SEARCH · PubMed Health

Results for “regulatory element transcripts”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 595 records · Page 33Linked to original sources

PubMed1994

Nucleotide sequence and analysis of the mouse SPC3 promoter region.

Insulin is converted from the higher molecular weight proprotein, proinsulin by highly specific proteolytic cleavage at two dibasic amino acid sites. SPC3 and SPC2, two recently identified prohormone convertase that are specifically expressed in beta cells and other neuroendocrine cells, appear to be responsible for those cleavages. We have sequenced the 5'-upstream region of the SPC3 gene and examined its promotor/enhancer activity and most of several deletion mutants in several cell lines. This region contains no CAAT box but has several non-functional TATA-like sequences and several putative transcriptional regulatory elements, including AP-1, Sp1 and cAMP response elements. These features are not unlike those of the human SPC2 upstream region. In beta TC3 insulinoma cells, the sequence between the EcoRI (620 bp) and NsiI (702 bp) sites seems to be important for gene expression, while the sequence between the NsiI and DraI (775 bp) sites may contain strong enhancer element(s).

Amino Acid Sequence↗

PubMed1995

Functional characterization of the promoter region of the mouse protein kinase C gamma gene.

Promoter activity of protein kinase C (PKC) gamma gene was analysed by chloramphenicol acetyltransferase (CAT) assay using extracts from the cells transfected with various fusion constructs containing the 5'-flanking region of the mouse PKC gamma gene and CAT gene. Transient expression experiments in PC12 cells revealed that the upstream region of 87 bp from the transcriptional initiation site was sufficient for promoter activity. The region containing nucleotides 87 upstream from the transcriptional initiation site was shown to silence CAT activity in Balb/c3T3 cells, in which mRNA of PKC gamma was not detected, suggesting that this region might contain a transcriptional regulatory element for the cell type-specific expression of the PKC gamma gene.

Animals↗

PubMed1992

Gut-specific and developmental expression of a Caenorhabditis elegans cysteine protease gene.

A Caenorhabditis elegans cysteine protease gene fragment, amplified by PCR using conserved eukaryotic protease gene sequences as primers, was used as a probe to isolate cDNA and genomic clones. The genomic clone, which had a coding sequence of 987 bp interrupted by 2 small introns, was physically mapped to the middle of linkage group V. The predicted amino acid sequence of the mature C. elegans cysteine protease was homologous to those of other eukaryotic cysteine proteases, particularly to that of the nematode parasite Haemonchus contortus (50%) and to the cathepsin B-like hemoglobinase of the trematode parasite Schistosoma mansoni (54%). The pro region of the C. elegans protease was homologous only to that of the H. contortus enzyme, implying a similar mechanism of protease activation. The C. elegans cysteine protease gene was temporally regulated: abundant 1.1-kb transcripts were detected in larvae and adults, but not in embryos. Transcription also was spatially regulated, occurring only in the intestine. Like the vitellogenin genes, which also are transcribed exclusively in the intestine, the 5' end of the C. elegans cysteine protease gene had at least one copy of each of 2 heptameric sequences which may be transcriptional regulatory elements governing gut-specific expression.

Amino Acid Sequence↗

PubMed1992

Cloning and sequencing of an hsp70 gene of Schistosoma mansoni.

Schistosomes have a complex life cycle (vertebrate and molluscan hosts as well as larvae living freely in water) in which they are exposed to different environments and temperatures (20 degrees C - 37 degrees C). Since heat shock genes are activated in response to stress and during development [1], it is of interest to study the hsp70 gene family in schistosome. To approach this issue we have isolated from Schistosoma mansoni a genomic clone containing the complete coding region of hsp70 and the 5' flanking DNA with transcription regulatory elements including HSE (heat shock element) sequences.

Amino Acid Sequence↗

PubMed1994

Blasticidin S deaminase gene from Aspergillus terreus (BSD): a new drug resistance gene for transfection of mammalian cells.

Blasticidin S deaminase (BSD) is a drug inactivating enzyme produced by Aspergillus terreus, which convert blasticidin S (BS) to a non-toxic deamino-hydroxy derivative. The BSD gene was fused to SV 40 transcriptional regulatory elements and the resulting vector was used to transfect FM3A cells. Expression of BSD conferred resistance to BS and allowed efficient isolation of integrative transfectants which have stably maintained the BS-resistance phenotype after repeated transfer to fresh selective medium. The frequency of transfection was comparable to that with neo and about 80-times greater than with bsr, a BS-resistance gene of bacterial origin which can be used to isolate efficiently transfectant HeLa cells. Using BSD as a selectable marker, we obtained several stable cell lines expressing the firefly luciferase gene. Four independent transfectants among the randomly selected 5 BS-resistance colonies exhibited detectable luciferase activity under the control of dexamethasone-inducible promoter in the expression vector. The successful application of BSD strongly suggests the usefulness of BS as a versatile selective reagent for introduction of cloned DNA sequences into mammalian cells.

Aminohydrolases↗

PubMed1995

Characterization of the polyubiquitin gene in the marine red alga Gracilaria verrucosa.

We have cloned a nuclear gene (UBI6R) and corresponding cDNAs that encode polyubiquitin in the florideophycidean red alga Gracilaria verrucosa. The gene encodes a polyubiquitin composed of six tandem ubiquitin units, followed by a single glutamine residue. The deduced amino acid sequences are identical among all six units, and identical to the ubiquitin of the florideophyte Aglaothamnion neglectum. There is high sequence similarity among the red algal ubiquitins and those of animals, green plants, fungi and several protists. Only one polyubiquitin gene was found by Southern hybridization analysis of G. verrucosa nuclear DNA. The upstream region of the gene is rich in putative cis-acting transcription-regulatory elements, including a putative heat-responsive element. Poly(A) addition to UBI6R mRNA was observed in cDNAs at four different sites, implicating the sequences AATAAA and (or) AGTAAA as poly(A) addition signals. The polyubiquitin genes of red algae show features of concerted evolution, but appear to be subject to less sequence homogenization than those of animals.

Amino Acid Sequence↗

PubMed1992

Gene expression following transfection of fish cells.

Various genes containing different transcriptional regulatory elements (TRE) and the bacterial marker gene coding for chloramphenicol acetyl transferase were transfected into several fish cell lines to evaluate the efficiency of expression in comparison with mammalian cells. The CMV and RSV TRE were the most efficient non-inducible promoters in directing reporter gene expression. RSV and CMV appeared of similar potency in a stable fish cell line. The human HSP-70 promoter showed high potency in a carp and in a trout cell line after thermal induction. This promoter also induced the synthesis of human growth hormone directed by the corresponding cDNA, but not by the gene. RSV TRE was also able to drive the synthesis of bovine growth hormone when attached directly to the cDNA but not to the gene. These data suggest that non-fish gene TRE can be used to express foreign genes in fish cells or transgenic fish; however, in most cases they are relatively inefficient. The data also suggest that the translation and secretion machinery of fish cells can express efficiently foreign genes but that mammalian introns might be not processed properly in some cases.

Animals↗

PubMed1993

Identification of the functional regulatory region of the neurotrophin-3 gene promoter.

The 5'-flanking region of the human neurotrophin-3 (NT-3) gene was isolated from a human placental genomic library using the oligonucleotide corresponding to the 5'-noncoding region of the NT-3 cDNA as a probe. A 3.8 kbp genomic fragment containing the 5'-flanking region, the first exon and a portion of the first intron was isolated and sequenced. The transcriptional initiation site, identified by S1 nuclease mapping, was located 27 bp downstream from the TATA-like sequence. Several plasmids, in which the NT-3 promoter regions were fused to the chloramphenicol acetyltransferase (CAT) gene, were constructed. Transient expression in human glioma Hs683 cells demonstrated that a fragment of about 0.1 kbp from the transcriptional initiation site was sufficient for promoter activity. While, in human plasma cell leukemia ARH77 cells, in which NT-3 mRNA was not detected, the region upstream from -65 functioned to silence CAT activity. It is suggested that this region contains the transcriptional regulatory element for the specific expression of the NT-3 gene.

Base Sequence↗

PubMed1988

Nucleotide sequence of the Drosophila glucose-6-phosphate dehydrogenase gene and comparison with the homologous human gene.

Glucose-6-phosphate dehydrogenase (G6PD) has a major role in NADPH production and is found in almost all cell types. The structural gene for G6PD is X-linked in Drosophila melanogaster, as it is in most eukaryotic organisms, and due to its ubiquitous expression, it can be considered a typical 'housekeeping' gene. Here we present the complete nucleotide (nt) sequence of G6PD cDNAs as well as the genomic copy of the G6PD gene. The G6PD gene has three introns so that the protein-coding region is divided into four segments. The 5'-end of mature G6PD mRNA is located 289 +/- 1 nt upstream from the start codon. The sequence upstream from the transcription start point is G + T-rich and contains no commonly found transcription regulatory elements, such as a TATA box or GGGCGG sequence. D. melanogaster G6PD is 65% homologous with the human G6PD protein but has no homology with the human sequence for the first 42 amino acid residues. The G6PD gene was shown to be active when transduced to autosomal positions. For each transformant, G6PD activity in both male and female adults was not significantly different, indicating that the transduced gene, unlike the resident G6PD, is not dosage-compensated in males.

Amino Acid Sequence↗

PubMed1989

Isolation and structural analysis of the mouse beta-casein gene.

Three overlapping clones containing the entire beta-casein gene were isolated from a mouse genomic library constructed in bacteriophage lambda EMBL3. Within the three clones the 6.8-kb casein gene was flanked by about 6-kb (5') and about 10-kb (3') sequences. The complete nucleotide sequence of the gene and its immediate flanking regions was determined. The gene consisted of nine exons ranging from 21 bp to 525 bp separated by introns ranging from 81 bp to 1288 bp. The length of the first exon was 43 bp, as determined by primer extension. The comparison of this sequence with that of the rat beta-casein gene showed that the overall structure of the gene was highly conserved. However, the first intron of the mouse gene was 400 bp shorter than that of the rat gene. Further analysis of homology between this gene and four other casein genes from rat and bovine revealed the presence of four highly conserved sequences. A search for the consensus sequences of transcription-regulatory elements showed that several potential regulatory sequences were present in the gene and its 5' flanking region.

Animals↗

PubMed1991

A matched set of cat vectors for rapid mutational analysis of eukaryotic promoters and enhancers.

The eukaryotic cat expression vectors, pBRAMScat1 and pBRAMScat2, were constructed to simplify the analysis of genomic fragments containing putative transcriptional regulatory elements. These vectors contain the f1 filamentous phage origin of replication for single-stranded DNA rescue, and permit site-directed mutagenesis, and dideoxy sequencing of nested deletion mutants using commercial T3, T7 and M13 universal forward/reverse primers. The above features eliminate the need to shuttle back and forth between a conventional cloning vector and the cat expression vector during the analysis of putative eukaryotic gene regulatory elements. Plasmid pBRAMScat1 contains the bacterial chloramphenicol acetyltransferase-encoding gene (cat) and no eukaryotic promoter and was designed for the analysis of eukaryotic promoters. Plasmid pBRAMScat2 contains the cat gene under the control of the Herpes simplex virus thymidine kinase promoter and was designed for the analysis of eukaryotic enhancers.

Animals↗

PubMed1994

The role of a pentanucleotide repeat sequence, AGGGAAGGGA, in the regulation of JC virus DNA replication.

The human polyomavirus JCV differs from other papovaviruses in its narrow host range and tissue tropism for human glial cells. It is believed that the cell-specific tropism of JCV to glial cells rests, at least in part, in transcription of the viral early gene that encodes the large tumor antigen (T-antigen). The secondary stage, however, which restricts the replication cycle of JCV to primate cells, is controlled at the level of viral DNA replication. In this study, we demonstrate that a cis-acting transcription regulatory element encompassing the pentanucleotide repeat sequence AGGGAAGGGA (penta), which is located in close proximity to the origin of DNA replication, plays an important role in the replication of viral DNA mediated by the JCV T-antigen, but not T-antigen derived from SV40. Analysis of DNA structure by diethyl pyrocarbonate (DEPC) has revealed that mutations within the penta which affect DNA replication also alter the structure of the neighboring A+T-rich region. These results suggest that, in addition to the regulatory role in viral gene expression, the penta may function as a DNA structural element which is important for JCV DNA replication mediated by the JCV T-antigen.

Animals↗

PubMed2004

Development of transgenic chickens expressing enhanced green fluorescent protein.

In this work we demonstrated the successful production of transgenic chickens expressing the enhanced green fluorescence protein (EGFP) gene. Replication-defective recombinant retroviruses produced from vesicular stomatitis virus G glycoprotein pseudotyped retrovirus vector system were injected beneath the blastoderm of non-incubated chicken embryos (stage X). From 129 injected eggs, 13 chicks hatched after 21 days of incubation. All hatched chicks were found to express vector-encoded EGFP gene, which was under the control of the Rous sarcoma virus promoter and boosted post-transcriptionally by woodchuck hepatitis virus post-transcriptional regulatory element sequence. Green fluorescent signals, indicative of the EGFP gene expression, were detected in various body parts, including head, limb, eye, toe, and several internal organs. Genomic incorporation of the transgene was also proven by Southern blot assay. Our results show the exceptional versatile effectiveness of the EGFP gene as a marker in the gene expression-related studies which therefore would be very helpful in establishing a useful transgenic chicken model system for studies on embryo development and for efficient production of transgenic chickens as bioreactors.

Animals↗

PubMed2004

Transglutaminase activity and transglutaminase mRNA transcripts in gerbil brain ischemia.

Brain injury of the ischemia/reperfusion type induces neuronal damage, mainly by excitatory amino acid release, intracellular Ca(2+) overload and reactive oxygen species production. We have previously demonstrated that glutamate exposure increased transglutaminase activity and transglutaminase 2 expression in cultured cerebellar granule cells and astrocytes. The aim of this study is to evaluate changes in transglutaminase activity and expression using a gerbil model of global cerebral ischemia. Moreover, the distribution and amounts of different transglutaminase isoforms were examined. Transglutaminase activity was measured by incorporation of [(3)H]putrescine into dimethylcasein throughout 48 h of reperfusion following a 3 min occlusion. Compared to sham-operated brains, significant increases were found in the ischemic hippocampus at 24 h of reperfusion, while minor changes were observed in the cortex. RT-PCR demonstrated the presence of significant mRNA amounts of transglutaminase 2 and transglutaminase 1, both in the hippocampus and the cerebral cortex, while low levels were found for transglutaminase 3 transcripts. Interestingly, transglutaminase 2 and transglutaminase 1 mRNAs were 4-fold and 2-fold increased, respectively, in the ischemic hippocampus after 24 h of reperfusion. Western blot analysis of transglutaminase 2 expression confirmed a strong up-regulation in the ischemic hippocampus. However, it is possible to hypothesize that different expression rates of transglutaminase isoforms may be dependent on different responsiveness of their transcription regulatory elements to intracellular calcium overload following excitotoxic cell injury. Our results suggest that increases in transglutaminases may be part of the tissue stress response in global brain ischemia.

Animals↗

PubMed2005

Enhancer sequence conservation between vertebrates is favoured in developmental regulator genes.

Sequence conservation has been used to find genes and to pinpoint functional non-coding sequences such as transcriptional regulatory elements. In this article, we analysed the conservation of 104 experimentally validated murine enhancer sequences between the mouse and zebrafish genomes. Surprisingly, only 10.5% of the mouse enhancers have homologues in zebrafish. All of the genes with conserved cis-elements have regulatory functions during embryonic development, perhaps reflecting substantial structural constraints on the integration of spatio-temporal signalling cues during the formation of the vertebrate body.

Animals↗

PubMed2006

Different words, same meaning: understanding the languages of the genome.

There is undeniable value in using sequence comparison to identify putative regulatory sequences. However, a recent report has demonstrated that not all regulatory sequences are evolutionarily conserved. Cis-acting sequences around the RET gene, conserved in mammals but not in fish, are able to reproduce patterns of RET expression in zebrafish embryos. It is as yet unclear whether these sequences are 'below the radar' of current sequence alignment tools or whether their functional homology is not sequence based.

Animals↗

PubMed2002

Expression and promoter analysis of SLC19A2 in the human intestine.

The molecular mechanism and regulation of the intestinal uptake process of dietary thiamine is not well understood. Previous studies have established the involvement of a carrier-mediated system for thiamine uptake in the human intestine. Recently a human thiamine transporter, SLC19A2, was cloned from a number of human tissues. Little, however, is known about expression of the SLC19A2 message along the native human gastrointestinal tract, and no analysis of its promoter in intestinal tissue is available. Therefore, the current studies were aimed at investigating the expression of SLC19A2 in the human gastrointestinal tract and at analyzing the promoter of this potential intestinal thiamine transporter. First we cloned SLC19A2 cDNA from a human intestinal cell line (Caco-2) by reverse transcriptase-polymerase chain reaction, then used this cDNA as a probe in Northern blot analysis. SLC19A2 message was found to be expressed in all gastrointestinal tissues in the following order: liver>stomach>duodenum>jejunum>colon>cecum>rectum>ileum. SLC19A2 was also expressed at the protein level in Caco-2 cells and in native human small intestine by Western blot analysis. We also cloned the 5'-regulatory region of the SLC19A2 gene and confirmed activity of its promoter following transfection into intestinal epithelial Caco-2 cells. Furthermore, we identified the minimal promoter region required for basal activity of SLC19A2 in these cells which was found to be mainly encoded in a sequence between -356 and -36, and included multiple cis-regulatory elements. Transcription initiation sites of the SLC19A2 gene in intestinal epithelial Caco-2 cells were also identified by 5'-rapid amplification of cDNA ends. These results demonstrate that SLC19A2 is expressed in various regions of the human gastrointestinal tract. In addition, the results provide the first characterization of the SLC19A2 promoter. These findings raise the possibility that SLC19A2 may play a role in the normal intestinal thiamine absorption process.

Base Sequence↗

PubMed2004

Transient expression analysis of the mouse ornithine decarboxylase antizyme haploid-specific promoter using in vivo electroporation.

The testicular isoform of the ornithine decarboxylase antizyme (OAZt) gene is expressed exclusively in the haploid spermatids of mice. The 357-bp region, which includes a TATA-less promoter and an untranslated region, is sufficient for OAZt gene expression in the spermatids of transgenic mice. In this study, in vivo transient transfection to living mouse testes was used to define the transcriptional regulatory elements of the OAZt gene promoter. We found that the 10-bp element that contains an initiator (Inr) plays a central role as the core promoter, in combination with a downstream element, while two cyclic adenosine monophosphate-responsive element (CRE)-like sites in the upstream region also contribute to promoter activity. The electrophoretic mobility shift assay showed binding of the testis-specific factors to these elements. Our results show that the in vivo DNA transfer technique enables detailed analysis of haploid germ cell-specific gene regulation in mice.

Animals↗