Figure 1.

Structure of the tau protein kinase GSK3β (Protein Data Bank ID (PDB) 3PUP). In the first, largest, image the two lobes can be seen in cartoon representation, and in sticks the residues that form the ATP cavity. In the top and bottom zoom images all the amino acid residues involved on the ATP binding site are shown. Residues in red represent the glycine-rich region (GRR), in blue the hydrophobic pocket (HP), in yellow the adenine region (AR), in lilac the sugar pocket (SP), and finally, in orange the phosphate binding pocket (PBP). Letters and numbers correspond to their position in the amino acid sequence and the PDB file numbering.