Figure 1.

Structural Features of GRP1-PH

(A) The three binding loops, β1/β2 (black), β3/β4 (green), and β6/β7 (blue), and their positions relative to the I(1,3,4,5)P₄ head group.

(B) The geometry of the I(1,3,4,5)P₄ binding site, with the key amino acid residues referred to in the text shown as stick representations in pink.

(C) The initial setup for the MD simulations, with the centers of the phosphate groups shown as gray spheres and the lipid bilayer depicted as a translucent white surface. Water molecules and ions are omitted for clarity. In all cases, the protein is shown as a ribbon diagram, and the I(1,3,4,5)P₄ head group is shown as a stick model.