Table 1.

Schematic representation of known PDZ ligand binding preferences

Distal C-terminus motif	−2	−1	0
Class I	Ser/Thr	X	Φ
Class II	Φ/Ψ	X	Φ
Class III	Asp/Glu	X	Φ
Class IV	X	Ψ	Asp/Glu

X: any amino acid

Φ: hydrophobic amino acid

Ψ: aromatic amino acid