title: Two-color fluorescent probes for imaging the dipole potential of cell plasma membranes.
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.
authors.affiliation: Laboratoire de Pharmacologie et Physicochimie des interactions cellulaires et moléculaires, UMR 7034 du CNRS, Faculté de Pharmacie, Université Louis Pasteur, 67401 Illkirch, France.
authors.forename: Vasyl V
authors.initials: VV
authors.lastname: Shynkar
authors.forename: Andrey S
authors.initials: AS
authors.lastname: Klymchenko
authors.forename: Guy
authors.initials: G
authors.lastname: Duportail
authors.forename: Alexander P
authors.initials: AP
authors.lastname: Demchenko
authors.forename: Yves
authors.initials: Y
authors.lastname: Mély
mesh_terms: D000818:Animals; D002448:Cell Adhesion; D002460:Cell Line; D045744:Cell Line, Tumor; D002462:Cell Membrane / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D005347:Fibroblasts / Q000378:metabolism; D005419:Flavonoids / Q000737:chemistry / Q000378:metabolism; D005456:Fluorescent Dyes / Q000494:pharmacology*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007653:Ketocholesterols / Q000737:chemistry; D008051:Lipid Bilayers / Q000737:chemistry; D008055:Lipids / Q000737:chemistry; D008564:Membrane Potentials; D051379:Mice; D018613:Microscopy, Confocal / Q000379:methods*; D008856:Microscopy, Fluorescence / Q000379:methods*; D008956:Models, Chemical; D010713:Phosphatidylcholines / Q000737:chemistry; D010715:Phosphatidylglycerols / Q000737:chemistry; D011522:Protons; D011726:Pyridinium Compounds / Q000494:pharmacology; D055672:Static Electricity
chemical_list: C089669:1-(3-sulfonatopropyl)-4-(beta-(2-(di-n-octylamino)-6-naphthyl)vinyl)pyridinium betaine; D005419:Flavonoids; D005456:Fluorescent Dyes; D007653:Ketocholesterols; D008051:Lipid Bilayers; D008055:Lipids; D010713:Phosphatidylcholines; D010715:Phosphatidylglycerols; D011522:Protons; D011726:Pyridinium Compounds; C063833:6-ketocholestanol; C051388:1,2-dioleoyl-sn-glycero-3-phosphoglycerol; C017251:1,2-oleoylphosphatidylcholine; C041477:3-hydroxyflavone