Fig. 6: Delta transport from late endosomes to recycling endosomes.
From: Intracellular trafficking of Notch orchestrates temporal dynamics of Notch activity in the fly brain
a, b Dl aggregation (magenta or white) upon rab4 RNAi (optix-Gal4, green in a, blue in b) at 25 °C. Lsc, blue (a) and Rab7, green (b). Dl colocalizes with Rab7 (b). The white dotted box is magnified. The colocalization of Dl with Rab7 is quantified (p = 0.016 (*p < 0.05), two-sided t test). c Loss of Dl expression (arrows) by rab4 RNAi (optix-Gal4, green) at 30 °C at the wavefront (Lsc, blue). The white dotted boxes are enlarged showing the decrease of Dl in the mutant area (yellow) compared with the control area (white). Signals in the magenta dotted box are plotted in the right panel. The magenta arrow indicates the orientation along the x-axis. d, e Dl is upregulated in vha68-2 mutant clones (arrows) visualized by the absence of GFP (green in d, blue in e) at the wavefront (Lsc, blue in a). Ectopic Dl is accumulated in Rab7-positive structures (green in e). f Control distributions of N (magenta), Dl-GFP (green), and Lsc (blue). g–j vha68-2 RNAi under the control of optix-Gal4. Distribution of ectopic N puncta (magenta in g–j), Dl-GFP (green in g, h), Dl (magenta in i), Rab7 (blue in h), and Rab4-GFP (green in i, j) is compared behind the wavefront (Lsc, blue in g, i, j). k, l rab4 vha68-2 double RNAi under the control of optix-Gal4 (GFP, green in k). Dl (magenta), Rab7 (green in l), and Lsc (blue in k). The yellow and white dotted boxes in RNAi and control areas, respectively, are magnified in the right panels. Asterisks indicate the optix-Gal4-positive areas outlined by white lines. m Dl intensity quantification in different RNAi conditions (p values are indicated inside the panel, *p < 0.05, ***p < 0.001, two-sided t test). n Quantification of the colocalization between Dl and Rab7 (p = 0.041 (*p < 0.05), two-sided t test). b, m, n Numbers of quantified areas are indicated. Cross, mean; center line, median; box limits, upper and lower quartiles; whiskers, 1.5× interquartile range in the box plots. o Putative intracellular mechanisms that degrade N and recycle Dl. Scale bars, 20 μm.
