Figure 1. Sequencing and in situ hybridization mapping locate the Y-linked PEV reporters in the telomeric transposon arrays of Ys.

(a) Alignment of reporter insertion flanking sequences to a consensus sequence of telomeric retro-transposon TART-B2. The 1 Kb region in the 3′-UTR harboring the insertion sites is magnified. The effective sequence read length for each reporter line is represented by the red line aligned to the region. The red dot at the end of each red line indicates the 5′ end of the reporter. The reporter flanking sequence of line 5m298 starts in the 3′ end of a TART-B2 element and extends upstream to a neighboring HeT-A element, suggesting insertion into a partial fragment of TART. (b) In situ hybridization images of the metaphase chromosomes from third instar larval brain squashes. Only the Y chromosome of the representative metaphase spread is shown. DAPI staining is pseudo-colored in blue and the hybridization signal is in red. (C: centromere, Y^L: long arm, Y^S: short arm).