Figure 3.
Long-range interactions between sd and the BX-C depend on sequence homology at Fab-7 and on the presence of PCL protein. (A) Two-color FISH in whole-mount female embryos. Examples of merged images of Dapi labeling (blue), the sd locus (green) and the BX-C (red) are shown. Projection of two Z-axis slices is shown. Embryo genotypes are indicated above each panel. Arrows indicate cases of colocalization between sd and the BX-C. (B) Single slices of individual nuclei show characteristic examples of data obtained in different lines. Dapi staining, the sd locus, the BX-C locus, and the merge of the three channels are shown. The genotypes and the presence of the endogenous or the transgenic Fab-7 copies are indicated. (C) Quantification of the percentage of colocalization of the two loci in stage 9-11 female embryos from different lines. The genotypes and the embryonic position of the analyzed nuclei are indicated below each bar. Error bars represent the standard deviation. At least 50 nuclei per embryo from four to sixembryos were analyzed in each experiment. (D) Same quantification as C, but from an independent experiment comparing female Fab-X embryos with mutant Fab-X; Pcl10 embryos analyzed at stage 13-15 of development. (E) Quantification of long-distance Fab-7 pairing in third instar larval wing imaginal discs, measured as percentage of colocalization of the two loci in the different lines.