FIG. 3.
Frequency of colocalization of Mcp and Fab-7 transgenes. (A) Interactions between Mcp transgenes. For each of the pairwise combinations between three lines bearing the Mcp construct, the histogram shows frequencies of colocalization (one-dot nuclei) for the starting lines (Intact), for the lines after PRE deletion (ΔP), or for the lines after insulator deletion (ΔI). (B) Interactions between Fab-7 transgenes. The histogram shows the frequencies of colocalization for the pairwise combinations between three lines bearing the Fab-7 construct. In both sets of experiments, the frequency of colocalization drops more than 30-fold when the insulator is deleted but is not affected by deletion of the PRE (data not shown). Some combinations were tested in a background with a deletion of the endogenous Fab-7 element (Fab-71), showing that it is not required for the trans interactions. (C) Interaction between Mcp and Fab-7 transgenes. The histograms show the frequencies of colocalization between the F9 and the M31 transgenes before or after deletion of the PRE or insulator segments. Numerical data are available upon request.