Skip to main content
Log in

Changes in channel properties of acetylcholine receptors during the time course of thiol chemical modifications

  • Published:
Pflügers Archiv Aims and scope Submit manuscript

Abstract

The changes occurring during chemical modification of thiol groups in single acetylcholine receptor (AChR) channels of BC3H-11 cells were examined by the patch-clamp technique in the “cell-attached” configuration. Treatment with either 1 mM or 5 mM dithiothreitol or with 5 mM N-ethylmaleimide (NEM) does not cause significant changes in the conductance and mean open time of the channels. However, reduction with dithiothreitol followed by alkylation with NEM produces modifications of AChRs. Under these conditions, channels activated by 2 μM acetylcholine show decreased open times (about 15-fold shorter for the mostmodified AChRs) and a slight reduction in single-channel current. Both changes are dependent on the time of exposure and concentration of NEM. The rate of occurrence of openings, however, changes little during NEM treatment. When reduced and alkylated AChRs are activated by 100 μM acetylcholine, clusters of short openings separated by silent periods of about 1 s are observed. The channel-open probability, determined for openings within a cluster, is decreased by about 10-fold when compared with control receptors. The observations at high agonist concentration indicate that the modified AChR is still able to undergo desensitization.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

References

  • Barrantes FJ (1980) Modulation of acetylcholine receptor states by thiol modification. Biochemistry 19:2957–2965

    Google Scholar 

  • Ben-Haim D, Dreyer F, Peper K (1975) Acetylcholine receptor: modification of synaptic gating mechanism after treatment with a disulfide bond reducing agent. Pflügers Arch 355:19–26

    Google Scholar 

  • Blanchard SG, Dunn SM, Raftery MA (1982) Effects of reduction and alkylation on ligand binding and cation transport by Torpedo californica acetylcholine receptor. Biochemistry 21:6258–6264

    Google Scholar 

  • Boulter J, Patrick J (1977) Purification of an acetylcholine receptor from a nonfusing muscle cell line. Biochemistry 16:4900–4908

    Google Scholar 

  • Boulter J, Luyten W, Evans K, Mason P, Ballivet M, Goldman D, Stengelin S, Martin G, Heinemann S, Patrick J (1985) Isolation of clone coding for the alpha-subunit of a mouse acetylcholine receptor. Neurosc 5:2545–2552

    Google Scholar 

  • Boulter JB, Goldman D, Evans K, Martin G, Stengelin S, Heinemann S, Patrick J (1986) Isolation, sequence and preparation of a cDNA clone coding for the gamma subunit of mouse muscle nicotinic acetylcholine receptor. J Neurosc Res 16:37–49

    Google Scholar 

  • Bregestovski PD, Iljin VI, Jurchenko OP, Veprintsev BN, Vulfius CA (1977) Acetylcholine receptor conformational transition on excitation masks disulphide bonds against reduction. Nature 270:71–73

    Google Scholar 

  • Claudio T, Ballivet M, Patrick J, Heinemann S (1983) Nucleotide and deduced amino acid sequences of Torpedo californica acetylcholine alpha-subunit. Proc Nat Acad Sc USA 80:1111–1115

    Google Scholar 

  • Damle VN, Karlin A (1980) Effects of agonists on the reactivity of the binding site disulfide in acetylcholine receptor from Torpedo californica. Biochemistry 19:3924–3932

    Google Scholar 

  • Delegeane AM, McNamee MG (1980) Independent activation of the acetylcholine receptor from Torpedo californica at two sites. Biochemistry 19:890–895

    Google Scholar 

  • Dennis M, Giraudat J, Kotzba-Hibert F, Goedlner M, Hirth C, Chang JY, Changeux JP (1986) A photoaffinity ligand of the acetylcholine binding site predominantly labels the region 179–207 of the alpha subunit on native acetylcholine receptor from Torpedo marmorata. FEBS Lett 207, 243–249

    Google Scholar 

  • de Souza Otero A, Hamilton SL (1984) Ligand-induced variations in the reactivity of thio groups of the (alpha)-subunit of the acetylcholine receptor form Torpedo californica. Biochemistry 23:2321–2328

    Google Scholar 

  • Gotti C, Frigerio F, Bolognesi M, Longhi R, Raccheti G, Clementi F (1988) Nicotinic acetylcholine receptor: a structural model for the alpa-subunit peptide 188–201, the putative binding site for the cholinergic agents. FEBS Lett 228:118–122

    Google Scholar 

  • Hamill OP, Marty A, Neher E, Sakman B, Sigworth FJ (1981) Improved patch-clamp techniques for high resolution current recording from cells and cell-free membrane patches. Pflügers Arch 391:85–100

    Google Scholar 

  • Jackson MB (1984) Spontaneous openings of the acetylcholine receptor channel. Proc Nat Acad Sci USA 81:3901–3904

    Google Scholar 

  • Kao P, Karlin A (1986) Acetylcholine receptor binding site contains a disulfide crosslink between adjacent half-cystinyl residues. JBiol Chem 261:8085–8088

    Google Scholar 

  • Kao PN, Dwork AJ, Kaldany R-R J, Silver ML, Widemann J, Stein S, Karlin A (1984) Identification of the half-cystine specifically labeled by an affinity label for the acetylcholine receptor binding site. J Biol Chem 259:11662–11665

    Google Scholar 

  • Kellaris KV, Ware DK (1989) Assessment of the number of free cysteines and isolation and identification of cystine-containing peptides from acetylcholine receptor. Biochemistry 28:3469–3482

    Google Scholar 

  • Landau EM, Ben-Haim D (1974) Acetylcholine noise: analysis after chemical modification of receptor. Science 185:944–946

    Google Scholar 

  • La Polla RJ, Mixter-Mayne K, Davidson N (1984) Isolation and characterization of a cDNA clone for the complete protein coding region of the delta-subunit of the mouse acetylcholine receptor. Proc Nat Acad Sci USA 81:7970–7974

    Google Scholar 

  • Lindstrom JM, Singer SJ, Lennox ES (1973) The effects of reducing and alkylating agents on the acetylcholine receptor activity of frog sartorius muscle. J Memb Biol 11:217–226

    Google Scholar 

  • Miller JV, Lukas RJ, Bennett EL (1979) Effects of thiol modification and Ca++ on agonist-specific state transitions of nicotinic acetylcholine receptor from Torpedo californica electroplax. Life Sci 24:1893–1900

    Google Scholar 

  • Mishina M, Tobimatsu T, Imoto K, Tanaka K, Fujita Y, Fukuda K, Kurasaki M, Hideo T, Morimoto Y, Hirose T, Inayama S, Takahashi T, Kuno M, Numa S (1985) Location of functional regions of acetylcholine receptor alpha-subunit by site-directed mutagenesis. Nature 31:364–369

    Google Scholar 

  • Neumann D, Gershoni J, Fredkin M, Fuchs S (1985) Antibodies to synthetic peptides as probes for the binding site on the alpha subunit of the acetylcholine receptor. Proc Nat Acad Sci USA 82:3490–3493

    Google Scholar 

  • Noda M, Takahashi H, Tanabe T, Toyosato M, Kikyotani S, Furutani Y, Hirose T, Takashima H, Inayama S, Miyata T, Numa S (1983) Structural homology of Torpedo californica acetylcholine receptor subunits. Nature 302:528–532

    Google Scholar 

  • Papke RL, Oswald RE (1989) Mechanisms of noncompetitive inhibiton of acetylcholine-induced single-channel currents. J Gen Physiol 93:785–811

    Google Scholar 

  • Papke RL, Millhauser G, Lieberman Z, Oswald RE (1988) Relationships of agonist properties to the single channel kinetics of nicotinic acetylcholine receptors. Biophys J 53:1–10

    Google Scholar 

  • Patrick I, McMillian J, Wolfson H, O'Brien JC (1977) Acetylcholine receptor metabolism in a nonfusing muscle cell line. J Biol Chem 252:2143–2153

    Google Scholar 

  • Sakmann B, Patlak J, Neher E (1980) Single acetylcholine activated channels show burst-kinetics in the presence of desensitzing concentrations of agonists. Nature 286:71–73

    Google Scholar 

  • Schiebler W, Lauffer L, Hucho F (1977) Acetylcholine receptor enriched membranes: acetylcholine binding and excitability after reduction. FEBS Lett 81:39–42

    Google Scholar 

  • Sigworth FJ, Sine SM (1987) Fitting and display of single channel dwell time histograms. Biophys J 52:1047–1054

    Google Scholar 

  • Sine SM (1988) Functional properties of human skeletal muscle acetylcholine receptors expressed by the TE671 cell line. J Biol Chem 263:18052–18062

    Google Scholar 

  • Sine SM, Steinbach JH (1984) Activation of a nicotinic acetylcholine receptor. Biophys J 45:175–185

    Google Scholar 

  • Sine SM, Steinbach JH (1986) Activation of acetylcholine receptors on clonal mammalian BC3H-1 cells by low concentrations of agonist. J Physiol 373:129–162

    Google Scholar 

  • Sine SM, Steinbach JH (1987) Activation of acetylcholine receptors on clonal mammalian BC3H-1 cells by high concentrations of agonist. J Physiol 385:325–359

    Google Scholar 

  • Sine SM, Taylor P (1979) Functional consequences of agonist-mediated state transitions in the cholinergic receptor. Studies on cultured muscle cells. J Biol Chem 254:3315–3325

    Google Scholar 

  • Sine SM, Taylor P (1980) The relationship between agonist occupation and the permeability response of the cholinergic receptor revealed by bound cobro alpha-toxin. J Biol Chem 255:10144–10156

    Google Scholar 

  • Sine SM, Taylor P (1981) Relationship between reversible antagonist occupancy and the functional capactiy of the acetylcholine receptor. J Biol Chem 256:6692–6699

    Google Scholar 

  • Sine SM, Claudio T, Sigworth FJ (1990) Activation of Torpedo acetylcholine receptors expressed in mouse fibroblasts: single channel current kinetics reveal distinct agonist binding affinites. J Gen Physiol 96:395–437

    Google Scholar 

  • Smith MM, Lindstrom J, Merlie JP (1987) Formation of the alphabungarotoxin binding site and assembly of the nicotinic acetylcholine receptor subunits occur in the endoplasmic reticulum. J Biol Chem 262:4367–4376

    Google Scholar 

  • Steinacker A, Zuazaga DC (1981) Changes in neuromuscular junction endplate current time constants produced by sulfhydryl reagents. Proc Natl Acad Sci USA 78:7806–7809

    Google Scholar 

  • Steinacker A, Zuazaga DC (1987) Further kinetic analysis of the chemically modified acetylcholine receptor. Pflügers Arch 409:555–560

    Google Scholar 

  • Stroud RM, Finer-Moore J (1985) Acetylcholine receptor structure, function, and evolution. Annu Rev Cell Biol 1:317–351

    Google Scholar 

  • Walker JW, Lukas RJ, McNamee MG (1981) Effects of thio-group modifications on the ion permeability control and ligand binding properties of Torpedo californica acetylcholine receptor. Biochemistry 20:2191–2199

    Google Scholar 

  • Walker JW, Richardson CA, McNamee MG (1984) Effects of thiogroup modification on ion flux activation and inactivation kinetics. Biochemistry 23:2329–2338

    Google Scholar 

  • Yee AS, Corley DE, McName MG (1986) Thiol-group modification of Torpedo californica acetylcholine receptor: Subunit localization and effects on function. Biochemistry 25:2110–2119

    Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Rights and permissions

Reprints and permissions

About this article

Cite this article

Bouzat, C., Barrantes, F.J. & Sigworth, F.J. Changes in channel properties of acetylcholine receptors during the time course of thiol chemical modifications. Pflügers Archiv 418, 51–61 (1991). https://doi.org/10.1007/BF00370451

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF00370451

Key words

Navigation