title: A FRET sensor enables quantitative measurements of membrane charges in live cells.
abstract: Membrane charge has a critical role in protein trafficking and signaling. However, quantification of the effective electrostatic potential of cellular membranes has remained challenging. We developed a fluorescence membrane charge sensor (MCS) that reports changes in the membrane charge of live cells via Förster resonance energy transfer (FRET). MCS is permanently attached to the inner leaflet of the plasma membrane and shows a linear, reversible and fast response to changes of the electrostatic potential. The sensor can monitor a wide range of cellular treatments that alter the electrostatic potential, such as incorporation and redistribution of charged lipids and alterations in cytosolic ion concentration. Applying the sensor to T cell biology, we used it to identify charged membrane domains in the immunological synapse. Further, we found that electrostatic interactions prevented spontaneous phosphorylation of the T cell receptor and contributed to the formation of signaling clusters in T cells.
authors.affiliation: EMBL Australia Node in Single Molecule Science, School of Medical Sciences, University of New South Wales, Sydney, New South Wales, Australia.|ARC Centre of Excellence in Advanced Molecular Imaging, University of New South Wales, Sydney, New South Wales, Australia.
authors.forename: Yuanqing
authors.initials: Y
authors.lastname: Ma
authors.affiliation: EMBL Australia Node in Single Molecule Science, School of Medical Sciences, University of New South Wales, Sydney, New South Wales, Australia.|ARC Centre of Excellence in Advanced Molecular Imaging, University of New South Wales, Sydney, New South Wales, Australia.
authors.forename: Yui
authors.initials: Y
authors.lastname: Yamamoto
authors.affiliation: EMBL Australia Node in Single Molecule Science, School of Medical Sciences, University of New South Wales, Sydney, New South Wales, Australia.|ARC Centre of Excellence in Advanced Molecular Imaging, University of New South Wales, Sydney, New South Wales, Australia.
authors.forename: Philip R
authors.initials: PR
authors.lastname: Nicovich
authors.affiliation: EMBL Australia Node in Single Molecule Science, School of Medical Sciences, University of New South Wales, Sydney, New South Wales, Australia.|ARC Centre of Excellence in Advanced Molecular Imaging, University of New South Wales, Sydney, New South Wales, Australia.
authors.forename: Jesse
authors.initials: J
authors.lastname: Goyette
authors.affiliation: EMBL Australia Node in Single Molecule Science, School of Medical Sciences, University of New South Wales, Sydney, New South Wales, Australia.
authors.forename: Jérémie
authors.initials: J
authors.lastname: Rossy
authors.affiliation: School of Chemistry and Australian Centre of NanoMedicine, University of New South Wales, Sydney, New South Wales, Australia.|ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, University of New South Wales, Sydney, New South Wales, Australia.
authors.forename: J Justin
authors.initials: JJ
authors.lastname: Gooding
authors.affiliation: EMBL Australia Node in Single Molecule Science, School of Medical Sciences, University of New South Wales, Sydney, New South Wales, Australia.|ARC Centre of Excellence in Advanced Molecular Imaging, University of New South Wales, Sydney, New South Wales, Australia.
authors.forename: Katharina
authors.initials: K
authors.lastname: Gaus
mesh_terms: D002462:Cell Membrane / Q000502:physiology*; D031541:Fluorescence Resonance Energy Transfer / Q000379:methods*; D006801:Humans; D019169:Jurkat Cells; D008164:Luminescent Proteins / Q000378:metabolism*; D008564:Membrane Potentials / Q000502:physiology*; D008565:Membrane Proteins / Q000502:physiology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D055672:Static Electricity
chemical_list: D008164:Luminescent Proteins; D008565:Membrane Proteins