Ribbon and molecular surface representation of p110, showing the locations of gain-of-function mutations on the homology model. The domains of p110 are colored as follows: C2 domain, blue; helical domain, green; N-terminal region of the kinase domain, red; C-terminal region of the kinase domain, yellow; and linker region, white. The gain-of-function mutations are represented as red van der Waals (VDW) spheres. Nontransforming mutation sites that are not solvent-exposed are indicated as blue VDW spheres. The magentaVDWspheres mark nontransforming mutation sites that are solventexposed. The activation loop (red) and catalytic loop (green) are also labeled. Image courtesy of Marc Elsliger.