The goals of this proposal are to understand the biochemical procedures by which at target organs and to provide a molecular basis for the clinical manipulation of abnormal growth of these organs. For the past three years, we have isolated and produced two very important tools [full-length of human/rat androgen receptor (AR) cDNAs and mono-/poly- specific antibodies to AR] for the study of molecular mechanism of androgen action. We also found several mutations of AR in patients with androgen insensitivity or testicular feminization (Tfm) syndrome. Based on these discoveries, we propose to test four hypotheses: Hypothesis I: Absent or defective AR may cause the Tfm syndrome. To test this hypothesis, we plan to sequence the coding region of AR gene from human and mice with Tfm syndrome. The results may allow us to detect the abnormal AR at DNA and RNA levels. Hypothesis II: Some defective AR may prevent the translocation of AR from cytoplasm to nuclei. To test this hypothesis, we plan to apply the immunocytology with microwave-fixed method to locate AR in cultured fibroblasts from Tfm patients. The results of hypotheses I and II may allow us to determine the sequences contributing to the nuclear localization process for the AR. Hypothesis III: The prostatic glands from Tfm mice may be reinduced and developed by introduction of normal AR cDNA into the urogenital sinus (UGS) of Tfm mice. To test this hypothesis, the UGS from Tfm mice will be transfected with retrovirus containing normal AR cDNA and cultured in vivo to be examined whether prostatic glands are induced. The results may demonstrate the necessary of normal AR in the mesenchyme (stroma) for the prostate development. Hypothesis IV: The Tfm syndrome in mice may be corrected by zygote microinjection (transgenic experiment) of normal AR cDNA. To test this hypothesis, the normal AR cDNA will be cloned into expression vector containing a very strong promoter (elongation factor promoter) and microinjected into the zygote of Tfm mice. The results may provide the possibility of gene therapy for the Tfm syndrome. The above studies will permit an evaluation of the role of AR in Tfm syndrome and may eventually lead to the development of new diagnostic methods and new ideas in clinical treatment of Tfm syndrome.