Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.23 (beta-galactosidase)
 14,648 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This study was directed toward initial comparison and characterization of the activities of the human steroid 21-hydroxylase gene (CYP21) and pseudogene (CYP21P) promoters. DNA fragments containing the promoter regions of CYP21 and CYP21P were amplified and cloned into promoterless luciferase reporter plasmids either containing or lacking an enhancer element. Cells of the nonsteroidogenic COS-1 cell line, and the steroidogenic Y-1 cell line were transiently transfected with these recombinant plasmids and a beta-galactosidase cotransfection control plasmid. Cellular lysates were analyzed for luciferase and beta-galactosidase activities. In the nonsteroidogenic system, transfectants with either the CYP21 or CYP21P upstream sequence in enhancer containing plasmids showed a 2.3 fold increase (p < .001) in light production over controls. In the steroidogenic Y-1 cell system, these same CYp21 and CYP21P transfectants showed a 14.3 (+/- 0.8) and 5.2 (+/- 0.6) fold increase in luciferase activity respectively (p < .001) Transfections with recombinant reporter plasmids lacking an enhancer produced light emission which was not significantly different than controls. These observations indicate that 1.) one or more of the 35 nucleotide differences between the CYP21 and CYP21P upstream regions alters a DNA recognition site important for transcriptional activation of this gene in steroidogenic cells, 2.) the steroidogenic milieu has a stimulatory effect on both CYP21 and CYP21P promoter activities, and 3.) based on the minimal promoter activity observed in either cell type transfected with constructs lacking an enhancer element, both of these promoter sequences are enhancer dependent under constitutive conditions in both steroidogenic and nonsteroidogenic cells.
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PMID:Constitutive human steroid 21-hydroxylase promoter gene and pseudogene activity in steroidogenic and nonsteroidogenic cells with the luciferase gene as a reporter. 858 28

The 5'-flanking regions of genes for three mouse adrenal steroid hydroxylases were analyzed for their ability to direct adrenal cortex-specific beta-galactosidase (beta-gal) reporter expression both in cell culture and transgenic mice. The 5'-flanking regions chosen were from the genes for steroid 21-hydroxylase (21-OHase), expressed throughout the adrenal cortex and mediating both glucocorticoid and mineralocorticoid synthesis, and aldosterone synthetase (AS) and steroid 11 beta-hydroxylase (11 beta-OHase), which catalyze respectively the terminal steps of mineralocorticoid synthesis in the zona glomerulosa and glucocorticoid synthesis in the zona fasciculata/reticularis. While 5.0 kb of 11 beta-OHase gene 5'-flanking region and 5.4 kb of the AS gene 5'-flanking region mediated respectively moderate and low levels of beta-gal reporter expression in Y1 adrenocortical tumor cells, neither of these 5'-flanking regions was able to direct reporter expression to the appropriate adrenocortical zone of transgenic mice. This suggests that additional regulatory elements, lying outside these 5'-flanking regions, are required for 11 beta-OHase and AS gene expression in the intact mouse. In contrast, 6.4 kb of the mouse 21-OHase A gene 5' flanking region was able to direct specific beta-galactosidase reporter expression, in both Y1 cells and transgenic mice, indicating that elements directing adrenal cortex-specific gene expression in vivo are located not more than 6.4 kb 5' of the 21-OHase gene transcription start site.
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PMID:Adrenocortical-specific transgene expression directed by steroid hydroxylase gene promoters. 896 22

Unilateral adrenalectomy was used to induce compensatory growth in the contralateral adrenal gland of transgenic mice bearing a steroid 21-hydroxylase promoter/beta-galactosidase reporter (21-OHase/beta-gal) transgene, in which 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 adrenal gland, the left gland of transgene-positive mice showed a 4.5 fold increase in specific activity of the beta-gal reporter, compared to the right gland, while left glands from sham-operated transgene-positive and unilateral adrenalectomized transgene-negative mice showed no such increase. The increased specific transgene reporter activity, relative to total adrenal gland protein, must result from up-regulation of transgene expression, rather than from the compensatory increase in adrenocortical mass. This suggests that elements regulating trophic hormone-mediated 21-OHase gene expression in vivo are located within 6.4 kb of the 21-OHase gene transcription start site.
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PMID:Induction of steroid 21-hydroxylase/beta-galactosidase transgene expression by unilateral adrenalectomy. 988 41

Staining for beta-galactosidase (beta-gal) reporter activity in adrenal glands from adult, fetal and neonatal 21-OH/LacZ transgenic mice revealed mosaic patch patterns that were qualitatively similar to those seen in LacZ <--> wild-type mouse chimeras, at similar developmental stages. This suggests that, as in chimeras, the transgenic patch pattern may reflect cell lineage relationships. Consequently, 21-OH/LacZ transgenic mice could be useful as a simpler alternative to chimeras for the analysis of clonal growth and cell mixing during adrenocortical organogenesis. Embryonic day 16.5 (E16.5) adrenal cortices of 21-OH/LacZ transgenic mice displayed a punctate patch pattern, but by E18.5 "stripes" appeared to be emerging and were clearly visible by the day of birth (P0) and three days later (P3), consistent with the adult mosaic striped pattern. This suggests that adrenocortical organogenesis involves an initial period of randomly oriented clonal growth, followed by directional growth which begins in the perinatal period.
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PMID:Mosaic patch patterns in chimeric and transgenic mice suggest that directional growth in the adrenal cortex begins in the perinatal period. 1253 Jun 79

Mosaic beta-galactosidase reporter staining patterns in the adult adrenal cortex of 21-OH/LacZ transgenic mice were compared to those observed in mouse chimeras and X-inactivation mosaics, which are known to have a lineage basis. This revealed similar patterns of blue and white radial stripes in all three experimental groups. Each blue stripe may contain one or more blue coherent clones of cells but this was taken into account by correcting the observed stripe numbers for the effects of different proportions of LacZ-positive (blue) and LacZ-negative (unstained) cells between adrenals. The corrected stripe numbers were similar in all three experimental groups, which supports the hypothesis that the stripes in the adrenals of 21-OH/LacZ transgenic mice are formed in a similar way to those in chimeras and X-inactivation mosaics (i.e., they have a lineage basis). This suggests that the 21-OH/LacZ transgenic mouse is likely to be a valid model for studying steroidogenic cell lineage in the adrenal cortex, thereby providing additional support for the centripetal migration hypothesis of adrenocortical cytogenesis.
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PMID:Validity of the 21-OH/LacZ transgenic mouse as a model for studying adrenocortical cell lineage. 1566 82