Phosphatidylinositol polyphosphates

Sattler, M., Salgja, R., Shrikhande, G., Verma, S., Choi, J.L., Rohrschneider, L.R., and Griffin, J.D., 1997, The phosphatidylinositol polyphosphate 5-phosphatase SHIP and the protein tyrosine phosphatase SHP-2 form a complex in hematopoietic cells which can be regulated by BCR/ABL and growth factors. Oncogene, 15 2379-2384. 

The lysosomal acid sphingomyelinase (aSMase) isoform is inhibited by L-camitine, a cofactor of acyl-coenzyme A transport in mitochondria (107, 108), and by phosphatidylinositol polyphosphates, which occur in plant, yeast, and mammalian cells (109). 

The design and synthesis of phosphatidylinositol polyphosphates lipids (PIPn) headgroup scaffolds (69) from (68) that could be conveniently functionalized to obtain a number of derivatized analogues of use for different studies, have been presented by Best and co-workers (Scheme 13). ... 

Keywords Hsp90 IGF-IR Inositol polyphosphate mTor PDKl PI3K Phosphatidylinositol Phospholipids PKB... 

Stolz, L.E., Kuo, W.J., Longchamps, J., Sekhon, M. and York, J.D., 1998, INP51, a yeast inositol polyphosphate 5-phosphatase required for phosphatidylinositol 4,5-bisphosphate homeostasis and whose absence confers a cold-resistant phenotype. J. Biol. Chem. 273 11852-11861. 

Zhang, X., Hartz, P.A., Philip, E., Racusen, L.C., and Majerus, P.W., 1998, Cell lines from kidney proximal tubules of a patient with Lowe syndrome lack OCRL inositol polyphosphate 5-phosphatase and accumulate phosphatidylinositol 4,5-bisphosphate. J. Biol. Chem. 273 1574-1582. 

Other interfacial chemistries are found in juxtamem-brane domains of certain proteins that show a preferential interaction with specific lipids in their head group region. Important lipids involved in these interactions include the polyphosphate phosphatidylinositol lipids, cholesterol, gangliosides, and sphingomyelin. Interfacial chemistries play a role in the formation of microdomains and can determine the effective concentration of certain amphiphilic drugs in different membranes or even in different leaflets of the same membrane. 

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