Figure 7.

Fluorescent studies of PS-2 expression in HeLa cells using GFP as a reporter. (A) Fluorescent and phase contrast images of living HeLa cells transfected with pGFP–PS-2, showing the GFP– PS-2 fusion protein is localized to the ER. A presumably untransfected cell is indicated by the arrowhead. (B) HeLa cells were transfected with either GFP alone (top row), GFP fused with wild-type PS-2 (second row), or GFP fused with the AD PS-2(N141I) mutant (bottom row). The fluorescent images of cells expressing GFP proteins on the same area of the gridded coverslip were captured 17 and 65 h after transfection. Please note, the number of fluorescing cells 65 h after transfection increases in cells expressing GFP alone, whereas cells expressing the two GFP–PS-2 fusion constructs show a dramatic decrease in fluorescence.