Receptor autophosphorylation requires a lysine at position 1057 to stabilize the gamma phosphate of ATP. The adenosine of ATP interacts with three glycines at residues 1030-1035. The first tyrosine residues to be autophosphorylated are 1185, 1189 and 1190 in the kinase domain. This is followed by 999 in the juxtamembrane domain, 1355 and 1361. These tyrosines fall into the three distinct tyrosine phosphorylation domains of the beta-subunit. In total there are 13 potential tyrosines that may be phosphorylated. The receptor phosphorylates itself in a trans rather than cis manner, where the beta-subunits phosphorylate each other rather than themselves (Tavaré et al. 1998).