Cell-free synthesis of acetylcholine receptor polypeptides

Messenger RNA coding for acetylcholine receptor peptides has been identified. This polyadenylate [poly(A)⁺]RNA from Torpedo californica directs, in a cell-free system, the synthesis of peptides 60,000, 51,000, 49,000 41,000, and 35,000 daltons which account for approximately 2 percent of the total synthesized proteins. The results suggest that several different messenger RNA's code for the receptor subunits. These proteins react specifically to antiserum to native acteylcholine receptor, suggesting that the primary translational product has conformational features similar to the native receptor. Further, the results support the idea that there is posttranslational modification of receptor subunits as the molecular weights of the cell-free synthesized proteins differ from those of purified receptor subunits.