Analysis of lipid raft molecules in the living brain slices. (October 2018)

• Record Type: Journal Article
• Authors: Kotani, Norihiro; Nakano, Takanari; Ida, Yui; Ito, Rina; Hashizume, Miki; Yamaguchi, Arisa; Seo, Makoto; Araki, Tomoyuki; Hojo, Yasushi; Honke, Koichi; Murakoshi, Takayuki
• Is Part Of: Neurochemistry international. Volume 119(2018)
• Page Start: 140
• Page End: 150
• Publication Date: 2018-10
• Subjects: Lipid raft -- EMARS -- Hippocampus -- Acute brain slice -- Depolarization; CNS Central nervous system -- EMARS Enzyme-mediated activation of radical sources -- aCSF artificial cerebrospinal fluid -- HRP Horse radish peroxidase -- CTxB Cholera toxin subunit B -- DIM Detergent insoluble membrane -- LC ESI-MS/MS Liquid chromatography with electron spray ionization mass spectrometry/mass spectrometry -- Na/K ATPase Sodium/Potassium ATPase -- NCAM Neural Cell Adhesion Molecule; Neurochemistry -- Periodicals; Neurochemistry -- Periodicals; Neurochimie -- Périodiques; Neurochemistry; Periodicals; 612.804205
• DOI: 10.1016/j.neuint.2017.08.012
• Languages: English
• ISSNs: 0197-0186

Abstract

Abstract: Neuronal plasma membrane has been thought to retain a lot of lipid raft components which play important roles in the neural function. Although the biochemical analyses of lipid raft using brain tissues have been extensively carried out in the past 20 years, many of their experimental conditions do not coincide with those of standard neuroscience researches such as neurophysiology and neuropharmacology. Hence, the physiological methods for lipid raft analysis that can be compatible with general neuroscience have been required. Herein, we developed a system to physiologically analyze ganglioside GM1-enriched lipid rafts in brain tissues using the "Enzyme-Mediated Activation of Radical Sources (EMARS)" method that we reported (Kotani N. et al. Proc. Natl. Acad. Sci. U S A 105, 7405–7409 (2008)). The EMARS method was applied to acute brain slices prepared from mouse brains in aCSF solution using the EMARS probe, HRP-conjugated cholera toxin subunit B, which recognizes ganglioside GM1. The membrane molecules present in the GM1-enriched lipid rafts were then labeled with fluorescein under the physiological condition. The fluorescein-tagged lipid raft molecules called "EMARS products" distributed differentially among various parts of the brain. On the other hand, appreciable differences were not detected among segments along the longitudinal axis of the hippocampus. We further developed a device to label the lipid raft molecules in acute hippocampal slices under two different physiological conditions to detect dynamics of the lipid raft molecules during neural excitation. Using this device, several cell membrane molecules including Thy1, known as a lipid raft resident molecule in neurons, were confirmed by the EMARS method in living hippocampal slices. Highlights: The EMARS method is useful for the analysis of physiological lipid raft molecules. Physiologically identified GM1-enriched lipid raft molecules in the mouse brain showed the regional specificity. The GM1-enriched lipid raft molecules in the hippocampus showed the homogeneity in terms of longitudinal locations.