Fig. 6

sNPF signaling connects autophagy suppression with presynaptic metaplasticity. Adult brain, 5 days, (a) w1118 and (b) sNPF^c00448 immunostained for sNPF peptide precursor. Scale bar: 50 μm. c Quantification of sNPF peptide precursor within the central brain region normalized to control flies. (n = 9–11 independent brains; ***p < 0.001; Mann–Whitney U-test). Adult brain, 5 days, (d) w1118 and (e) sNPF^c00448 flies, immunostained for BRP^Nc82. Scale bar: 50 μm. f Quantification of BRP^Nc82 within the central brain region normalized to control flies (n = 7–8 independent brains; *p < 0.05; Mann–Whitney U-test). Adult brain, 5 days, (g) +/snpfr-RNAi and (h) ok107/snpfr-RNAi flies, immunostained for BRP^Nc82. Scale bar: 50 μm. i Quantification of BRP^Nc82 within the central brain region normalized to control flies (n = 13–15 independent brains; ***p < 0.001; Mann–Whitney U-test). Electron micrograph showing presynaptic specializations at PN-to-KC synapses in Calyx of (j) +/snpfr-RNAi and (k) ok107/snpfr-RNAi animals. Scale bar: 100 nm. l Quantification representing the average T-bar size in +/snpfr-RNAi and ok107/snpfr-RNAi animals (n = 206 electron micrographs across eight independent animals, with at least 20 T-bars per animal; ***p < 0.001; Mann–Whitney U-test). In the box and whisker plots, the middle line of a box represents the median (50th percentile) and the terminal lines of a box represent the 25th and 75th percentile. The whiskers represent the lowest and the highest value