Phosphoinositide-3-Kinase Interacting Protein 1 (PIK3IP1)

PIK3IP1 that shares homology with the p85 regulatory PI3K subunit.PIK3IP1 directly binds to the p110 catalytic subunit and modulates PI3K activity. PIK3IP1 is a new type of PI3K regulator.

Class Ia Phosphatidylinositol-3-kinases (PI3K) are lipid kinases that generate pro-growth and survival signals in cells. They are heterodimers composed of a regulatory subunit (p85) and a catalytic subunit (p110) . When cells are exposed to growth factors or other stimuli, the p85/p110 complex is recruited to tyrosine-phosphorylated proteins resulting in catalytic activation of the PI3K heterodimer. Kringles are triple looped amino acid motifs that mediate protein-protein interactions. Only a few proteins such as hepatocyte growth factor (HGF) possess kringle domains.