Spin label EPR suggests the presence of cholesterol rich domains in cultured insect cell membranes

Biochem Biophys Res Commun. 2018 Nov 10;505(4):1038-1042. doi: 10.1016/j.bbrc.2018.10.011. Epub 2018 Oct 9.

Abstract

Different spin labels were incorporated to the membranes of cultured insect UFL-AG-286 cells in order to characterize their physical properties by Electron Paramagnetic Resonance spectroscopy (EPR). The spectrum of the spin label 12-SASL incorporated to cell membranes was similar as those obtained in membrane model systems composed of eggPC/cholesterol. However, the spectrum of the spin label CSL, chemically related to cholesterol, was drastically different in the two systems. Interestingly, when cell cholesterol content was reduced using methyl beta cyclodextrin, an EPR spectrum similar to those of model membranes was obtained. The analysis of these experiments suggests the existence of cholesterol rich regions in UFL-AG-286 cell membranes.

Keywords: Cholestane spin label; Cholesterol; Cultured insect cells; Lipid rafts; Membrane fluidity; Membrane nanodomains.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Membrane / chemistry*
  • Cells, Cultured
  • Cholesterol / chemistry*
  • Electron Spin Resonance Spectroscopy
  • Lepidoptera
  • Lipids / chemistry
  • Liposomes / chemistry
  • Spin Labels*

Substances

  • Lipids
  • Liposomes
  • Spin Labels
  • Cholesterol