Figure 4.

Hypo-osmotic conditions induce the redistribution of ERGIC 53 to the ER. HeLa cells were grown to 50% confluence on 12-mm glass coverslips. Coverslips were removed from normal medium and placed in 1 ml of hypotonic (210-mOsm) medium for 15 min (B) or 30 min (C). Cells maintained in normal medium are shown in A, and cells incubated in normal medium with 10 μg/ml BFA for 60 min are shown in D. Cells were fixed and processed for immunofluorescence using a mAb against ERGIC 53.