label: phosphatidylinositol 3-kinase regulator activity
label_lc: phosphatidylinositol 3-kinase regulator activity
description: "Modulates the activity of a phosphatidylinositol 3-kinase (PI3K). Regulatory subunits can link a PI3K catalytic subunit to upstream signaling events and help position the catalytic subunits close to their lipid substrates."