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Phosphatidylinositol Phosphate (other)
Phosphatidylinositol phosphate may refer to: * Phosphatidylinositol 3-phosphate, also known as PI(3)P * Phosphatidylinositol 4-phosphate, also known as PI(4)P * Phosphatidylinositol 5-phosphate, also known as PI(5)P {{disambig Phospholipids ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphatidylinositol 3-phosphate
Phosphatidylinositol 3-phosphate (PtdIns3''P'') is a phospholipid found in cell membranes that helps to recruit a range of proteins, many of which are involved in protein trafficking, to the membranes. It is the product of both the class II and III phosphoinositide 3-kinases (PI 3-kinases) activity on phosphatidylinositol. PtdIns3''P'' is dephosphorylated by the myotubularin family of phosphatases, on the D3 position of the inositol ring, and can be converted to PtdIns(3,5)''P''2 by the lipid kinase PIKfyve. Both FYVE domains and PX domains – found in proteins such as SNX1, HGS, and EEA1 – bind to PtdIns3''P''. The majority of PtdIns3''P'' appears to be constitutively synthesised by the class III PI 3-kinase, PIK3C3 (Vps34), at endocytic membranes. Class II PI 3-kinases also appear to synthesise PtdIns3''P'', their activity however appears to be regulated by a range of stimuli, including growth factors. This suggests that specific pools of PtdIns3''P'' ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphatidylinositol 4-phosphate
Phosphatidylinositol-4-phosphate (PtdIns4''P'', PI-4-P, PI4P, or PIP) 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-phosphate-adaptor protein 1 and 2 ( PLEKHA3 and PLEKHA8). This three molecule complex recruits proteins that need to be carried to the cell membrane. 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. See also * Phosphatidylinositol 3-phosphate Phosphatidylinositol 3-phosphate (PtdIns3''P'') is a phospholipid found in cell membranes that helps to recruit a range of proteins, many of which are involved in protein trafficking, to the membranes. It is the product of both the class II and II ... * Phosphatidylinositol 5-phosphate * Phosphatidylin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphatidylinositol 5-phosphate
Phosphatidylinositol 5-phosphate (PtdIns5P) is a phosphoinositide, one of the phosphorylated derivatives of phosphatidylinositol (PtdIns), that are well-established membrane-anchored regulatory molecules. Phosphoinositides participate in signaling events that control cytoskeletal dynamics, intracellular membrane trafficking, cell proliferation and many other cellular functions. Generally, phosphoinositides transduce signals by recruiting specific phosphoinositide-binding proteins to intracellular membranes. Phosphatidylinositol 5-phosphate is one of the 7 known cellular phosphoinositides with less understood functions. It is phosphorylated on position D-5 of the inositol head group, which is attached via phosphodiester linkage to diacylglycerol (with varying chemical composition of the acyl chains, frequently 1-stearoyl-2-arachidonoyl chain). In quiescent cells, on average, PtdIns5P is of similar or higher abundance as compared to PtdIns3P and ~20-100-fold below the levels of PtdIn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |