scholarly journals Role of the 5′ enhancer of the glutamine synthetase gene in its organ-specific expression

1997 ◽  
Vol 323 (3) ◽  
pp. 611-619 ◽  
Author(s):  
Heleen LIE-VENEMA ◽  
Piet A. J. DE BOER ◽  
Antoon F. M. MOORMAN ◽  
Wouter H. LAMERS

In mammals, glutamine synthetase (GS) is expressed in a large number of organs, but the precise regulation of its expression is still obscure. Therefore a detailed analysis of the activity of the upstream regulatory element of the GS gene in the transcriptional regulation of its expression was carried out in transgenic mice carrying the chloramphenicol acetyltransferase (CAT) gene under the control of the upstream regulatory region of the GS gene. CAT and GS mRNA expression were compared in liver, epididymis, lung, adipocytes, testis, kidney, skeletal muscle and gastrointestinal tract, both quantitatively by ribonuclease-protection analysis and topographically by in situ hybridization. It was found that the upstream regulatory region is active with respect both to the level and to the topography of GS gene expression in liver, epididymis, gastrointestinal tract (stomach, small intestine and colon) and skeletal muscle. On the other hand, in the kidney, brain, adipocytes, spleen, lung and testis, GS gene expression is not or only partly regulated by the 5´ enhancer. A second enhancer, identified within the first intron, may regulate GS expression in the latter organs. Furthermore, CAT expression in the brain did not co-localize with that of GS, showing that the 5´ regulatory region of the GS gene does not direct its expression to the astrocytes.

Development ◽  
1998 ◽  
Vol 125 (21) ◽  
pp. 4185-4193 ◽  
Author(s):  
Q. Gao ◽  
R. Finkelstein

The Bicoid (Bcd) morphogen establishes the head and thorax of the Drosophila embryo. Bcd activates the transcription of identified target genes in the thoracic segments, but its mechanism of action in the head remains poorly understood. It has been proposed that Bcd directly activates the cephalic gap genes, which are the first zygotic genes to be expressed in the head primordium. It has also been suggested that the affinity of Bcd-binding sites in the promoters of Bcd target genes determines the posterior extent of their expression (the Gene X model). However, both these hypotheses remain untested. Here, we show that a small regulatory region upstream of the cephalic gap gene orthodenticle (otd) is sufficient to recapitulate early otd expression in the head primordium. This region contains two control elements, each capable of driving otd-like expression. The first element has consensus Bcd target sites that bind Bcd in vitro and are necessary for head-specific expression. As predicted by the Gene X model, this element has a relatively low affinity for Bcd. Surprisingly, the second regulatory element has no Bcd sites. Instead, it contains a repeated sequence motif similar to a regulatory element found in the promoters of otd-related genes in vertebrates. Our study is the first demonstration that a cephalic gap gene is directly regulated by Bcd. However, it also shows that zygotic gene expression can be targeted to the head primordium without direct Bcd regulation.


1995 ◽  
Vol 15 (6) ◽  
pp. 3442-3449 ◽  
Author(s):  
M S Donoviel ◽  
N Kacherovsky ◽  
E T Young

The alcohol dehydrogenase 2 (ADH2) gene of Saccharomyces cerevisiae is under stringent glucose repression. Two cis-acting upstream activation sequences (UAS) that function synergistically in the derepression of ADH2 gene expression have been identified. UAS1 is the binding site for the transcriptional regulator Adr1p. UAS2 has been shown to be important for ADH2 expression and confers glucose-regulated, ADR1-independent activity to a heterologous reporter gene. An analysis of point mutations within UAS2, in the context of the entire ADH2 upstream regulatory region, showed that the specific sequence of UAS2 is important for efficient derepression of ADH2, as would be expected if UAS2 were the binding site for a transcriptional regulatory protein. In the context of the ADH2 upstream regulatory region, including UAS1, working in concert with the ADH2 basal promoter elements, UAS2-dependent gene activation was dependent on orientation, copy number, and helix phase. Multimerization of UAS2, or its presence in reversed orientation, resulted in a decrease in ADH2 expression. In contrast, UAS2-dependent expression of a reporter gene containing the ADH2 basal promoter and coding sequence was enhanced by multimerization of UAS2 and was independent of UAS2 orientation. The reduced expression caused by multimerization of UAS2 in the native promoter was observed only in the presence of ADR1. Inhibition of UAS2-dependent gene expression by Adr1p was also observed with a UAS2-dependent ADH2 reporter gene. This inhibition increased with ADR1 copy number and required the DNA-binding activity of Adr1p. Specific but low-affinity binding of Adr1p to UAS2 in vitro was demonstrated, suggesting that the inhibition of UAS2-dependent gene expression observed in vivo could be a direct effect due to Adr1p binding to UAS2.


2015 ◽  
Vol 55 (2) ◽  
pp. 159-168 ◽  
Author(s):  
Daniil V Popov ◽  
Evgeny A Lysenko ◽  
Tatiana F Vepkhvadze ◽  
Nadia S Kurochkina ◽  
Pavel A Maknovskii ◽  
...  

The goal of this study was to identify unknown transcription start sites of thePPARGC1A(PGC-1α) gene in human skeletal muscle and investigate the promoter-specific regulation ofPGC-1αgene expression in human skeletal muscle. Ten amateur endurance-trained athletes performed high- and low-intensity exercise sessions (70 min, 70% or 50%o2max). High-throughput RNA sequencing and exon–exon junction mapping were applied to analyse muscle samples obtained at rest and after exercise.PGC-1αpromoter-specific expression and activation of regulators of PGC-1α gene expression (AMPK, p38 MAPK, CaMKII, PKA and CREB1) after exercise were evaluated using qPCR and western blot. Our study has demonstrated that during post-exercise recovery, human skeletal muscle expresses thePGC-1αgene via two promoters only. As previously described, the additional exon 7a that contains a stop codon was found in all samples. Importantly, only minor levels of other splice site variants were found (and not in all samples). Constitutive expressionPGC-1αgene occurs via the canonical promoter, independent of exercise intensity and exercise-induced increase of AMPKThr172phosphorylation level. Expression ofPGC-1αgene via the alternative promoter is increased of two orders after exercise. This post-exercise expression is highly dependent on the intensity of exercise. There is an apparent association between expression via the alternative promoter and activation of CREB1.


2006 ◽  
Vol 5 (6) ◽  
pp. 935-944 ◽  
Author(s):  
Dana Gebhart ◽  
Adam K. Bahrami ◽  
Anita Sil

ABSTRACT Despite the existence of a number of genetic tools to study the fungal pathogen Histoplasma capsulatum, strategies for conditional gene expression have not been developed. We used microarray analysis to identify genes that are transcriptionally induced or repressed by the addition of copper sulfate (CuSO4) to H. capsulatum yeast cultures. One of these genes, CRP1, encodes a putative copper efflux pump that is significantly induced in the presence of CuSO4. The upstream regulatory region of CRP1 was sufficient to drive copper-regulated expression of two reporter genes, lacZ and the gene encoding green fluorescent protein. Microarray experiments were performed to determine a copper concentration that triggers accumulation of the CRP1 transcript without significant perturbation of global gene expression. These studies show that the CRP1 upstream regulatory region can be used for ectopic expression of heterologous genes in H. capsulatum. Furthermore, they demonstrate the strategic use of microarrays to identify conditional promoters that confer induction in the absence of large-scale shifts in gene expression.


1993 ◽  
Vol 13 (11) ◽  
pp. 6690-6701
Author(s):  
H Koizumi ◽  
M F Horta ◽  
B S Youn ◽  
K C Fu ◽  
B S Kwon ◽  
...  

The gene encoding the cytolytic protein perforin is selectively expressed by activated killer lymphocytes. To understand the mechanisms underlying the cell-type-specific expression of this gene, we have characterized the regulatory functions and the DNA-protein interactions of the 5'-flanking region of the mouse perforin gene (Pfp). A region extending from residues +62 through -141, which possesses the essential promoter activity, and regions further upstream, which are able to either enhance or suppress gene expression, were identified. The region between residues -411 and -566 was chosen for further characterization, since it contains an enhancer-like activity. We have identified a 32-mer sequence (residues -491 to -522) which appeared to be capable of enhancing gene expression in a killer cell-specific manner. Within this segment, a 9-mer motif (5'-ACAGGAAGT-3', residues -505 to -497; designated NF-P motif), which is highly homologous to the Ets proto-oncoprotein-binding site, was found to interact with two proteins, NF-P1 and NF-P2. NF-P2 appears to be induced by reagents known to up-regulate the perforin message level and is present exclusively in killer cells. Electrophoretic mobility shift assay and UV cross-linking experiments revealed that NF-P1 and NF-P2 may possess common DNA-binding subunits. However, the larger native molecular mass of NF-P1 suggests that NF-P1 contains an additional non-DNA-binding subunit(s). In view of the homology between the NF-P motif and other Ets proto-oncoprotein-binding sites, it is postulated that NF-P1 and NF-P2 belong to the Ets protein family. Results obtained from the binding competition assay, nevertheless, suggest that NF-P1 and NF-P2 are related to but distinct from Ets proteins, e.g., Ets-1, Ets-2, and NF-AT/Elf-1, known to be expressed in T cells.


Author(s):  
Andika Gunadi ◽  
◽  
Ning Zhang ◽  
John J. Finer ◽  
◽  
...  

Although most genome editing efforts focus on modifications to gene coding regions, this chapter emphasizes genome editing of the upstream regulatory regions. Thoughtful editing of the promoter region will ultimately lead to improved plants, modified for more precise control of the intensity and specificity of native gene expression. In this chapter, we present an overview of the promoter or upstream regulatory region of a gene, and describe how this sequence is defined and studied. We then describe how the composition and arrangements of cis-regulatory elements within the promoter and the leading intron associated with the promoter region have been studied using classical transgenic approaches to reveal what regulatory components might be suitable for genome editing approaches. Finally, we offer some suggestions for pursuit of promoter editing and gene expression modulation, which will eventually lead to modified plants with an altered regulation of native gene expression.


1993 ◽  
Vol 13 (2) ◽  
pp. 1264-1272 ◽  
Author(s):  
C K Vincent ◽  
A Gualberto ◽  
C V Patel ◽  
K Walsh

Regulatory sequences of the M isozyme of the creatine kinase (MCK) gene have been extensively mapped in skeletal muscle, but little is known about the sequences that control cardiac-specific expression. The promoter and enhancer sequences required for MCK gene expression were assayed by the direct injection of plasmid DNA constructs into adult rat cardiac and skeletal muscle. A 700-nucleotide fragment containing the enhancer and promoter of the rabbit MCK gene activated the expression of a downstream reporter gene in both muscle tissues. Deletion of the enhancer significantly decreased expression in skeletal muscle but had no detectable effect on expression in cardiac muscle. Further deletions revealed a CArG sequence motif at position -179 within the promoter that was essential for cardiac-specific expression. The CArG element of the MCK promoter bound to the recombinant serum response factor and YY1, transcription factors which control expression from structurally similar elements in the skeletal actin and c-fos promoters. MCK-CArG-binding activities that were similar or identical to serum response factor and YY1 were also detected in extracts from adult cardiac muscle. These data suggest that the MCK gene is controlled by different regulatory programs in adult cardiac and skeletal muscle.


2012 ◽  
Vol 35 (3) ◽  
pp. 455-462 ◽  
Author(s):  
Reema Khurana ◽  
Hitesh Kathuria ◽  
Arnab Mukhopadhyay ◽  
Sanjay Kapoor ◽  
Akhilesh K. Tyagi

2017 ◽  
Author(s):  
D. Leland Taylor ◽  
David A. Knowles ◽  
Laura J. Scott ◽  
Andrea H. Ramirez ◽  
Franceso Paolo Casale ◽  
...  

AbstractFrom whole organisms to individual cells, responses to environmental conditions are influenced by genetic makeup, where the effect of genetic variation on a trait depends on the environmental context. RNA-sequencing quantifies gene expression as a molecular trait, and is capable of capturing both genetic and environmental effects. In this study, we explore opportunities of using allele-specific expression (ASE) to discovercisacting genotype-environment interactions (GxE) - genetic effects on gene expression that depend on an environmental condition. Treating 17 common, clinical traits as approximations of the cellular environment of 267 skeletal muscle biopsies, we identify 10 candidate interaction quantitative trait loci (iQTLs) across 6 traits (12 unique gene-environment trait pairs; 10% FDR per trait) including sex, systolic blood pressure, and low-density lipoprotein cholesterol. Although using ASE is in principle a promising approach to detect GxE effects, replication of such signals can be challenging as validation requires harmonization of environmental traits across cohorts and a sufficient sampling of heterozygotes for a transcribed SNP. Comprehensive discovery and replication will require large human transcriptome datasets, or the integration of multiple transcribed SNPs, coupled with standardized clinical phenotyping.


Sign in / Sign up

Export Citation Format

Share Document