FIGURE 1.

Locations of fluorophore attachment. Model of arrestin derived from the crystal structure (12). The N-domain is colored blue; the C-domain is colored green, and the C-terminal tail is colored orange. The residues, which were individually mutated to cysteine and then reacted with the IANBD fluorophore, are indicated. Note that Ala-366 is located in a long flexible loop (dashed) not visible in the crystal structure. The receptor-binding interface of arrestin is oriented toward the top in this figure.