Ubiquitous transcription factors NF1 and Sp1 are involved in the androgen activation of the mouse vas deferens protein promoter.

Transcription of the mouse vas deferens protein (MVDP) gene is stimulated by androgens and we have previously shown that in a 162 bp fragment, located at position -121 to +41, a TGAAGTtccTGTTCT sequence functions as an androgen-dependent enhancer. To determine which factors are involved in the hormonally regulated MVDP gene transcription, we have used DNase I footprinting and band-shift assays to examine in vitro binding of proteins to the enhancer and promoter sequences and have determined the functional significance of the recognized DNA sequences in transient transfection assays. Studies using recombinant proteins such as the DNA binding domain of the androgen receptor (AR-DBD) and Sp1, and crude cellular extracts from T47D and vas deferens epithelial cells (VDEC) showed that in addition to AR-DBD, the transcriptional activators NF1 and Sp1 interact with the -121/+41 fragment in a specific manner. Transient transfection assays revealed that site-directed mutations in the NF1 and Sp1 binding elements strongly reduced (NF1) or abolished (Sp1) androgen induced expression. The results demonstrate that the -121/+41 sequence is a composite site for the androgen receptor mediated transactivation of the MVDP gene.

Tissue and species specificity of mouse ductus deferens protein.

The ductus deferens of the mouse contains a major protein with a molecular weight of 34.5 kd called mouse vas deferens protein (MVDP). Immunofluorescence histochemistry and immunoblotting with monoclonal antibodies have been used to investigate the localization, tissue, and species distribution, androgen-regulation, and developmental expression of this protein. Consistent positive immunoreaction was achieved in the ductus deferens epithelium, and immunofluorescence revealed that spermatozoa from the deferent duct were coated with MVDP. Western blot analysis showed the organ specificity of MVDP, which could not be detected in several organs in the mouse. Furthermore, MVDP appeared to be species specific since the proteins extracted from the ductus deferens of man, rat, guinea-pig, rabbit, and hamster did not react with the anti-MVDP probe. MVDP, whose expression is regulated by testosterone, was detectable at 20 days of age and its concentration increased rapidly from 20-30 days.

[Radioimmunoassay of testosterone in late fetal and newborn rabbit plasma, gonads and adrenal glands]. / Dosage radioimmunologique de la testostérone dans de plasma, les gonades et les surrénales de foetus en fin de gestation et de nouveau-nés, chez le lapin

A radioimmunoassay was used for measuring testosterone in the plasma, gonads and adrenals of 28, 29, 30 and 31-day-old rabbit fetuses of both sexes and newborns. A marked sex difference was shown in the concentrations of testosterone in plasma and in gonads whereas in adrenals the levels of testosterone were low in both sexes (34 to 147 pg/10 mg). In male fetuses, plasma testosterone levels increased from the 28th (133 +/- 20 pg/ml) to the 31st day (361 +/- 119 pg/ml) of intrauterine life, reaching then the values observed in the newborns (387 +/- 73 pg/ml). Plasma from males, on the other hand contained, at all stages studied, significantly more testosterone than plasma from female fetuses (21 +/- 6 to 41 +/- 11 pg/ml) and female newborns (42 +/- 6 pg/ml). In the same way, fetal testicular testosterone concentrations varying from 1 382 +/- 218 to 2 317 +/- 333 pg/10 mg were similar to those measured in the newborns (1 940 +/- 304 pg/10 mg) and significantly higher than fetal (13 to 34 pg/10 mg) or neonatal (44 pg/10 mg) ovarian concentrations. These results showed at evidence the endocrine activity of the fetal testis during this period.