EXPRESSION OF ANDROGEN RECEPTOR MESSENGER-RNA DURING MOUSE EMBRYOGENESIS

Androgen receptor (AR) is a member of the nuclear receptor superfamily which acts as a ligand-dependent transcription factor (Beato, M., Her rlich, P., Schutz, 1989. Steroid hormone receptors: many actors in sea rch of a plot. Cell 83, 851-857). It plays a pivotal role in sexual de velopment and reproduction (Wilson, J.D., Griffin, J.E., George, F.W., Leshin, M., 1981. The role of gonadal steroids in sexual differentiat ion. Rec. Frog. Horm. Res. 37, 1-39; Jest, A., 1990. Hormonal control of the masculinization of the body. In: Baulieu, E.E., Kelly, D.A., (E ds.), Hormones, from Molecules to Disease. Chapman and Hall, New York and London, pp. 439-442.). Mutations in the AR sequence cause a number of physiological disorders, such as partial and complete androgen ins ensitivity syndromes, that lead to abnormal sexual development (Patter son, M.N., McPhaul, M.J., Hughes, I.A., 1994. Androgen insensitivity s yndrome. Balliere's Clin. Endocrinol. Metab. 8, 379-404.). There an in dications that AR may also have other functions. For example, structur al alterations of the AR sequence have been implicated in prostate can cer (Visakorpi, T., Huytinen, E., Koivisto, P., Tanner, M., Keinanen, R., Palmberg, C., Palotie, A., Tammela, T., Isola, J., Kallioniemi, O. -P., 1995. In vivo amplification of the androgen receptor gene and pro gression of human prostate cancer. Nature Genet. 9, 401-406.) and in t he development of spinal and bulbar muscular atrophy, a neurodegenerat ive disease (Kennedy, W.R., Alter, M., Sung, J.H., 1968. Progressive p roximal spinal and bulbar muscular atrophy of late onset: a sex-linked recessive trait. Neurology 18, 671-680.). Here, we have investigated the spatial and temporal expression of AR during mouse organogenesis b y in situ hybridisation. We demonstrate that AR transcripts occur in t he developing external genitalia, pituitary, adrenals, kidneys and mus culus levator ani, in addition to the known expression sites in the Wo lffian ducts and its derivatives and during development of the mammary glands. (C) 1998 Elsevier Science Ireland Ltd.