Figure 3

The structural organization of p110-α enzyme. The catalytic subunit (p110-α) of PI3Ks possesses a central region flanked by the N- and C-terminus of varying lengths with distinctive modular organization. The N-terminus of p110-α enzyme harbors the p85-binding domain (PI3K-ABD) and the Ras-binding domain (PI3K-RBD) which mediates interaction with the regulatory p85 and the Ras-GTPases respectively. The central region is composed of the C2 PI3K-type and PIK helical domains, whereas the C-terminus houses the enzymatic apparatus (PI3K/PI4K kinase domain). Common cancer-associated mutations within each domain of the enzyme is indicated.