Fig. 6. Model that reconciles the opposite phenotypes seen as a result of
dlp overexpression. Wingless can bind to several receptors as it
reaches a target cell. Binding to Dlp would prevent access to the signalling
receptors and favour presentation to a neighbouring cell. By contrast, binding
to the signalling receptors would not only lead to signalling but also to
trapping and degradation, thus preventing subsequent transport.