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Phospholipase D2: functional interaction with caveolin in low-density membrane microdomains.

M Czarny·G Fiucci·Y Lavie·Y Banno·Y Nozawa·M Liscovitch
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Abstract

Low-density detergent-insoluble membrane domains contain caveolin-1 and are enriched in a phospholipase D activity that is not PLD1. Here we show that caveolin-rich fractions, prepared from HaCaT human keratinocytes by either detergent-based or detergent-free methods, contain PLD2. Caveolar membrane PLD activity is stimulated 2-fold by low concentrations (10-30 microM) of the caveolin-1 and caveolin-2 scaffolding domain peptides, whereas it is inhibited at higher concentrations of the peptides. Immunoisolated HA-tagged PLD1 and PLD2 are not stimulated by the peptides, although both enzymes retain sensitivity to their inhibitory effect. Down-regulation of caveolin-1 expression by treatment of the cells with acetyl-leucyl-leucyl-norleucinal decreased caveolar PLD activity by 50%. Similarly, expression of an active form of the sterol regulatory element-binding protein (SREBP(1-490)) down-regulated caveolin-1 expression by 50% and decreased caveolar PLD activity by 60%. These data identify the PLD activity in caveolin-rich membranes as PLD2 and provide in vivo evidence suggesting that caveolin-1 regulates PLD2 activity.

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CCAAT-Enhancer-Binding ProteinsCaveolin 1CaveolinsCell ExtractsCell LineCell MembraneDNA-Binding ProteinsDetergentsDown-RegulationEnzyme ActivationHumansKeratinocytesMembrane ProteinsNuclear ProteinsPeptidesPhospholipase DSterol Regulatory Element Binding Protein 1Transcription FactorsJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.

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M Czarny, G Fiucci, Y Lavie, Y Banno, Y Nozawa, M Liscovitch. 2000-02-11. Phospholipase D2: functional interaction with caveolin in low-density membrane microdomains.. https://doi.org/10.1016/s0014-5793(00)01174-1

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