Fig. 3

Subcellular localization of overexpressed PS-1 in COS-7 cells

COS-7 cells were transfected with the PS-1 cDNA and co-stained with antibody BOS4627 (A, PS-1) and a monoclonal antibody to grp78 (BiP), labeling the ER (B, ER). The majority of PS-1 staining was observed within the ER as indicated by the overlapping staining of antibody BOS4627 and the antibody to grp78 (BiP). (C and D). COS-7 cells transfected with the PS-1 cDNA were costained with BOS4627 (C, PS-1) and a monoclonal antibody to p58 (D, Golgi) which is located within the Golgi. Overlapping expression of p58 and PS-1 is observed to some extend within the Golgi. Note that the photograph was taken by focusing on the Golgi. The predominant ER staining with antibody BOS4627 is out of focus. (E and F) Colocalization of PS-1 and βAPP. COS-7 cells were double transfected the PS-1 cDNA and the βAPP cDNA CMV695 (38) and stained with BOS4627 (E, PS-1) and the monoclonal antibody 5A3/1G7 to βAPP (F, βAPP). Note the overlapping staining of PS-1 and βAPP within the Golgi. The photograph focuses on the Golgi, the predominant ER staining of antibody BOS4627 is out of focus.