Volume 8 issue 3 March 2007
Polarized transport of Alzheimer Amyloid Precursor Protein is mediated by
adaptor complex AP-1B
A Icking, M Amaddii, M Ruonala, S Höning and R Tikkanen

Figure 1. Ectopic expression of µ1B in LLC-PK1 cells results in partial basolateral targeting of WT-GFP-APP but not of the Y653A mutant. Distribution of GFP-APP-WT and Y653A mutant to the apical and basolateral cell surface was studied in filter-grown, polarized LLC-PK1 cells by confocal immunofluorescence microscopy. Polarized LLC-PK1 cells expressing GFP-APP alone or together with µ1B-HA were surface-labeled from both apical and basolateral side with GFP-antibodies and fluorochrome-labeled secondary antibodies in order to visualize only the cell surface associated APP-GFP. In the absence of µ1B, both WT (uppermost panel) and Y653A mutant (third panel) GFP-APP are localized at the apical surface. Expression of µ1B-HA results in localization of the WT (Second panel) but not of the Y653A mutant (lowermost panel) to basolateral surface.

Figure 1(.jpg)