FIG. 5.

Mutation of basic/polar residues N terminal to the core LXXLL motif of TRAP220 RBD-2 disrupts ligand-dependent binding of TR as determined by SPR. The sensorgram measures the real-time binding of hTRβ to GST-RBD-2 or GST-RBD-2/mt107 (Fig. 4B) immobilized on the surface of a sensor chip in the presence or absence of T3 as indicated. The arrows indicate the start and the end of a constant-flow injection of the analyte His₁₀-hTRβ over the chip surface. After the 10-min injection was finished, the analyte was replaced by running buffer (HBS-EP [see Materials and Methods]). RU, resonance units.