Please use this identifier to cite or link to this item:
Título : Transient cholesterol effects on nicotinic acetylcholine receptor cell-surface mobility
Autor : Almarza, Gonzalo 
Sánchez, Francisco 
Barrantes, Francisco José 
Fecha de publicación : 2014
Editorial : Public Library of Science
Resumen : Abstract: To what extent do cholesterol-rich lipid platforms modulate the supramolecular organization of the nicotinic acetylcholine receptor (AChR)? To address this question, the dynamics of AChR particles at high density and its cholesterol dependence at the surface of mammalian cells were studied by combining total internal reflection fluorescence microscopy and single-particle tracking. AChR particles tagged with a monovalent ligand, fluorescent α-bungarotoxin (αBTX), exhibited two mobile pools: i) a highly mobile one undergoing simple Brownian motion (16%) and ii) one with restricted motion (∼50%), the rest being relatively immobile (∼44%). Depletion of membrane cholesterol by methyl-α-cyclodextrin increased the fraction of the first pool to 22% and 33% after 15 and 40 min, respectively; the pool undergoing restricted motion diminished from 50% to 44% and 37%, respectively. Monoclonal antibody binding results in AChR crosslinking-internalization after 2 h; here, antibody binding immobilized within minutes ∼20% of the totally mobile AChR. This proportion dramatically increased upon cholesterol depletion, especially during the initial 10 min (83.3%). Thus, antibody crosslinking and cholesterol depletion exhibited a mutually synergistic effect, increasing the average lifetime of cell-surface AChRs∼10 s to ∼20 s. The instantaneous (microscopic) diffusion coefficient D2-4 of the AChR obtained from the MSD analysis diminished from ∼0.001 µm2 s(-1) to ∼0.0001-0.00033 µm2 s(-1) upon cholesterol depletion, ∼30% of all particles falling into the stationary mode. Thus, muscle-type AChR exhibits heterogeneous motional regimes at the cell surface, modulated by the combination of intrinsic (its supramolecular organization) and extrinsic (membrane cholesterol content) factors.
ISSN : 1932-6203 (online)
Disciplina: MEDICINA
DOI: 10.1371/journal.pone.0100346
Derechos: Acceso abierto
Appears in Collections:Artículos

Files in This Item:
File Description SizeFormat
transient-cholesterol-effects-nicotinic.pdf1,8 MBAdobe PDFThumbnail
Show full item record

Page view(s)

checked on Feb 28, 2021


checked on Feb 28, 2021

Google ScholarTM



This item is licensed under a Creative Commons License Creative Commons