HRP-labeled debris are presynaptically derived.

<p>Composite confocal images correspond to 6 h APF pupae. <b>A-C</b>, The anti-HRP labeled puncta (grey, blue in the merge) colocalized with anti-FASII (red) (arrowheads). <b>D-F</b>, <i>UAS-mCD8-GFP</i> (green) was driven in motor neurons with <i>OK6-GAL4</i>. Most of the anti-HRP labeled debris (red) were GFP-positive (arrowheads). <b>G-I</b>, The anti-HRP labeled puncta (grey, blue in the merge) colocalized with CSP (red) (arrowheads). Note the pink color in the merge marked by arrowheads in C and I. <b>J-L</b>, The HRP-positive puncta (grey, blue in the merge) did not co-localize with D-GluRIIC (red), (arrow in J and L). The inset in L shows a high magnification (2×). Bars, 20 µm. Genotypes: (A-C, G-L) <i>MHC-mGFP-Shaker</i>, (D-F) <i>OK6-GAL4/2×UAS-mGFP.</i>