Fig. 1. Effect of sense organ specificity on olfactory lobe patterning. The olfactory neurons in wild type and mutants were traced using the SG18.1-Gal4;UAS-GFP strain (green). (A-C) Wild-type antennal lobes; arrowheads mark entry of the antennal nerve and arrows indicate the inter-antennal commissure. (A) Adult lobe. (B) 60 hour APF lobe stained with anti-Fas II. (C) 48 hour APF lobe at the same magnification as (B) showing several well formed glomeruli (*). (D) Adult SG18.1 UAS GFP; ato1/Df(3R)p13 lobes at the same magnification as A. Antennal nerves enter the lobe (arrowheads) but no glomeruli can be discerned. The expected position of the inter-antennal commissure is indicated by (?). (E) 60 hour APF mutant lobe stained with anti-FasII; no glomeruli can be distinguished (compare with B, at the same magnification). (F) 48 hour APF SG18.1 UAS GFP; ato1/Df(3R)p13 lobe. Most afferents are stalled immediately upon entry of the antennal nerve (arrowhead); only a few invade the lobe (arrow). (G-I) Adult wild-type (G) and ato– mutant (H,I) lobes stained with anti-Dachshund (blue in G,H) and anti-Repo (red in G,I). Dorsal (D) and lateral (L) clusters of interneurons are demarcated with dotted lines in G,H. Arrows in G,I indicate glial cells at the lobe periphery. (J) Adult SG18.1-Gal4 UAS GFP/+ (K) and lz3; SG18.1-Gal4 UAS GFP/+ lobes. Well-formed glomeruli are indicated by *, # and o.; white dots indicate glomeruli in the wild type that are poorly innervated in the mutant. (L) 60 hours APF lobe stained with anti-FasII shows presence of several well-developed glomeruli. Scale bars: 25 µm in A,B; 20 µm in K. G-L are at the same magnification.
