Fig. 1. WLE3 mediates apical localization of wg transcripts. (A) Fluorescent deletion constructs of wg 3'UTR RNA were injected into D. melanogaster embryos. Localization efficiency was categorized based on the apical:basal ratio of fluorescent RNA signal as strong (++, ratio 1.5), weak (+, 1.5>ratio1.0) or inactive (-, ratio <1.0). The typical activity of each construct is indicated at the right (^* constructs typically inactive but occasionally localized). WLE3 spans nucleotides 518-570, WLE1 57-183, and WLE2 661-776. (B-D) Representative images of embryos injected with fluorescently labelled full-length wg 3'UTR (B), deleted for WLE3 (C) or WLE3 dimer (D). (E-G) Confocal images of stage 11 patched-GAL4::UAS-lacZ embryos containing different regions of the wg 3'UTR fused to lacZ ORF: WLE1-WLE2 (E); WLE1-WLE2-WLE3 (F); WLE3 (G). lacZ reporter transcripts (green) were detected by FISH. Nuclei are red and membranes blue. Scale bars: 10 µm.