Re-examination of the mechanisms regulating nuclear inositol lipid metabolism

• Published in: FEBS Letters 2001-09, Vol.505 (1), p.1-6
• Main Authors: Martelli, Alberto M., Bortul, Roberta, Tabellini, Giovanna, Aluigi, Michela, Peruzzi, Daniela, Bareggi, Renato, Narducci, Paola, Cocco, Lucio
• Format: Article
• Language: English
• Subjects: Animals; Cell Nucleus - metabolism; DAG, 1,2-diacylglycerol; G protein; Humans; IGF-I, insulin-like growth factor-I; Inositol - metabolism; Inositol lipid; Ins(1,4,5)P3, inositol 1,4,5-trisphosphate; Isoenzymes - metabolism; Lipid Metabolism; MAP, mitogen-activated protein; MEL, mouse erythroleukemia; Mitogen-activated protein kinase; NGF, nerve growth factor; Nucleus; PH, pleckstrin homology; Phosphatidylinositol 3-kinase; Phosphatidylinositol 3-Kinases - metabolism; Phosphatidylinositols - metabolism; Phospholipase C beta; Phospholipase C-β1; Phosphorylation; PI-PLC, phosphoinositide-specific phospholipase C; PI3K, phosphatidylinositol 3-kinase; PIKE, phosphoinositide kinase enhancer; PKA, protein kinase A; PKC, protein kinase C; Protein kinase C; PtdIns(3,4,5)P3, phosphatidylinositol 3,4,5-trisphosphate; PtdIns(4,5)P2, phosphatidylinositol 4,5-bisphosphate; Type C Phospholipases - metabolism
• ISSN: 0014-5793; 1873-3468
• DOI: 10.1016/S0014-5793(01)02752-1

Although inositol lipids constitute only a very minor proportion of total cellular lipids, they have received immense attention by scientists since it was discovered that they play key roles in a wide range of important cellular processes. In the late 1980s, it was suggested that these lipids are also present within the cell nucleus. Albeit the early reports about the intranuclear localization of phosphoinositides were met by skepticism and disbelief, compelling evidence has subsequently been accumulated convincingly showing that a phosphoinositide cycle is present at the nuclear level and may be activated in response to stimuli that do not activate the inositol lipid metabolism localized at the plasma membrane. Very recently, intriguing new data have highlighted that some of the mechanisms regulating nuclear inositol lipid metabolism differ in a substantial way from those operating at the cell periphery. Here, we provide an overview of recent findings regarding the regulation of both nuclear phosphatidylinositol 3-kinase and phosphoinositide-specific phospholipase C-β1.