Action of the e locus of mice in the response of phaeomelanic hair follicles to alpha-melanocyte-stimulating hormone in vitro.

Dibutyryl adenosine 3',5'-monophosphate (dibutyryl cyclic AMP) induced eumelanin synthesis in hair bulb melanocytes of recessive yellow (e/e) mice in vitro, whereas alpha-melanocyte-stimulating hormone (alpha-MSH) did not. In contrast, the melanocytes of lethal yellow (Ay/a) mice produced eumelanin in response to both dibutyryl cyclic AMP and alpha-MSH. These results suggest that the e locus controls a mechanism that determines the function of an alpha-MSH receptor.