Fig 5. Driving a flanking P-element promoter with a heterologous enhancer induces non-coding transcription, and if it causes read-through, repression of the eve promoter.

eve-lacZ and non-coding RNA expression in stage 5 embryos from eve pseudo-loci flanked by a 5’ P-element promoter and a neuroectodermal enhancer (NEE, brown square), inserted at the same MiMIC site as in Fig 4, and in the same orientation. The 3 loci (map above each one) differ only in the presence (A, NEE-Pwt) or absence (B, NEE-PΔ and C, NEE-PinvΔ) of homie, and in the orientation of the NEE, P-pro cassette (NEE-P, pointing to the left in A and B, and to the right in C). Positions and orientations of the RNA probes are shown as black and red arrows in the map in A (and in B and C for the probe closest to the P-promoter). Embryos were stained with the probes listed in A, using either black lettering corresponding to black arrows in the map (detecting transcription from right to left), or red lettering corresponding to the red arrow (detecting transcription from left to right).