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)

The purpose of these studies was to explore the sex- and tissue-specific expression of the LH receptor (LHR) gene. Fusion genes containing three different lengths of the 5'-flanking region of the mouse LHR gene (7.4 kb, 2.1 kb, and 173 bp), beta-globin intron, and the beta-galactosidase (beta-GAL) reporter gene were constructed. Function of these fusion genes [LHR (7.4 kb)/beta-GAL, LHR (2.1 kb)/beta-GAL, and LHR (173 bp)/beta-GAL] was studied in vitro and in vivo. beta-GAL expression was higher in transfected mouse Leydig (mLTC-1) than in granulosa (KK-1) tumor cells with all three constructs. The shortest LHR (173 bp)/beta-GAL construct showed the highest level of beta-GAL expression in both cell types. beta-GAL expression was clearly suppressed with the 2.1-kb promoter and was nearly undetectable with the 7.4-kb construct. In transgenic mice, all three constructs directed beta-GAL expression to adult Leydig cells, displaying decreasing intensity with increasing promoter length. Unexpectedly, beta-GAL expression was also found in elongating spermatids, but not in fetal Leydig cells. There was no expression in any ovarian cell type with the three constructs used, except that one of five mouse lines with the LHR (7.4 kb)/beta-GAL construct expressed beta-GAL in their thecal cells. Two lines transgenic for the 7.4- and 2.1-kb promoter constructs each directed high beta-GAL expression to the brain, with higher intensity in 7.4-kb lines. All promoters directed expression to the pituitary gland, some faintly to the adrenal gland. Northern hybridization analysis of the beta-GAL transcripts in Leydig cells revealed that the 173-bp promoter mainly gave rise to the full-length beta-GAL messenger RNA, whereas the 2.1- and 7.4-kb promoters mainly induced transcription of truncated beta-GAL messages. This suggests that the 5'-flanking region, upstream of -173, determines the formation of splice variants of the structural gene to be transcribed. The present findings in transgenic mice provide in vivo evidence for basal transcriptional activity of the first 173 bp upstream of the LHR translation initiation codon. In conclusion, the promoter function of the mouse LHR 5'-flanking region is tissue, age, and sex specific. The sequence upstream of the basal promoter determines extragonadal LHR expression as well as the alternate splicing of its message. The promoter sequences directing LHR expression to fetal Leydig cells and ovary reside outside the 7.4-kb 5'-flanking region and remain to be identified.
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PMID:Promoter function of different lengths of the murine luteinizing hormone receptor gene 5'-flanking region in transfected gonadal cells and in transgenic mice. 1135 91

Five fish cell lines were tested for their ability to be transduced by Ac-CAlacZ, a recombinant baculovirus that is capable of expressing a beta-galactosidase reporter gene from the CAG promoter (consisting of a cytomegalovirus enhancer element, a chicken actin promoter and rabbit beta-globin termination sequences). TO (Tilapia ovary), EPC (carp), CHH-1 (Chum salmon heart fibroblast) and CHSE-214 (chinook salmon embryo) cells were transducible, as demonstrated by an in situ beta-galactosidase assay, whereas RTG-2 (rainbow trout gonad) cells were not. The EPC cell line was used for more detailed studies on baculovirus transduction. The transduction frequency was found to be higher at 28 degrees C than at 21 degrees C. Addition of the histone deacetylase inhibitor sodium butyrate increased the number of blue cells detected 5- to 7-fold. The m.o.i. was positively correlated with transduction frequency, although the relationship did not appear to be strictly linear, as has been observed with mammalian cells. The temperature at which baculoviruses were adsorbed to EPC cells did not affect levels of beta-galactosidase expression. We also examined expression levels of beta-galactosidase in EPC cells after infection with a baculovirus construct that overexpresses the vesicular stomatitis virus G protein and displays it on the virion surface. Expression levels with this virus were approximately 15-fold higher than were observed with Ac-CAlacZ.
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PMID:Transduction of cultured fish cells with recombinant baculoviruses. 1269 82

Previous work has demonstrated a more decondensed large-scale chromatin structure and a more internal nuclear position for gene-rich versus gene-poor chromosome regions. Here, we show that large-scale chromatin opening and changes in intranuclear positioning of chromosome regions can be induced by normal levels of endogenous transcription factors acting on mammalian regulatory sequences. We transfected mouse erythroleukemia cells with a 15 kbp plasmid containing a lac operator repeat plus beta-globin regulatory sequences driving a beta-galactosidase reporter gene. After green-fluorescent-protein/lac-repressor fusion-protein binding or after fluorescence in situ hybridization, the volume and location of the transgene array signal were measured. With both detection methods, we found that the volume was severalfold larger when transcription was on. While silent transgene arrays were located close to the nuclear membrane, we observed a significantly more internal position for the transcriptionally active state. Our results indicate that both large-scale chromatin decondensation and changes in nuclear positioning as observed for large, complex gene-rich chromosome regions can be reproduced by endogenous regulatory sequences acting within simple repetitive transgene arrays.
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PMID:Differential large-scale chromatin compaction and intranuclear positioning of transcribed versus non-transcribed transgene arrays containing beta-globin regulatory sequences. 1533 68

In the context of developing a safe genetic vaccination strategy we tested and studied globin-stabilized mRNA-based vaccination in mice. This vaccination strategy has the advantages of genetic vaccination (easy production, adaptability to any disease and inexpensive storage when lyophilized), but not the drawbacks of DNA vaccination (long-term uncontrolled expression of a transgene, possibility of integration into the host genome and possible induction of anti-DNA antibodies). We report here that injection of naked beta-globin untranslated region (UTR)-stabilized mRNA coding for beta-galactosidase is followed by detectable translation in vivo. In addition, we show that such a vaccination strategy primes a T helper 2 (Th2) type of response which can be enhanced and shifted to a Th1-type immune response by application of recombinant granulocyte/macrophage colony-stimulating factor 1 day after mRNA injection. Our data demonstrate that the administration of globin UTR-stabilized mRNA is a versatile vaccination strategy that can be manipulated to fit the requirement of antiviral, antibacterial or antitumor immunity.
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PMID:Polarization of immunity induced by direct injection of naked sequence-stabilized mRNA vaccines. 1537 10

Sry (sex-determining region on Y chromosome) is expressed in the undifferentiated, bipotential genital ridges of mammalian XY fetuses. The expression of Sry initiates testis development, but the lineage of Sry-expressing cells is unclear. In this study, double-transgenic mice were analyzed using the Cre/loxP system. Cre under the control of the Sry promoter was expressed in the fetal gonads of transgenic mice similarly to endogenous Sry. The Sry/Cre-transgenic mice were crossed with CAG(cytomegalovirus immediate-early enhancer, chicken beta-actin promoter and fusion intron of chicken beta-actin and rabbit beta-globin)/loxP/CAT/loxP/LacZ-transgenic mice, in which the transgene expressed beta-galactosidase after a Cre-mediated recombination event. Sertoli cells, germ cells of testes and granulosa cells of ovaries of double-transgenic mice stained positive with X-gal. Cre expression was detected in germ cells and peritubular/Sertoli cells in adult testes. It is not clear whether beta-galactosidase expression in the Sertoli cells of the testes occurred as a result of Cre expression in the adult or in the fetal gonads. These analyses indicate that cells expressing Sry-inducing factors in female fetal gonads become granulosa cells.
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PMID:Investigation of the fate of Sry-expressing cells using an in vivo Cre/loxP system. 1646 92


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