Expression of the DBA/2J Ren-2 gene in the adrenal gland of transgenic mice.

To characterize further the tissue-specific control of the mouse Ren-2 gene, and in particular its expression in the adrenal gland, we have introduced the DBA/2 Ren-2 gene into the genome of Ren-1c/Ren-1c mice. Here we report our observations on Ren-2 transgenic mice. Expression was found in the correct spectrum of tissues and included appropriate hormonal control in the submandibular gland. Quantitatively transcript levels varied both positively (adrenal gland and sex-accessory tissue) and negatively (submandibular gland and kidney) with respect to normal Ren-2 expression. In the DBA/2 inbred mouse strain expression in the female adrenal gland cycles during oestrus between the X-zone and the zona fasciculata. Transgene expression within the adrenal gland was restricted to the X-zone. Therefore this phenotype, which is characteristic of most two-renin-gene strains of mice, contrasts with that found in the strain DBA/2 from which the transgene was derived. This suggests that cell-specific expression in the DBA/2 adrenal gland is mediated in trans by at least one additional locus. We demonstrate that suitable genetic crosses of the transgenic mice can partially restore the cycling phenotype.