Fig. 4. Neur induces Ser endocytosis. Details of wing pouches are shown; anterior is towards the left, dorsal is upwards and the DV boundary is at the bottom of each panel. Scale bar: 20 µm. (A,B) dpp-Gal4; UAS-Ser with co-expression of UAS-GFP (A) or UAS-EGFPneur (B). GFP (green) marks the domain of overexpression and Ser (red) is shown separately in A' and B'. Neur causes loss of pericellular staining and an increase in intracellular aggregates in B. (C) Effects of mosaic expression of UAS-EGFPneur on endogenous Ser (red, C'). In cells expressing EGFPneur (green), apical Ser staining is lost. The detection sensitivity for Ser is increased in C compared with A,B to image endogenous Ser levels. (D,E) Green (EGFPneur) channels of C,B, respectively. EGFPneur is cortical with little punctate accumulation when no DSL protein is co-overexpressed (D); when Ser is co-overexpressed there is additional accumulation into punctate structures, which also contain Ser (yellow dots in B). All images are projections of the apical-most 1.5-2 µm of the wing epithelium.