title: A fluorogenic, small molecule reporter for mammalian phospholipase C isozymes.
abstract: Phospholipase C isozymes (PLCs) catalyze the conversion of the membrane lipid phosphatidylinositol 4,5-bisphosphate (PIP(2)) into two second messengers, inositol 1,4,5-trisphosphate and diacylglycerol. This family of enzymes are key signaling proteins that regulate the physiological responses of many extracellular stimuli such as hormones, neurotransmitters, and growth factors. Aberrant regulation of PLCs has been implicated in various diseases including cancer and Alzheimer's disease. How, when, and where PLCs are activated under different cellular contexts are still largely unknown. We have developed a fluorogenic PLC reporter, WH-15, that can be cleaved in a cascade reaction to generate fluorescent 6-aminoquinoline. When applied in enzymatic assays with either pure PLCs or cell lysates, this reporter displays more than a 20-fold fluorescence enhancement in response to PLC activity. Under assay conditions, WH-15 has comparable K(m) and V(max) with the endogenous PIP(2). This novel reporter will likely find broad applications that vary from imaging PLC activity in live cells to high-throughput screening of PLC inhibitors.
authors.affiliation: Division of Medicinal Chemistry and Natural Products, The University of North Carolina at Chapel Hill, 27599, United States.
authors.forename: Weigang
authors.initials: W
authors.lastname: Huang
authors.forename: Stephanie N
authors.initials: SN
authors.lastname: Hicks
authors.forename: John
authors.initials: J
authors.lastname: Sondek
authors.forename: Qisheng
authors.initials: Q
authors.lastname: Zhang
mesh_terms: D000634:Aminoquinolines / Q000737:chemistry* / Q000378:metabolism; D055162:Biocatalysis; D002460:Cell Line; D002462:Cell Membrane / Q000737:chemistry / Q000378:metabolism; D004075:Diglycerides / Q000096:biosynthesis / Q000737:chemistry; D057075:Enzyme Assays / Q000379:methods*; D005456:Fluorescent Dyes / Q000737:chemistry* / Q000378:metabolism; D006801:Humans; D015544:Inositol 1,4,5-Trisphosphate / Q000031:analogs & derivatives* / Q000096:biosynthesis / Q000737:chemistry / Q000378:metabolism; D007527:Isoenzymes / Q000032:analysis / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000378:metabolism; D007700:Kinetics; D015335:Molecular Probes / Q000737:chemistry* / Q000378:metabolism; D015394:Molecular Structure; D008970:Molecular Weight; D019269:Phosphatidylinositol 4,5-Diphosphate / Q000737:chemistry / Q000378:metabolism; D013237:Stereoisomerism; D010738:Type C Phospholipases / Q000032:analysis* / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000378:metabolism*
chemical_list: D000634:Aminoquinolines; D004075:Diglycerides; D005456:Fluorescent Dyes; D007527:Isoenzymes; D015335:Molecular Probes; D019269:Phosphatidylinositol 4,5-Diphosphate; C561767:WH 15 compound; C032928:6-aminoquinoline; D015544:Inositol 1,4,5-Trisphosphate; D010738:Type C Phospholipases