FIGURE 3.

G-actin binds to CEACAM1-S peptide in POPS liposome coated glass beads in a Ca²⁺-specific manner. A, POPS liposome-coated 4.5-μm glass beads ± N-acyl-MUA-wild-type peptide ± rhodamine G-actin (or ± G-actin and ± anti-G-actin antibody) ± 1 mm Ca²⁺ in PBS plus 1% BSA were analyzed by FACS (see right panel for details). Significant actin binding is only seen for the fully reconstituted system. B, same experiment as in A except POPC liposome-coated glass beads were used. There was no significant actin binding even for the fully reconstituted system.