Fig. 2.

Decreased endocytosis and neuropeptide release at distal type II boutons. (A) Quantification of FM4-64 uptake in the proximal region (i.e. within the 7 to 8 boutons closest to the axon) and the distal region (within the 7 to 8 boutons from the axon terminus) on m2. N is the number of regions, which were from 12 animals. F, fluorescence; a.u., arbitrary units. (B) Pseudo-color images of Dilp2–GFP in distal (top) and proximal (bottom) type II boutons on m2 before (Con) and after stimulation by depolarization for 3 min (Stim). Scale bar: 2 µm. (C) Quantification of percentage release in proximal and distal boutons calculated as loss of GFP fluorescence. Total number of boutons examined in 4 animals is indicated for each group. *P<0.05, Student's t-test.