FIGURE 4:

Loss of AP-4 in i³Neurons results in axonal lysosome buildup. Control and AP-4 G4i i³Neurons (42 DIV) stained for LAMP1 (green) and Tau (red). White arrows highlight LAMP1 accumulation in the neurites of AP-4 i³Neurons. Yellow asterisks indicate the LAMP1-positive vesicles in the cell body. Bar, 20 µm. (B) Quantification of axonal LAMP-positive swellings per unit area in AP-4 i³Neurons and Control i³Neurons (42 DIV; mean ± SEM from three independent experiments; >20 areas imaged at random per genotype; *P < 0.05). (C) Representative images of Control and AP-4 G4i i³Neurons (42 DIV) stained for LAMP1 (green) and MAP2 (blue). Arrowheads highlight LAMP1 accumulation in the MAP2-negative neurites (axons) of AP-4 i³Neurons. Bar, 20 µm.