Cloning and expression of a human kidney cDNA for an alpha 2-adrenergic receptor subtype.

TLDR

The cloned receptor can be expressed in mammalian cells without other adrenergic subtypes, enabling the development of more selective alpha‑adrenergic ligands. The authors cloned an alpha‑2 adrenergic receptor subtype from a human kidney cDNA library using the platelet receptor gene as a probe, expressed the cDNA in COS‑7 cells, and demonstrated ligand binding with [³H]rauwolscine. The receptor’s amino‑acid sequence matches the platelet alpha‑2A receptor and conforms to GPCR family structure; competition curves identify it as the alpha‑2B subtype, whose gene is located on chromosome 4, distinct from the alpha‑2A gene on chromosome 10.

Abstract

An alpha 2-adrenergic receptor subtype has been cloned from a human kidney cDNA library using the gene for the human platelet alpha 2-adrenergic receptor as a probe. The deduced amino acid sequence resembles the human platelet alpha 2-adrenergic receptor and is consistent with the structure of other members of the family of guanine nucleotide-binding protein-coupled receptors. The cDNA was expressed in a mammalian cell line (COS-7), and the alpha 2-adrenergic ligand [3H]rauwolscine was bound. Competition curve analysis with a variety of adrenergic ligands suggests that this cDNA clone represents the alpha 2B-adrenergic receptor. The gene for this receptor is on human chromosome 4, whereas the gene for the human platelet alpha 2-adrenergic receptor (alpha 2A) lies on chromosome 10. This ability to express the receptor in mammalian cells, free of other adrenergic receptor subtypes, should help in developing more selective alpha-adrenergic ligands.