Two-color fluorescent probes for imaging the dipole potential of cell plasma membranes

Biochim Biophys Acta. 2005 Jun 30;1712(2):128-36. doi: 10.1016/j.bbamem.2005.03.015.

Abstract

The dipole potential (Psi(d)) constitutes a large and functionally important part of the electrostatic potential of cell plasma membranes. However, its direct measurement is not possible. Herein, new 3-hydroxyflavone fluorescent probes were developed that respond strongly to Psi(d) changes by a variation of the intensity ratio of their two well-separated fluorescence bands. Using fluorescence spectroscopy with cell suspensions and confocal microscopy with adherent cells, we showed, for the first time, two-color fluorescence ratiometric measurement and visualization of Psi(d) in cell plasma membranes. Using this new tool, a heterogeneous distribution of this potential within the membrane was evidenced.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Adhesion
  • Cell Line
  • Cell Line, Tumor
  • Cell Membrane / metabolism*
  • Dose-Response Relationship, Drug
  • Fibroblasts / metabolism
  • Flavonoids / chemistry
  • Flavonoids / metabolism
  • Fluorescent Dyes / pharmacology*
  • Humans
  • Hydrogen-Ion Concentration
  • Ketocholesterols / chemistry
  • Lipid Bilayers / chemistry
  • Lipids / chemistry
  • Membrane Potentials
  • Mice
  • Microscopy, Confocal / methods*
  • Microscopy, Fluorescence / methods*
  • Models, Chemical
  • Phosphatidylcholines / chemistry
  • Phosphatidylglycerols / chemistry
  • Protons
  • Pyridinium Compounds / pharmacology
  • Static Electricity

Substances

  • 1-(3-sulfonatopropyl)-4-(beta-(2-(di-n-octylamino)-6-naphthyl)vinyl)pyridinium betaine
  • Flavonoids
  • Fluorescent Dyes
  • Ketocholesterols
  • Lipid Bilayers
  • Lipids
  • Phosphatidylcholines
  • Phosphatidylglycerols
  • Protons
  • Pyridinium Compounds
  • 6-ketocholestanol
  • 1,2-dioleoyl-sn-glycero-3-phosphoglycerol
  • 1,2-oleoylphosphatidylcholine
  • 3-hydroxyflavone