Figure 1. Increased R8 spacing in D-cbl clones is Notch-dependent.
(A) Domain structure of the long and short isoforms of D-Cbl. The relative locations of the non-sense mutation in D-cblK26 and the missense mutations in D-cbl7 are indicated. TKB - tyrosine kinase binding domain; L – Linker; RING - RING E3 ubiquitin ligase; UBA - ubiquitin-associated domain.
(B,B′) Increased spacing between R8 photoreceptor cells in D-cblK26 mutant clones. Anti-Senseless (Sens) labeling is shown in red to mark R8 cells. Anterior is to the left. Absence of GFP marks D-cbl mutant clones outlined by white lines in (B′). White triangles mark the position of the morphogenetic furrow. Genotype: ey-Flp; D-cblK26 FRT80/P[ubi-GFP] FRT80.
(C,C′) Heterozygosity of Notch (N) normalizes R8 spacing in D-cblK26 mutant clones. Mutant clones are outlined by white lines in (C′). White triangles mark the position of the morphogenetic furrow. Genotype: ey-Flp/Df(1)N8; D-cblK26 FRT80/P[ubi-GFP] FRT80. A similar result was obtained with N264-39 (data not shown).
(D,D′) Increased ommatidial spacing in D-cblK26 clones in 42 hours APF pupal eye discs labeled with Elav (marks photoreceptor neurons or R cells) in red. The D-cbl clone is marked by absence of GFP and outlined by a white line in (D′). Genotype as in (B).
(E) Summary of the analysis of R8 spacing. The distances between R8 cells in the MF and posterior to the MF in eye imaginal discs of the indicated genotypes are measured by Axiovision 6 program with the average length per R8 pairs in μM. A total of 100 R8 pairs from 10 different discs were measured for each data point.
(F,F′) argosΔ7 and (G,G′) gap123-9s mutant clones do not affect R8 spacing as determined by Sens labeling in red. Mutant clones are outlined by white lines in (F′,G′). White triangles mark the position of the morphogenetic furrow. Genotypes: ey-Flp; argosΔ7 or gap123-9s FRT80/P[ubi-GFP] FRT80.