Surface Plasmon Resonance, SPR, analysis of the interaction between merlin and p55. (A) BIAcore comparison of p55 binding with the NF2 protein constructs. Sensograms were obtained from SPR analysis of the interaction between His-p55 and merlin proteins. Recombinant His-p55 was immobilized on the CM5 sensor chip, and 100 nM fusion proteins, MBP-NF2-N and MBP-NF2-C, were injected as analytes. MBP at 100 nM (analyte) was used as a negative control. The sensograms were generated using a 30 μl/min flow rate, and included a 3-min association and a 5-min dissociation section. (B) Sensograms of His-p55 binding with MBP-NF2-N protein. MBP-NF2-N protein (analyte) was injected over the His-p55 protein immobilized onto the CM5 sensor chip at various concentrations ranging from 20–120 nM. Binding reaction was performed at 30 μl/ min flow rate at 25°C. The data were analyzed with the BIAevaluation 3.0 software and the conformation change model gave the best curve fitting yielding a KD value of 3.7 nM.