Figure 9.

Starvation reduces the localization of APP in early endosomes and increases the localization in late endosomes. a, the X-Y confocal images of APP and EEA1 (upper two rows) or Rab7 (lower two rows) in HEK293 cells starved (+) or not (−). APP, EEA1, and Rab7 were immunostained with anti-Myc, anti-EEA1, and anti-Rab7 antibodies, respectively. APP is shown in the 1st panel, EEA1 or Rab7 in the 2nd, and the merge in the 3rd panel. The right panels are a higher magnification view of the white box in the merges. The X-Z and Y-Z reconstruction along the white lines in the X-Y image is shown at the upper and right side of each panel, respectively. Bar for the left three panels, 20 μm; right panels, 5 μm. b, relative level of APP colocalization with EEA1 or Rab7 under normal (−) or starvation (+) conditions. Data are expressed as the mean ± S.E. (n = 20 for EEA1 and Rab7. *, p < 0.05, **, p < 0.01, Student's t test).