Figure 1

Model of the SH4-U domain and, the open and closed full-length Lck conformations. (A) The model of the SH4-U domain (residues 2 to 63) used in this study. The region responsible for coordinating a Zn²⁺ ion is magnified (left). Residues forming the anionic patch in our model are shown as red sticks and labelled. PIP lipid binding cationic residues (R39, R45), as suggested in this study, are shown as blue sticks are located on the opposite side of the anionic patch (middle). The electrostatic profile of the anionic patch (right) shown was calculated in the ± 5 kT/e range and at pH 7.0 using the PDB2PQR³⁸ and APBS³⁹ tools. Electronegative and electropositive regions are indicated by red and blue intensities respectively. (B) The model of the open Lck-FL conformation and (C) the closed Lck-FL conformation used in this study. (D) Isolated SH2, SH3 and kinase domains aligned to the closed state of Hck (PDB:5H0B)³⁴.