Figure 4
From: Phosphotyrosine recognition domains: the typical, the atypical and the versatile
Diversity in ligand recognition in the PTB domain family . PTB domains are shown in ribbon representations, with α-helices in green, and β-strands in orange. Bound peptides are drawn as gray sticks. (A) The PTB domain of IRS-1 bound to a pTyr-containing peptide derived from interleukin 4, containing an NPApY sequence (PDB ID: 1IRS) [105]. The two arginine residues, Arg212 and Arg227 (coloured blue), provide electrostatic contacts with pTyr at position 0 (coloured yellow). (B) The Numb PTB domain bound to an NAK-derived peptide (PDB ID: 1DDM) [111]. The peptide contains an NMSF sequence, but not a tyrosine. Phe149 and Phe195 (coloured magenta) of the PTB domain are essential for peptide binding. (C) The tensin2 PTB domain bound to a peptide derived from DLC-1 (PDB ID: 2LOZ) [112]. The peptide, which does not contain an NXX[Y/F] motif, binds to a novel site on the PTB domain that involves the α1 helix.