The Acetylcholine Receptor

Klett, Robert P.; Fulpius, Bernard W.; Cooper, David; Smith, Michael D.; Reich, E.; Possani, Lourival D.

doi:10.1016/s0021-9258(19)43428-5

Cited by 229 publications

(35 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Amino acid analysis was determined and was identical with that reported by Karlsson et al (1971). The binding constant (Xfd = 0.3 nM) and the toxin's toxicity in mice (LD^= 1.4 Mg) were determined and were found to be in good agreement with values previously reported (Karlsson et al, 1971;Klett et al, 1973).…”

Section: Methodssupporting

confidence: 82%

See 1 more Smart Citation

Synthesis and characterization of a heterobifunctional mercurial crosslinking agent: incorporation into cobratoxin and interaction with the nicotinic acetylcholine receptor

Wohlfeil¹,

Hudson²

1991

Biochemistry

View full text Add to dashboard Cite

The heterobifunctional organomercurial reagents 3-(acetoxymercurio)- and 3-(chloromercurio)-5-nitrosalicylaldehyde were prepared, characterized in model studies, and used to probe the interaction between cobratoxin, purified from the venom of the Thailand cobra (Naja naja siamensis), and the affinity-purified nicotinic acetylcholine receptor (AcChR) from Torpedo california electroplax. These reagents may also be useful in introducing chemically well-defined heavy metal atoms into proteins containing no reactive thiols. Model reagent adducts were prepared in situ by reductive amination with N-butylamine and N alpha-acetyllysine-N-methylamide. The nitrophenolic pKaS of the amine adducts were similar to those of the aldehyde reagents through reduced by 1.3-1.5 units when compared with the hydroxylmethyl reduction product. Reaction of either mercuriosalicylaldehyde with cobratoxin led to a single major modification product incorporating 1 mol of the reagent into cobratoxin at Lys 23. The Lys 23 modified toxin had a reduced binding affinity for the AcChR over that of the native toxin (Kd 2.75 nM cf. 0.3 nM). Reduction of the purified AcChR with 1 mM dithiothreitol (DTT) followed by removal of excess thiol led to cross-linking reactions with the Lys 23 modified cobratoxin to both the alpha and beta subunits of the AcChR complex. Reaction of DTT-treated AcChR with N-ethylmaleimide (NEM) blocked cross-linking, while treatment of the initially cross-linked toxin-AcChR complex with mercaptoethanol leads to reversal of cross-linking. These observations strongly support cross-linking mediated by the formation of a mercury-sulfur bond and further lend support the identity of the respective interacting sites in AcChR and toxin.

show abstract

Section: Methodssupporting

confidence: 82%

“…Some AcChR preparations were concentrated on Bio-Gel HTP hydroxyapatite. Triton X-100 solubilized and purified AcChR was analyzed by the method of Klett et al (1973) or Schmidt and Raftery (1973). The separation of AcChR from acetylcholine esterase was followed by the method of Ellman (1961).…”

Section: Methodsmentioning

confidence: 99%

Synthesis and characterization of a heterobifunctional mercurial crosslinking agent: incorporation into cobratoxin and interaction with the nicotinic acetylcholine receptor

Wohlfeil¹,

Hudson²

1991

Biochemistry

View full text Add to dashboard Cite

show abstract

“…The highest obtained from , and Electrophones is generally in the region of 6.5-7.5 pmol/g, and this corresponds to an uncorrected molecular mass for the protein of about 130000-150000 per toxin binding site (Olsen al. 1972;Klett et al 1973;Patrick, Lindstrom, Culp & M cM illan 1973;Green et al, unpublished). If this specific activity is taken as a working base, then each gram of tissue contains about 0.14 mg of receptor protein and a purification of 20-fold is required from the solubilized extract.…”

Section: Isolation Of Receptors From Torpedo Marmoratamentioning

confidence: 99%

“…In this technique, a material having a known affinity for the receptor is covalently attached to an insoluble support, usually a cross-linked agarose derivative. The materials which have been so attached are agonists and antagonists of acetylcholine action and include curare, reversible toxins similar to a-bungarotoxin, and quaternary ammonium compounds (Olsen, Meunier & Ghangeux 1972;Karlsson, Heilbronn & Widlund 1972;Schmidt & Raftery 1972;Biesecker 1973;Karlin & Gowburn 1973;Klett et al 1973;Green et al unpublished).…”

Section: Isolation Of Receptors From Torpedo Marmoratamentioning

confidence: 99%

Acetylcholine receptors

Green¹,

Miledi²,

Mora³

et al. 1975

Phil. Trans. R. Soc. Lond. B

View full text Add to dashboard Cite

Alpha-Bungarotoxin is one of a class of proteins, isolated from snake venoms, which antagonize the action of acetylcholine at vertebrate neuromuscular junctions and 'electroplaques' of electric fish. Alpha-Bungarotoxin blocks acetylcholine action irreversibly and may be labelled with either 125I or 3H. This irreversible binding is used as the basis of an in vitro assay for acetylcholine receptors, whether in intact tissue, membrane fragments or solubilized preparations. Acetylcholine receptors from Torpedo and denervated skeletal muscle have been solutilized and substantially purified using affinity chromatography. The distribution of acetylcholine receptors in several tissues has been determined, and an auto-immune response, induced by injection of purified Torpedo receptors, has been studied.

show abstract

“…Introduction cr-Bungarotoxin (a-BGT), a protein with a molecular weight of 8000, binds with high specificity to the acetylcholine nicotinic receptors of striated muscle [l-3] , electroplax [4] and brain [5]. Several neurotoxins such as a-BGT have been used as tools to localize [6], purify [7] and assay [8] for these receptors. Changeux [4] stated that (u-BGT has no effect on the kinetic parameters of acetylcholinesterase (Acetylcholine acetyl-hydrolase EC 3.1.1.7) obtained from the electric eel Electrophorus electricus, but no experimental results supporting this contention have thus far been presented.…”

mentioning

confidence: 99%