Fig. 8

AGE ligand induces membrane protein complex formation

RAW 264.7 cell membrane preparations were incubated with ¹²⁵I-FFI-BSA at 37°C for the indicated time. After adding SDS-PAGE buffer containing 5% β-mercaptoethanol, the samples were boiled and electrophoresed through a 12% gel. The proteins were visualized by autoradiography. ¹²⁵I-FFI-BSA was incubated without cell membrane (Lane a), with cell membrane for 1, 3, and 6 hr, respectively (Lanes b–d), in the presence of 50-fold unlabeled FFI-BSA for 6 hr (Lane e), in the presence of membrane extracts and hydroxylamine (100 mM, 6 hr) (Lane f). Unmodified ¹²⁵I-BSA alone (Lane g) or with cell membrane used as controls (6 hr) (Lane h). Very high molecular weight complex formation is indicated on top of gel by arrow. Data are representative of six independent experiments.