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Updated: Sep 23, 2026

Localization of Plasma Membrane and Intracellular Neuronal Nicotinic Acetylcholine Receptors Using Quantitative Imaging in Mammalian Cells
Published on: December 19, 2025
N-glycosylation sites on the nicotinic ACh receptor subunits regulate receptor channel desensitization and
1Department of Physiology, Hyogo College of Medicine, 1-1 Mukogawa-cho, Nishinomiya 663-8501, Japan. tomoyuki@hyo-med.ac.jp
Abstract:
The present study investigated the effects of N-glycosylation sites on Torpedo acetylcholine (ACh) receptors expressed in Xenopus oocytes by monitoring whole-cell membrane currents and single-channel currents from excised patches. Receptors with the mutant subunit at the asparagine residue on the conserved N-glycosylation site (mbetaN141D, mgammaN141D, or mdeltaN143D) or the serine/threonine residue (mbetaT143A, mgammaS143A, or mdeltaS145A) delayed the rate of current decay as compared with wild-type receptors, and the most striking effect was found with receptors with mbetaT143A or mgammaS143A. For wild-type receptors, the lectin concanavalin A, that binds to glycosylated membrane proteins with high affinity, mimicked this effect. Receptors with mbetaN141D or mdeltaN143D exhibited lower single-channel conductance, but those with mbetaT143A, mgammaS143A, or mdeltaS145A otherwise revealed higher conductance than wild-type receptors. Mean opening time of single-channel currents was little affected by the mutation. N-glycosylation sites, thus, appear to play a role in the regulation of ACh receptor desensitization and ion permeability.
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