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    Spatiotemporal control of endocytosis by phosphatidylinositol-3,4-bisphosphate
    Nature (2013)
    York PosorMarielle Eichhorn-GruenigDmytro PuchkovJohannes SchönebergAlexander Ullrich
    Phosphatidylinositol 4,5-bisphosphate
    Citations (376)
    Phosphatidylinositol 3-kinase related kinases
    Current Opinion in Immunology (1996)
    Robert T. Abraham
    TANK-binding kinase 1
    Citations (61)
    A homogeneous and nonisotopic assay for phosphatidylinositol 4-kinases
    Analytical Biochemistry (2011)
    Andrew W. TaiNaveen BojjireddyTamás Balla
    Citations (58)
    Pathways for phosphoinositide synthesis
    Chemistry and Physics of Lipids (1999)
    Kimberley F. ToliasLewis C. Cantley
    Second messenger system
    Citations (85)
    Phosphatidylinositol 5-phosphate 4-kinase γ (PI5P4Kγ), a lipid signalling enigma
    Advances in Biological Regulation (2015)
    Maria-Luisa GiudiciJonathan H. ClarkeRobin F. Irvine
    The phosphatidylinositol 5-phosphate 4-kinases (PI5P4Ks) are an important family of enzymes, whose physiological roles are being teased out by a variety of means. Phosphatidylinositol-5-phosphate 4-kinase γ (PI5P4Kγ) is especially intriguing as its in vitro activity is very low. Here we review what is known about this enzyme and discuss some recent advances towards an understanding of its physiology. Additionally, the effects of the ATP-competitive inhibitor I-OMe Tyrphostin AG-538 on all three mammalian PI5P4Ks was explored, including two PI5P4Kγ mutants with altered ATP- or PI5P-binding sites. The results suggest a strategy for targeting non-ATP binding sites on inositol lipid kinases.
    Signalling
    Citations (10)
    Phosphatidylinositol 4-kinases, phosphatidylinositol 4-phosphate and cancer
    Cancer Letters (2012)
    Mark G. Waugh
    Pleckstrin homology domain
    Citations (54)
    Phosphatidylinositol phosphate kinases.
    PubMed (2004)
    Giudici MlHinchliffe KaIrvine Rf
    Citations (20)
    [22] Phosphatidylinositol 4-kinases and phosphatidylinositol-4-phosphate 5-kinases from bovine brain brain membranes
    Methods in enzymology on CD-ROM/Methods in enzymology (1992)
    Albrecht MoritzJand WestermanP.N.E. de GraanK.W.A. Wirtz
    Citations (14)
    In vitro interaction of phosphoinositide-4-phosphate 5-kinases with rac
    Methods in enzymology on CD-ROM/Methods in enzymology (2000)
    Kimberley F. ToliasCatherine L. Carpenter
    Inositol phosphate
    Citations (16)
    Characterization of phosphatidylinositol and phosphatidylinositol-4-phosphate kinases in human neutrophils.
    The Journal of Immunology (1988)
    M C PikeClaudia Arndt
    Phosphodiesteric cleavage of phosphatidylinositol-4,5-bisphosphate (PtdIns-4,5-P2) is required for transmembrane signaling by chemoattractants in human polymorphonuclear leukocytes (PMN). Considering the importance of PtdIns-4,5-P2 as a reservoir for second messenger substances, we have characterized the enzyme system that synthesizes this phospholipid in human PMN, consisting of kinases for phosphatidylinositol (PtdIns) and phosphatidylinositol-4-phosphate (PtdIns-4-P). The preferred phosphate donor for both enzymes was ATP as compared with GTP. The respective Km for ATP for PtdIns kinase and PtdIns-P kinase were 0.049 +/- 0.013 and 0.062 +/- 0.005 mM and for GTP were 0.242 +/- 0.016 and 0.186 +/- 0.037 mM. PtdIns stimulated the activity of PtdIns kinase to a greater extent than PtdIns-4-P kinase. PtdIns-4-P inhibited the activity of detergent-solubilized PtdIns kinase and stimulated particulate PtdIns-4-P kinase, whereas both enzymes exhibited substrate inhibition to PtdIns-4,5-P2. Mg2+ was the preferred cation for both enzymes, but the apparent Km values (4.1 +/- 0.9 mM for PtdIns kinase and 1.0 +/- 0.7 mM for PtdIns-4-P kinase) were significantly different (p less than 0.005). Mn2+ partially substituted for Mg2+, and both enzymes were inhibited by Ca2+. The polyamine spermine stimulated PtdIns-4-P kinase activity to a greater extent and at lower concentrations than PtdIns kinase. PtdIns kinase was easily solubilized in both Triton X-100 and Nonidet P-40, whereas PtdIns-4-P kinase remained in a detergent-nonextractable membrane fraction. These findings demonstrate that the enzyme system in human PMN that forms PtdIns-4,5-P2 is composed of two distinct enzymes with similar characteristics.
    Citations (23)