Molecular dissection of cholinergic binding sites: how do snakes escape the effect of their own toxins?
Snakes have evolved a novel binding site demonstrating selective biorecognition. The snake nicotinic acetylcholine receptor is sensitive to acetylcholine while resistant to the effect of the lethal neurotoxins secreted in their own venom. By subjecting recombinant binding sites to point mutagenesis, biochemical analyses and NMR spectroscopy the binding characteristics of three cholinergic ligands have been measured. The amino acid residue at position 189 has been found to be of particular importance to toxin binding.
Ohana
B
B
Department of Cell Research and Immunology, Tel Aviv University, Israel.
Fraenkel
Y
Y
Navon
G
G
Gershoni
J M
JM
D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D002038:Bungarotoxins / Q000378:metabolism; D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D011978:Receptors, Nicotinic / Q000235:genetics / Q000378:metabolism*; D011994:Recombinant Proteins / Q000378:metabolism; D012689:Sequence Homology, Nucleic Acid; D012910:Snake Venoms / Q000633:toxicity*; D012911:Snakes / Q000502:physiology*; D014101:Torpedo / Q000502:physiology
D002038:Bungarotoxins; D011978:Receptors, Nicotinic; D011994:Recombinant Proteins; D012910:Snake Venoms