Fig. 8. Wg movement is impeded by HSPG-deficient cells. Extracellular Wg staining in discs bearing narrow stripes of clones mutant for sfl (A-B') or dally-dlp (C-D'). All discs are oriented anterior left, dorsal up. The mutant clones are marked by the absence of GFP in the merged images, and outlined by broken lines. The extracellular Wg is reduced not only within these mutant clones, but also in the wild-type cells behind them (pointed by blue arrows). For comparison, the yellow arrows indicate wild-type cells at similar distances from the DV boundary. In each disc, Wg distribution is averaged and plotted (A'',B'',C'',D'') from an area including the narrow clone and the cells behind it and from a control area (boxed in the merged images). The colors of profiles are specified at the bottom of the figure. The left-right axis of the plot profiles corresponds to the ventrodorsal axis of the boxed regions. The drops of GFP intensity indicate the position of the mutant clones.