DC but expanded in the PC. (T) Ppv3 and Pcv8, close to the border of the dorsal PC, express Lbe the strongest; additionally, about five dorsal NBs express ectopic Lbe (white arrowheads). (U) Dac is repressed in the ocular pNE and (V) in dorsal protocerebral NBs, but retained in ventral NBs (Pcv7,9). (W) Ey is repressed in the dorsal pNE of the DC and PC, and is absent in the TC, MD, MX and LA. (X) Ey expression is lacking in dorsal, but retained in most ventral, NBs in the PC and DC. CL, clypeolabrum; FG, foregut; OA, optic lobe anlagen.