Phosphatidylinositols identification

Caro, L., Tettelin, H., Vossen, J., Ram, A., van den Ende, H., and Klis, F. (1997). In silico identification of glycosyl-phosphatidylinositol-anchored plasma-membrane and cell wall proteins of Saccharomyces cerevisiae. Yeast 13, 1477—1489. 

Fukami, K., Sawada, N., Endo, T., and Takenawa, T. (1996). Identification of a phosphatidylinositol 4,5-bisphosphate-binding site in chicken skeletal muscle alpha-actinin./ Biol. Chem. 271, 2646-2650. 

As in a musical composition, there is a major chord, and on most occasions there is a minor chord. The same can be applied to phosphatidylinositol and its phosphorylated derivatives. Immediately above, there was mention of three major inositol-containing phosphoglycerides. Over the past few years, identification of so-called minor inositol phosphoglycerides has received in-... 

Positive identification of the various phosphatidylinositols can be frustrating due to the small amounts actually present in many cells. This latter point is... 

Hoppe, H.C., de Wet, B.J., Cywes, C., Daffe, M., and Ehlers, M.R., 1997, Identification of phosphatidylinositol mannoside as a mycobacterial adhesin mediating both direct and opsonic binding to non phagocytic mammalian cells. Infect. Immun. 65 3896—3905. 

Dove, S.K., Lloyd, C.W., and Drbak, B.K., 1994, Identification of a phosphatidylinositol 3-hydroxy kinase in plant cells Association with the cytoskeleton. Biochem. J. 303 347-350. 

Meijer, H.J.G., Berrie, C.P., Iurisci, C., Divecha, N., Musgrave, A. and Munnik, T., 2001b, Identification of a new polyphosphoinositide in plants, phosphatidylinositol 5-monophosphate (PtdIns5P), and its accumulation upon osmotic stress. Biochem. J. 360 491—498. 

Whitley, P., Reaves, B.J., Hashimoto, M., Riley, A.M., Potter, B.VL. and Holman, G.D., 2003, Identification of mammalian Vps24p as an effector of phosphatidylinositol 3,5-bisphosphate-dependent endosome compartmentalization. J. Biol. Chem. 278 38786-38795. 

B. C. Berk, R. Aebersold and M. A. Corson, Identification of flow-dependent endothelial nitric-oxide synthase phosphorylation sites by mass spectrometry and regulation of phosphorylation and nitric oxide production by the phosphatidylinositol 3-kinase inhibitor LY294002. J Biol Chem 274, 30101-30108 (1999). 

When the acidic lipids of soybean cells heavily pre-labelled with [ P]Pi were resolved by 2-D TLC, no trace of radioactivity could be detected in the position occupied by a sample of authentic PI(4,5)P2 run on the same plate [34]. However [ P]-label was found at the location of a phosphatidylinositol 4-phosphate (PI(4)P) standard. This is only a preliminary to the process of proper identification. Co-chromatography of radioactivity, whether from p P]-Pi or [ H]-inositol, with a phosphoinositide standard in 1 -D TLC is not acceptable evidence of identity. It has subsequently been shown that suspension cultured cells of tomato and carrot callus also do not appear to contain detectable levels of PI(4,5)P2 [39]. 

PI5P-DiC8] and enantiomeric, unnatural e t-phosphatidylinositol-5-phosphate-DiC8 (12)-[e t-PI5P-DiC8] have been carried out by Miller and co-workers. Syntheses of both molecules enabled identification and further explanation of their cellular functions and possible alternating roles. 

Here, our membrane protein is the FYVE domain (which is named for its identification with four proteins (Fablip, YOTB, Vaclp, EEAI) and the ligand is Ptdlns(3)P, an abbreviation for phosphatidylinositole-3-phosphate. 

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