Figure 5. EGFR shows differential localization in filopodia of primary Drosophila neurons.

(A–B) UAS-EGFR^GFP expressed with elav-Gal4 in wild type (A) and EGFR^DN (B) primary Drosophila neurons. False color image displaying a heat map of an EGFR^GFP-expressing growth cone. EGFR^GFP expression in dynamic (A′ and B′) and static filopodia (A″ and B″) is followed over time in wild type (A′ and A″) and EGFR^DN (B′ and B″). A′ and B′ each shows one filopodia growing and one retracting (C). To quantify EGFR^GFP intensity in static vs dynamic filopodia in the absence (control) or presence of EGFR^DN, we calculated the ratio of EGFR^GFP in dynamic minus static filopodia (GFP maximal intensity of each dynamic phase minus the mean of GFP maximal intensity in static filopodia). The difference in EGFR^GFP levels between dynamic filopodia and static filopodia are significantly reduced in the presence of EGFR^DN (control dynamic-static: 0.1046 ± 0.009, n=216; EGFR^DN dynamic-static: 0.0349 ± 0.0121, n=124, p<0.001). Error bars represent SEM. Mann–-Whitney test. ***p<0.001.

DOI: http://dx.doi.org/10.7554/eLife.01699.013

Figure 5—figure supplement 1. Localization of EGFR in cultured neurons.

UAS-EGFR^GFP under control of sca-Gal4 is significantly higher expressed in dynamic filopodia compared to static filopodia in cultured wild-type neurons.

DOI: http://dx.doi.org/10.7554/eLife.01699.014

Figure 5—figure supplement 2. Colocalization of EGFR with Rab11 and Rab5 in the growth cone.

(A–B) Growth cones from primary Drosophila neurons expressing UAS-EGFR^GFP with elav-Gal4. Neurons were inmunostained for the recycling endosomal marker Rab11 (A, B, A‴, B‴ in red), GFP (A′, B′, A‴, B‴ in green) and the early endosomal marker Rab5 (A″, B″, A‴, B‴ in blue). Note that a fraction of EGFR granules colocalises with Rab11 (arrows) or Rab5 (arrowheads). The scale bars in (A) represent 1 µm.

DOI: http://dx.doi.org/10.7554/eLife.01699.015