Beta-adrenergic receptor subtype is an intrinsic property of the receptor gene product

The gene encoding the hamster beta-adrenergic receptor (beta AR) was expressed in mouse C6 glioma cells, a cell line which normally expressed the beta 1 subtype of the receptor. Upon transfection with the hamster beta AR gene, the cells expressed increased levels of beta AR, as assessed both by protein immunoblotting and by the binding of the radiolabeled antagonist 125I-cyanopindolol. This newly expressed receptor was of the beta 2 subtype, as determined with a variety of agonists and antagonists. These results suggest that the subtype of the beta AR is an intrinsic property of the gene product and is not the result of a post-translational modification of the receptor by the cell in which it is expressed.