Fig. 2. Anatomical contact between the Bolwig nerve and the lateral neurons in wild type embryo. (A) Whole-mount of a stage-17 w; UAS-lacZ; gal1118 embryo stained with a monoclonal anti-ß-gal antibody to detect the LNs (see Materials and Methods). Broken line indicates the limit between different focal planes. Neurites extending from the labeled cells were seen in 10 out of 17 hemispheres. (B-E) Whole-mount of a stage-17 w; UAS-lacZ; gal1118 embryo double-stained with a polyclonal anti-ß-gal antibody and the anti-chaoptin antibody to reveal the visual system. We also found embryos with only the BO/BN labeled and no detectable gal1118 expression in the LNs (data not shown). This is consistent with the start of gal1118 expression at the beginning of stage 17 that we observed with gal1118-driven GFP in live embryos (not shown). (B) The two Bolwig organs are visible near the oral armature and their projections run around the CNS towards their targets. (C-E) detail of the contact zone (white box in B) from the same embryo at higher magnification. [C,D (green)] Anti-chaoptin staining of the BN termination. [D (red), E] Anti-ß-gal staining of the LNs and their projections. The BN ending appeared to contact the smaller one of the two main neuritic branches, which presumably represents an early stage of development of the dendritic arborization illustrated in Fig. 1. BN, Bolwig nerve; BOs, Bolwig organs; DA, dendritic arborization of LNs; DP, dorsal projections of LNs; LNs, lateral neurons. Arrowheads indicate the contact zone. Scale bars: 10 µm.
