Fig. 1

Atl-KD in motoneurons increases synaptic pMAD and morphometric parameters A Illustration of the Drosophila larvae body wall preparation, the area that is imaged in the following pictures and the synaptic boutons of the NMJ Cartoon created with BioRender.com. B, C Representative confocal microscopy images (maximum intensity Z-projection) of synaptic boutons immunostained for pMAD B and the quantification of its intensity in larvae expressing Atl-KD or Tkv-CA using the driver C380 B and C or OK6 C: pMAD intensity was normalized to the control pMAD intensity levels (Driver C380 or Ok6, respectively). D, E) Representative confocal microscopy images (maximum intensity Z-projection) of synaptic boutons immunostained for pMAD D and the quantification of its intensity in larvae heterozygous for the wit mutation alone or with Atl-KD using the drivers C380 D and E and OK6 E. pMAD intensity was normalized to the control pMAD intensity levels (C380 or OK6, respectively). pMAD antibody staining is in cyan color. Scale bar of large image: 5 µm, of cropped image: 2 µm. F–G Representative confocal microscopy images (maximum intensity Z-projection) of presynaptic terminals of larvae of the different genotypes labeled with CSP and HRP antibodies staining in green and gray color, respectively. In cropped images, satellite boutons are indicated by white circles. Image intensity and contrast have been increased for visualization purposes. Scale bar 20 µm and 10 µm in the magnified insert. H–I Quantification of synaptic and satellite bouton number of the genotypes in F–G. Each dot represents one larva. Kruskal-Wallis, p-value * < 0,05; ** < 0.01; *** < 0.001. n = 5-9