Profile of the Continuous Antigenic Regions on the Extracellular Part of the α Chain of an Acetylcholine Receptor

• Published in: Proceedings of the National Academy of Sciences - PNAS 1987-06, Vol.84 (11), p.3633-3637
• Main Authors: MULAC-JERICEVIC, B, KURISAKI, J, ATASSI, M. Z
• Format: Article
• Language: English
• Subjects: acetylcholine; Adsorbents; Animals; Antibodies; Antigen-Antibody Complex; Antiserum; Biochemistry; Biological and medical sciences; Cell Membrane - metabolism; Cell physiology; Electric Organ - metabolism; electric organs; Epitopes - analysis; Fundamental and applied biological sciences. Psychology; Immune Sera; Immunodominant epitopes; Macromolecular Substances; Molecular and cellular biology; Neurotransmission; Receptors; Receptors, Cholinergic - immunology; Receptors, Cholinergic - isolation & purification; Titration; Torpedo; Torpedo californica; Toxins; Ungulates; Washing
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.84.11.3633

Reaction of overlapping synthetic peptides spanning the extracellular part (residues 1-210) of the α chain of the Torpedo californica acetylcholine receptor (an α2β γ δ pentamer) with anti-receptor antibodies produced the profiles of the continuous antigenic regions of the correlate segment. Essentially similar profiles were recognized by rabbit and outbred mouse antibodies against isolated receptor or mouse antibodies against membrane-bound receptor. The antigenic sites reside within eight continuous regions: residues 1-14, 25-36, 41-53, 63-75, 102-114, 128-138, 172-182, and 188-198. Five of these regions (the second and the fifth through the eighth) appeared to be immunodominant. Significantly, two of these antigenic regions (i.e., those residing within residues 128-138 and 188-198) coincided with known toxin-binding regions. The antigenic profile suggests that recognition is directed to the intact molecule and only very slightly to the processed (fragmented) protein.