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)

OBJECTIVES - Relaxin induces the matrix metalloproteinase MMP-1 (collagenase-1) in TMJ fibrocartilaginous cells, and this response is potentiated by beta-estradiol. We identified the MMP-1 promoter sites and transcription factors that are induced by relaxin with or without beta-estradiol in fibrocartilaginous cells. MATERIAL AND METHODS - Early passage cells were transiently transfected with the pBLCAT2 plasmid containing specific segments of the human MMP-1 promoter regulating the chloramphenicol acyl transferase (CAT) gene and co-transfected with a plasmid containing the beta-galactosidase gene. The cells were cultured in serum-free medium alone or medium containing 0.1 ng/ml relaxin, or 20 ng/ml beta-estradiol or both hormones, and lysates assayed for CAT and beta-galactosidase activity. RESULTS - Cells transfected with the -1200/-42 or -139/-42 bp MMP-1 promoter-reporter constructs showed 1.5-fold and 3-fold induction of CAT by relaxin in the absence or presence of beta-estradiol, respectively. Relaxin failed to induce CAT in the absence of the -137/-69 region of the MMP-1 promoter, which contains the AP-1-and PEA3-binding sites. Using wild type or mutated minimal AP-1 and PEA-3 promoters we found that both these promoter sites are essential for the induction of MMP-1 by relaxin. The mRNAs for transcription factors c-fos and c-jun, which together form the AP-1 heterodimer, and Ets-1 that modulates the PEA-3 site, were upregulated by relaxin or beta-estradiol plus relaxin. CONCLUSION - These studies show that both the AP-1 and PEA-3 promoter sites are necessary for the induction of MMP-1 by relaxin in fibrocartilaginous cells.
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PMID:Induction of MMP-1 (collagenase-1) by relaxin in fibrocartilaginous cells requires both the AP-1 and PEA-3 promoter sites. 1962 19

c-Fos is a member of the activator protein 1 family that regulates transcription of target genes. c-Fos is transiently induced in specific regions of the brain after a variety of external stimuli including learning and memory formation. Analysis of gene expression in c-Fos-expressing cells of the brain may help identify target genes that play important roles in synaptic strength or neuronal morphology. In the present study, we developed a combined method of laser capture microdissection and 5-bromo-4-chloro-3-indoly-beta-D-galactopyranosidase (X-Gal) histology to analyze gene expression in stimulus-induced c-Fos-positive cells. Using transgenic mice carrying a c-fos-lacZ fusion gene, c-Fos-positive cells were easily identified by measuring of beta-galactosidase (beta-Gal) activity. To establish the fidelity of the reporter transgene, the time course of endogenous c-Fos and the c-fos-lacZ transgene expression in the amygdala induced by LiCl administration was investigated by immunohistochemistry and X-Gal staining. LiCl increased the numbers of c-Fos- and beta-Gal-positive cells in the central and basolateral amygdala of the transgenic mice. To ensure that RNA was preserved in X-Gal stained tissue sections, different fixations were examined, with the conclusion that ethanol fixation was best for both RNA preservation and X-Gal staining quality. Finally, in combining X-Gal staining, single-cell LCM and RT-PCR, we confirmed mRNA expression of endogenous c-fos and beta-actin genes in LiCl-induced beta-Gal-positive cells in the CeA, cortex and hippocampus. Combining LCM and transgenic reporter genes provides a powerful tool with which to investigate tissue- or cell-specific gene expression.
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PMID:A combined method of laser capture microdissection and X-Gal histology to analyze gene expression in c-Fos-specific neurons. 1992 27

There are sex differences in the neurochemistry of brainstem nuclei that participate in the control of breathing as well as sex differences in respiratory responses to hypoxia. Central chemoreception refers to the detection within the brain of minute changes in carbon dioxide (CO(2)) levels and the subsequent modulation of breathing. Putative central chemoreceptor sites are widespread and include cells located near the ventral surface of the brainstem in the retrotrapezoid nucleus (RTN), in the medullary midline raphe nuclei, and, more dorsally in the medulla, in the nucleus of the solitary tract and in the locus caeruleus at the pontomedullary junction as well as in the fastigial nucleus of the cerebellum. In this study, we ask if the cells that respond to CO(2) differ between the sexes. We used a transgenic mouse with a c-fos promoter driven tau-lacZ reporter construct (FTL) to map the locations of cells in the mouse brainstem and cerebellum that responded to exposure of mice of both sexes to 5% CO(2) or room air (control). X-gal (5-bromo-4-chloro-3-indolyl-beta-d-galactopyranoside) histochemical staining to detect the beta-galactosidase enzyme produced staining in the brains of mice of both sexes in all of the previously identified putative chemoreceptor sites, with the exception of the fastigial nucleus. Notably, the male RTN region contained significantly more x-gal-labeled cells than the female RTN region. In addition to new observations regarding potential sex differences in the retrotrapezoid region, we found the FTL mouse to be a useful tool for identifying cells that respond to the exposure of the whole animal to relatively low concentrations of CO(2).
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PMID:Fos-Tau-LacZ mice reveal sex differences in brainstem c-fos activation in response to mild carbon dioxide exposure. 1993 90


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