Cloning, characterization and expression of a functional mouse ACTH receptor.

A polymerase chain reaction-generated mouse ACTH-R probe was used to screen a mouse genomic library, and a clone of 13kb containing the entire coding sequence was isolated. The coding sequence shows 84% homology with the human gene at the DNA level and encodes a peptide with 89% homology to the human ACTH-R. This gene is expressed as a major transcript of 1.8kb in the mouse adrenal gland. The gene was expressed in HeLa cells and cAMP production in response to either ACTH or alpha-MSH was measured. cAMP increased in an ACTH dose dependent manner suggesting an EC50 of 7 x 10(-10)M ACTH. alpha-MSH was without effect on this receptor. In conclusion we have cloned a mouse ACTH receptor gene and demonstrated for the first time its expression and functional effect in HeLa cells.