title: Changes in plasma membrane surface potential of PC12 cells as measured by Kelvin probe force microscopy.
abstract: The plasma membrane of a cell not only works as a physical barrier but also mediates the signal relay between the extracellular milieu and the cell interior. Various stimulants may cause the redistribution of molecules, like lipids, proteins, and polysaccharides, on the plasma membrane and change the surface potential (Φ(s)). In this study, the Φ(s)s of PC12 cell plasma membranes were measured by atomic force microscopy in Kelvin probe mode (KPFM). The skewness values of the Φ(s)s distribution histogram were found to be mostly negative, and the incorporation of negatively charged phosphatidylserine shifted the average skewness values to positive. After being treated with H(2)O(2), dopamine, or Zn(2+), phosphatidylserine was found to be translocated to the membrane outer leaflet and the averaged skewness values were changed to positive values. These results demonstrated that KPFM can be used to monitor cell physiology status in response to various stimulants with high spatial resolution.
authors.affiliation: Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, Taiwan.
authors.forename: Chia-Chang
authors.initials: CC
authors.lastname: Tsai
authors.forename: Hui-Hsing
authors.initials: HH
authors.lastname: Hung
authors.forename: Chien-Pang
authors.initials: CP
authors.lastname: Liu
authors.forename: Yit-Tsong
authors.initials: YT
authors.lastname: Chen
authors.forename: Chien-Yuan
authors.initials: CY
authors.lastname: Pan
mesh_terms: D000818:Animals; D002462:Cell Membrane / Q000378:metabolism / Q000502:physiology*; D004298:Dopamine / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000378:metabolism; D008564:Membrane Potentials / Q000502:physiology; D008823:Micelles; D018625:Microscopy, Atomic Force / Q000379:methods; D018384:Oxidative Stress / Q000502:physiology; D016716:PC12 Cells; D010718:Phosphatidylserines / Q000378:metabolism; D051381:Rats; D015032:Zinc / Q000378:metabolism
chemical_list: D008823:Micelles; D010718:Phosphatidylserines; D006861:Hydrogen Peroxide; D015032:Zinc; D004298:Dopamine