The molecular cloning and characterisation of cDNA coding for the α subunit of the acetyl-choline receptor

Abstract

A rare cDNA coding for most of the α subunit of the Torpedo nicotinic acetylcholine receptor has been cloned into bacteria. The use of a mismatched oligonucleotide primer of reverse trans-criptase facilitated the design of an efficient, specific probe for recombinant bacteria. DNA sequence analysis has enabled the elucidation of a large part of the polypeptide primary sequence which is discussed in relation to its acetylcholine binding activity and the location of receptor within the plasma membrane. When used as a radioactive probe, the cloned cDNA binds specifically to a single Torpedo mRNA species of about 235O nucleotides in length but fails to show significant cross-hybridisation with α subunit mRNA extracted from cat muscle.