α and β subunits of the nicotinic acetylcholine receptor contain covalently bound lipid

Labeling of the BC₃H1 muscle-like cell line with [³H]palmitate, followed by immunoprecipitation of the acetylcholine receptor, indicated that the α and β subunits of the receptor contain covalently bound fatty acid. After acid hydrolysis, fatty acid methyl esters could be recovered from the isolated [³H]palmitate-labeled α subunit. Treatment of differentiated BC₃H1 cells with cerulenin, an inhibitor of fatty acid and sterol synthesis and fatty acid acylation of proteins, resulted in a 50% inhibition in expression of the acetylcholine receptor on the cell surface under conditions where there was minimal inhibition of protein synthesis. We conclude that this previously undetected post-translational modification may play a role in assembly and/or surface expression of the acetylcholine receptor.