Figure 1.

Crystal structures presenting the rhodopsin/arrestin-1 finger loop binding interface. A, crystal structure of a fusion protein of constitutively active, thermostable human opsin (orange, substitutions: E3.28Q/M6.40Y and N2C/N282C) with preactivated mouse visual arrestin (purple). B, crystal structure of light-activated native bovine rhodopsin (orange) and ArrFL-1 (purple), an 11-mer peptide derived from the arrestin-1 finger loop (⁶⁷YGQEDIDVMGL⁷⁷). PDB IDs are 4ZWJ and 4PXF for A and B, respectively. Parts of TM6 were omitted for clarity (asterisk).