Fig 5.

PN-1 binding to HUVECs at 37°C. (A) Whole-cell lysates and cell fractions were obtained after a 2-h incubation of PN-1 variants with HUVECs. Mb, membrane; Cyto, cytosolic. Samples were analyzed as described for Fig. 4, and no signal corresponding to PN-1 was detected in the cytosolic fractions. (B) Whole-cell lysates prepared from HUVECs incubated in the presence or not of heparin (Hep) added at the same time (WT Hep) or 2 h after (WT then Hep), WT PN-1, or of RAP were analyzed as described above. Results are shown in representative blots from at least 3 independent experiments (A and B) or expressed as the mean intensity (PN-1/GAPDH ratio) relative to control WT binding, determined for each immunoblot (C). *, P < 0.05; ***, P < 0.0001, versus WT.