Fig. 6. Surface plasmon resonance detects interaction between proximal leg segments. Clathrin constructs were expressed, purified and tested for interactions using a BIAcore Processing Unit. Proximal leg segments, Hubs, or chimeras were immobilized to a CM5 chip. Mobile solutions of clathrin fragments or chimeras were flowed over the surface at pH 6.7 and changes in refractive index monitored. Lower curves represent lower concentrations of mobile species. (A) Immobilized proximal leg segment (5029 RU) interacts with proximal leg segments at 2.5, 5.0, 7.5, 10.0 and 12.5 µM. (B) Immobilized Hub (6144 RU) interacts with Hub at 0.5, 1.0, 1.5, 2.0, 2.5 and 3.0 µM. (C) Immobilized proximal-Ii chimera (5731 RU) interacts with proximal-Ii chimera at 1.0, 2.0, 2.5, 3.0, 4.0 and 5.0 µM. (D) Immobilized distal-Ii chimera (5115 RU) interacts with distal-Ii chimera at 0.25, 0.50, 0.75, 2.5 and 5.0 µM. (E) Immobilized Hub (6144 RU) interacts with distal-Ii chimera at 0.25, 0.50, 0.75, 2.5 and 5.0 µM.