CLONING AND EXPRESSION OF THE ALPHA(2C)-ADRENERGIC RECEPTOR FROM THE OK CELL-LINE

The alpha(2)-adrenergic receptors have been divided into four pharmaco logical subtypes, alpha(2A), alpha(2B), alpha(2C), and alpha(2D). The OK cell line, a cell line derived from an opossum kidney, expresses th e alpha(2C)-adrenergic receptor and is the prototypical cell line for the alpha(2C) receptor subtype. The cloned human alpha(2C)-C4 and rat RG10 receptors have been shown to express alpha(2C) pharmacology. Here we report the cloning and expression of the OK alpha(2C)-adrenergic r eceptor, OKc2. The receptor has 64% deduced amino acid identity and 21 % similarity to the alpha(2)-C4 receptor, giving an overall similarity of 85%. The clone, expressed in Chinese hamster ovary cells, has a ph armacology that correlates very well (r = 0.97) with that of the nativ e OK cell alpha(2C)-adrenergic receptor, and it is negatively coupled to adenylyl cyclase.