. "Authored: Akkerman, JW, 2009-09-04"^^ . "Reviewed: Harper, MT, 2009-11-02"^^ . "Reviewed: Poole, AW, 2009-11-02"^^ . "Reviewed: Jones, ML, 2009-11-02"^^ . "Edited: Jupe, S, 2009-11-03"^^ . "Class I Phosphoinositide 3-kinases (PI3Ks) are heterodimeric proteins, each having a catalytic subunit of 110-120 kDa and an associated regulatory subunit. PI3Ks alpha, beta and delta share a common regulatory p85 subunit, PI3K gamma has a p101 regulatory subunit. All the class I PI3Ks are able to phosphorylate PtdIns, PtdIns-4-P, or PtdIns-4,5-P2 (PIP2) on the free 3-position, and have a strong preference for PIP2.They are activated by receptor tyrosine kinases and by Ras and Rho family GTPases."^^ . . . . . . . . . "PI3K alpha, beta, gamma convert PIP2 to PIP3"^^ . "2.7.1.153"^^ . . . . .