Binds to activated (phosphorylated) protein-tyrosine kinases through its SH2 domain and regulates their kinase activity. During insulin stimulation, it also binds to IRS-1. Heterodimer of a regulatory subunit PIK3R3 and a p110 catalytic subunit (PIK3CA, PIK3CB or PIK3CD). Interacts with AXL. Highest levels in brain and testis. Lower levels in adipose tissue, kidney, heart, lung and skeletal muscle. Belongs to the PI3K p85 subunit family. 3 isoforms of the human protein are produced by alternative splicing. Note: This description may include information from UniProtKB.
Protein type: Kinase, lipid; Motility/polarity/chemotaxis