Table 1. Synthetic peptides representing the carboxyl terminus of bovine rhodopsin

WT, amino acid residues 323-348 of wild-type, bovine rhodopsin; 4P, same sequence as the WT peptide phosphorylated on residues equivalent to Ser-338, Thr-340, Thr-342 and Ser-343; 2P, same sequence as the WT peptide phosphorylated on residues equivalent to Thr-340, Thr-342; 7E, contains glutamic acids substituted for Ser-334, Thr-335, Thr-336, Ser-338, Thr-340, Thr-342 and Ser-343 to provide negative charges in place of phosphorylated residues, testing whether the negative charge is sufficient for arrestin binding; Scr, contains the same amino acid composition as the WT peptide but in a random order. Residues in parentheses with a trailing "p" represent phosphorylated residues.

Name                  Sequence
----   --------------------------------------
WT     CGKNPLGDDEASTTVSKTETSQVAPA

4P     CGKNPLGDDEASTTV(Sp)K(Tp)E(Tp)(Sp)QVAPA

2P     CGKNPLGDDEASTTVSK(Tp)E(Tp)SQVAPA

7E     CGKNPLGDDEAEEEVEKEEEEQVAPA

Scr    CTKDPGATEAKSEGLQTDSPVAVTSN