A. Lindsay et al., Induction of steroid 21-hydroxylase/beta-galactosidase transgene expression by unilateral adrenalectomy, ENDOCRINE R, 24(3-4), 1998, pp. 581-585
Unilateral adrenalectomy was used to induce compensatory growth in the cont
ralateral adrenal gland of transgenic mice bearing a steroid 21-hydroxylase
promoter/beta-galactosidase reporter (21-OHase/beta-gal) transgene, in whi
ch 6.4 kb of 5'-flanking sequence of the mouse steroid 21-OHase A gene are
linked to a LacZ reporter gene. 48 hours following removal of the right adr
enal gland, the left gland of transgene-positive mice showed a 4.5 fold inc
rease in specific activity of the beta-gal reporter, compared to the right
gland, while left glands from sham-operated transgene-positive and unilater
al adrenalectomized transgene-negative mice showed no such increase. The in
creased specific transgene reporter activity, relative to total adrenal gla
nd protein, must result from up-regulation of transgene expression, rather
than from the compensatory increase in adrenocortical mass. This suggests t
hat elements regulating trophic hormone-mediated 21-OHase gene expression i
n vivo are located within 6.4 kb of the 21-OHase gene transcription start s
ite.