Nuclear expression of diacylglycerol kinases: possible involvement in DNA replication.
The existence of intranuclear lipid-dependent signal transduction systems has been demonstrated by several independent groups. Remarkably, intranuclear lipid-dependent signal transduction pathways are regulated independently from their membrane/cytosolic counterparts. A sizable body of evidence suggests that nuclear lipid signaling controls critical biological functions such as cell proliferation, differentiation, and apoptosis. Diacylglycerol (DG) is a fundamental lipid second messenger which is produced in the nucleus. Since the levels of nuclear DG fluctuate during the cell cycle progression, it has been suggested that this lipid second messenger has important regulatory roles. Most likely, nuclear DG serves as a chemoattractant for some isoforms of protein kinase C that migrate to the nucleus in response to a variety of agonists. The nucleus also contains diacylglycerol kinases (DGKs), i.e. the enzymes that, by converting DG into phosphatidic acid (PA), terminate DG-dependent events. This review aims at highlighting the different isozymes of DGKs present within the nucleus as well as at discussing their potential functions with particular emphasis placed on DNA replication.
Evangelisti
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Dipartimento di Scienze Anatomiche Umane e Fisiopatologia dell'Apparato Locomotore, Sezione di Anatomia, Università degli Studi di Bologna, via Irnerio 48, 40126 Bologna, Italy.
Bortul
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Tabellini
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Papa
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Cocco
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Martelli
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D000818:Animals; D002467:Cell Nucleus / Q000201:enzymology* / Q000235:genetics; D004261:DNA Replication; D019852:Diacylglycerol Kinase / Q000096:biosynthesis* / Q000235:genetics; D015971:Gene Expression Regulation, Enzymologic; D006801:Humans; D007527:Isoenzymes / Q000096:biosynthesis / Q000235:genetics; D050356:Lipid Metabolism / Q000235:genetics; D051379:Mice; D051381:Rats
D007527:Isoenzymes; D019852:Diacylglycerol Kinase