FIGURE 5.

Cells expressing cr-u-PAR resurface recently unoccupied receptor faster than wt u-PAR-expressing cells. wt u-PAR (■) and cr-u-PAR (Δ)-expressing cells were incubated with pre-assembled tcu-PA·PAI-1 complexes at 4 °C. Cells were washed and incubated at 37 °C for the times shown, and the amount of resurfaced unoccupied receptor was assessed via a Pg activation assay. Pg activating activities at each time point are shown relative to samples of cells not incubated with tcu-PA·PAI-1 complex, leaving a full complement of unoccupied u-PAR. As a control, 500 nm RAP was added to each incubation step. Data represent the means ± S.E. of four independent replicates.