Phosphatidylinositol (3,4,5)-trisphosphate (PIP3) (PIP3)

Phosphatidylinositol (3,4,5)-trisphosphate (PIP3) is a critical phospholipid second messenger located within the plasma membrane that plays a central role in intracellular signaling [PubChem CID 445354]. It is primarily generated through the phosphorylation of phosphatidylinositol (4,5)-bisphosphate (PIP2) by the enzyme Phosphoinositide 3-kinase (PI3K) in response to growth factor stimulation [PMID: 29033137]. Once produced, PIP3 acts as a docking site for various signaling proteins containing Pleckstrin Homology (PH) domains, such as AKT and PDK1, thereby initiating the PI3K/AKT/mTOR signaling cascade [PMID: 11514514]. This pathway is essential for regulating fundamental cellular processes, including growth, survival, proliferation, and glucose metabolism [PMID: 22561375]. Dysregulation of PIP3 levels, often caused by mutations in PI3K or the loss of the antagonist phosphatase PTEN, is a hallmark of numerous cancers and metabolic disorders like type 2 diabetes [PMID: 24469054]. Consequently, PIP3 is a major focus of therapeutic intervention, with numerous drugs designed to inhibit its synthesis or block its downstream effector interactions to treat malignancy and inflammatory conditions [PMID: 30622360].

Other names

PtdIns(3,4,5)P3Phosphatidylinositol 3,4,5-trisphosphate1-Phosphatidyl-1D-myo-inositol 3,4,5-trisphosphatePhosphatidylinositol-3,4,5-trisphosphate

Inhibition of Phosphoinositide 3-kinase (PI3K) to prevent PIP3 production; Competitive inhibition of Pleckstrin Homology (PH) domain binding; Dephosphorylation by PTEN phosphatase [PMID: 29033137, PMID: 30622360].