phosphatidylinositol

phosphatidylinositol
A phosphatidic acid combined with inositol found in biomembranes and a precursor to certain cellular signals. Sometimes referred to as inositide. SYN: phosphoinositide.
- p. 4,5-bisphosphate (PIP2, PtdIns(4,5)P2) p. with two additional sites of phosphorylation; an important constituent of cell membrane phospholipids as well as a precursor of the second messengers, diacylglycerol and inositol 1,4,5-trisphosphate.
- p. 4-phosphate the intermediate in the biosynthesis of p. 4,5-bisphosphate from p..
- p. synthase an enzyme that catalyzes the reaction of CDP-diacylglycerol with inositol to form CMP and p.; found in the endoplasmic reticulum.

* * *

phos·pha·ti·dyl·ino·si·tol (PI) (fos″fə-ti″dəl-ĭ-noґsĭ-tol) a phospholipid in which the sugar inositol is attached to the phosphate group of phosphatidic acid by an ester linkage and the fatty acyl groups are usually arachidonate and stearate; additional phosphates can be attached to the sugar. It is a minor constituent of cell membranes found primarily in the plasma membrane. It is converted by specific kinases to mono- and diphosphorylated forms, phosphoinositides involved in hormonally activated calcium mobilization.

Medical dictionary. 2011.

Игры ⚽ Нужен реферат?

Look at other dictionaries:

  • Phosphatidylinositol — (abbreviated PtdIns, or PI) is a minor phospholipid component in the cytosolic side of eukaryotic cell membranes. Being an amphiphile, this molecule possesses polymorphic behaviour, that is currently a topic of research in academic study.… …   Wikipedia

  • Phosphatidylinositol — Le phosphatidylinositol Le phosphatidylinositol est un phospholipide, constituant des membranes cellulaires. Cette molécule est composée d un groupement phosphatidyl (deux acides gras estérifiés sur une molécules de glycérol, elle même liée de… …   Wikipédia en Français

  • Phosphatidylinositol — Lecithine (deutsch: Lezithine, altgriechisch: λέκιθος = Eidotter) ist der klassische Name für eine Gruppe chemischer Verbindungen, die so genannten Phosphatidylcholine. Dabei handelt es sich um Lipide, genauer Phospholipide, die sich aus… …   Deutsch Wikipedia

  • Phosphatidylinositol 1,4,5 tris phosphate — Phosphatidylinositol Le phosphatidylinositol Le phosphatidylinositol est un phospholipide, constituant des membranes cellulaires. Cette molécule est composée d un groupement phosphatidyl (deux acides gras estérifiés sur une molécules de glycérol …   Wikipédia en Français

  • Phosphatidylinositol phosphate kinases — (PIPK) are kinases that phosphorylate the phosphoinositides PtdIns P and PtdIns P 2 that are derivatives of phosphatidylinositol (PtdIns). It has been found that PtdIns is only phosphorylated on three (3,4,5) of its five hydroxyl groups, possibly …   Wikipedia

  • Phosphatidylinositol bisphosphate — may refer to: * Phosphatidylinositol (3,4) bisphosphate * Phosphatidylinositol (3,5) bisphosphate * Phosphatidylinositol (4,5) bisphosphate …   Wikipedia

  • Phosphatidylinositol (3,5)-bisphosphate — (PtdIns(3,5) P 2) is a minor phospholipid component of cell membranes, yet important in distinguishing cell compartments. The generation of PtdIns(3,5) P 2 in internal membranes by the lipid kinase PIKfyve recruits a number of important proteins… …   Wikipedia

  • Phosphatidylinositol transfer protein, alpha — Phosphatidylinositol transfer protein, alpha, also known as PITPNA, is a human gene. PBB Summary section title = summary text = Phosphatidylinositol transfer proteins are a diverse set of cytosolic phospholipid transfer proteins that are… …   Wikipedia

  • Phosphatidylinositol (3,4,5)-trisphosphate — (PtdIns(3,4,5) P 3) commonly abbreviated to PIP3 is the product of the class I phosphoinositide 3 kinases (PI 3 kinases) activity on phosphatidylinositol (4,5) bisphosphate. PtdIns(3,4,5) P 3 is dephophosphorylated by the phosphatase, PTEN on the …   Wikipedia

  • Phosphatidylinositol 4-phosphate — (PtdIns4 P ) is a precursor of Phosphatidylinositol (4,5) bisphosphate. PtdIns4 P is prevalent in the membrane of the Golgi apparatus.In the Golgi apparatus, PtdIns4 P binds to the GTP binding protein ARF and to effector proteins, including four… …   Wikipedia

  • Phosphatidylinositol phosphate — Phosphatidylinositol phosphates (PIPs) are a class of phospholipids similar to phosphatidylinositols that are also known to have polymorphic behaviour. References * J. M. Seddon, R. H. Templer. Polymorphism of Lipid Water Systems , from the… …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”