Phosphatidylinositol 3-kinase (PI3K) is a lipid kinase that phosphorylates phosphatidylinositol and similar compounds, creating second messengers important in growth signaling pathways. PI3K functions as a heterodimer of a regulatory and a catalytic subunit. The protein encoded by this gene is a regulatory component of PI3K. Two transcript variants, one protein coding and the other non-protein coding, have been found for this gene. [provided by RefSeq, Dec 2012],MPPH, MPPH1, P85B, p85, p85-BETA,Apoptosis,Apoptosis_Inhibition of Apoptosis,Apoptosis_Mitochondrial Control of Apoptosis,B Cell Receptor Signaling Pathway,Cell Biology & Developmental Biology,Cell Intrinsic Innate Immunity Signaling Pathway,Cytoskeleton,Cytoskeleton_Actins,Endocrine & Metabolism,Epigenetics & Nuclear Signaling,ErbB-HER Signaling Pathway,ESC Pluripotency and Differentiation,IL-6 Receptor Signaling Pathway,Immunology & Inflammation,Innate Immunity_TLR Signaling,Insulin Receptor Signaling Pathway,Kinase,MAPK-Erk Signaling Pathway,MAPK-JNK Signaling Pathway,mTOR Signaling Pathway,NF-kB Signaling Pathway,PI3K-Akt Signaling Pathway,PI3K-Akt Signaling Pathway_PI3Ks and related,Protein Kinase C Signaling Pathway Pathway,Signal Transduction,T Cell Receptor Signaling Pathway,TGF-b-Smad Signaling Pathway,Toll-like Receptor Signaling Pathway,Translation Control,Translational Control_Regulation of eIF4 and p70 S6 Kinase,Warburg Effect,PIK3R2