Open AccessAn acetylcholine receptor precursor alpha subunit that binds alpha-bungarotoxin but not d-tubocurare.
Author(s) -
B E Carlin,
John C. Lawrence,
Jon Lindstrom,
John P. Merlie
Publication year - 1986
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.83.2.498
Subject(s) - interleukin 10 receptor, alpha subunit , interleukin 5 receptor alpha subunit , acetylcholine receptor , cys loop receptors , g alpha subunit , protein subunit , interleukin 12 receptor, beta 1 subunit , gamma aminobutyric acid receptor subunit alpha 1 , receptor , biochemistry , alpha (finance) , biology , chemistry , microbiology and biotechnology , nicotinic acetylcholine receptor , medicine , construct validity , nursing , gene , patient satisfaction
We have identified an intracellular form of the alpha subunit of the acetylcholine receptor that binds alpha-bungarotoxin with high affinity. Unlike the mature receptor complex, an alpha 2 beta gamma delta pentamer that migrates as a 9S species in velocity sedimentation analysis, the intracellular species moves as a 5S component. The kinetics of appearance of alpha subunit in the 5S component and the mature receptor complex indicate that the intracellular 5S component is a precursor of the mature receptor. The precursor species differs from 9S receptor in two critical features: (i) the precursor alpha subunit is not associated with beta subunit and (ii) alpha-bungarotoxin binding to the precursor alpha subunit is not inhibited by the cholinergic ligands decamethonium or d-tubocurarine. The properties of the precursor suggest that the acquisition of the ligand binding site by alpha subunit occurs at a distinct stage in the posttranslational development of functional acetylcholine receptor.