Mullins J J, Sigmund C D, Kane-Haas C, Gross K W, McGowan R A
Department of Molecular and Cellular Biology, Roswell Park Memorial Institute, Buffalo, NY 14263.
EMBO J. 1989 Dec 20;8(13):4065-72. doi: 10.1002/j.1460-2075.1989.tb08590.x.
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.
为了进一步阐明小鼠Ren-2基因的组织特异性调控，尤其是其在肾上腺中的表达情况，我们已将DBA/2 Ren-2基因导入Ren-1c/Ren-1c小鼠的基因组中。在此，我们报告对Ren-2转基因小鼠的观察结果。发现该基因在正确的组织谱中表达，并且在下颌下腺中存在适当的激素调控。定量分析显示，转录水平相对于正常Ren-2表达既有正向变化（肾上腺和性附属组织）也有负向变化（下颌下腺和肾脏）。在DBA/2近交系小鼠中，雌性肾上腺中的表达在发情期于X区和束状带之间呈周期性变化。转基因在肾上腺内的表达仅限于X区。因此，这种表型是大多数双肾素基因小鼠品系的特征，与转基因来源的DBA/2品系中的表型不同。这表明DBA/2肾上腺中的细胞特异性表达至少由一个额外的基因座反式介导。我们证明，对转基因小鼠进行合适的遗传杂交可部分恢复周期性表型。
