title: Nanoscale effects of ethanol and naltrexone on protein organization in the plasma membrane studied by photoactivated localization microscopy (PALM).
abstract: BACKGROUND
  Ethanol affects the signaling of several important neurotransmitter and neuromodulator systems in the CNS. It has been recently proposed that ethanol alters the dynamic lateral organization of proteins and lipids in the plasma membrane, thereby affecting surface receptor-mediated cellular signaling. Our aims are to establish whether pharmacologically relevant levels of ethanol can affect the lateral organization of plasma membrane and cytoskeletal proteins at the nanoscopic level, and investigate the relevance of such perturbations for mu-opioid receptor (MOP) function.
  
  
  RESULTS
  We used Photoactivated Localization Microscopy with pair-correlation analysis (pcPALM), a quantitative fluorescence imaging technique with high spatial resolution (15-25 nm) and single-molecule sensitivity, to study ethanol effects on protein organization in the plasma membrane. We observed that short (20 min) exposure to 20 and 40 mM ethanol alters protein organization in the plasma membrane of cells that harbor endogenous MOPs, causing a rearrangement of the lipid raft marker glycosylphosphatidylinositol (GPI). These effects could be largely occluded by pretreating the cells with the MOP antagonist naltrexone (200 nM for 3 hours). In addition, ethanol induced pronounced actin polymerization, leading to its partial co-localization with GPI.
  
  
  CONCLUSIONS
  Pharmacologically relevant levels of ethanol alter the lateral organization of GPI-linked proteins and induce actin cytoskeleton reorganization. Pretreatment with the MOP antagonist naltrexone is protective against ethanol action and significantly reduces the extent to which ethanol remodels the lateral organization of lipid-rafts-associated proteins in the plasma membrane. Super-resolution pcPALM reveals details of ethanol action at the nanoscale level, giving new mechanistic insight on the cellular and molecular mechanisms of its action.
authors: Department of Molecular Medicine, Beckman Research Institute of the City of Hope Comprehensive Cancer Center, Duarte, California, United States of America ; Department of Chemistry, University of Hawaii at Manoa, Honolulu, Hawaii, United States of America.
authors: Steven J
authors: SJ
authors: Tobin
authors: Department of Molecular Medicine, Beckman Research Institute of the City of Hope Comprehensive Cancer Center, Duarte, California, United States of America ; Department of Chemistry, University of Hawaii at Manoa, Honolulu, Hawaii, United States of America.
authors: Eliedonna E
authors: EE
authors: Cacao
authors: Department of Chemistry, University of Hawaii at Manoa, Honolulu, Hawaii, United States of America.
authors: Daniel Wing Wo
authors: DW
authors: Hong
authors: Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.
authors: Lars
authors: L
authors: Terenius
authors: Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.
authors: Vladana
authors: V
authors: Vukojevic
authors: Department of Molecular Medicine, Beckman Research Institute of the City of Hope Comprehensive Cancer Center, Duarte, California, United States of America ; Department of Chemistry, University of Hawaii at Manoa, Honolulu, Hawaii, United States of America.
authors: Tijana
authors: T
authors: Jovanovic-Talisman
mesh_terms: D000199:Actins / Q000378:metabolism; D000818:Animals; D019556:COS Cells; D045744:Cell Line, Tumor; D002462:Cell Membrane / Q000737:chemistry* / Q000187:drug effects; D002522:Chlorocebus aethiops; D000431:Ethanol / Q000494:pharmacology*; D058851:GPI-Linked Proteins / Q000378:metabolism; D049452:Green Fluorescent Proteins / Q000378:metabolism; D006801:Humans; D008565:Membrane Proteins / Q000737:chemistry*; D008853:Microscopy / Q000379:methods*; D009271:Naltrexone / Q000494:pharmacology*; D053758:Nanoparticles / Q000737:chemistry*; D058105:Polymerization / Q000187:drug effects; D017450:Receptors, Opioid, mu / Q000378:metabolism
chemical_list: D000199:Actins; D058851:GPI-Linked Proteins; D008565:Membrane Proteins; D017450:Receptors, Opioid, mu; D049452:Green Fluorescent Proteins; D000431:Ethanol; D009271:Naltrexone