The beta 1-adrenergic receptor of the turkey erythrocyte. Molecular heterogeneity revealed by purification and photoaffinity labeling.

Determination of the molecular size of frog and turkey erythrocyte .beta.-adrenergic receptors by radiation inactivation

“…Photoaffinity labeling using 12iI-labeled (p-azidobenzyl)carazolol of similar preparations or particulate receptor also resulted in the visualization of these two bands (Figure 4B), which were specifically labeled with a classic /3|-adrenergic specificity [see Figure 4B and Shorr et al (1982b)]. As described elsewhere (Shorr et al, 1982b), each of these proteins has recently been purified to homogeneity and shown to possess binding properties characteristic of ^[-adrenergic receptors. The presence of these two populations of binding sites in the membranes, however, did not result in a biphasic irradiation curve (Figure 3B).…”

“…Data were analyzed by computer-based methods as described by De Lean et al (1982). (Bottom panel) Data similar to those shown in the top panel but obtained by using receptor (3 pM) solubilized from the membrane with digitonin and purified to apparent homogeneity by sequential affinity and high-performance liquid chromatography as described previously (Shorr et al, 1982b). Samples contained 3-4 mg/mL BSA to minimize receptor losses on the glass vial surface during irradiation.…”

“…described by Shorr et al (1982a). Purified /Spadrenergic receptors were prepared by essentially similar methods as described by Shorr et al (1982b). Characterization of purified preparations by radioiodination, isoelectric focusing, and SDS-PAGE was also as described previously (Shorr et al, 1982a,b).…”

“…Ligand Binding Assays. Soluble receptor assays using 125I-labeled (+)-and (-)-cyanopindolol were performed as described in Shorr et al (1982b). The separation of bound from free ligand was accomplished by chromatography on Sephadex G-50.…”

Mammalian .beta.2-adrenergic receptor: reconstitution of functional interactions between pure receptor and pure stimulatory nucleotide binding protein of the adenylate cyclase system

“…To date, two of these three components have been purified to apparent homogeneity. The 3-adrenergic receptor binding proteins have been purified from frog erythrocytes (Shorr et al, 1982a) and turkey erythrocytes (Shorr et al, 1982b), as well as from the lungs of several mammalian species (Benovic et al, 1984;Homey et al, 1982). The purified receptors from amphibian and mammalian species are single polypeptides that both bind ligands with appropriate specificity and are capable of conveying adrenergic responsiveness to cells that contain Ns and adenylate cyclase but no endogenous receptors (Cerione et al, 1983a).…”