Phosphatidylinositol-4-phosphate (PtdIns4''P'', PI-4-P, PI4P, or PIP) is a precursor of

phosphatidylinositol (4,5)-bisphosphate Phosphatidylinositol 4,5-bisphosphate or PtdIns(4,5)''P''2, also known simply as PIP2 or PI(4,5)P2, is a minor phospholipid component of cell membranes. PtdIns(4,5)''P''2 is enriched at the plasma membrane where it is a substrate for a number of ...

. PtdIns4''P'' is prevalent in the membrane of the

Golgi apparatus The Golgi apparatus (), also known as the Golgi complex, Golgi body, or simply the Golgi, is an organelle found in most eukaryotic cells. Part of the endomembrane system in the cytoplasm, it packages proteins into membrane-bound vesicles ins ...

. In the

, PtdIns4''P'' binds to the

GTP-binding protein G proteins, also known as guanine nucleotide-binding proteins, are a family of proteins that act as molecular switches inside cells, and are involved in transmitting signals from a variety of stimuli outside a cell to its interior. Their ac ...

ARF ARF may refer to: Organizations * Advertising Research Foundation * Animal Rescue Foundation * Armenian Revolutionary Federation * ASEAN Regional Forum People * Cahit Arf (1910–1997), Turkish mathematician Science, medicine, and mathematics * ...

and to

effector protein In biochemistry, an effector molecule is usually a small molecule that selectively binds to a protein and regulates its biological activity. In this manner, effector molecules act as ligands that can increase or decrease enzyme activity, gene e ...

s, including four-phosphate-adaptor protein 1 and 2 ( PLEKHA3 and

PLEKHA8 Pleckstrin homology domain containing A8 is a protein that in humans is encoded by the PLEKHA8 gene In biology, the word gene (from , ; "... Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''g ...

). This three molecule complex recruits proteins that need to be carried to the

cell membrane The cell membrane (also known as the plasma membrane (PM) or cytoplasmic membrane, and historically referred to as the plasmalemma) is a biological membrane that separates and protects the interior of all cells from the outside environment ( ...

. There is now evidence that PI-4-P is capable of deforming lipid systems into tightly curved assemblies, this is consistent with similar behaviour observed in

phosphatidylinositol Phosphatidylinositol (or Inositol Phospholipid) consists of a family of lipids as illustrated on the right, where red is x, blue is y, and black is z, in the context of independent variation, a class of the phosphatidylglycerides. In such molecul ...

References

Phospholipids Signal transduction {{Biochemistry-stub

See also

References