FIGURE 1.

Nuclear export of TonEBP in response to hypotonicity. A, dose dependence. COS7 cells grown on glass coverslips were switched for 30 min to hypotonic media of 210 to 135 mosmol/kg, made by deleting appropriate amounts of NaCl, or kept in isotonic medium (335 mosmol/kg), as indicated. TonEBP was visualized by immunofluorescence. B, time course. Cells were switched to hypotonic medium (135 mosmol/kg) for up to 60 min, as indicated, and TonEBP was visualized as above. C, cells grown on plastic dishes were switched to hypotonic medium for up to 120 min, as indicated, and immunoblotted (IB) for TonEBP and HSC70.