Reconstructing Dynamic Promoter Activity Profiles from Reporter Gene Data.

Science.gov (United States)

Kannan, Soumya; Sams, Thomas; Maury, Jérôme; Workman, Christopher T

2018-03-16

Accurate characterization of promoter activity is important when designing expression systems for systems biology and metabolic engineering applications. Promoters that respond to changes in the environment enable the dynamic control of gene expression without the necessity of inducer compounds, for example. However, the dynamic nature of these processes poses challenges for estimating promoter activity. Most experimental approaches utilize reporter gene expression to estimate promoter activity. Typically the reporter gene encodes a fluorescent protein that is used to infer a constant promoter activity despite the fact that the observed output may be dynamic and is a number of steps away from the transcription process. In fact, some promoters that are often thought of as constitutive can show changes in activity when growth conditions change. For these reasons, we have developed a system of ordinary differential equations for estimating dynamic promoter activity for promoters that change their activity in response to the environment that is robust to noise and changes in growth rate. Our approach, inference of dynamic promoter activity (PromAct), improves on existing methods by more accurately inferring known promoter activity profiles. This method is also capable of estimating the correct scale of promoter activity and can be applied to quantitative data sets to estimate quantitative rates.

Gene activation regresses atherosclerosis, promotes health, and enhances longevity

Directory of Open Access Journals (Sweden)

Luoma Pauli V

2010-07-01

Full Text Available Abstract Background Lifestyle factors and pharmacological compounds activate genetic mechanisms that influence the development of atherosclerotic and other diseases. This article reviews studies on natural and pharmacological gene activation that promotes health and enhances longevity. Results Living habits including healthy diet and regular physical activity, and pharmacotherapy, upregulate genes encoding enzymes and apolipoprotein and ATP-binding cassette transporters, acting in metabolic processes that promote health and increase survival. Cytochrome P450-enzymes, physiological factors in maintaining cholesterol homeostasis, generate oxysterols for the elimination of surplus cholesterol. Hepatic CTP:phosphocholine cytidylyltransferase-α is an important regulator of plasma HDL-C level. Gene-activators produce plasma lipoprotein profile, high HDL-C, HDL2-C and HDL-C/cholesterol ratio, which is typical of low risk of atherosclerotic disease, and also of exceptional longevity together with reduced prevalence of cardiovascular, metabolic and other diseases. High HDL contributes to protection against inflammation, oxidation and thrombosis, and associates with good cognitive function in very old people. Avoiding unhealthy stress and managing it properly promotes health and increases life expectancy. Conclusions Healthy living habits and gene-activating xenobiotics upregulate mechanisms that produce lipoprotein pattern typical of very old people and enhance longevity. Lipoprotein metabolism and large HDL2 associate with the process of living a very long life. Major future goals for health promotion are the improving of commitment to both wise lifestyle choices and drug therapy, and further the developing of new and more effective and well tolerated drugs and treatments.

Development of chimeric gene promoters responsive to hypoxia and ionizing radiation

International Nuclear Information System (INIS)

Zheng Aiqing; Yu Jinming

2004-01-01

The authors describe two systems that make use of gene-directed enzyme prodrug therapy, regulated by radiation or hypoxic-responsive promoters. The use of treatment-, condition- or tumor-specific promoters to control gene-directed enzyme prodrug therapy is one such method for targeting gene expression to the tumor. The development of such strategies that achieve tumor targeted expression of genes via selective promoters will enable improved specificity and targeting thereby addressing one of the major limitations of cancer gene therapy

Insulators form gene loops by interacting with promoters in Drosophila.

Science.gov (United States)

Erokhin, Maksim; Davydova, Anna; Kyrchanova, Olga; Parshikov, Alexander; Georgiev, Pavel; Chetverina, Darya

2011-09-01

Chromatin insulators are regulatory elements involved in the modulation of enhancer-promoter communication. The 1A2 and Wari insulators are located immediately downstream of the Drosophila yellow and white genes, respectively. Using an assay based on the yeast GAL4 activator, we have found that both insulators are able to interact with their target promoters in transgenic lines, forming gene loops. The existence of an insulator-promoter loop is confirmed by the fact that insulator proteins could be detected on the promoter only in the presence of an insulator in the transgene. The upstream promoter regions, which are required for long-distance stimulation by enhancers, are not essential for promoter-insulator interactions. Both insulators support basal activity of the yellow and white promoters in eyes. Thus, the ability of insulators to interact with promoters might play an important role in the regulation of basal gene transcription.

Mechanosensitive promoter region in the human HB-GAM gene

DEFF Research Database (Denmark)

Liedert, Astrid; Kassem, Moustapha; Claes, Lutz

2009-01-01

Mechanical loading is essential for maintaining bone mass in the adult skeleton. However, the underlying process of the transfer of the physical stimulus into a biochemical response, which is termed mechanotransduction is poorly understood. Mechanotransduction results in the modulation of gene...... cells. Analysis of the human HB-GAM gene upstream regulatory region with luciferase reporter gene assays revealed that the upregulation of HB-GAM expression occurred at the transcriptional level and was mainly dependent on the HB-GAM promoter region most upstream containing three potential AP-1 binding...

Isolating Barley ( Hordeum vulgare L.) B1 Hordein Gene Promoter ...

African Journals Online (AJOL)

Promoters play the most important role in determining the temporal and spatial expression pattern and transcript level of a gene. Some strong constitutive promoters, such as cauliflower mosaic virus 35s promoter, are widely used in plant genetic engineering research. However, the expression levels of the foreign genes in ...

The role of germline promoters and I exons in cytokine-induced gene-specific class switch recombination.

Science.gov (United States)

Dunnick, Wesley A; Shi, Jian; Holden, Victoria; Fontaine, Clinton; Collins, John T

2011-01-01

Germline transcription precedes class switch recombination (CSR). The promoter regions and I exons of these germline transcripts include binding sites for activation- and cytokine-induced transcription factors, and the promoter regions/I exons are essential for CSR. Therefore, it is a strong hypothesis that the promoter/I exons regions are responsible for much of cytokine-regulated, gene-specific CSR. We tested this hypothesis by swapping the germline promoter and I exons for the murine γ1 and γ2a H chain genes in a transgene of the entire H chain C-region locus. We found that the promoter/I exon for γ1 germline transcripts can direct robust IL-4-induced recombination to the γ2a gene. In contrast, the promoter/I exon for the γ2a germline transcripts works poorly in the context of the γ1 H chain gene, resulting in expression of γ1 H chains that is level. Nevertheless, the small amount of recombination to the chimeric γ1 gene is induced by IFN-γ. These results suggest that cytokine regulation of CSR, but not the magnitude of CSR, is regulated by the promoter/I exons.

Novel strong tissue specific promoter for gene expression in human germ cells

Directory of Open Access Journals (Sweden)

Kuzmin Denis

2010-08-01

Full Text Available Abstract Background Tissue specific promoters may be utilized for a variety of applications, including programmed gene expression in cell types, tissues and organs of interest, for developing different cell culture models or for use in gene therapy. We report a novel, tissue-specific promoter that was identified and engineered from the native upstream regulatory region of the human gene NDUFV1 containing an endogenous retroviral sequence. Results Among seven established human cell lines and five primary cultures, this modified NDUFV1 upstream sequence (mNUS was active only in human undifferentiated germ-derived cells (lines Tera-1 and EP2102, where it demonstrated high promoter activity (~twice greater than that of the SV40 early promoter, and comparable to the routinely used cytomegaloviral promoter. To investigate the potential applicability of the mNUS promoter for biotechnological needs, a construct carrying a recombinant cytosine deaminase (RCD suicide gene under the control of mNUS was tested in cell lines of different tissue origin. High cytotoxic effect of RCD with a cell-death rate ~60% was observed only in germ-derived cells (Tera-1, whereas no effect was seen in a somatic, kidney-derived control cell line (HEK293. In further experiments, we tested mNUS-driven expression of a hyperactive Sleeping Beauty transposase (SB100X. The mNUS-SB100X construct mediated stable transgene insertions exclusively in germ-derived cells, thereby providing further evidence of tissue-specificity of the mNUS promoter. Conclusions We conclude that mNUS may be used as an efficient promoter for tissue-specific gene expression in human germ-derived cells in many applications. Our data also suggest that the 91 bp-long sequence located exactly upstream NDUFV1 transcriptional start site plays a crucial role in the activity of this gene promoter in vitro in the majority of tested cell types (10/12, and an important role - in the rest two cell lines.

Characterization of promoter sequence of toll-like receptor genes in Vechur cattle

Directory of Open Access Journals (Sweden)

R. Lakshmi

2016-06-01

Full Text Available Aim: To analyze the promoter sequence of toll-like receptor (TLR genes in Vechur cattle, an indigenous breed of Kerala with the sequence of Bos taurus and access the differences that could be attributed to innate immune responses against bovine mastitis. Materials and Methods: Blood samples were collected from Jugular vein of Vechur cattle, maintained at Vechur cattle conservation center of Kerala Veterinary and Animal Sciences University, using an acid-citrate-dextrose anticoagulant. The genomic DNA was extracted, and polymerase chain reaction was carried out to amplify the promoter region of TLRs. The amplified product of TLR2, 4, and 9 promoter regions was sequenced by Sanger enzymatic DNA sequencing technique. Results: The sequence of promoter region of TLR2 of Vechur cattle with the B. taurus sequence present in GenBank showed 98% similarity and revealed variants for four sequence motifs. The sequence of the promoter region of TLR4 of Vechur cattle revealed 99% similarity with that of B. taurus sequence but not reveals significant variant in motifregions. However, two heterozygous loci were observed from the chromatogram. Promoter sequence of TLR9 gene also showed 99% similarity to B. taurus sequence and revealed variants for four sequence motifs. Conclusion: The results of this study indicate that significant variation in the promoter of TLR2 and 9 genes in Vechur cattle breed and may potentially link the influence the innate immunity response against mastitis diseases.

HOX Gene Promoter Prediction and Inter-genomic Comparison: An Evo-Devo Study

Directory of Open Access Journals (Sweden)

Marla A. Endriga

2010-10-01

Full Text Available Homeobox genes direct the anterior-posterior axis of the body plan in eukaryotic organisms. Promoter regions upstream of the Hox genes jumpstart the transcription process. CpG islands found within the promoter regions can cause silencing of these promoters. The locations of the promoter regions and the CpG islands of Homeo sapiens sapiens (human, Pan troglodytes (chimpanzee, Mus musculus (mouse, and Rattus norvegicus (brown rat are compared and related to the possible influence on the specification of the mammalian body plan. The sequence of each gene in Hox clusters A-D of the mammals considered were retrieved from Ensembl and locations of promoter regions and CpG islands predicted using Exon Finder. The predicted promoter sequences were confirmed via BLAST and verified against the Eukaryotic Promoter Database. The significance of the locations was determined using the Kruskal-Wallis test. Among the four clusters, only promoter locations in cluster B showed significant difference. HOX B genes have been linked with the control of genes that direct the development of axial morphology, particularly of the vertebral column bones. The magnitude of variation among the body plans of closely-related species can thus be partially attributed to the promoter kind, location and number, and gene inactivation via CpG methylation.

Characteristic differences between the promoters of intron-containing and intronless ribosomal protein genes in yeast

Directory of Open Access Journals (Sweden)

Vingron Martin

2008-10-01

Full Text Available Abstract Background More than two thirds of the highly expressed ribosomal protein (RP genes in Saccharomyces cerevisiae contain introns, which is in sharp contrast to the genome-wide five percent intron-containing genes. It is well established that introns carry regulatory sequences and that the transcription of RP genes is extensively and coordinately regulated. Here we test the hypotheses that introns are innately associated with heavily transcribed genes and that introns of RP genes contribute regulatory TF binding sequences. Moreover, we investigate whether promoter features are significantly different between intron-containing and intronless RP genes. Results We find that directly measured transcription rates tend to be lower for intron-containing compared to intronless RP genes. We do not observe any specifically enriched sequence motifs in the introns of RP genes other than those of the branch point and the two splice sites. Comparing the promoters of intron-containing and intronless RP genes, we detect differences in number and position of Rap1-binding and IFHL motifs. Moreover, the analysis of the length distribution and the folding free energies suggest that, at least in a sub-population of RP genes, the 5' untranslated sequences are optimized for regulatory function. Conclusion Our results argue against the direct involvement of introns in the regulation of transcription of highly expressed genes. Moreover, systematic differences in motif distributions suggest that RP transcription factors may act differently on intron-containing and intronless gene promoters. Thus, our findings contribute to the decoding of the RP promoter architecture and may fuel the discussion on the evolution of introns.

Senataxin Mutation Reveals How R-Loops Promote Transcription by Blocking DNA Methylation at Gene Promoters.

Science.gov (United States)

Grunseich, Christopher; Wang, Isabel X; Watts, Jason A; Burdick, Joshua T; Guber, Robert D; Zhu, Zhengwei; Bruzel, Alan; Lanman, Tyler; Chen, Kelian; Schindler, Alice B; Edwards, Nancy; Ray-Chaudhury, Abhik; Yao, Jianhua; Lehky, Tanya; Piszczek, Grzegorz; Crain, Barbara; Fischbeck, Kenneth H; Cheung, Vivian G

2018-02-01

R-loops are three-stranded nucleic acid structures found abundantly and yet often viewed as by-products of transcription. Studying cells from patients with a motor neuron disease (amyotrophic lateral sclerosis 4 [ALS4]) caused by a mutation in senataxin, we uncovered how R-loops promote transcription. In ALS4 patients, the senataxin mutation depletes R-loops with a consequent effect on gene expression. With fewer R-loops in ALS4 cells, the expression of BAMBI, a negative regulator of transforming growth factor β (TGF-β), is reduced; that then leads to the activation of the TGF-β pathway. We uncovered that genome-wide R-loops influence promoter methylation of over 1,200 human genes. DNA methyl-transferase 1 favors binding to double-stranded DNA over R-loops. Thus, in forming R-loops, nascent RNA blocks DNA methylation and promotes further transcription. Hence, our results show that nucleic acid structures, in addition to sequences, influence the binding and activity of regulatory proteins. Copyright © 2017 Elsevier Inc. All rights reserved.

Tumor Restrictive Suicide Gene Therapy for Glioma Controlled by the FOS Promoter.

Directory of Open Access Journals (Sweden)

Jianqing Pan

Full Text Available Effective suicide gene delivery and expression are crucial to achieving successful effects in gene therapy. An ideal tumor-specific promoter expresses therapeutic genes in tumor cells with minimal normal tissue expression. We compared the activity of the FOS (FBJ murine osteosarcoma viral oncogene homolog promoter with five alternative tumor-specific promoters in glioma cells and non-malignant astrocytes. The FOS promoter caused significantly higher transcriptional activity in glioma cell lines than all alternative promoters with the exception of CMV. The FOS promoter showed 13.9%, 32.4%, and 70.8% of the transcriptional activity of CMV in three glioma cell lines (U87, U251, and U373. Importantly, however, the FOS promoter showed only 1.6% of the transcriptional activity of CMV in normal astrocytes. We also tested the biologic activity of recombinant adenovirus containing the suicide gene herpes simplex virus thymidine kinase (HSV-tk driven by the FOS promoter, including selective killing efficacy in vitro and tumor inhibition rate in vivo. Adenoviral-mediated delivery of the HSV-tk gene controlled by the FOS promoter conferred a cytotoxic effect on human glioma cells in vitro and in vivo. This study suggests that use of the FOS-tk adenovirus system is a promising strategy for glioma-specific gene therapy but still much left for improvement.

Characterization of carotenoid hydroxylase gene promoter in Haematococcus pluvialis.

Science.gov (United States)

Meng, C X; Wei, W; Su, Z- L; Qin, S

2006-10-01

Astaxanthin, a high-value ketocarotenoid is mainly used in fish aquaculture. It also has potential in human health due to its higher antioxidant capacity than beta-carotene and vitamin E. The unicellular green alga Haematococcus pluvialis is known to accumulate astaxanthin in response to environmental stresses, such as high light intensity and salt stress. Carotenoid hydroxylase plays a key role in astaxanthin biosynthesis in H. pluvialis. In this paper, we report the characterization of a promoter-like region (-378 to -22 bp) of carotenoid hydroxylase gene by cloning, sequence analysis and functional verification of its 919 bp 5'-flanking region in H. pluvialis. The 5'-flanking region was characterized using micro-particle bombardment method and transient expression of LacZ reporter gene. Results of sequence analysis showed that the 5'-flanking region might have putative cis-acting elements, such as ABA (abscisic acid)-responsive element (ABRE), C-repeat/dehydration responsive element (C-repeat/DRE), ethylene-responsive element (ERE), heat-shock element (HSE), wound-responsive element (WUN-motif), gibberellin-responsive element (P-box), MYB-binding site (MBS) etc., except for typical TATA and CCAAT boxes. Results of 5' deletions construct and beta-galactosidase assays revealed that a highest promoter-like region might exist from -378 to -22 bp and some negative regulatory elements might lie in the region from -919 to -378 bp. Results of site-directed mutagenesis of a putative C-repeat/DRE and an ABRE-like motif in the promoter-like region (-378 to -22 bp) indicated that the putative C-repeat/DRE and ABRE-like motif might be important for expression of carotenoid hydroxylase gene.

Promoter-wide hypermethylation of the ribosomal RNA gene promoter in the suicide brain.

Directory of Open Access Journals (Sweden)

Patrick O McGowan

Full Text Available BACKGROUND: Alterations in gene expression in the suicide brain have been reported and for several genes DNA methylation as an epigenetic regulator is thought to play a role. rRNA genes, that encode ribosomal RNA, are the backbone of the protein synthesis machinery and levels of rRNA gene promoter methylation determine rRNA transcription. METHODOLOGY/PRINCIPAL FINDINGS: We test here by sodium bisulfite mapping of the rRNA promoter and quantitative real-time PCR of rRNA expression the hypothesis that epigenetic differences in critical loci in the brain are involved in the pathophysiology of suicide. Suicide subjects in this study were selected for a history of early childhood neglect/abuse, which is associated with decreased hippocampal volume and cognitive impairments. rRNA was significantly hypermethylated throughout the promoter and 5' regulatory region in the brain of suicide subjects, consistent with reduced rRNA expression in the hippocampus. This difference in rRNA methylation was not evident in the cerebellum and occurred in the absence of genome-wide changes in methylation, as assessed by nearest neighbor. CONCLUSIONS/SIGNIFICANCE: This is the first study to show aberrant regulation of the protein synthesis machinery in the suicide brain. The data implicate the epigenetic modulation of rRNA in the pathophysiology of suicide.

Characterization and functional analysis of the Paralichthys olivaceus prdm1 gene promoter.

Science.gov (United States)

Li, Peizhen; Wang, Bo; Cao, Dandan; Liu, Yuezhong; Zhang, Quanqi; Wang, Xubo

2017-10-01

PR domain containing protein 1 (Prdm1) is a transcriptional repressor identified in various species and plays multiple important roles in immune response and embryonic development. However, little is known about the transcriptional regulation of the prdm1 gene. This study aims to characterize the promoter of Paralichthys olivaceus prdm1 (Po-prdm1) gene and determine the regulatory mechanism of Po-prdm1 expression. A 2000bp-long 5'-flanking region (translation initiation site designated as +1) of the Po-prdm1 gene was isolated and characterized. The regulatory elements in this fragment were then investigated and many putative transcription factor (TF) binding sites involved in immunity and multiple tissue development were identified. A 5'-deletion analysis was then conducted, and the ability of the deletion mutants to promote luciferase and green fluorescent protein (GFP) expression in a flounder gill cell line was examined. The results revealed that the minimal promoter is located in the region between -446 and -13bp, and the region between -1415 and -13bp enhanced the promoter activity. Site-directed mutation analysis was subsequently performed on the putative regulatory elements sites, and the results indicated that FOXP1, MSX and BCL6 binding sites play negative functional roles in the regulation of the Po-prdm1 expression in FG cells. In vivo analysis demonstrated that a GFP reporter gene containing 1.4kb-long promoter fragment (-1415/-13) was expressed in the head and trunk muscle fibres of transient transgenic zebrafish embryos. Our study provided the basic information for the exploration of Po-prdm1 regulation and expression. Copyright © 2017 Elsevier Inc. All rights reserved.

The Relationship between FHIT Gene Promoter Methylation and Lung Cancer Risk: 
a Meta-analysis

Directory of Open Access Journals (Sweden)

Yichang SUN

2014-03-01

Full Text Available Background and objective Tumor-suppressor gene promoter DNA methylation in tumor cells is associated with its reduced expression. FHIT (fragile histindine triad was one of the important tumor suppressor genes which was found hypermethylated in the promoter region in most of tumors. The aim of this study is to evaluate the relationship between FIHT gene promother methylation and lung cancer risk by meta-analysis. Methods By searching Pubmed, CNKI and Wanfang, the open published articles related to FHIT gene promoter methylation and lung carcinoma risk were collected. The odds ratio (OR and range of FHIT gene of cancer tissue of lung cancer patients compared with normal lung tissue, plasma and the bronchial lavage fluid were pooled by statistical software Stata 11.0. Results Eleven studies were finally included in this meta-analysis. The median methylation rate were Pmedian=40.0% (0-68.3%, Pmedian=8.7% (0-35.0%, Pmedian=33.3% (17.1%-38.3% and Pmedian=35.9% (31.1%-50.8% in cancer tissue, NLT, BALF and plasm respectively. The pooled results showed the methylation rate in tumor tissue was much higer than that of NLT OR=5.82 (95%CI: 3.74-9.06, P0.05 and plasma OR=1.41 (95%CI: 0.90-2.20, P>0.05. Conclusion Hypermethylation of FHIT gene promoter region was found more frequent in cancer tissue than that of NLT which may demonstrated association between lung cancer risk and FHIT gene promoter methylation.

Promoter Hypermethylation of the ATM Gene as a Novel Biomarker for Breast Cancer

Science.gov (United States)

Begam, Nasrin; Jamil, Kaiser; Raju, Suryanarayana G

2017-11-26

Background: Breast cancer may be induced by activation of protooncogenes to oncogenes and in many cases inactivation of tumor suppressor genes. Ataxia telangiectasia mutated (ATM) is an important tumor suppressor gene which plays central roles in the maintenance of genomic integrity by activating cell cycle checkpoints and promoting repair of double-strand breaks of DNA. In breast cancer, decrease ATM expression correlates with a poor outcome; however, the molecular mechanisms underlying downregulation are still unclear. Promoter hypermethylation may contribute in downregulation. Hence the present investigation was designed to evaluate promoter methylation and expression of the ATM gene in breast cancer cases, and to determine links with clinical and demographic manifestations, in a South Indian population. Methods: Tumor biopsy samples were collected from 50 pathologically confirmed sporadic breast cancer cases. DNA was isolated from tumor and adjacent non-tumorous regions, and sodium bisulfite conversion and methylation-specific PCR were performed using MS-PCR primers for the ATM promoter region. In addition, ATM mRNA expression was also analyzed for all samples using real-time PCR. Results: Fifty eight percent (58%) of cancer tissue samples showed promoter hypermethylation for the ATM gene, in contrast to only 4.44% of normal tissues (p= 0.0001). Furthermore, ATM promoter methylation was positively associated with age (p = 0.01), tumor size (p=0.045) and advanced stage of disease i.e. stages III and IV (p =0.019). An association between promoter hypermethylation and lower expression of ATM mRNA was also found (p=0.035). Conclusion: We report for the first time that promoter hypermethylation of ATM gene may be useful as a potential new biomarker for breast cancer, especially in the relatively young patients. Creative Commons Attribution License

Regulated expression of the human cytomegalovirus pp65 gene: Octamer sequence in the promoter is required for activation by viral gene products

International Nuclear Information System (INIS)

Depto, A.S.; Stenberg, R.M.

1989-01-01

To better understand the regulation of late gene expression in human cytomegalovirus (CMV)-infected cells, the authors examined expression of the gene that codes for the 65-kilodalton lower-matrix phosphoprotein (pp65). Analysis of RNA isolated at 72 h from cells infected with CMV Towne or ts66, a DNA-negative temperature-sensitive mutant, supported the fact that pp65 is expressed at low levels prior to viral DNA replication but maximally expressed after the initiation of viral DNA replication. To investigate promoter activation in a transient expression assay, the pp65 promoter was cloned into the indicator plasmid containing the gene for chloramphenicol acetyltransferase (CAT). Transfection of the promoter-CAT construct and subsequent superinfection with CMV resulted in activation of the promoter at early times after infection. Cotransfection with plasmids capable of expressing immediate-early (IE) proteins demonstrated that the promoter was activated by IE proteins and that both IE regions 1 and 2 were necessary. These studies suggest that interactions between IE proteins and this octamer sequence may be important for the regulation and expression of this CMV gene

The Mouse Solitary Odorant Receptor Gene Promoters as Models for the Study of Odorant Receptor Gene Choice.

Directory of Open Access Journals (Sweden)

Andrea Degl'Innocenti

Full Text Available In vertebrates, several anatomical regions located within the nasal cavity mediate olfaction. Among these, the main olfactory epithelium detects most conventional odorants. Olfactory sensory neurons, provided with cilia exposed to the air, detect volatile chemicals via an extremely large family of seven-transmembrane chemoreceptors named odorant receptors. Their genes are expressed in a monogenic and monoallelic fashion: a single allele of a single odorant receptor gene is transcribed in a given mature neuron, through a still uncharacterized molecular mechanism known as odorant receptor gene choice.Odorant receptor genes are typically arranged in genomic clusters, but a few are isolated (we call them solitary from the others within a region broader than 1 Mb upstream and downstream with respect to their transcript's coordinates. The study of clustered genes is problematic, because of redundancy and ambiguities in their regulatory elements: we propose to use the solitary genes as simplified models to understand odorant receptor gene choice.Here we define number and identity of the solitary genes in the mouse genome (C57BL/6J, and assess the conservation of the solitary status in some mammalian orthologs. Furthermore, we locate their putative promoters, predict their homeodomain binding sites (commonly present in the promoters of odorant receptor genes and compare candidate promoter sequences with those of wild-caught mice. We also provide expression data from histological sections.In the mouse genome there are eight intact solitary genes: Olfr19 (M12, Olfr49, Olfr266, Olfr267, Olfr370, Olfr371, Olfr466, Olfr1402; five are conserved as solitary in rat. These genes are all expressed in the main olfactory epithelium of three-day-old mice. The C57BL/6J candidate promoter of Olfr370 has considerably varied compared to its wild-type counterpart. Within the putative promoter for Olfr266 a homeodomain binding site is predicted. As a whole, our findings

Cancer cell specific cytotoxic gene expression mediated by ARF tumor suppressor promoter constructs

International Nuclear Information System (INIS)

Kurayoshi, Kenta; Ozono, Eiko; Iwanaga, Ritsuko; Bradford, Andrew P.; Komori, Hideyuki; Ohtani, Kiyoshi

2014-01-01

is activated by E2F only in cancer cells and therefore may be more cancer cell-specific than E2F1 promoter to drive gene expression. We show here that the ARF promoter has lower activity in normal growing fibroblasts and shows higher cancer cell-specificity compared to the E2F1 promoter. We also demonstrate that adenovirus expressing HSV-TK under the control of the ARF promoter shows lower cytotoxicity than that of the E2F1 promoter, in normal growing fibroblasts but has equivalent cytotoxicity in cancer cell lines. These results suggest that the ARF promoter, which is specifically activated by deregulated E2F activity, is an excellent candidate to drive therapeutic cytotoxic gene expression, specifically in cancer cells

Cancer cell specific cytotoxic gene expression mediated by ARF tumor suppressor promoter constructs

Energy Technology Data Exchange (ETDEWEB)

Kurayoshi, Kenta [Department of Bioscience, School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337 (Japan); Ozono, Eiko [Centre for Molecular Oncology, Barts Cancer Institute, Queen Mary, University of London, John Vane Science Centre, Charterhouse Square, London EC1M 6BQ (United Kingdom); Iwanaga, Ritsuko; Bradford, Andrew P. [Department of Obstetrics and Gynecology, University of Colorado School of Medicine, Anschutz Medical Campus, 12800 East 19th Avenue, Aurora, CO 80045 (United States); Komori, Hideyuki [Center for Stem Cell Biology, Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109 (United States); Ohtani, Kiyoshi, E-mail: btm88939@kwansei.ac.jp [Department of Bioscience, School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337 (Japan)

2014-07-18

is activated by E2F only in cancer cells and therefore may be more cancer cell-specific than E2F1 promoter to drive gene expression. We show here that the ARF promoter has lower activity in normal growing fibroblasts and shows higher cancer cell-specificity compared to the E2F1 promoter. We also demonstrate that adenovirus expressing HSV-TK under the control of the ARF promoter shows lower cytotoxicity than that of the E2F1 promoter, in normal growing fibroblasts but has equivalent cytotoxicity in cancer cell lines. These results suggest that the ARF promoter, which is specifically activated by deregulated E2F activity, is an excellent candidate to drive therapeutic cytotoxic gene expression, specifically in cancer cells.

Promoter polymorphisms in genes involved in porcine myogenesis influence their transcriptional activity.

Science.gov (United States)

Bongiorni, Silvia; Tilesi, Francesca; Bicorgna, Silvia; Iacoponi, Francesca; Willems, Daniela; Gargani, Maria; D'Andrea, MariaSilvia; Pilla, Fabio; Valentini, Alessio

2014-11-07

Success of meat production and selection for improvement of meat quality is among the primary aims in animal production. Meat quality traits are economically important in swine; however, the underlying genetic nature is very complex. Therefore, an improved pork production strongly depends on identifying and studying how genetic variations contribute to modulate gene expression. Promoters are key regions in gene modulation as they harbour several binding motifs to transcription regulatory factors. Therefore, polymorphisms in these regions are likely to deeply affect RNA levels and consequently protein synthesis. In this study, we report the identification of single nucleotide polymorphisms (SNPs) in promoter regions of candidate genes involved in development, cellular differentiation and muscle growth in Sus scrofa. We identified SNPs in the promoter regions of genes belonging to the Myogenic Regulatory Factors (MRF) gene family (the Myogenic Differentiation gene, MYOD1) and to Growth and Differentiation Factors (GDF) gene family (Myostatin gene, MSTN, GDF8), in Casertana and Large White breeds. The purpose of this study was to investigate if polymorphisms in the promoters could affect the transcriptional activity of these genes. With this aim, we evaluated in vitro the functional activity of the luciferase reporter gene luc2 activity, driven by two constructs carrying different promoter haplotypes. We tested the effects of the G302A (U12574) transition on the promoter efficiency in MYOD1 gene. We ascertained a difference in transcription efficiency for the two variants. A stronger activity of the A-carrying construct is more evident in C2C12. The luciferase expression driven by the MYOD1-A allelic variant displayed a 3.8-fold increased transcriptional activity. We investigated the activity of two haplotype variants (AY527152) in the promoter of GDF8 gene. The haploptype-1 (A435-A447-A879) up-regulated the expression of the reporter gene by a two-fold increase, and

Human sex hormone-binding globulin gene expression- multiple promoters and complex alternative splicing

Directory of Open Access Journals (Sweden)

Rosner William

2009-05-01

Full Text Available Abstract Background Human sex hormone-binding globulin (SHBG regulates free sex steroid concentrations in plasma and modulates rapid, membrane based steroid signaling. SHBG is encoded by an eight exon-long transcript whose expression is regulated by a downstream promoter (PL. The SHBG gene was previously shown to express a second major transcript of unknown function, derived from an upstream promoter (PT, and two minor transcripts. Results We report that transcriptional expression of the human SHBG gene is far more complex than previously described. PL and PT direct the expression of at least six independent transcripts each, resulting from alternative splicing of exons 4, 5, 6, and/or 7. We mapped two transcriptional start sites downstream of PL and PT, and present evidence for a third SHBG gene promoter (PN within the neighboring FXR2 gene; PN regulates the expression of at least seven independent SHBG gene transcripts, each possessing a novel, 164-nt first exon (1N. Transcriptional expression patterns were generated for human prostate, breast, testis, liver, and brain, and the LNCaP, MCF-7, and HepG2 cell lines. Each expresses the SHBG transcript, albeit in varying abundance. Alternative splicing was more pronounced in the cancer cell lines. PL- PT- and PN-derived transcripts were most abundant in liver, testis, and prostate, respectively. Initial findings reveal the existence of a smaller immunoreactive SHBG species in LNCaP, MCF-7, and HepG2 cells. Conclusion These results extend our understanding of human SHBG gene transcription, and raise new and important questions regarding the role of novel alternatively spliced transcripts, their function in hormonally responsive tissues including the breast and prostate, and the role that aberrant SHBG gene expression may play in cancer.

Highly specific expression of luciferase gene in lungs of naive nude mice directed by prostate-specific antigen promoter

International Nuclear Information System (INIS)

Li Hongwei; Li Jinzhong; Helm, Gregory A.; Pan Dongfeng

2005-01-01

PSA promoter has been demonstrated the utility for tissue-specific toxic gene therapy in prostate cancer models. Characterization of foreign gene overexpression in normal animals elicited by PSA promoter should help evaluate therapy safety. Here we constructed an adenovirus vector (AdPSA-Luc), containing firefly luciferase gene under the control of the 5837 bp long prostate-specific antigen promoter. A charge coupled device video camera was used to non-invasively image expression of firefly luciferase in nude mice on days 3, 7, 11 after injection of 2 x 10 9 PFU of AdPSA-Luc virus via tail vein. The result showed highly specific expression of the luciferase gene in lungs of mice from day 7. The finding indicates the potential limitations of the suicide gene therapy of prostate cancer based on selectivity of PSA promoter. By contrary, it has encouraging implications for further development of vectors via PSA promoter to enable gene therapy for pulmonary diseases

Control of phenylalanine ammonia-lyase gene promoters from pea by UV radiation

International Nuclear Information System (INIS)

Pluskota, W.E.; Michalczyk, D.J.; Gorecki, R.J.

2005-01-01

The gene fusion system was used to study UV light-control of PS PAL1 and PS PAL2 genes encoding phenylalanine ammonia-lyase of pea. The induction of pea PAL promoters was analysed in transgenic tobacco plants. Binary plasmids (derivatives of pBI101.2 vector) containing 5' regulatory fragments of PS PAL1 and PS PAL2 linked to reporter genes (GUS, LUC) were constructed. The analyses were performed with the use of single constructs (containing one variant of PS PAL promoter and one reporter gene) and dual constructs (containing both PS PAL1 and PS PAL2 promoters connected with different reporter genes). The use of dual constructs enabled the evaluation of both PS PAL promoters activity in the same plant. The analyses of in vitro grown plants have shown that both PAL promoters are strongly induced in leaves subjected to UV radiation. In some cases, the UV-stimulated expression exceeded the exposed areas. This phenomenon was observed more often in the leaves of plants containing the PS PAL1::GUS than PS PAL2::GUS construct. Removal of boxes 2, 4, 5 from PS PAL1 promoter and deletion of its 5' end region (-339 to -1394) decreases the level of gene expression but does not eliminate its responsiveness to UV

The altered promoter methylation of oxytocin receptor gene in autism.

Science.gov (United States)

Elagoz Yuksel, Mine; Yuceturk, Betul; Karatas, Omer Faruk; Ozen, Mustafa; Dogangun, Burak

Autism spectrum disorder (ASD) is one of the lifelong existing disorders. Abnormal methylation status of gene promoters of oxytonergic system has been implicated as among the etiologic factors of ASDs. We, therefore, investigated the methylation frequency of oxytocin receptor gene (OXTR) promoter from peripheral blood samples of children with autistic features. Our sample includes 66 children in total (22-94 months); 27 children with ASDs according to the DSM-IV-TR and the Childhood Autism Rating Scale (CARS) and 39 children who do not have any autistic like symptoms as the healthy control group. We investigated the DNA methylation status of OXTR promoter by methylation specific enzymatic digestion of genomic DNA and polymerase chain reaction. A significant relationship has been found between ASDs and healthy controls for the reduction of methylation frequency of the regions MT1 and MT3 of OXTR. We could not find any association in the methylation frequency of MT2 and MT4 regions of OXTR. Although our findings indicate high frequency of OXTR promoter hypomethylation in ASDs, there is need for independent replication of the results for a bigger sample set. We expect that future studies with the inclusion of larger, more homogeneous samples will attempt to disentangle the causes of ASDs.

Cardiac-Specific Gene Expression Facilitated by an Enhanced Myosin Light Chain Promoter

Directory of Open Access Journals (Sweden)

Wolfgang Boecker

2004-04-01

Full Text Available Background: Adenoviral gene transfer has been shown to be effective in cardiac myocytes in vitro and in vivo. A major limitation of myocardial gene therapy is the extracardiac transgene expression. Methods: To minimize extracardiac gene expression, we have constructed a tissue-specific promoter for cardiac gene transfer, namely, the 250-bp fragment of the myosin light chain-2v (MLC-2v gene, which is known to be expressed in a tissue-specific manner in ventricular myocardium followed by a luciferase (luc reporter gene (Ad.4 × MLC250.Luc. Rat cardiomyocytes, liver and kidney cells were infected with Ad.4 × MLC.Luc or control vectors. For in vivo testing, Ad.4 × MLC250.Luc was injected into the myocardium or in the liver of rats. Kinetics of promoter activity were monitored over 8 days using a cooled CCD camera. Results: In vitro: By infecting hepatic versus cardiomyocyte cells, we found that the promoter specificity ratio (luc activity in cardiomyocytes per liver cells was 20.4 versus 0.9 (Ad.4 × MLC250.Luc vs. Ad.CMV. In vivo: Ad.4 × MLC250.Luc significantly reduced luc activity in liver (38.4-fold, lung (16.1-fold, and kidney (21.8-fold versus Ad.CMV (p = .01; whereas activity in the heart was only 3.8-fold decreased. The gene expression rate of cardiomyocytes versus hepatocytes was 7:1 (Ad.4 × MLC.Luc versus 1:1.4 (Ad.CMV.Luc. Discussion: This new vector may be useful to validate therapeutic approaches in animal disease models and offers the perspective for selective expression of therapeutic genes in the diseased heart.

Effect of TNFα on activities of different promoters of human apolipoprotein A-I gene

International Nuclear Information System (INIS)

Orlov, Sergey V.; Mogilenko, Denis A.; Shavva, Vladimir S.; Dizhe, Ella B.; Ignatovich, Irina A.; Perevozchikov, Andrej P.

2010-01-01

Research highlights: → TNFα stimulates the distal alternative promoter of human apoA-I gene. → TNFα acts by weakening of promoter competition within apoA-I gene (promoter switching). → MEK1/2 and nuclear receptors PPARα and LXRs take part in apoA-I promoter switching. -- Abstract: Human apolipoprotein A-I (ApoA-I) is a major structural and functional protein component of high-density lipoproteins. The expression of the apolipoprotein A-I gene (apoA-I) in hepatocytes is repressed by pro-inflammatory cytokines such as IL-1β and TNFα. Recently, two novel additional (alternative) promoters for human apoA-I gene have been identified. Nothing is known about the role of alternative promoters in TNFα-mediated downregulation of apoA-I gene. In this article we report for the first time about the different effects of TNFα on two alternative promoters of human apoA-I gene. Stimulation of HepG2 cells by TNFα leads to activation of the distal alternative apoA-I promoter and downregulation of the proximal alternative and the canonical apoA-I promoters. This effect is mediated by weakening of the promoter competition within human apoA-I 5'-regulatory region (apoA-I promoter switching) in the cells treated by TNFα. The MEK1/2-ERK1/2 cascade and nuclear receptors PPARα and LXRs are important for TNFα-mediated apoA-I promoter switching.

Isolation and characterization of a copalyl diphosphate synthase gene promoter from Salvia miltiorrhiza

Directory of Open Access Journals (Sweden)

Piotr Szymczyk

2016-09-01

Full Text Available The promoter, 5' UTR, and 34-nt 5' fragments of protein encoding region of the Salvia miltiorrhiza copalyl diphosphate synthase gene were cloned and characterized. No tandem repeats, miRNA binding sites, or CpNpG islands were observed in the promoter, 5' UTR, or protein encoding fragments. The entire isolated promoter and 5' UTR is 2235 bp long and contains repetitions of many cis-active elements, recognized by homologous transcription factors, found in Arabidopsis thaliana and other plant species. A pyrimidine-rich fragment with only 6 non-pyrimidine bases was localized in the 33-nt stretch from nt 2185 to 2217 in the 5' UTR. The observed cis-active sequences are potential binding sites for trans-factors that could regulate spatio-temporal CPS gene expression in response to biotic and abiotic stress conditions. Obtained results are initially verified by in silico and co-expression studies based on A. thaliana microarray data. The quantitative RT-PCR analysis confirmed that the entire 2269-bp copalyl diphosphate synthase gene fragment has the promoter activity. Quantitative RT-PCR analysis was used to study changes in CPS promoter activity occurring in response to the application of four selected biotic and abiotic regulatory factors; auxin, gibberellin, salicylic acid, and high-salt concentration.

Analysis of an osmotically regulated pathogenesis-related osmotin gene promoter.

Science.gov (United States)

Raghothama, K G; Liu, D; Nelson, D E; Hasegawa, P M; Bressan, R A

1993-12-01

Osmotin is a small (24 kDa), basic, pathogenesis-related protein, that accumulates during adaptation of tobacco (Nicotiana tabacum) cells to osmotic stress. There are more than 10 inducers that activate the osmotin gene in various plant tissues. The osmotin promoter contains several sequences bearing a high degree of similarity to ABRE, as-1 and E-8 cis element sequences. Gel retardation studies indicated the presence of at least two regions in the osmotin promoter that show specific interactions with nuclear factors isolated from cultured cells or leaves. The abundance of these binding factors increased in response to salt, ABA and ethylene. Nuclear factors protected a 35 bp sequence of the promoter from DNase I digestion. Different 5' deletions of the osmotin promoter cloned into a promoter-less GUSNOS plasmid (pBI 201) were used in transient expression studies with a Biolistic gun. The transient expression studies revealed the presence of three distinct regions in the osmotin promoter. The promoter sequence from -108 to -248 bp is absolutely required for reporter gene activity, followed by a long stretch (up to -1052) of enhancer-like sequence and then a sequence upstream of -1052, which appears to contain negative elements. The responses to ABA, ethylene, salt, desiccation and wounding appear to be associated with the -248 bp sequence of the promoter. This region also contains a putative ABRE (CACTGTG) core element. Activation of the osmotin gene by various inducers is discussed in view of antifungal activity of the osmotin protein.

Gene Expression in Class 2 Integrons Is SOS-Independent and Involves Two Pc Promoters.

Science.gov (United States)

Jové, Thomas; Da Re, Sandra; Tabesse, Aurore; Gassama-Sow, Amy; Ploy, Marie-Cécile

2017-01-01

Integrons are powerful bacterial genetic elements that permit the expression and dissemination of antibiotic-resistance gene cassettes. They contain a promoter Pc that allows the expression of gene cassettes captured through site-specific recombination catalyzed by IntI, the integron-encoded integrase. Class 1 and 2 integrons are found in both clinical and environmental settings. The regulation of intI and of Pc promoters has been extensively studied in class 1 integrons and the regulatory role of the SOS response on intI expression has been shown. Here we investigated class 2 integrons. We characterized the P intI2 promoter and showed that intI2 expression is not regulated via the SOS response. We also showed that, unlike class 1 integrons, class 2 integrons possess not one but two active Pc promoters that are located within the attI2 region that seem to contribute equally to gene cassette expression. Class 2 integrons mostly encode an inactive truncated integrase, but the rare class 2 integrons that encode an active integrase are associated with less efficient Pc2 promoter variants. We propose an evolutionary model for class 2 integrons in which the absence of repression of the integrase gene expression led to mutations resulting in either inactive integrase or Pc variants of weaker activity, thereby reducing the potential fitness cost of these integrons.

Regional differences in gene expression and promoter usage in aged human brains

KAUST Repository

Pardo, Luba M.

2013-02-19

To characterize the promoterome of caudate and putamen regions (striatum), frontal and temporal cortices, and hippocampi from aged human brains, we used high-throughput cap analysis of gene expression to profile the transcription start sites and to quantify the differences in gene expression across the 5 brain regions. We also analyzed the extent to which methylation influenced the observed expression profiles. We sequenced more than 71 million cap analysis of gene expression tags corresponding to 70,202 promoter regions and 16,888 genes. More than 7000 transcripts were differentially expressed, mainly because of differential alternative promoter usage. Unexpectedly, 7% of differentially expressed genes were neurodevelopmental transcription factors. Functional pathway analysis on the differentially expressed genes revealed an overrepresentation of several signaling pathways (e.g., fibroblast growth factor and wnt signaling) in hippocampus and striatum. We also found that although 73% of methylation signals mapped within genes, the influence of methylation on the expression profile was small. Our study underscores alternative promoter usage as an important mechanism for determining the regional differences in gene expression at old age.

A novel binary T-vector with the GFP reporter gene for promoter characterization.

Directory of Open Access Journals (Sweden)

Shu-Ye Jiang

Full Text Available Several strategies have been developed to clone PCR fragments into desired vectors. However, most of commercially available T-vectors are not binary vectors and cannot be directly used for Agrobacterium-mediated plant genetic transformation. In this study, a novel binary T-vector was constructed by integrating two AhdI restriction sites into the backbone vector pCAMBIA 1300. The T-vector also contains a GFP reporter gene and thus, can be used to analyze promoter activity by monitoring the reporter gene. On the other hand, identification and characterization of various promoters not only benefit the functional annotation of their genes but also provide alternative candidates to be used to drive interesting genes for plant genetic improvement by transgenesis. More than 1,000 putative pollen-specific rice genes have been identified in a genome-wide level. Among them, 67 highly expressed genes were further characterized. One of the pollen-specific genes LOC_Os10g35930 was further surveyed in its expression patterns with more details by quantitative real-time reverse-transcription PCR (qRT-PCR analysis. Finally, its promoter activity was further investigated by analyzing transgenic rice plants carrying the promoter::GFP cassette, which was constructed from the newly developed T-vector. The reporter GFP gene expression in these transgenic plants showed that the promoter was active only in mature but not in germinated pollens.

NGX6 gene mediated by promoter methylation as a potential molecular marker in colorectal cancer

Directory of Open Access Journals (Sweden)

Shen Shourong

2010-04-01

Full Text Available Abstract Background Nasopharyngeal carcinoma associated gene 6 (NGX6 is down-regulated in most colon cancer cell lines and tumor tissues when compared with their normal tissue samples. As a novel suppress tumor gene, it could inhibit colon cancer cell growth and cell cycle progression. However, little is known about the transcriptional mechanisms controlling NGX6 gene expression. Recent findings suggest that epigenetic inactivation of multiple tumor suppressor genes plays an important role in the tumorigenesis of colorectal carcinoma (CRC. In this study, we explored the role of DNA methylation in regulation of NGX6 transcription. Methods In the present study, we cloned the NGX6 promoter with characteristics of a CpG island by luciferase reporter assay. Then, the CpG methylation status around the NGX6 promoter region in colon cancer cell lines and colorectal tumor tissues was examined by methylation-specific PCR and bisulfite DNA sequencing. Finally, 5-Aza-2'-deoxycytidine (5-Aza-dC treatment was used to confirm the correlation between NGX6 promoter methylation and its gene inactivation. Results The sequence spanning positions -157 to +276 was identified as the NGX6 promoter, in which no canonical TATA boxes were found, while two CAAT boxes and GC boxes were discovered. Methylation status was observed more frequently in 40 colorectal cancer samples than in 40 adjacent normal mucosa samples (18/40 versus 7/40; P Conclusions Down-regulation of NGX6 gene is related to the promoter methylation. DNA methylation of NGX6 promoter might be a potential molecular marker for diagnosis or prognosis, or serve as a therapeutic target.

Transactivation of the proximal promoter of human oxytocin gene by TR4 orphan receptor

International Nuclear Information System (INIS)

Wang, C.-P.; Lee, Y.-F.; Chang, C.; Lee, H.-J.

2006-01-01

The human testicular receptor 4 (TR4) shares structural homology with members of the nuclear receptor superfamily. Some other members of this superfamily were able to regulate the transcriptional activity of the human oxytocin (OXT) promoter by binding to the first DR0 regulatory site. However, little investigation was conducted systematically in the study of the second dDR4 site of OXT proximal promoter, and the relationship between the first and the second sites of OXT promoter. Here, we demonstrated for the first time that TR4 could increase the proximal promoter activity of the human OXT gene via DR0, dDR4, and OXT (both DR0 and dDR4) elements, respectively. TR4 might induce OXT gene expression through the OXT element in a dose-dependent manner. However, there is no synergistic effect between DR0 and dDR4 elements during TR4 transactivation. Taken together, these results suggested that TR4 should be one of important regulators of OXT gene expression

hTERT promoter mediating gene therapy in laryngeal squamous carcinomas cells in vitro

International Nuclear Information System (INIS)

Liao Zhengkai; Zhou Yunfeng; Zhou Fuxiang; Luo Zhiguo; Xiong Jie; Bao Jie; Xie Conghua; Liu Shiquan

2007-01-01

Objective: To investigate the relationship among hTERT promoter activity, hTERT mRNA expression, and telomerase activity (TA) in laryngeal squamous carcinomas cell lines, and to evaluate the usefulness of hTERT promoter mediated gene therapy. Methods: After plasmids pGL3-hTERTp were transfected, hTEBT promoter activity, hTERT mRNA expression and TA were determined by luciferase assay, RT-PCR and TRAP-PCR-ELISA, respectively. Plasmid phTERTp-HRP was constructed and transfected, HRP expression was determined by RT-PCR and competent peroxidase activity was confirmed by enzyme activity assay. The cytotoxicity and radiosensitivity of phTERTp-HRP/IAA were determined by clonogenic assay. Results: The relative levels of hTERT promoter activity, hTERT mRNA expression and TA in Hep2R cells were 1.37-fold, 1.43-fold and 1.81-fold compared with Hep2R cells, hTERT promoter activity was closely associated with hTERT mRNA expression and TA levels (P SF 2 ) was 1.24 (Hep2R cells) and 1.20 (Hep 2cells), the parameter a of with or without IAA incubation were 0.090, 0.020 (Hep2R)and 0.099, 0.042 (Hep2). Conclusions: hTERT promoter is applicable in mediating gene therapy in different radiosensitive laryngeal squamous carcinomas cells. hTERTp-HRP/IAA gene therapy may be a promising supplementary method for radiotherapy of laryngeal squamous-cell carcinomas. (authors)

DNA entropy reveals a significant difference in complexity between housekeeping and tissue specific gene promoters.

Science.gov (United States)

Thomas, David; Finan, Chris; Newport, Melanie J; Jones, Susan

2015-10-01

The complexity of DNA can be quantified using estimates of entropy. Variation in DNA complexity is expected between the promoters of genes with different transcriptional mechanisms; namely housekeeping (HK) and tissue specific (TS). The former are transcribed constitutively to maintain general cellular functions, and the latter are transcribed in restricted tissue and cells types for specific molecular events. It is known that promoter features in the human genome are related to tissue specificity, but this has been difficult to quantify on a genomic scale. If entropy effectively quantifies DNA complexity, calculating the entropies of HK and TS gene promoters as profiles may reveal significant differences. Entropy profiles were calculated for a total dataset of 12,003 human gene promoters and for 501 housekeeping (HK) and 587 tissue specific (TS) human gene promoters. The mean profiles show the TS promoters have a significantly lower entropy (pentropy distributions for the 3 datasets show that promoter entropies could be used to identify novel HK genes. Functional features comprise DNA sequence patterns that are non-random and hence they have lower entropies. The lower entropy of TS gene promoters can be explained by a higher density of positive and negative regulatory elements, required for genes with complex spatial and temporary expression. Copyright © 2015 Elsevier Ltd. All rights reserved.

Duodenal ulcer promoting gene of Helicobacter pylori.

Science.gov (United States)

Lu, Hong; Hsu, Ping-I; Graham, David Y; Yamaoka, Yoshio

2005-04-01

Identification of a disease-specific H pylori virulence factors predictive of the outcome of infection remains unachieved. We used the polymerase chain reaction and Southern blot to compare the presence of 14 vir homologue genes with clinical presentation of H pylori infection, mucosal histology, and mucosal interleukin (IL)-8 levels. We examined 500 H pylori strains from East Asia and South America, including 120 with gastritis, 140 with duodenal ulcer (DU), 110 with gastric ulcer (GU), and 130 with gastric cancer. Only 1 gene that encompassed both jhp0917 and jhp0918 called dupA (duodenal ulcer promoting gene) was associated with a specific clinical outcome. dupA was present in 42% of DU vs. 21% of gastritis (adjusted odds ratio [OR] = 3.1, 95% confidence interval [CI]: 1.7-5.7). Its presence was also associated with more intense antral neutrophil infiltration and IL-8 levels and was a marker for protection against gastric atrophy, intestinal metaplasia, and gastric cancer (OR for gastric cancer = 0.42, 95% CI: 0.2-0.9 compared with gastritis). In vitro studies in gastric epithelial cells using dupA -deleted and -complemented mutants showed that the dupA plays roles in IL-8 production, in activation of transcription factors responsible for IL-8 promoter activity, and in increased survivability at low pH. dupA is a novel marker associated with an increased risk for DU and reduced risk for gastric atrophy and cancer. Its association with DU-promoting and -protective effects against atrophy/cancer was evident in both Asian and Western countries.

Promoter Analysis Reveals Globally Differential Regulation of Human Long Non-Coding RNA and Protein-Coding Genes

KAUST Repository

Alam, Tanvir

2014-10-02

Transcriptional regulation of protein-coding genes is increasingly well-understood on a global scale, yet no comparable information exists for long non-coding RNA (lncRNA) genes, which were recently recognized to be as numerous as protein-coding genes in mammalian genomes. We performed a genome-wide comparative analysis of the promoters of human lncRNA and protein-coding genes, finding global differences in specific genetic and epigenetic features relevant to transcriptional regulation. These two groups of genes are hence subject to separate transcriptional regulatory programs, including distinct transcription factor (TF) proteins that significantly favor lncRNA, rather than coding-gene, promoters. We report a specific signature of promoter-proximal transcriptional regulation of lncRNA genes, including several distinct transcription factor binding sites (TFBS). Experimental DNase I hypersensitive site profiles are consistent with active configurations of these lncRNA TFBS sets in diverse human cell types. TFBS ChIP-seq datasets confirm the binding events that we predicted using computational approaches for a subset of factors. For several TFs known to be directly regulated by lncRNAs, we find that their putative TFBSs are enriched at lncRNA promoters, suggesting that the TFs and the lncRNAs may participate in a bidirectional feedback loop regulatory network. Accordingly, cells may be able to modulate lncRNA expression levels independently of mRNA levels via distinct regulatory pathways. Our results also raise the possibility that, given the historical reliance on protein-coding gene catalogs to define the chromatin states of active promoters, a revision of these chromatin signature profiles to incorporate expressed lncRNA genes is warranted in the future.

Co-expression of interleukin 12 enhances antitumor effects of a novel chimeric promoter-mediated suicide gene therapy in an immunocompetent mouse model

International Nuclear Information System (INIS)

Xu, Yu; Liu, Zhengchun; Kong, Haiyan; Sun, Wenjie; Liao, Zhengkai; Zhou, Fuxiang; Xie, Conghua

2011-01-01

Highlights: → A novel chimeric promoter consisting of CArG element and hTERT promoter was developed. → The promoter was characterized with radiation-inducibility and tumor-specificity. → Suicide gene system driven by the promoter showed remarkable cytotoxicity in vitro. → Co-expression of IL12 enhanced the promoter mediated suicide gene therapy in vivo. -- Abstract: The human telomerase reverse transcriptase (hTERT) promoter has been widely used in target gene therapy of cancer. However, low transcriptional activity limited its clinical application. Here, we designed a novel dual radiation-inducible and tumor-specific promoter system consisting of CArG elements and the hTERT promoter, resulting in increased expression of reporter genes after gamma-irradiation. Therapeutic and side effects of adenovirus-mediated horseradish peroxidase (HRP)/indole-3-acetic (IAA) system downstream of the chimeric promoter were evaluated in mice bearing Lewis lung carcinoma, combining with or without adenovirus-mediated interleukin 12 (IL12) gene driven by the cytomegalovirus promoter. The combination treatment showed more effective suppression of tumor growth than those with single agent alone, being associated with pronounced intratumoral T-lymphocyte infiltration and minor side effects. Our results suggest that the combination treatment with HRP/IAA system driven by the novel chimeric promoter and the co-expression of IL12 might be an effective and safe target gene therapy strategy of cancer.

Co-expression of interleukin 12 enhances antitumor effects of a novel chimeric promoter-mediated suicide gene therapy in an immunocompetent mouse model

Energy Technology Data Exchange (ETDEWEB)

Xu, Yu, E-mail: xuyu1001@gmail.com [Department of Radiation and Medical Oncology, Zhongnan Hospital of Wuhan University, 169 Donghu Road, Wuhan 430071 (China); Hubei Key Laboratory of Tumor Biological Behaviors and Hubei Cancer Clinical Study Center, 169 Donghu Road, Wuhan 430071 (China); Liu, Zhengchun, E-mail: l135027@126.com [Hubei Key Laboratory of Tumor Biological Behaviors and Hubei Cancer Clinical Study Center, 169 Donghu Road, Wuhan 430071 (China); Kong, Haiyan, E-mail: suppleant@163.com [Hubei Key Laboratory of Tumor Biological Behaviors and Hubei Cancer Clinical Study Center, 169 Donghu Road, Wuhan 430071 (China); Sun, Wenjie, E-mail: wendy11240325@163.com [Department of Radiation and Medical Oncology, Zhongnan Hospital of Wuhan University, 169 Donghu Road, Wuhan 430071 (China); Hubei Key Laboratory of Tumor Biological Behaviors and Hubei Cancer Clinical Study Center, 169 Donghu Road, Wuhan 430071 (China); Liao, Zhengkai, E-mail: fastbeta@gmail.com [Department of Radiation and Medical Oncology, Zhongnan Hospital of Wuhan University, 169 Donghu Road, Wuhan 430071 (China); Hubei Key Laboratory of Tumor Biological Behaviors and Hubei Cancer Clinical Study Center, 169 Donghu Road, Wuhan 430071 (China); Zhou, Fuxiang, E-mail: happyzhoufx@sina.com [Department of Radiation and Medical Oncology, Zhongnan Hospital of Wuhan University, 169 Donghu Road, Wuhan 430071 (China); Hubei Key Laboratory of Tumor Biological Behaviors and Hubei Cancer Clinical Study Center, 169 Donghu Road, Wuhan 430071 (China); Xie, Conghua, E-mail: chxie_65@hotmail.com [Department of Radiation and Medical Oncology, Zhongnan Hospital of Wuhan University, 169 Donghu Road, Wuhan 430071 (China); Hubei Key Laboratory of Tumor Biological Behaviors and Hubei Cancer Clinical Study Center, 169 Donghu Road, Wuhan 430071 (China); and others

2011-09-09

Highlights: {yields} A novel chimeric promoter consisting of CArG element and hTERT promoter was developed. {yields} The promoter was characterized with radiation-inducibility and tumor-specificity. {yields} Suicide gene system driven by the promoter showed remarkable cytotoxicity in vitro. {yields} Co-expression of IL12 enhanced the promoter mediated suicide gene therapy in vivo. -- Abstract: The human telomerase reverse transcriptase (hTERT) promoter has been widely used in target gene therapy of cancer. However, low transcriptional activity limited its clinical application. Here, we designed a novel dual radiation-inducible and tumor-specific promoter system consisting of CArG elements and the hTERT promoter, resulting in increased expression of reporter genes after gamma-irradiation. Therapeutic and side effects of adenovirus-mediated horseradish peroxidase (HRP)/indole-3-acetic (IAA) system downstream of the chimeric promoter were evaluated in mice bearing Lewis lung carcinoma, combining with or without adenovirus-mediated interleukin 12 (IL12) gene driven by the cytomegalovirus promoter. The combination treatment showed more effective suppression of tumor growth than those with single agent alone, being associated with pronounced intratumoral T-lymphocyte infiltration and minor side effects. Our results suggest that the combination treatment with HRP/IAA system driven by the novel chimeric promoter and the co-expression of IL12 might be an effective and safe target gene therapy strategy of cancer.

The application of powerful promoters to enhance gene expression in industrial microorganisms.

Science.gov (United States)

Zhou, Shenghu; Du, Guocheng; Kang, Zhen; Li, Jianghua; Chen, Jian; Li, Huazhong; Zhou, Jingwen

2017-02-01

Production of useful chemicals by industrial microorganisms has been attracting more and more attention. Microorganisms screened from their natural environment usually suffer from low productivity, low stress resistance, and accumulation of by-products. In order to overcome these disadvantages, rational engineering of microorganisms to achieve specific industrial goals has become routine. Rapid development of metabolic engineering and synthetic biology strategies provide novel methods to improve the performance of industrial microorganisms. Rational regulation of gene expression by specific promoters is essential to engineer industrial microorganisms for high-efficiency production of target chemicals. Identification, modification, and application of suitable promoters could provide powerful switches at the transcriptional level for fine-tuning of a single gene or a group of genes, which are essential for the reconstruction of pathways. In this review, the characteristics of promoters from eukaryotic, prokaryotic, and archaea microorganisms are briefly introduced. Identification of promoters based on both traditional biochemical and systems biology routes are summarized. Besides rational modification, de novo design of promoters to achieve gradient, dynamic, and logic gate regulation are also introduced. Furthermore, flexible application of static and dynamic promoters for the rational engineering of industrial microorganisms is highlighted. From the perspective of powerful promoters in industrial microorganisms, this review will provide an extensive description of how to regulate gene expression in industrial microorganisms to achieve more useful goals.

Altered gene-expression profile in rat plasma and promoted body ...

African Journals Online (AJOL)

Altered gene-expression profile in rat plasma and promoted body and brain development ... The study was aimed to explore how the prenatal EE impacts affect the ... positively promote the body and nervous system development of offspring, ...

Plutella xylostella granulovirus late gene promoter activity in the context of the Autographa californica multiple nucleopolyhedrovirus genome.

Science.gov (United States)

Ren, He-Lin; Hu, Yuan; Guo, Ya-Jun; Li, Lu-Lin

2016-06-01

Within Baculoviridae, little is known about the molecular mechanisms of replication in betabaculoviruses, despite extensive studies in alphabaculoviruses. In this study, the promoters of nine late genes of the betabaculovirus Plutella xylostella granulovirus (PlxyGV) were cloned into a transient expression vector and the alphabaculovirus Autographa californica multiple nucleopolyhedrovirus (AcMNPV) genome, and compared with homologous late gene promoters of AcMNPV in Sf9 cells. In transient expression assays, all PlxyGV late promoters were activated in cells transfected with the individual reporter plasmids together with an AcMNPV bacmid. In infected cells, reporter gene expression levels with the promoters of PlxyGV e18 and AcMNPV vp39 and gp41 were significantly higher than those of the corresponding AcMNPV or PlxyGV promoters, which had fewer late promoter motifs. Observed expression levels were lower for the PlxyGV p6.9, pk1, gran, p10a, and p10b promoters than for the corresponding AcMNPV promoters, despite equal numbers of late promoter motifs, indicating that species-specific elements contained in some late promoters were favored by the native viral RNA polymerases for optimal transcription. The 8-nt sequence TAAATAAG encompassing the ATAAG motif was conserved in the AcMNPV polh, p10, and pk1 promoters. The 5-nt sequence CAATT located 4 or 5 nt upstream of the T/ATAAG motif was conserved in the promoters of PlxyGV gran, p10c, and pk1. The results of this study demonstrated that PlxyGV late gene promoters could be effectively activated by the RNA polymerase from AcMNPV, implying that late gene expression systems are regulated by similar mechanisms in alphabaculoviruses and betabaculoviruses.

Finding Combination of Features from Promoter Regions for Ovarian Cancer-related Gene Group Classification

KAUST Repository

Olayan, Rawan S.

2012-01-01

In classification problems, it is always important to use the suitable combination of features that will be employed by classifiers. Generating the right combination of features usually results in good classifiers. In the situation when the problem is not well understood, data items are usually described by many features in the hope that some of these may be the relevant or most relevant ones. In this study, we focus on one such problem related to genes implicated in ovarian cancer (OC). We try to recognize two important OC-related gene groups: oncogenes, which support the development and progression of OC, and oncosuppressors, which oppose such tendencies. For this, we use the properties of promoters of these genes. We identified potential “regulatory features” that characterize OC-related oncogenes and oncosuppressors promoters. In our study, we used 211 oncogenes and 39 oncosuppressors. For these, we identified 538 characteristic sequence motifs from their promoters. Promoters are annotated by these motifs and derived feature vectors used to develop classification models. We made a comparison of a number of classification models in their ability to distinguish oncogenes from oncosuppressors. Based on 10-fold cross-validation, the resultant model was able to separate the two classes with sensitivity of 96% and specificity of 100% with the complete set of features. Moreover, we developed another recognition model where we attempted to distinguish oncogenes and oncosuppressors as one group from other OC-related genes. That model achieved accuracy of 82%. We believe that the results of this study will help in discovering other OC-related oncogenes and oncosuppressors not identified as yet.

Finding Combination of Features from Promoter Regions for Ovarian Cancer-related Gene Group Classification

KAUST Repository

Olayan, Rawan S.

2012-12-01

In classification problems, it is always important to use the suitable combination of features that will be employed by classifiers. Generating the right combination of features usually results in good classifiers. In the situation when the problem is not well understood, data items are usually described by many features in the hope that some of these may be the relevant or most relevant ones. In this study, we focus on one such problem related to genes implicated in ovarian cancer (OC). We try to recognize two important OC-related gene groups: oncogenes, which support the development and progression of OC, and oncosuppressors, which oppose such tendencies. For this, we use the properties of promoters of these genes. We identified potential “regulatory features” that characterize OC-related oncogenes and oncosuppressors promoters. In our study, we used 211 oncogenes and 39 oncosuppressors. For these, we identified 538 characteristic sequence motifs from their promoters. Promoters are annotated by these motifs and derived feature vectors used to develop classification models. We made a comparison of a number of classification models in their ability to distinguish oncogenes from oncosuppressors. Based on 10-fold cross-validation, the resultant model was able to separate the two classes with sensitivity of 96% and specificity of 100% with the complete set of features. Moreover, we developed another recognition model where we attempted to distinguish oncogenes and oncosuppressors as one group from other OC-related genes. That model achieved accuracy of 82%. We believe that the results of this study will help in discovering other OC-related oncogenes and oncosuppressors not identified as yet.

Integration of molecular biology tools for identifying promoters and genes abundantly expressed in flowers of Oncidium Gower Ramsey

Directory of Open Access Journals (Sweden)

Tung Shu-Yun

2011-04-01

Full Text Available Abstract Background Orchids comprise one of the largest families of flowering plants and generate commercially important flowers. However, model plants, such as Arabidopsis thaliana do not contain all plant genes, and agronomic and horticulturally important genera and species must be individually studied. Results Several molecular biology tools were used to isolate flower-specific gene promoters from Oncidium 'Gower Ramsey' (Onc. GR. A cDNA library of reproductive tissues was used to construct a microarray in order to compare gene expression in flowers and leaves. Five genes were highly expressed in flower tissues, and the subcellular locations of the corresponding proteins were identified using lip transient transformation with fluorescent protein-fusion constructs. BAC clones of the 5 genes, together with 7 previously published flower- and reproductive growth-specific genes in Onc. GR, were identified for cloning of their promoter regions. Interestingly, 3 of the 5 novel flower-abundant genes were putative trypsin inhibitor (TI genes (OnTI1, OnTI2 and OnTI3, which were tandemly duplicated in the same BAC clone. Their promoters were identified using transient GUS reporter gene transformation and stable A. thaliana transformation analyses. Conclusions By combining cDNA microarray, BAC library, and bombardment assay techniques, we successfully identified flower-directed orchid genes and promoters.

Spermatogenesis-related ring finger gene ZNF230 promoter: identification and functional analysis

DEFF Research Database (Denmark)

Xu, Wenming; Zhang, Sizhong; Qiu, Weimin

2009-01-01

reporter Plasmids. Overexpression and site-directed mutation test were used to characterize the cis-element. The results showed ZNF230 gene promoter to be GC rich and not contain a TATA box. Deletion analysis of the 5'-flanking region of ZNF230 in HEK293 cells indicated that the sequence encompassing from...... nt -131 to +152 has a basal transcriptional activity. Site-directed mutation test and mithramycin A treatment demonstrated that the ZNF230 promoter contained a functional Sp1 site. Overexpression of the Sox5 protein activated the promoter activity. A 312-bp fragment surrounding the transcription...

Single-step generation of gene knockout-rescue system in pluripotent stem cells by promoter insertion with CRISPR/Cas9.

Science.gov (United States)

Matsunaga, Taichi; Yamashita, Jun K

2014-02-07

Specific gene knockout and rescue experiments are powerful tools in developmental and stem cell biology. Nevertheless, the experiments require multiple steps of molecular manipulation for gene knockout and subsequent rescue procedures. Here we report an efficient and single step strategy to generate gene knockout-rescue system in pluripotent stem cells by promoter insertion with CRISPR/Cas9 genome editing technology. We inserted a tetracycline-regulated inducible gene promoter (tet-OFF/TRE-CMV) upstream of the endogenous promoter region of vascular endothelial growth factor receptor 2 (VEGFR2/Flk1) gene, an essential gene for endothelial cell (EC) differentiation, in mouse embryonic stem cells (ESCs) with homologous recombination. Both homo- and hetero-inserted clones were efficiently obtained through a simple selection with a drug-resistant gene. The insertion of TRE-CMV promoter disrupted endogenous Flk1 expression, resulting in null mutation in homo-inserted clones. When the inserted TRE-CMV promoter was activated with doxycycline (Dox) depletion, Flk1 expression was sufficiently recovered from the downstream genomic Flk1 gene. Whereas EC differentiation was almost completely perturbed in homo-inserted clones, Flk1 rescue with TRE-CMV promoter activation restored EC appearance, indicating that phenotypic changes in EC differentiation can be successfully reproduced with this knockout-rescue system. Thus, this promoter insertion strategy with CRISPR/Cas9 would be a novel attractive method for knockout-rescue experiments. Copyright © 2014 Elsevier Inc. All rights reserved.

Approach of combined cancer gene therapy and radiation: response of promoters to ionizing radiation

International Nuclear Information System (INIS)

Anstett, A.

2005-09-01

Gene therapy is an emerging cancer treatment modality. We are interested in developing a radiation-inducible gene therapy system to sensitize the tumor vasculature to the effects of ionizing radiation (IR) treatment. An expression system based on irradiation-inducible promoters will drive the expression of anti-tumor genes in the tumor vasculature. Solid tumors are dependent on angio genesis, a process in which new blood vessels are formed from the pre-existing vasculature. Vascular endothelial cells are un transformed and genetically stable, thus avoiding the problem of resistance to the treatments. Vascular endothelial cells may therefore represent a suitable target for this therapeutic gene therapy strategy.The identification of IR-inducible promoters native to endothelial cells was performed by gene expression profiling using cDNA micro array technology. We describe the genes modified by clinically relevant doses of IR. The extension to high doses aimed at studying the effects of total radiation delivery to the tumor. The radio-inductiveness of the genes selected for promoter study was confirmed by RT-PCR. Analysis of the activity of promoters in response to IR was also assessed in a reporter plasmid. We found that authentic promoters cloned onto a plasmid are not suitable for cancer gene therapy due to their low induction after IR. In contrast, synthetic promoters containing repeated sequence-specific binding sites for IR-activated transcription factors such as NF-κB are potential candidates for gene therapy. The activity of five tandemly repeated TGGGGACTTTCCGC elements for NF-κB binding in a luciferase reporter was increased in a dose-dependent manner. Interestingly, the response to fractionated low doses was improved in comparison to the total single dose. Thus, we put present evidence that a synthetic promoter for NF-κB specific binding may have application in the radio-therapeutic treatment of cancer. (author)

Role of promoter element in c-mpl gene expression induced by TPO.

Science.gov (United States)

Sunohara, Masataka; Morikawa, Shigeru; Fuse, Akira; Sato, Iwao

2013-01-01

Thrombopoietin (TPO) and its receptor, c-Mpl, play the crucial role for the development of megakaryocyte and considered to regulate megakaryocytopoiesis. Previously we reported that TPO increased the c-mpl promoter activity determined by a transient expression system using a vector containing the luciferase gene as a reporter and the expression of the c-mpl gene is modulated by transcription through a protein kinase C (PKC)-dependent pathway in the megakaryoblastic cells. In this research, to elucidate the required elements in c-mpl promoter, the promoter activity of the deletion constructs and site-directed mutagenesis were measured by a transient transfection assay system. Destruction of -77GATA in c-mpl promoter decreased the activity by 22.8%. Our study elucidated that -77GATA involved in TPO-induced c-mpl gene expression in a human megakaryoblastic cell line, CMK.

[Divergence of paralogous growth-hormone-encoding genes and their promoters in Salmonidae].

Science.gov (United States)

Kamenskaya, D N; Pankova, M V; Atopkin, D M; Brykov, V A

2017-01-01

In many fish species, including salmonids, the growth-hormone is encoded by two duplicated paralogous genes, gh1 and gh2. Both genes were already in place at the time of divergence of species in this group. A comparison of the entire sequence of these genes of salmonids has shown that their conserved regions are associated with exons, while their most variable regions correspond to introns. Introns C and D include putative regulatory elements (sites Pit-1, CRE, and ERE), that are also conserved. In chars, the degree of polymorphism of gh2 gene is 2-3 times as large as that in gh1 gene. However, a comparison across all Salmonidae species would not extent this observation to other species. In both these chars' genes, the promoters are conserved mainly because they correspond to putative regulatory sequences (TATA box, binding sites for the pituitary transcription factor Pit-1 (F1-F4), CRE, GRE and RAR/RXR elements). The promoter of gh2 gene has a greater degree of polymorphism compared with gh1 gene promoter in all investigated species of salmonids. The observed differences in the rates of accumulation of changes in growth hormone encoding paralogs could be explained by differences in the intensity of selection.

Characterization of the distal promoter of the human pyruvate carboxylase gene in pancreatic beta cells.

Directory of Open Access Journals (Sweden)

Ansaya Thonpho

Full Text Available Pyruvate carboxylase (PC is an enzyme that plays a crucial role in many biosynthetic pathways in various tissues including glucose-stimulated insulin secretion. In the present study, we identify promoter usage of the human PC gene in pancreatic beta cells. The data show that in the human, two alternative promoters, proximal and distal, are responsible for the production of multiple mRNA isoforms as in the rat and mouse. RT-PCR analysis performed with cDNA prepared from human liver and islets showed that the distal promoter, but not the proximal promoter, of the human PC gene is active in pancreatic beta cells. A 1108 bp fragment of the human PC distal promoter was cloned and analyzed. It contains no TATA box but possesses two CCAAT boxes, and other putative transcription factor binding sites, similar to those of the distal promoter of rat PC gene. To localize the positive regulatory region in the human PC distal promoter, 5'-truncated and the 25-bp and 15-bp internal deletion mutants of the human PC distal promoter were generated and used in transient transfections in INS-1 832/13 insulinoma and HEK293T (kidney cell lines. The results indicated that positions -340 to -315 of the human PC distal promoter serve as (an activator element(s for cell-specific transcription factor, while the CCAAT box at -71/-67, a binding site for nuclear factor Y (NF-Y, as well as a GC box at -54/-39 of the human PC distal promoter act as activator sequences for basal transcription.

Genes that cooperate with tumor promoters in transformation

International Nuclear Information System (INIS)

Colburn, N.H.; Smith, B.M.

1988-01-01

Tumor-promoting phorbol esters, like growth factors, elicit pleiotropic responses involving biochemical pathways that lead to different biological responses. Genetic variant cell lines that are resistant to mitogenic, differentiation, or transformation responses to tumor promoters have been valuable tools for understanding the molecular bases of these responses. Studies using the mouse epidermal JB6 cell lines that are sensitive or resistant to tumor promoter-induced transformation have yielded new understanding of genetic and signal transduction events involved in neoplastic transformation. The isolation and characterization of cloned mouse promotion sensitivity genes pro-1 and pro-2 is reviewed. A new activity of pro-1 has been identified: when transfected into human cancer prone basal cell nevus syndrome fibroblasts but not normal fibroblasts mouse pro-1 confers lifespan extension of these cells. Recently, we have found tat a pro-1 homolog from a library of nasopharyngeal carcinoma, but not the homolog from a normal human library, is activated for transferring promotion sensitivity. The many genetic variants for responses to tumor promoters have also proved valuable for signal transduction studies. JPB P- cells fail to show the 12-O-tetradecanoyl-phorbol-13-acetate (TPA)-induced syntheses of two proteins of 15 and 16 kD seen in P+ cells. P-, P+, and TPA transformed cells show a progressive decrease in both basal and TPA-inducible levels of a protein kinase C substrate of 80 kD. P- cells are relatively resistant both to anchorage-independent transformation and to a protein band shift induced by the calcium analog lanthanum. It appears that one or more calcium-binding proteins and one or more pro genes may be critical determinants of tumor promoter-induced neoplastic transformation

Contribution of the Pmra Promoter to Expression of Genes in the Escherichia coli mra Cluster of Cell Envelope Biosynthesis and Cell Division Genes

Science.gov (United States)

Mengin-Lecreulx, Dominique; Ayala, Juan; Bouhss, Ahmed; van Heijenoort, Jean; Parquet, Claudine; Hara, Hiroshi

1998-01-01

Recently, a promoter for the essential gene ftsI, which encodes penicillin-binding protein 3 of Escherichia coli, was precisely localized 1.9 kb upstream from this gene, at the beginning of the mra cluster of cell division and cell envelope biosynthesis genes (H. Hara, S. Yasuda, K. Horiuchi, and J. T. Park, J. Bacteriol. 179:5802–5811, 1997). Disruption of this promoter (Pmra) on the chromosome and its replacement by the lac promoter (Pmra::Plac) led to isopropyl-β-d-thiogalactopyranoside (IPTG)-dependent cells that lysed in the absence of inducer, a defect which was complemented only when the whole region from Pmra to ftsW, the fifth gene downstream from ftsI, was provided in trans on a plasmid. In the present work, the levels of various proteins involved in peptidoglycan synthesis and cell division were precisely determined in cells in which Pmra::Plac promoter expression was repressed or fully induced. It was confirmed that the Pmra promoter is required for expression of the first nine genes of the mra cluster: mraZ (orfC), mraW (orfB), ftsL (mraR), ftsI, murE, murF, mraY, murD, and ftsW. Interestingly, three- to sixfold-decreased levels of MurG and MurC enzymes were observed in uninduced Pmra::Plac cells. This was correlated with an accumulation of the nucleotide precursors UDP–N-acetylglucosamine and UDP–N-acetylmuramic acid, substrates of these enzymes, and with a depletion of the pool of UDP–N-acetylmuramyl pentapeptide, resulting in decreased cell wall peptidoglycan synthesis. Moreover, the expression of ftsZ, the penultimate gene from this cluster, was significantly reduced when Pmra expression was repressed. It was concluded that the transcription of the genes located downstream from ftsW in the mra cluster, from murG to ftsZ, is also mainly (but not exclusively) dependent on the Pmra promoter. PMID:9721276

Absence of mutation at the 5'-upstream promoter region of the TPM4 gene from cardiac mutant axolotl (Ambystoma mexicanum).

Science.gov (United States)

Denz, Christopher R; Zhang, Chi; Jia, Pingping; Du, Jianfeng; Huang, Xupei; Dube, Syamalima; Thomas, Anish; Poiesz, Bernard J; Dube, Dipak K

2011-09-01

Tropomyosins are a family of actin-binding proteins that show cell-specific diversity by a combination of multiple genes and alternative RNA splicing. Of the 4 different tropomyosin genes, TPM4 plays a pivotal role in myofibrillogenesis as well as cardiac contractility in amphibians. In this study, we amplified and sequenced the upstream regulatory region of the TPM4 gene from both normal and mutant axolotl hearts. To identify the cis-elements that are essential for the expression of the TPM4, we created various deletion mutants of the TPM4 promoter DNA, inserted the deleted segments into PGL3 vector, and performed promoter-reporter assay using luciferase as the reporter gene. Comparison of sequences of the promoter region of the TPM4 gene from normal and mutant axolotl revealed no mutations in the promoter sequence of the mutant TPM4 gene. CArG box elements that are generally involved in controlling the expression of several other muscle-specific gene promoters were not found in the upstream regulatory region of the TPM4 gene. In deletion experiments, loss of activity of the reporter gene was noted upon deletion which was then restored upon further deletion suggesting the presence of both positive and negative cis-elements in the upstream regulatory region of the TPM4 gene. We believe that this is the first axolotl promoter that has ever been cloned and studied with clear evidence that it functions in mammalian cell lines. Although striated muscle-specific cis-acting elements are absent from the promoter region of TPM4 gene, our results suggest the presence of positive and negative cis-elements in the promoter region, which in conjunction with positive and negative trans-elements may be involved in regulating the expression of TPM4 gene in a tissue-specific manner.

Study on the binding sites of radiosensitivity associated transcription factor in the promoter region of Ier5 gene

International Nuclear Information System (INIS)

Cui Wei; Yin Lingling; Dong Lingyue

2012-01-01

Objective: To clarify the mechanism of immediate early response gene 5 (Ier5) transcription induced by radiation. Methods: Deletant construction, site-specific mutagenesis,electrophoretic mobility shift assay (EMSA) and chromatin immunoprecipitation (ChIP) were used to forecast the promoter region, binding sites and transcription factors of Ier5 gene in HeLa cells. Results: The promoter region of Ier5 gene might be in the region of Ier5 -8 deletant (-408 - -238 bp). The Ier5 gene had two transcription factors of GCF and NFI, and GCF had two binding sites located in the region of -388 - -382 bp and -274 - -270 bp of Ier5 promoter. The binding site of NFI was located in -362 - -357 bp of Ier5 promoter. GCF could inhibit the expression of Ier5 gene and this inhibition was diminished when the radiation dose increased. In contrast, NFI increased the expression of Ier5. Conclusions: The most possible region of Ier5 promoter is from -408 to -238 bp which has two binding sites for the radiosensitivity transcription factors of GCF and NFI that could negatively and positively regulate the expression of Ier5 respectively. (authors)

Aberrant gene promoter methylation associated with sporadic multiple colorectal cancer.

Directory of Open Access Journals (Sweden)

Victoria Gonzalo

difference in any evaluated gene. CONCLUSIONS: These results provide a proof-of-concept that gene promoter methylation is associated with tumor multiplicity. This underlying epigenetic defect may have noteworthy implications in the prevention of patients with sporadic CRC.

Transgelin gene is frequently downregulated by promoter DNA hypermethylation in breast cancer.

Science.gov (United States)

Sayar, Nilufer; Karahan, Gurbet; Konu, Ozlen; Bozkurt, Betul; Bozdogan, Onder; Yulug, Isik G

2015-01-01

CpG hypermethylation in gene promoters is a frequent mechanism of tumor suppressor gene silencing in various types of cancers. It usually occurs at early steps of cancer progression and can be detected easily, giving rise to development of promising biomarkers for both detection and progression of cancer, including breast cancer. 5-aza-2'-deoxycytidine (AZA) is a DNA demethylating and anti-cancer agent resulting in induction of genes suppressed via DNA hypermethylation. Using microarray expression profiling of AZA- or DMSO-treated breast cancer and non-tumorigenic breast (NTB) cells, we identified for the first time TAGLN gene as a target of DNA hypermethylation in breast cancer. TAGLN expression was significantly and frequently downregulated via promoter DNA hypermethylation in breast cancer cells compared to NTB cells, and also in 13/21 (61.9 %) of breast tumors compared to matched normal tissues. Analyses of public microarray methylation data showed that TAGLN was also hypermethylated in 63.02 % of tumors compared to normal tissues; relapse-free survival of patients was worse with higher TAGLN methylation; and methylation levels could discriminate between tumors and healthy tissues with 83.14 % sensitivity and 100 % specificity. Additionally, qRT-PCR and immunohistochemistry experiments showed that TAGLN expression was significantly downregulated in two more independent sets of breast tumors compared to normal tissues and was lower in tumors with poor prognosis. Colony formation was increased in TAGLN silenced NTB cells, while decreased in overexpressing BC cells. TAGLN gene is frequently downregulated by DNA hypermethylation, and TAGLN promoter methylation profiles could serve as a future diagnostic biomarker, with possible clinical impact regarding the prognosis in breast cancer.

Characteristics of lentiviral vectors harboring the proximal promoter of the vav proto-oncogene: a weak and efficient promoter for gene therapy.

Science.gov (United States)

Almarza, Elena; Río, Paula; Meza, Nestor W; Aldea, Montserrat; Agirre, Xabier; Guenechea, Guillermo; Segovia, José C; Bueren, Juan A

2007-08-01

Recent published data have shown the efficacy of gene therapy treatments of certain monogenic diseases. Risks of insertional oncogenesis, however, indicate the necessity of developing new vectors with weaker or cell-restricted promoters to minimize the trans-activation activity of integrated proviruses. We have inserted the proximal promoter of the vav proto-oncogene into self-inactivating lentiviral vectors (vav-LVs) and investigated the expression pattern and therapeutic efficacy of these vectors. Compared with other LVs frequently used in gene therapy, vav-LVs mediated a weak, though homogeneous and stable, expression in in vitro-cultured cells. Transplantation experiments using transduced mouse bone marrow and human CD34(+) cells confirmed the stable activity of the promoter in vivo. To investigate whether the weak activity of this promoter was compatible with a therapeutic effect, a LV expressing the Fanconi anemia A (FANCA) gene was constructed (vav-FANCA LV). Although this vector induced a low expression of FANCA, compared to the expression induced by a LV harboring the spleen focus-forming virus (SFFV) promoter, the two vectors corrected the phenotype of cells from a patient with FA-A with the same efficacy. We propose that self-inactivating vectors harboring weak promoters, such as the vav promoter, will improve the safety of gene therapy and will be of particular interest for the treatment of diseases where a high expression of the transgene is not required.

Identification and functional characterisation of the promoter of the calcium sensor gene CBL1 from the xerophyte Ammopiptanthus mongolicus

Directory of Open Access Journals (Sweden)

Yin Weilun

2010-01-01

Full Text Available Abstract Background CBL1 is a calcium sensor that regulates drought, cold and salt signals in Arabidopsis. Overexpression of CBL1 gene in Arabidopsis and in Ammopiptanthus mongolicus showed different tolerant activities. We are interested in understanding the molecular mechanism of the upstream region of the CBL1 gene of A. mongolicus (AmCBL1. We investigated and characterized the promoter of the AmCBL1 gene, for promoters play a very important role in regulating gene expression in eukaryotes. Results A 1683-bp 5' flanking region was isolated from A. mongolicus. The sequence was identified as AmCBL1 promoter. Analysis of the promoter sequence indicated a 690-bp intron and some basic cis-acting elements were related to various environmental stresses and plant hormones. To identify the functional region of the AmCBL1 promoter, five plant expression vectors fused with the GUS (β-glucuronidase gene, driven by series deleted fragments of AmCBL1 promoter at different lengths from -1659, -1414, -1048, -296 to -167 bp relative to the transcriptional start site were constructed and transformed into Nicotiana tabacum L. cv. 89. Functional properties of each promoter segment were examined by GUS staining and fluorescence quantitative analyses using at least three single-copy PCR-positive plants of transgenic tobacco, treated with various environmental stresses and plant hormones for different times. We demonstrated that the AmCBL1 promoter was a vascular-specific and multiple-stress-inducible promoter. Our results further imply that the promoter fragment B1S3 possessed sufficient essential cis-acting elements, accounting for vascular-specific and stress-induced expression patterns. It may also indicate that for response to some stresses certain cis-elements are required in tissues outside the region of the B1S3 construct. Conclusions To help resolve uncertainties about the upstream regulatory mechanism of the CBL1 gene in desert plants, we suggest that

[Inactivation of PMS2 gene by promoter methylation in nasopharyngeal carcinoma].

Science.gov (United States)

Ni, H F; Jiang, B; Zhou, Z; Li, Y; Yuan, X Y; Cao, X L; Huang, G W

2016-11-23

Objective: To investigate the inactivation of PMS2 gene mediated by promoter methylation and its regulatory mechanism in nasopharyngeal carcinoma (NPC). Methods: Fifty-four NPC tissues, 16 normal nasopharyngeal epithelia (NNE), 5 NPC cell lines (CNE1, CNE2, TWO3, HNE1 and HONE1) and 1 normal nasopharyngeal epithelial cell line (NP69) were collected.Methylation-specific PCR (MSP) was used to detect the PMS2 promoter methylation, semi-quantitative reverse transcription PCR (qRT-PCR) was applied to determine its mRNA expression, and immunohistochemistry (IHC) was used to detect the protein expression of PMS2. The expressions of PMS2 mRNA in CNE1 and CNE2 cells before and after treated with methyltransferase inhibitor 5-aza-2-deoxycytidine were analyzed by qRT-PCR. The impact of methylation and demethylation on the mRNA expression of PMS2, and the association of mRNA and protein expression of PMS2 with clinicopathological features of nasopharyngeal cancer were analyzed. Results: Methylation of PMS2 gene was detected in all of the five NPC cell lines, but not in normal nasopharyngeal epithelial NP69 cells. The methylation rate of PMS2 gene in NPC tissues was 63% (34/54), significantly higher than that of the normal nasopharyngeal epithelia (0/16, P PMS2 mRNA and protein were significantly down-regulated in the 54 NPC tissues when compared with those in the 16 NNE tissues ( P PMS2 mRNA was restored in the CNE1 and CNE2 cells.However, the expressions of PMS2 mRNA and protein were not significantly correlated with patients' age, gender, TNM stage, histopathologic type or lymph node metastasis ( P >0.05 for all). Conclusions: Promoter methylation-mediated inactivation of PMS2 gene participates in carcinogenesis and development of NPC. PMS2 may be a candidate tumor suppressor in the treatment for patients with inactivation of PMS2 promoter methylation.

A database of annotated promoters of genes associated with common respiratory and related diseases

KAUST Repository

Chowdhary, Rajesh

2012-07-01

Many genes have been implicated in the pathogenesis of common respiratory and related diseases (RRDs), yet the underlying mechanisms are largely unknown. Differential gene expression patterns in diseased and healthy individuals suggest that RRDs affect or are affected by modified transcription regulation programs. It is thus crucial to characterize implicated genes in terms of transcriptional regulation. For this purpose, we conducted a promoter analysis of genes associated with 11 common RRDs including allergic rhinitis, asthma, bronchiectasis, bronchiolitis, bronchitis, chronic obstructive pulmonary disease, cystic fibrosis, emphysema, eczema, psoriasis, and urticaria, many of which are thought to be genetically related. The objective of the present study was to obtain deeper insight into the transcriptional regulation of these disease-associated genes by annotating their promoter regions with transcription factors (TFs) and TF binding sites (TFBSs). We discovered many TFs that are significantly enriched in the target disease groups including associations that have been documented in the literature. We also identified a number of putative TFs/TFBSs that appear to be novel. The results of our analysis are provided in an online database that is freely accessible to researchers at http://www.respiratorygenomics.com. Promoter-associated TFBS information and related genomic features, such as histone modification sites, microsatellites, CpG islands, and SNPs, are graphically summarized in the database. Users can compare and contrast underlying mechanisms of specific RRDs relative to candidate genes, TFs, gene ontology terms, micro-RNAs, and biological pathways for the conduct of metaanalyses. This database represents a novel, useful resource for RRD researchers. Copyright © 2012 by the American Thoracic Society.

A database of annotated promoters of genes associated with common respiratory and related diseases

KAUST Repository

Chowdhary, Rajesh; Tan, Sinlam; Pavesi, Giulio; Jin, Gg; Dong, Difeng; Mathur, Sameer K.; Burkart, Arthur; Narang, Vipin; Glurich, Ingrid E.; Raby, Benjamin A.; Weiss, Scott T.; Limsoon, Wong; Liu, Jun; Bajic, Vladimir B.

2012-01-01

Many genes have been implicated in the pathogenesis of common respiratory and related diseases (RRDs), yet the underlying mechanisms are largely unknown. Differential gene expression patterns in diseased and healthy individuals suggest that RRDs affect or are affected by modified transcription regulation programs. It is thus crucial to characterize implicated genes in terms of transcriptional regulation. For this purpose, we conducted a promoter analysis of genes associated with 11 common RRDs including allergic rhinitis, asthma, bronchiectasis, bronchiolitis, bronchitis, chronic obstructive pulmonary disease, cystic fibrosis, emphysema, eczema, psoriasis, and urticaria, many of which are thought to be genetically related. The objective of the present study was to obtain deeper insight into the transcriptional regulation of these disease-associated genes by annotating their promoter regions with transcription factors (TFs) and TF binding sites (TFBSs). We discovered many TFs that are significantly enriched in the target disease groups including associations that have been documented in the literature. We also identified a number of putative TFs/TFBSs that appear to be novel. The results of our analysis are provided in an online database that is freely accessible to researchers at http://www.respiratorygenomics.com. Promoter-associated TFBS information and related genomic features, such as histone modification sites, microsatellites, CpG islands, and SNPs, are graphically summarized in the database. Users can compare and contrast underlying mechanisms of specific RRDs relative to candidate genes, TFs, gene ontology terms, micro-RNAs, and biological pathways for the conduct of metaanalyses. This database represents a novel, useful resource for RRD researchers. Copyright © 2012 by the American Thoracic Society.

Promoter analysis of the Chilo iridescent virus DNA polymerase and major capsid protein genes

International Nuclear Information System (INIS)

Nalcacioglu, Remziye; Marks, Hendrik; Vlak, Just M.; Demirbag, Zihni; Oers, Monique M. van

2003-01-01

The DNA polymerase (DNApol) and major capsid protein (MCP) genes were used as models to study promoter activity in Chilo iridescent virus (CIV). Infection of Bombyx mori SPC-BM-36 cells in the presence of inhibitors of DNA or protein synthesis showed that DNApol, as well as helicase, is an immediate-early gene and confirmed that the major capsid protein (MCP) is a late gene. Transcription of DNApol initiated 35 nt upstream and that of MCP 14 nt upstream of the translational start site. In a luciferase reporter gene assay both promoters were active only when cells were infected with CIV. For DNApol sequences between position -27 and -6, relative to the transcriptional start site, were essential for promoter activity. Furthermore, mutation of a G within the sequence TTGTTTT located just upstream of the DNApol transcription initiation site reduced the promoter activity by 25%. Sequences crucial for MCP promoter activity are located between positions -53 and -29

The role of ghrelin and ghrelin-receptor gene variants and promoter activity in type 2 diabetes.

Science.gov (United States)

Garcia, Edwin A; King, Peter; Sidhu, Kally; Ohgusu, Hideko; Walley, Andrew; Lecoeur, Cecile; Gueorguiev, Maria; Khalaf, Sahira; Davies, Derek; Grossman, Ashley B; Kojima, Masayasu; Petersenn, Stephan; Froguel, Phillipe; Korbonits, Márta

2009-08-01

Ghrelin and its receptor play an important role in glucose metabolism and energy homeostasis, and therefore they are functional candidates for genes carrying susceptibility alleles for type 2 diabetes. We assessed common genetic variation of the ghrelin (GHRL; five single nucleotide polymorphisms (SNP)) and the ghrelin-receptor (GHSR) genes (four SNPs) in 610 Caucasian patients with type 2 diabetes and 820 controls. In addition, promoter reporter assays were conducted to model the regulatory regions of both genes. Neither GHRL nor GHSR gene SNPs were associated with type 2 diabetes. One of the ghrelin haplotypes showed a marginal protective role in type 2 diabetes. We observed profound differences in the regulation of the GHRL gene according to promoter sequence variants. There are three different GHRL promoter haplotypes represented in the studied cohort causing up to 45% difference in the level of gene expression, while the promoter region of GHSR gene is primarily represented by a single haplotype. The GHRL and GHSR gene variants are not associated with type 2 diabetes, although GHRL promoter variants have significantly different activities.

Methylation of class II transactivator gene promoter IV is not associated with susceptibility to Multiple Sclerosis

Directory of Open Access Journals (Sweden)

Lincoln Matthew R

2008-07-01

Full Text Available Abstract Background Multiple sclerosis (MS is a complex trait in which alleles at or near the class II loci HLA-DRB1 and HLA-DQB1 contribute significantly to genetic risk. The MHC class II transactivator (MHC2TA is the master controller of expression of class II genes, and methylation of the promoter of this gene has been previously been shown to alter its function. In this study we sought to assess whether or not methylation of the MHC2TA promoter pIV could contribute to MS disease aetiology. Methods In DNA from peripheral blood mononuclear cells from a sample of 50 monozygotic disease discordant MS twins the MHC2TA promoter IV was sequenced and analysed by methylation specific PCR. Results No methylation or sequence variation of the MHC2TA promoter pIV was found. Conclusion The results of this study cannot support the notion that methylation of the pIV promoter of MHC2TA contributes to MS disease risk, although tissue and timing specific epigenetic modifications cannot be ruled out.

The progress of tumor gene-radiotherapy induced by Egr-1 promoter

International Nuclear Information System (INIS)

Guo Rui; Li Biao

2010-01-01

The promoter of early growth response gene-1 (Egr-1) is a cis-acting element of Egr-1, and its activity is regulated by inducers such as ionizing radiation, free radical. In designated gene-radiotherapy system, radiation combined with therapeutic gene (such as tumor necrosis factor-α gene, suicide gene) can spatially and temporally regulate therapeutic gene expression in the irradiated field, produced a marked effect, while little systemic toxicities were observed. The combination of radiotherapy and gene therapy is promising in tumor therapy. (authors)

Type 1 plaminogen activator inhibitor gene: Functional analysis and glucocorticoid regulation of its promoter

International Nuclear Information System (INIS)

Van Zonneveld, A.J.; Curriden, S.A.; Loskutoff, D.J.

1988-01-01

Plasminogen activator inhibitor type 1 is an important component of the fibrinolytic system and its biosynthesis is subject to complex regulation. To study this regulation at the level of transcription, the authors have identified and sequenced the promoter of the human plasminogen activator inhibitor type 1 gene. Nuclease protection experiments were performed by using endothelial cell mRNA and the transcription initiation (cap) site was established. Sequence analysis of the 5' flanking region of the gene revealed a perfect TATA box at position -28 to position -23, the conserved distance from the cap site. Comparative functional studies with the firefly luciferase gene as a reporter gene showed that fragments derived from this 5' flanking region exhibited high promoter activity when transfected into bovine aortic endothelial cells and mouse Ltk - fibroblasts but were inactive when introduced into HeLa cells. These studies indicate that the fragments contain the plasminogen activator inhibitor type 1 promoter and that it is expressed in a tissue-specific manner. Although the fragments were also silent in rat FTO2B hepatoma cells, their promoter activity could be induced up to 40-fold with the synthetic glucocorticoid dexamethasone. Promoter deletion mapping experiments and studies involving the fusion of promoter fragments to a heterologous gene indicated that dexamethasone induction is mediated by a glucocorticoid responsive element with enhancer-like properties located within the region between nucleotides -305 and +75 of the plasminogen activator inhibitor type 1 gene

Engineered promoters enable constant gene expression at any copy number in bacteria.

Science.gov (United States)

Segall-Shapiro, Thomas H; Sontag, Eduardo D; Voigt, Christopher A

2018-04-01

The internal environment of growing cells is variable and dynamic, making it difficult to introduce reliable parts, such as promoters, for genetic engineering. Here, we applied control-theoretic ideas to design promoters that maintained constant levels of expression at any copy number. Theory predicts that independence to copy number can be achieved by using an incoherent feedforward loop (iFFL) if the negative regulation is perfectly non-cooperative. We engineered iFFLs into Escherichia coli promoters using transcription-activator-like effectors (TALEs). These promoters had near-identical expression in different genome locations and plasmids, even when their copy number was perturbed by genomic mutations or changes in growth medium composition. We applied the stabilized promoters to show that a three-gene metabolic pathway to produce deoxychromoviridans could retain function without re-tuning when the stabilized-promoter-driven genes were moved from a plasmid into the genome.

Association of polymorphisms of interleukin-18 gene promoter region with polycystic ovary syndrome in chinese population

Directory of Open Access Journals (Sweden)

Li Mei-zhi

2010-10-01

Full Text Available Abstract Background Recent research shows that polycystic ovary syndrome (PCOS may have an association with low-grade chronic inflammation, and that PCOS may induce an increase in serum interleukin-18 (IL-18 levels. Methods To investigate the polymorphisms of the IL-18 gene promoters with PCOS, two single nucleotide polymorphisms (SNPs in the promoter of the IL-18 gene (at positions -607C/A and -137G/C in 118 Chinese women with PCOS and 79 controls were evaluated using polymerase chain reaction (PCR. Results No significant differences were found in the genotype distribution, allele frequency and haplotype frequency between the PCOS and control groups. Further analysis demonstrated a relationship between IL-18 gene promoter polymorphisms and PCOS insulin resistance (IR. Regarding the -137 allele frequency, G and C allele frequencies were 93.5% and 6.5%, respectively, in the PCOS with IR patients; G and C allele frequencies were 85.4% and 14.6%, respectively, in PCOS patients without IR (chi2 = 3.601, P = 0.048. Conclusions The presence of a polymorphism in the IL-18 gene was found to have no correlation with the occurrence of PCOS. Carriage of the C allele at position -137 in the promoter of the IL-18 gene may play a protective role from the development of PCOS IR.

The human oxytocin gene promoter is regulated by estrogens.

Science.gov (United States)

Richard, S; Zingg, H H

1990-04-15

Gonadal steroids affect brain function primarily by altering the expression of specific genes, yet the specific mechanisms by which neuronal target genes undergo such regulation are unknown. Recent evidence suggests that the expression of the neuropeptide gene for oxytocin (OT) is modulated by estrogens. We therefore examined the possibility that this regulation occurred via a direct interaction of the estrogen-receptor complex with cis-acting elements flanking the OT gene. DNA-mediated gene transfer experiments were performed using Neuro-2a neuroblastoma cells and chimeric plasmids containing portions of the human OT gene 5'-glanking region linked to the chloramphenicol acetyltransferase gene. We identified a 19-base pair region located at -164 to -146 upstream of the transcription start site which is capable of conferring estrogen responsiveness to the homologous as well as to a heterologous promoter. The hormonal response is strictly dependent on the presence of intracellular estrogen receptors, since estrogen induced stimulation occurred only in Neuro-2a cells co-transfected with an expression vector for the human estrogen receptor. The identified region contains a novel imperfect palindrome (GGTGACCTTGACC) with sequence similarity to other estrogen response elements (EREs). To define cis-acting elements that function in synergism with the ERE, sequences 3' to the ERE were deleted, including the CCAAT box, two additional motifs corresponding to the right half of the ERE palindrome (TGACC), as well as a CTGCTAA heptamer similar to the "elegans box" found in Caenorhabditis elegans. Interestingly, optimal function of the identified ERE was fully independent of these elements and only required a short promoter region (-49 to +36). Our studies define a molecular mechanism by which estrogens can directly modulate OT gene expression. However, only a subset of OT neurons are capable of binding estrogens, therefore, direct action of estrogens on the OT gene may be

Quantitative Analyses of Core Promoters Enable Precise Engineering of Regulated Gene Expression in Mammalian Cells

Science.gov (United States)

Ede, Christopher; Chen, Ximin; Lin, Meng-Yin; Chen, Yvonne Y.

2016-01-01

Inducible transcription systems play a crucial role in a wide array of synthetic biology circuits. However, the majority of inducible promoters are constructed from a limited set of tried-and-true promoter parts, which are susceptible to common shortcomings such as high basal expression levels (i.e., leakiness). To expand the toolbox for regulated mammalian gene expression and facilitate the construction of mammalian genetic circuits with precise functionality, we quantitatively characterized a panel of eight core promoters, including sequences with mammalian, viral, and synthetic origins. We demonstrate that this selection of core promoters can provide a wide range of basal gene expression levels and achieve a gradient of fold-inductions spanning two orders of magnitude. Furthermore, commonly used parts such as minimal CMV and minimal SV40 promoters were shown to achieve robust gene expression upon induction, but also suffer from high levels of leakiness. In contrast, a synthetic promoter, YB_TATA, was shown to combine low basal expression with high transcription rate in the induced state to achieve significantly higher fold-induction ratios compared to all other promoters tested. These behaviors remain consistent when the promoters are coupled to different genetic outputs and different response elements, as well as across different host-cell types and DNA copy numbers. We apply this quantitative understanding of core promoter properties to the successful engineering of human T cells that respond to antigen stimulation via chimeric antigen receptor signaling specifically under hypoxic environments. Results presented in this study can facilitate the design and calibration of future mammalian synthetic biology systems capable of precisely programmed functionality. PMID:26883397

ABERRANT METHYLATION OF THE PROMOTER OF APC, CDH13 AND MGMT GENES IN COLORECTAL CANCER PATIENTS

Directory of Open Access Journals (Sweden)

O. I. Kit

2016-01-01

Full Text Available Aberrant methylation of gene promoter regions is the main epigenetic change characterizing colorectal cancer. Methylation levels of 42 CpG-sites of promoter regions of the MGMT, APC and CDH13 genes in colorectal cancer were studied in comparison with methylation levels of the adjacent normal tissue in 25 patients. Pyrosequencing showed an increase in methylation levels of promoter regions of the MGMT, APC and CDH13 genes in tumor samples by 3 to 5 times. These tumor samples were screened for activating SNP-mutations in the KRAS (40 %, NRAS (0 % and BRAF (0 % oncogenes. SNP-mutations in the KRAS gene were accompanied by hypermethylation of one or more promoters of the studied genes. Association of this epigenetic index with tumor metastasis was proved. The data on an increase in methylation of the promoter regions of oncosupressor genes can be used as sensitive prognostic markers of progression and metastasis of colorectal cancer.

Gene Therapy for Human Lung Adenocarcinoma Using a Suicide Gene Driven by a Lung-Specific Promoter Delivered by JC Virus-Like Particles.

Directory of Open Access Journals (Sweden)

Chun-Nun Chao

Full Text Available Lung adenocarcinoma, the most commonly diagnosed type of lung cancer, has a poor prognosis even with combined surgery, chemotherapy, or molecular targeted therapies. Most patients are diagnosed with an in-operable advanced or metastatic disease, both pointing to the necessity of developing effective therapies for lung adenocarcinoma. Surfactant protein B (SP-B has been found to be overexpressed in lung adenocarcinoma. In addition, it has also been demonstrated that human lung adenocarcinoma cells are susceptible to the JC polyomavirus (JCPyV infection. Therefore, we designed that the JCPyV virus-like particle (VLP packaged with an SP-B promoter-driven thymidine kinase suicide gene (pSPB-tk for possible gene therapy of human lung adenocarcinoma. Plasmids expressing the GFP (pSPB-gfp or thymidine kinase gene (pSPB-tk under the control of the human SP-B promoter were constructed. The promoter's tissue specificity was tested by transfection of pSPB-gfp into A549, CH27, and H460 human lung carcinoma cells and non-lung cells. The JCPyV VLP's gene transfer efficiency and the selective cytotoxicity of pSPB-tk combined with ganciclovir (GCV were tested in vitro and in a xenograft mouse model. In the current study, we found that SP-B promoter-driven GFP was specifically expressed in human lung adenocarcinoma (A549 and large cell carcinoma (H460 cells. JCPyV VLPs were able to deliver a GFP reporter gene into A549 cells for expression. Selective cytotoxicity was observed in A549 but not non-lung cells that were transfected with pSPB-tk or infected with pSPB-tk-carrying JCPyV VLPs. In mice injected with pSPB-tk-carrying JCPyV VLPs through the tail vein and treated with ganciclovir (GCV, a potent 80% inhibition of growth of human lung adenocarcinoma nodules resulted. The JCPyV VLPs combined with the use of SP-B promoter demonstrates effectiveness as a potential gene therapy against human lung adenocarcinoma.

Gene Therapy for Human Lung Adenocarcinoma Using a Suicide Gene Driven by a Lung-Specific Promoter Delivered by JC Virus-Like Particles.

Science.gov (United States)

Chao, Chun-Nun; Lin, Mien-Chun; Fang, Chiung-Yao; Chen, Pei-Lain; Chang, Deching; Shen, Cheng-Huang; Wang, Meilin

2016-01-01

Lung adenocarcinoma, the most commonly diagnosed type of lung cancer, has a poor prognosis even with combined surgery, chemotherapy, or molecular targeted therapies. Most patients are diagnosed with an in-operable advanced or metastatic disease, both pointing to the necessity of developing effective therapies for lung adenocarcinoma. Surfactant protein B (SP-B) has been found to be overexpressed in lung adenocarcinoma. In addition, it has also been demonstrated that human lung adenocarcinoma cells are susceptible to the JC polyomavirus (JCPyV) infection. Therefore, we designed that the JCPyV virus-like particle (VLP) packaged with an SP-B promoter-driven thymidine kinase suicide gene (pSPB-tk) for possible gene therapy of human lung adenocarcinoma. Plasmids expressing the GFP (pSPB-gfp) or thymidine kinase gene (pSPB-tk) under the control of the human SP-B promoter were constructed. The promoter's tissue specificity was tested by transfection of pSPB-gfp into A549, CH27, and H460 human lung carcinoma cells and non-lung cells. The JCPyV VLP's gene transfer efficiency and the selective cytotoxicity of pSPB-tk combined with ganciclovir (GCV) were tested in vitro and in a xenograft mouse model. In the current study, we found that SP-B promoter-driven GFP was specifically expressed in human lung adenocarcinoma (A549) and large cell carcinoma (H460) cells. JCPyV VLPs were able to deliver a GFP reporter gene into A549 cells for expression. Selective cytotoxicity was observed in A549 but not non-lung cells that were transfected with pSPB-tk or infected with pSPB-tk-carrying JCPyV VLPs. In mice injected with pSPB-tk-carrying JCPyV VLPs through the tail vein and treated with ganciclovir (GCV), a potent 80% inhibition of growth of human lung adenocarcinoma nodules resulted. The JCPyV VLPs combined with the use of SP-B promoter demonstrates effectiveness as a potential gene therapy against human lung adenocarcinoma.

Identification of learning and memory genes in canine; promoter investigation and determining the selective pressure.

Science.gov (United States)

Seifi Moroudi, Reihane; Masoudi, Ali Akbar; Vaez Torshizi, Rasoul; Zandi, Mohammad

2014-12-01

One of the important behaviors of dogs is trainability which is affected by learning and memory genes. These kinds of the genes have not yet been identified in dogs. In the current research, these genes were found in animal models by mining the biological data and scientific literatures. The proteins of these genes were obtained from the UniProt database in dogs and humans. Not all homologous proteins perform similar functions, thus comparison of these proteins was studied in terms of protein families, domains, biological processes, molecular functions, and cellular location of metabolic pathways in Interpro, KEGG, Quick Go and Psort databases. The results showed that some of these proteins have the same performance in the rat or mouse, dog, and human. It is anticipated that the protein of these genes may be effective in learning and memory in dogs. Then, the expression pattern of the recognized genes was investigated in the dog hippocampus using the existing information in the GEO profile. The results showed that BDNF, TAC1 and CCK genes are expressed in the dog hippocampus, therefore, these genes could be strong candidates associated with learning and memory in dogs. Subsequently, due to the importance of the promoter regions in gene function, this region was investigated in the above genes. Analysis of the promoter indicated that the HNF-4 site of BDNF gene and the transcription start site of CCK gene is exposed to methylation. Phylogenetic analysis of protein sequences of these genes showed high similarity in each of these three genes among the studied species. The dN/dS ratio for BDNF, TAC1 and CCK genes indicates a purifying selection during the evolution of the genes.

Combination of Heavy-ion radiotherapy and p53-gene therapy by radio-sensitizing promoter for glioma

International Nuclear Information System (INIS)

Oga, Masaru; Koshikawa, Nobuko; Takenaga, Keizo; Iwadate, Yasuo; Nojima, Kumie

2005-01-01

In this study we have investigated the anti-tumor effect of the combination of heavy-ion radiotherapy, inducing p53-independent apoptosis, and p53-gene therapy, inducing p53-dependent apoptosis for glioma. To enhance the p53-dependent apoptosis, we chose the strategy to utilize the heavy-ion irradiation itself as a ''trigger'' by using radio-sensitizing promoter-E9ns-2/CMV chimeric promoter (Scott et al:2003) in p53-gene therapy. First, EGFP reporter gene with E9ns-2/CMV chimeric promoter was transfected in C6 rat glioma cell-line and the transfected-cell bulk was irradiated at dose of 3, 5, 10 Gy respectively with charged carbon particle (290 MeV/nucleon). The light upregulation of EGFP was observed in 24 hours after 5 Gy irradiation. On the basis of this result, p53 gene with E9ns-2/CMV chimeric promoter was transfected in p53-mutant U373MG human glioma cell-line and the transfected-cell bulk was irradiated at dose of 5 Gy. There was, however, no obvious p53-upregulation at any time-point, so far. Further investigation is needed to clarify the appropriate experimental system. (author)

PlantPAN: Plant promoter analysis navigator, for identifying combinatorial cis-regulatory elements with distance constraint in plant gene groups

Directory of Open Access Journals (Sweden)

Huang Hsien-Da

2008-11-01

Full Text Available Abstract Background The elucidation of transcriptional regulation in plant genes is important area of research for plant scientists, following the mapping of various plant genomes, such as A. thaliana, O. sativa and Z. mays. A variety of bioinformatic servers or databases of plant promoters have been established, although most have been focused only on annotating transcription factor binding sites in a single gene and have neglected some important regulatory elements (tandem repeats and CpG/CpNpG islands in promoter regions. Additionally, the combinatorial interaction of transcription factors (TFs is important in regulating the gene group that is associated with the same expression pattern. Therefore, a tool for detecting the co-regulation of transcription factors in a group of gene promoters is required. Results This study develops a database-assisted system, PlantPAN (Plant Promoter Analysis Navigator, for recognizing combinatorial cis-regulatory elements with a distance constraint in sets of plant genes. The system collects the plant transcription factor binding profiles from PLACE, TRANSFAC (public release 7.0, AGRIS, and JASPER databases and allows users to input a group of gene IDs or promoter sequences, enabling the co-occurrence of combinatorial transcription factor binding sites (TFBSs within a defined distance (20 bp to 200 bp to be identified. Furthermore, the new resource enables other regulatory features in a plant promoter, such as CpG/CpNpG islands and tandem repeats, to be displayed. The regulatory elements in the conserved regions of the promoters across homologous genes are detected and presented. Conclusion In addition to providing a user-friendly input/output interface, PlantPAN has numerous advantages in the analysis of a plant promoter. Several case studies have established the effectiveness of PlantPAN. This novel analytical resource is now freely available at http://PlantPAN.mbc.nctu.edu.tw.

Characterization of the human UDP-galactose:ceramide galactosyltransferase gene promoter.

Science.gov (United States)

Tencomnao, T; Yu, R K; Kapitonov, D

2001-02-16

UDP-galactose:ceramide galactosyltransferase (CGT, EC 2.4.1.45) is a key enzyme in the biosynthesis of galactocerebroside, the most abundant glycosphingolipid in the myelin sheath. An 8 kb fragment upstream from the transcription initiation site of CGT gene was isolated from a human genomic DNA library. Primer extension analysis revealed a single transcription initiation site 329 bp upstream from the ATG start codon. Neither a consensus TATA nor a CCAAT box was identified in the proximity to the transcription start site; however, this region contains a high GC content and multiple putative regulatory elements. To investigate the transcriptional regulation of CGT, a series of 5' deletion constructs of the 5'-flanking region were generated and cloned upstream from the luciferase reporter gene. By comparing promoter activity in the human oligodendroglioma (HOG) and human neuroblastoma (LAN-5) cell lines, we found that the CGT promoter functions in a cell type-specific manner. Three positive cis-acting regulatory regions were identified, including a proximal region at -292/-256 which contains the potential binding sites for known transcription factors (TFs) such as Ets and SP1 (GC box), a distal region at -747/-688 comprising a number of binding sites such as the ERE half-site, NF1-like, TGGCA-BP, and CRE, and a third positive cis-acting region distally localized at -1325/-1083 consisting of binding sites for TFs such as nitrogen regulatory, TCF-1, TGGCA-BP, NF-IL6, CF1, bHLH, NF1-like, GATA, and gamma-IRE. A negative cis-acting domain localized in a far distal region at -1594/-1326 was also identified. Our results suggest the presence of both positive and negative cis-regulatory regions essential for the cell-specific expression in the TATA-less promoter of the human CGT gene.

Identification, isolation and evaluation of a constitutive sucrose phosphate synthase gene promoter from tomato

International Nuclear Information System (INIS)

Naqvi, R.Z.; Mubeen, H.; Maqsood, A.; Khatoon, A.

2017-01-01

Sucrose phosphate synthase (SPS) is one of the abundantly expressed genes in plants. The promoters of SPS gene was identified, analyzed and retrieved from high throughput genomic sequence (HTGS) database. The cis-acting regulatory elements and transcription start sites of promoter were identified through different bioinformatics tools. The SPS promoter was isolated from Solanum lycopersicum and was initially cloned in TA vector (pTZ57R/T). Later on this promoter was transferred to a plant expression binary vector, pGR1 (pGRSPS) that was used for the transient GUS expression studies in various tissues of Nicotiana tabacum. SPS promoter was also cloned in plant stable expression vector pGA482 (pGASPS) and was transformed in Nicotiana tabacum through Agrobacterium-mediated transformation method. The histochemical GUS expression analysis of both transient and stable transgenic plants for this promoter indicated its functional importance in regulating gene expression in a constitutive manner. It was concluded that SPS promoter is constitutively expressed with a strength equivalent to CaMV 2X35S promoter. The promoter isolated through these studies may be effectively substituted in plant genetic engineering with other constitutive promoter for transgene expression in economically important agricultural crops. (author)

Two distinct promoters drive transcription of the human D1A dopamine receptor gene.

Science.gov (United States)

Lee, S H; Minowa, M T; Mouradian, M M

1996-10-11

The human D1A dopamine receptor gene has a GC-rich, TATA-less promoter located upstream of a small, noncoding exon 1, which is separated from the coding exon 2 by a 116-base pair (bp)-long intron. Serial 3'-deletions of the 5'-noncoding region of this gene, including the intron and 5'-end of exon 2, resulted in 80 and 40% decrease in transcriptional activity of the upstream promoter in two D1A-expressing neuroblastoma cell lines, SK-N-MC and NS20Y, respectively. To investigate the function of this region, the intron and 245 bp at the 5'-end of exon 2 were investigated. Transient expression analyses using various chloramphenicol acetyltransferase constructs showed that the transcriptional activity of the intron is higher than that of the upstream promoter by 12-fold in SK-N-MC cells and by 5.5-fold in NS20Y cells in an orientation-dependent manner, indicating that the D1A intron is a strong promoter. Primer extension and ribonuclease protection assays revealed that transcription driven by the intron promoter is initiated at the junction of intron and exon 2 and at a cluster of nucleotides located 50 bp downstream from this junction. The same transcription start sites are utilized by the chloramphenicol acetyltransferase constructs employed in transfections as well as by the D1A gene expressed within the human caudate. The relative abundance of D1A transcripts originating from the upstream promoter compared with those transcribed from the intron promoter is 1.5-2.9 times in SK-N-MC cells and 2 times in the human caudate. Transcript stability studies in SK-N-MC cells revealed that longer D1A mRNA molecules containing exon 1 are degraded 1.8 times faster than shorter transcripts lacking exon 1. Although gel mobility shift assay could not detect DNA-protein interaction at the D1A intron, competitive co-transfection using the intron as competitor confirmed the presence of trans-acting factors at the intron. These data taken together indicate that the human D1A gene has

Light-regulated promoters for tunable, temporal, and affordable control of fungal gene expression.

Science.gov (United States)

Fuller, Kevin K; Dunlap, Jay C; Loros, Jennifer J

2018-05-01

Regulatable promoters are important genetic tools, particularly for assigning function to essential and redundant genes. They can also be used to control the expression of enzymes that influence metabolic flux or protein secretion, thereby optimizing product yield in bioindustry. This review will focus on regulatable systems for use in filamentous fungi, an important group of organisms whose members include key research models, devastating pathogens of plants and animals, and exploitable cell factories. Though we will begin by cataloging those promoters that are controlled by nutritional or chemical means, our primary focus will rest on those who can be controlled by a literal flip-of-the-switch: promoters of light-regulated genes. The vvd promoter of Neurospora will first serve as a paradigm for how light-driven systems can provide tight, robust, tunable, and temporal control of either autologous or heterologous fungal proteins. We will then discuss a theoretical approach to, and practical considerations for, the development of such promoters in other species. To this end, we have compiled genes from six previously published light-regulated transcriptomic studies to guide the search for suitable photoregulatable promoters in your fungus of interest.

Four inducible promoters for controlled gene expression in the oleaginous yeast Rhodotorula toruloides

Directory of Open Access Journals (Sweden)

Alexander Michael Bedford Johns

2016-10-01

Full Text Available Rhodotorula (Rhodosporidium toruloides is an oleaginous yeast with great biotechnological potential, capable of accumulating lipid up to 70 % of its dry biomass, and of carotenoid biosynthesis. However, few molecular genetic tools are available for manipulation of this basidiomycete yeast and its high genomic GC content can make routine cloning difficult. We have developed plasmid vectors for transformation of R. toruloides which include elements for Saccharomyces cerevisiae in-yeast assembly; this method is robust to the assembly of GC-rich DNA and of large plasmids. Using such vectors we screened for controllable promoters, and identified inducible promoters from the genes NAR1, ICL1, CTR3 and MET16. These four promoters have independent induction/repression conditions and exhibit different levels and rates of induction in R. toruloides, making them appropriate for controllable transgene expression in different experimental situations. Nested deletions were used to identify regulatory regions in the four promoters, and to delimit the minimal inducible promoters, which are as small as 200 bp for the NAR1 promoter. The NAR1 promoter shows very tight regulation under repressed conditions as determined both by an EGFP reporter gene and by conditional rescue of a leu2 mutant. These new tools facilitate molecular genetic manipulation and controllable gene expression in R. toruloides.

Cloning and characterization of the human integrin β6 gene promoter.

Directory of Open Access Journals (Sweden)

Mingyan Xu

Full Text Available The integrin β6 (ITGB6 gene, which encodes the limiting subunit of the integrin αvβ6 heterodimer, plays an important role in wound healing and carcinogenesis. The mechanism underlying ITGB6 regulation, including the identification of DNA elements and cognate transcription factors responsible for basic transcription of human ITGB6 gene, remains unknown. This report describes the cloning and characterization of the human ITGB6 promoter. Using 5'-RACE (rapid amplification of cDNA ends analysis, the transcriptional initiation site was identified. Promoter deletion analysis identified and functionally validated a TATA box located in the region -24 to -18 base pairs upstream of the ITGB6 promoter. The regulatory elements for transcription of the ITGB6 gene were predominantly located -289 to -150 from the ITGB6 promoter and contained putative binding sites for transcription factors such as STAT3 and C/EBPα. Using chromatin immunoprecipitation assays, this study has demonstrated, for the first time, that transcription factors STAT3 and C/EBPα are involved in the positive regulation of ITGB6 transcription in oral squamous cell carcinoma cells. These findings have important implications for unraveling the mechanism of abnormal ITGB6 activation in tissue remodeling and tumorigenesis.

Quantitative promoter methylation analysis of multiple cancer-related genes in renal cell tumors

Directory of Open Access Journals (Sweden)

Oliveira Jorge

2007-07-01

Full Text Available Abstract Background Aberrant promoter hypermethylation of cancer-associated genes occurs frequently during carcinogenesis and may serve as a cancer biomarker. In this study we aimed at defining a quantitative gene promoter methylation panel that might identify the most prevalent types of renal cell tumors. Methods A panel of 18 gene promoters was assessed by quantitative methylation-specific PCR (QMSP in 85 primarily resected renal tumors representing the four major histologic subtypes (52 clear cell (ccRCC, 13 papillary (pRCC, 10 chromophobe (chRCC, and 10 oncocytomas and 62 paired normal tissue samples. After genomic DNA isolation and sodium bisulfite modification, methylation levels were determined and correlated with standard clinicopathological parameters. Results Significant differences in methylation levels among the four subtypes of renal tumors were found for CDH1 (p = 0.0007, PTGS2 (p = 0.002, and RASSF1A (p = 0.0001. CDH1 hypermethylation levels were significantly higher in ccRCC compared to chRCC and oncocytoma (p = 0.00016 and p = 0.0034, respectively, whereas PTGS2 methylation levels were significantly higher in ccRCC compared to pRCC (p = 0.004. RASSF1A methylation levels were significantly higher in pRCC than in normal tissue (p = 0.035. In pRCC, CDH1 and RASSF1A methylation levels were inversely correlated with tumor stage (p = 0.031 and nuclear grade (p = 0.022, respectively. Conclusion The major subtypes of renal epithelial neoplasms display differential aberrant CDH1, PTGS2, and RASSF1A promoter methylation levels. This gene panel might contribute to a more accurate discrimination among common renal tumors, improving preoperative assessment and therapeutic decision-making in patients harboring suspicious renal masses.

Natural selection in a population of Drosophila melanogaster explained by changes in gene expression caused by sequence variation in core promoter regions.

Science.gov (United States)

Sato, Mitsuhiko P; Makino, Takashi; Kawata, Masakado

2016-02-09

Understanding the evolutionary forces that influence variation in gene regulatory regions in natural populations is an important challenge for evolutionary biology because natural selection for such variations could promote adaptive phenotypic evolution. Recently, whole-genome sequence analyses have identified regulatory regions subject to natural selection. However, these studies could not identify the relationship between sequence variation in the detected regions and change in gene expression levels. We analyzed sequence variations in core promoter regions, which are critical regions for gene regulation in higher eukaryotes, in a natural population of Drosophila melanogaster, and identified core promoter sequence variations associated with differences in gene expression levels subjected to natural selection. Among the core promoter regions whose sequence variation could change transcription factor binding sites and explain differences in expression levels, three core promoter regions were detected as candidates associated with purifying selection or selective sweep and seven as candidates associated with balancing selection, excluding the possibility of linkage between these regions and core promoter regions. CHKov1, which confers resistance to the sigma virus and related insecticides, was identified as core promoter regions that has been subject to selective sweep, although it could not be denied that selection for variation in core promoter regions was due to linked single nucleotide polymorphisms in the regulatory region outside core promoter regions. Nucleotide changes in core promoter regions of CHKov1 caused the loss of two basal transcription factor binding sites and acquisition of one transcription factor binding site, resulting in decreased gene expression levels. Of nine core promoter regions regions associated with balancing selection, brat, and CG9044 are associated with neuromuscular junction development, and Nmda1 are associated with learning

A preliminary study of the relationship between promoter methylation of the ABCG1, GALNT2 and HMGCR genes and coronary heart disease.

Directory of Open Access Journals (Sweden)

Ping Peng

Full Text Available To investigate the association of ABCG1, GALNT2 and HMGCR genes promoter DNA methylation with coronary heart disease (CHD and explore the interaction between their methylation status and the CHD patients' clinical characteristics in Han Chinese population.Methylation-specific polymerase chain reaction (MSP technology was used to examine the role of the aberrant gene promoter methylation in CHD in Han Chinese population. A total of 85 CHD patients and 54 participants without CHD confirmed by angiography were recruited. 82.8% of the participants with ABCG1 gene promoter hypermethylation have CHD, while only 17.4% of the participants without hypermethylation have it. The average age of the participants with GALNT2 gene promoter hypermethylation is 62.10 ± 8.21, while that of the participants without hypermethylation is 57.28 ± 9.87; in the former group, 75.4% of the participants have CHD, compared to only 50% in the latter group. As for the HMGCR gene, the average age of the participants with promoter hypermethylation is 63.24 ± 8.10 and that of the participants without hypermethylation is 57.79 ± 9.55; its promoter hypermethylation is likely to be related to smoking. Our results indicated a significant statistical association of promoter methylation of the ABCG1 gene with increased risk of CHD (OR = 19.966; 95% CI, 7.319-54.468; P*<0.001; P*: adjusted for age, gender, smoking, lipid level, hypertension, and diabetes. Similar results were obtained for that of the GALNT2 gene (OR = 2.978; 95% CI, 1.335-6.646; P* = 0.008, but not of HMGCR gene (OR = 1.388; 95% CI, 0.572-3.371; P*  = 0.469.The present work provides evidence to support the association of promoter DNA methylation status with the risk profile of CHD. Our data indicates that promoter DNA hypermethylation of the ABCG1 and GALNT2 genes, but not the HMGCR gene, is associated with an increased risk of CHD. CHD, smoking and aging are likely to be the important factors influencing DNA

Monoamine oxidase A gene promoter methylation and transcriptional downregulation in an offender population with antisocial personality disorder.

Science.gov (United States)

Checknita, D; Maussion, G; Labonté, B; Comai, S; Tremblay, R E; Vitaro, F; Turecki, N; Bertazzo, A; Gobbi, G; Côté, G; Turecki, G

2015-03-01

Antisocial personality disorder (ASPD) is characterised by elevated impulsive aggression and increased risk for criminal behaviour and incarceration. Deficient activity of the monoamine oxidase A (MAOA) gene is suggested to contribute to serotonergic system dysregulation strongly associated with impulsive aggression and antisocial criminality. To elucidate the role of epigenetic processes in altered MAOA expression and serotonin regulation in a population of incarcerated offenders with ASPD compared with a healthy non-incarcerated control population. Participants were 86 incarcerated participants with ASPD and 73 healthy controls. MAOA promoter methylation was compared between case and control groups. We explored the functional impact of MAOA promoter methylation on gene expression in vitro and blood 5-HT levels in a subset of the case group. Results suggest that MAOA promoter hypermethylation is associated with ASPD and may contribute to downregulation of MAOA gene expression, as indicated by functional assays in vitro, and regression analysis with whole-blood serotonin levels in offenders with ASPD. These results are consistent with prior literature suggesting MAOA and serotonergic dysregulation in antisocial populations. Our results offer the first evidence suggesting epigenetic mechanisms may contribute to MAOA dysregulation in antisocial offenders. Royal College of Psychiatrists.

The promoter of the pepper pathogen-induced membrane protein gene CaPIMP1 mediates environmental stress responses in plants.

Science.gov (United States)

Hong, Jeum Kyu; Hwang, Byung Kook

2009-01-01

The promoter of the pepper pathogen-induced membrane protein gene CaPIMP1 was analyzed by an Agrobacterium-mediated transient expression assay in tobacco leaves. Several stress-related cis-acting elements (GT-1, W-box and ABRE) are located within the CaPIMP1 promoter. In tobacco leaf tissues transiently transformed with a CaPIMP1 promoter-beta-glucuronidase (GUS) gene fusion, serially 5'-deleted CaPIMP1 promoters were differentially activated by Pseudomonas syringae pv. tabaci, ethylene, methyl jasmonate, abscisic acid, and nitric oxide. The -1,193 bp region of the CaPIMP1 gene promoter sequence exhibited full promoter activity. The -417- and -593 bp promoter regions were sufficient for GUS gene activation by ethylene and methyl jasmonate treatments, respectively. However, CaPIMP1 promoter sequences longer than -793 bp were required for promoter activation by abscisic acid and sodium nitroprusside treatments. CaPIMP1 expression was activated in pepper leaves by treatment with ethylene, methyl jasmonate, abscisic acid, beta-amino-n-butyric acid, NaCl, mechanical wounding, and low temperature, but not with salicylic acid. Overexpression of CaPIMP1 in Arabidopsis conferred hypersensitivity to mannitol, NaCl, and ABA during seed germination but not during seedling development. In contrast, transgenic plants overexpressing CaPIMP1 exhibited enhanced tolerance to oxidative stress induced by methyl viologen during germination and early seedling stages. These results suggest that CaPIMP1 expression may alter responsiveness to environmental stress, as well as to pathogen infection.

Identification of the MUC2 Promoter as a Strong Promoter for Intestinal Gene Expression through Generation of Transgenic Quail Expressing GFP in Gut Epithelial Cells

Directory of Open Access Journals (Sweden)

Rachel M. Woodfint

2017-01-01

Full Text Available Identification of tissue- and stage-specific gene promoters is valuable for delineating the functional roles of specific genes in genetically engineered animals. Here, through the comparison of gene expression in different tissues by analysis of a microarray database, the intestinal specificity of mucin 2 (MUC2 expression was identified in mice and humans, and further confirmed in chickens by RT-PCR (reverse transcription-PCR analysis. An analysis of cis-acting elements in avian MUC2 gene promoters revealed conservation of binding sites, within a 2.9 kb proximal promoter region, for transcription factors such as caudal type homeobox 2 (CDX2, GATA binding protein 4 (GATA4, hepatocyte nuclear factor 4 α (HNF4A, and transcription factor 4 (TCF4 that are important for maintaining intestinal homeostasis and functional integrity. By generating transgenic quail, we demonstrated that the 2.9 kb chicken MUC2 promoter could drive green fluorescent protein (GFP reporter expression exclusively in the small intestine, large intestine, and ceca. Fluorescence image analysis further revealed GFP expression in intestine epithelial cells. The GFP expression was barely detectable in the embryonic intestine, but increased during post-hatch development. The spatiotemporal expression pattern of the reporter gene confirmed that the 2.9 kb MUC2 promoter could retain the regulatory element to drive expression of target genes in intestinal tissues after hatching. This new transgene expression system, using the MUC2 promoter, will provide a new method of overexpressing target genes to study gene function in the avian intestine.

Differential effects of simple repeating DNA sequences on gene expression from the SV40 early promoter.

Science.gov (United States)

Amirhaeri, S; Wohlrab, F; Wells, R D

1995-02-17

The influence of simple repeat sequences, cloned into different positions relative to the SV40 early promoter/enhancer, on the transient expression of the chloramphenicol acetyltransferase (CAT) gene was investigated. Insertion of (G)29.(C)29 in either orientation into the 5'-untranslated region of the CAT gene reduced expression in CV-1 cells 50-100 fold when compared with controls with random sequence inserts. Analysis of CAT-specific mRNA levels demonstrated that the effect was due to a reduction of CAT mRNA production rather than to posttranscriptional events. In contrast, insertion of the same insert in either orientation upstream of the promoter-enhancer or downstream of the gene stimulated gene expression 2-3-fold. These effects could be reversed by cotransfection of a competitor plasmid carrying (G)25.(C)25 sequences. The results suggest that a G.C-binding transcription factor modulates gene expression in this system and that promoter strength can be regulated by providing protein-binding sites in trans. Although constructs containing longer tracts of alternating (C-G), (T-G), or (A-T) sequences inhibited CAT expression when inserted in the 5'-untranslated region of the CAT gene, the amount of CAT mRNA was unaffected. Hence, these inhibitions must be due to posttranscriptional events, presumably at the level of translation. These effects of microsatellite sequences on gene expression are discussed with respect to recent data on related simple repeat sequences which cause several human genetic diseases.

Combination of heavy-ion radiotherapy and p53-gene therapy by radio- and hypoxia-sensitizing promoter for glioma

International Nuclear Information System (INIS)

Oga, Masaru; Koshikawa, Nobuko; Takenaga, Keizo; Iwadate, Yasuo; Nojima, Kumie

2006-01-01

In this study we have started to investigate the anti-tumor effect of the combination of heavy-ion radiotherapy, inducing p53-independent apoptosis, and p53-gene therapy, inducing p53-dependent apoptosis for glioma. To enhance the p53-dependent apoptosis, we chose the strategy to utilize the heavy-ion irradiation itself as a ''trigger'' by using radio-sensitizing E 9ns-2 /cytomegalovirus (CMV) chimeric promoter (Scott et al: 2003) in p53-gene therapy. Our study in the first year, however, suggested the uselessness of E 9ns-2 /CMV chimeric promoter. Then we applied E 9ns-2 /Epo5/CMV-radio and hypoxia-sensitizing chimeric promoter to amplify p53 gene exopression. P53 gene with E 9ns2 /Epo5/CMV chimeric promoter was transfected in p53-mutant U373MG human glioma cell-line and the transfected-cell bulk was irradiated at dose of 1 Gy of high linear energy transfer (LET)-carbon ion beam or low-LET X-ray under various hypoxic conditions. The result suggested the possible role of 1 Gy of high LET-carbon ion beam as a ''useful trigger'' to enhance a selective anti-tumor effect toward glioma under hypoxic condition through amplification of p53 gene expression. (author)

Functional dissection of a napin gene promoter: identification of promoter elements required for embryo and endosperm-specific transcription.

Science.gov (United States)

Ellerström, M; Stålberg, K; Ezcurra, I; Rask, L

1996-12-01

The promoter region (-309 to +44) of the Brassica napus storage protein gene napA was studied in transgenic tobacco by successive 5' as well as internal deletions fused to the reporter gene GUS (beta-glucuronidase). The expression in the two main tissues of the seed, the endosperm and the embryo, was shown to be differentially regulated. This tissue-specific regulation within the seed was found to affect the developmental expression during seed development. The region between -309 to -152, which has a large effect on quantitative expression, was shown to harbour four elements regulating embryo and one regulating endosperm expression. This region also displayed enhancer activity. Deletion of eight bp from position -152 to position -144 totally abolished the activity of the napA promoter. This deletion disrupted a cis element with similarity to an ABA-responsive element (ABRE) overlapping with an E-box, demonstrating its crucial importance for quantitative expression. An internal deletion of the region -133 to -120, resulted in increased activity in both leaves and endosperm and a decreased activity in the embryo. Within this region, a cis element similar to the (CA)n element, found in other storage protein promoters, was identified. This suggest that the (CA)n element is important for conferring seed specificity by serving both as an activator and a repressor element.

Identification of distal silencing elements in the murine interferon-A11 gene promoter.

Science.gov (United States)

Roffet, P; Lopez, S; Navarro, S; Bandu, M T; Coulombel, C; Vignal, M; Doly, J; Vodjdani, G

1996-08-01

The murine interferon-A11 (Mu IFN-A11) gene is a member of the IFN-A multigenic family. In mouse L929 cells, the weak response of the gene's promoter to viral induction is due to a combination of both a point mutation in the virus responsive element (VRE) and the presence of negatively regulating sequences surrounding the VRE. In the distal part of the promoter, the negatively acting E1E2 sequence was delimited. This sequence displays an inhibitory effect in either orientation or position on the inducibility of a virus-responsive heterologous promoter. It selectively represses VRE-dependent transcription but is not able to reduce the transcriptional activity of a VRE-lacking promoter. In a transient transfection assay, an E1E2-containing DNA competitor was able to derepress the native Mu IFN-A11 promoter. Specific nuclear factors bind to this sequence; thus the binding of trans-regulators participates in the repression of the Mu IFN-A11 gene. The E1E2 sequence contains an IFN regulatory factor (IRF)-binding site. Recombinant IRF2 binds this sequence and anti-IRF2 antibodies supershift a major complex formed with nuclear extracts. The protein composing the complex is 50 kDa in size, indicating the presence of IRF2 or antigenically related proteins in the complex. The Mu IFN-A11 gene is the first example within the murine IFN-A family, in which a distal promoter element has been identified that can negatively modulate the transcriptional response to viral induction.

Isolation and characterization of an ubiquitin extension protein gene (JcUEP) promoter from Jatropha curcas.

Science.gov (United States)

Tao, Yan-Bin; He, Liang-Liang; Niu, Long-Jian; Xu, Zeng-Fu

2015-04-01

The JcUEP promoter is active constitutively in the bio-fuel plant Jatropha curcas , and is an alternative to the widely used CaMV35S promoter for driving constitutive overexpression of transgenes in Jatropha. Well-characterized promoters are required for transgenic breeding of Jatropha curcas, a biofuel feedstock with great potential for production of bio-diesel and bio-jet fuel. In this study, an ubiquitin extension protein gene from Jatropha, designated JcUEP, was identified to be ubiquitously expressed. Thus, we isolated a 1.2 kb fragment of the 5' flanking region of JcUEP and evaluated its activity as a constitutive promoter in Arabidopsis and Jatropha using the β-glucuronidase (GUS) reporter gene. As expected, histochemical GUS assay showed that the JcUEP promoter was active in all Arabidopsis and Jatropha tissues tested. We also compared the activity of the JcUEP promoter with that of the cauliflower mosaic virus 35S (CaMV35S) promoter, a well-characterized constitutive promoter conferring strong transgene expression in dicot species, in various tissues of Jatropha. In a fluorometric GUS assay, the two promoters showed similar activities in stems, mature leaves and female flowers; while the CaMV35S promoter was more effective than the JcUEP promoter in other tissues, especially young leaves and inflorescences. In addition, the JcUEP promoter retained its activity under stress conditions in low temperature, high salt, dehydration and exogenous ABA treatments. These results suggest that the plant-derived JcUEP promoter could be an alternative to the CaMV35S promoter for driving constitutive overexpression of transgenes in Jatropha and other plants.

Effect of external and internal factors on the expression of reporter genes driven by the N resistance gene promoter.

Science.gov (United States)

Kathiria, Palak; Sidler, Corinne; Woycicki, Rafal; Yao, Youli; Kovalchuk, Igor

2013-07-01

The role of resistance (R) genes in plant pathogen interaction has been studied extensively due to its economical impact on agriculture. Interaction between tobacco mosaic virus (TMV) and the N protein from tobacco is one of the most widely used models to understand various aspects of pathogen resistance. The transcription activity governed by N gene promoter is one of the least understood elements of the model. In this study, the N gene promoter was cloned and fused with two different reporter genes, one encoding β-glucuronidase (N::GUS) and another, luciferase (N::LUC). Tobacco plants transformed with the N::GUS or N::LUC reporter constructs were screened for homozygosity and stable expression. Histochemical analysis of N::GUS tobacco plants revealed that the expression is organ specific and developmentally regulated. Whereas two week old plants expressed GUS in midveins only, 6-wk-old plants also expressed GUS in leaf lamella. Roots did not show GUS expression at any time during development. Experiments to address effects of external stress were performed using N::LUC tobacco plants. These experiments showed that N gene promoter expression was suppressed when plants were exposed to high but not low temperatures. Expression was also upregulated in response to TMV, but no changes were observed in plants treated with SA.

CpG promoter methylation of the ALKBH3 alkylation repair gene in breast cancer.

Science.gov (United States)

Stefansson, Olafur Andri; Hermanowicz, Stefan; van der Horst, Jasper; Hilmarsdottir, Holmfridur; Staszczak, Zuzanna; Jonasson, Jon Gunnlaugur; Tryggvadottir, Laufey; Gudjonsson, Thorkell; Sigurdsson, Stefan

2017-07-05

% CpG methylation was found to be statistically significantly associated with reduced survival (HR = 2.3; P = 0.012). By thresholding at the clinically relevant CpG methylation level (>20%), we find the incidence of ALKBH3 promoter methylation to be 5% (13 out of 265). ALKBH3 is a novel addition to the catalogue of DNA repair genes found inactivated in breast cancer. Our results underscore a link between defective alkylation repair and breast cancer which, additionally, is found in association with poor disease outcome.

Dissection of a locus on mouse chromosome 5 reveals arthritis promoting and inhibitory genes

DEFF Research Database (Denmark)

Lindvall, Therese; Karlsson, Jenny; Holmdahl, Rikard

2009-01-01

with Eae39 congenic- and sub-interval congenic mice, carrying RIIIS/J genes on the B10.RIII genetic background, revealed three loci within Eae39 that control disease and anti-collagen antibody titers. Two of the loci promoted disease and the third locus was protecting from collagen induced arthritis...... development. By further breeding of mice with small congenic fragments, we identified a 3.2 Megabasepair (Mbp) interval that regulates disease. CONCLUSIONS: Disease promoting- and protecting genes within the Eae39 locus on mouse chromosome 5, control susceptibility to collagen induced arthritis. A disease......-protecting locus in the telomeric part of Eae39 results in lower anti-collagen antibody responses. The study shows the importance of breeding sub-congenic mouse strains to reveal genetic effects on complex diseases....

Interleukin-10 gene promoter polymorphism as a potential host ...

African Journals Online (AJOL)

10) gene have been associated with altered levels of circulating IL-10, a Th2 cytokine that plays a key role in the pathogenesis of TB. We analyzed the frequencies of IL-10 promoter polymorphisms in 82 TB patients and 99 healthy Pakistani ...

Autoregulation of transcription of the hupA gene in Escherichia coli: evidence for steric hindrance of the functional promoter domains induced by HU.

Science.gov (United States)

Kohno, K; Yasuzawa, K; Hirose, M; Kano, Y; Goshima, N; Tanaka, H; Imamoto, F

1994-06-01

The molecular mechanism of autoregulation of expression of the hupA gene in Escherichia coli was examined. The promoter of the gene contains a palindromic sequence with the potential to form a cruciform DNA structure in which the -35 sequence lies at the base of the stem and the -10 sequence forms a single-stranded loop. An artificial promoter lacking the palindrome, which was constructed by replacing a 10 nucleotide repeat for the predicted cruciform arm by a sequence in the opposite orientation, was not subject to HU-repression. DNA relaxation induced by deleting HU proteins and/or inhibiting DNA gyrase in cells results in increased expression from the hupA promoter. We propose that initiation of transcription of the hupA gene is negatively regulated by steric hindrance of the functional promoter domains for formation of the cruciform configuration, which is facilitated at least in part by negative supercoiling of the hupA promoter DNA region. The promoter region of the hupB gene also contains a palindromic sequence that can assume a cruciform configuration. Negative regulation of this gene by HU proteins may occur by a mechanism similar to that operating for the hupA gene.

Development of radiation-inducible promoters for use in nitric oxide synthase gene therapy of cancer

International Nuclear Information System (INIS)

Hirst, D.G.; Worthington, J.; Adams, C.; Robson, T.; Scott, S.D.

2003-01-01

Full text: The free radical nitric oxide (NO) at nM concentrations performs multiple signaling roles that are essential for survival. These processes are regulated via the enzymes nNOS and eNOS, but another isoform, inducible nitric oxide synthase (iNOS) is capable of generating much higher concentrations (mM) over longer periods, resulting in the generation of very toxic species such as peroxynitrite. At high concentrations NO has many of the characteristics of an ideal anticancer molecule: it is cytotoxic (pro-apoptotic via peroxynitrite), it is a potent chemical radiosensitizer, it is anti-angiogenic and anti-metastatic. Thus, we see iNOS gene therapy as a strategy for targeting the generation of high concentrations of NO to tumours for therapeutic benefit. iNOS gene therapy should be used in combination with radiotherapy; so it is logical that the use of a radiation-inducible promoter should be part of the targeting strategy. We have tested several candidate promoters in vitro and in vivo. The WAF1 promoter has many of the properties desirable for therapeutic use including: rapid 3-4 fold induction at X-ray doses of 2 and 4Gy and no significant leakiness. WAF1 also has the advantage of being inducible by hypoxia and by the final product, NO. We have also tested the synthetic CArG promoter and demonstrated that, in addition to a high level of radiation inducibility, it is also inducible by NO. We have also been able to demonstrate potent radiosensitization (SER 2.0-2.5) in tumour cells in vitro and in vivo using iNOS gene transfer with constitutive or radiation-inducible promoters. We have also tested the use of iNOS gene therapy in combination with cisplatin and shown significant enhancement

THE ABERRANT PROMOTER HYPERMETHYLATION PATTERN OF THE ANTI - ANGIOGENIC TSP1 GENE IN EPITHELIAL OVARIAN CARCINOMA: AN INDIAN STUDY

Directory of Open Access Journals (Sweden)

Ramesh

2015-06-01

Full Text Available PURPOSE: The promoter hypermethylation patterns of Thrombospodin - 1 gene in 50 EOC patients were studied and the methylation pattern was correlated with various clinic pathological parameters. METHODS: The promoter hypermethylation pattern of the TSP - 1 gene was assessed using nested PCR and Methylation specific PCR. STATISTICAL ANALYSIS: All the available data was statistically analyzed using the Chi square test or Fisher Exact Test on the SPSS software version 22.0 and a value <0.0 5 was considered statistically significant. RESULTS: Forty of the fifty ovarian carcinoma samples reported positive for methylation corresponding to a methylation frequency of 80%. A methylation frequency of 89.2%, 83.3% and 42.8% was observed in malignant , Low malignant potential (borderline and benign sample cohorts. CONCLUSION: From the results drawn from this study, it clearly shows that the anti angiogenic protein TSP - 1 is extensively hypermethylated in ovarian carcinoma and that it accumulates over t he progression of the disease from benign to malignant. As previous reports suggest that there is no evidence of mutation of this gene, promoter hypermethylation may be a crucial factor for the down regulation of the gene. Further by clubbing together the promoter hypermethylation pattern of TSP - 1 gene with hypermethylation patterns of other TSG may provide a better insight into the application of using methylation profiles of TSG as a biomarker in the detection of ovarian carcinoma.

Paralogous SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL) genes differentially regulate leaf initiation and reproductive phase change in petunia.

Science.gov (United States)

Preston, Jill C; Jorgensen, Stacy A; Orozco, Rebecca; Hileman, Lena C

2016-02-01

Duplicated petunia clade-VI SPL genes differentially promote the timing of inflorescence and flower development, and leaf initiation rate. The timing of plant reproduction relative to favorable environmental conditions is a critical component of plant fitness, and is often associated with variation in plant architecture and habit. Recent studies have shown that overexpression of the microRNA miR156 in distantly related annual species results in plants with perennial characteristics, including late flowering, weak apical dominance, and abundant leaf production. These phenotypes are largely mediated through the negative regulation of a subset of genes belonging to the SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL) family of transcription factors. In order to determine how and to what extent paralogous SPL genes have partitioned their roles in plant growth and development, we functionally characterized petunia clade-VI SPL genes under different environmental conditions. Our results demonstrate that PhSBP1and PhSBP2 differentially promote discrete stages of the reproductive transition, and that PhSBP1, and possibly PhCNR, accelerates leaf initiation rate. In contrast to the closest homologs in annual Arabidopsis thaliana and Mimulus guttatus, PhSBP1 and PhSBP2 transcription is not mediated by the gibberellic acid pathway, but is positively correlated with photoperiod and developmental age. The developmental functions of clade-VI SPL genes have, thus, evolved following both gene duplication and speciation within the core eudicots, likely through differential regulation and incomplete sub-functionalization.

Molecular and functional characterization of the promoter of ETS2, the human c-ets-2 gene

International Nuclear Information System (INIS)

Mavrothalassitis, G.J.; Watson, D.K.; Papas, T.S.

1990-01-01

The 5' end of the human c-ets-2 gene, ETS2, was cloned and characterized. The major transcription initiation start sites were identified, and the pertinent sequences surrounding the ETS2 promoter were determined. The promoter region of ETS2 does not possess typical TATA and CAAT elements. However, this promoter contains several repeat regions, as well as two consensus AP2 binding sites and three putative Sp1 sites. There is also a palindromic region similar to the serum response element of the c-fos gene, located 1,400 base pairs (bp) upstream from the first major transcription initiation site. A G+C-rich sequence (GC element) with dyad symmetry can be seen in the ETS2 promoter, immediately following an unusually long polypurine-polypyrimidine tract. A series of deletion fragments from the putative promoter region were ligated in front of the bacterial chloramphenicol acetyltransferase gene and tested for activity following transfection into HeLa cells. The 5' boundary of the region needed for maximum promoter activity was found to be 159 bp upstream of the major initiation site. The promoter of ETS2 (within the polypyrimidine tract) serves to illustrate an alternative structure that may be present in genes with TATA-less promoters

The promoter of the glucoamylase-encoding gene of Aspergillus niger functions in Ustilago maydis

Energy Technology Data Exchange (ETDEWEB)

Smith, T.L. (Dept. of Agriculture, Madison, WI (United States) Univ. of Wisconsin, Madison (United States)); Gaskell, J.; Cullen, D. (Dept. of Agriculture, Madison, WI (United States)); Berka, R.M.; Yang, M.; Henner, D.J. (Genentech Inc., San Francisco, CA (United States))

1990-01-01

Promoter sequences from the Aspergillus niger glucoamylase-encoding gene (glaA) were linked to the bacterial hygromycin (Hy) phosphotransferase-encoding gene (hph) and this chimeric marker was used to select Hy-resistant (Hy[sup R]) Ustilago maydis transformants. This is an example of an Ascomycete promoter functioning in a Basidiomycete. Hy[sup R] transformants varied with respect to copy number of integrated vector, mitotic stability, and tolerance to Hy. Only 216 bp of glaA promoter sequence is required for expression in U. maydis but this promoter is not induced by starch as it is in Aspergillus spp. The transcription start points are the same in U. maydis and A. niger.

Specific expression of bioluminescence reporter gene in cardiomyocyte regulated by tissue specific promoter

Energy Technology Data Exchange (ETDEWEB)

Nguyen, Vu Hong; Tae, Seong Ho; Le, Nguyen Uyen Chi; Min, Jung Joon [Chonnam National University Medical School, Gwangju (Korea, Republic of)

2007-07-01

As the human heart is not capable of regenerating the great numbers of cardiac cells that are lost after myocardial infarction, impaired cardiac function is the inevitable result of ischemic disease. Recently, human embryonic stem cells (hESCs) have gained popularity as a potentially ideal cell candidate for tissue regeneration. In particular, hESCs are capable of cardiac lineage-specific differentiation and confer improvement of cardiac function following transplantation into animal models. Although such data are encouraging, the specific strategy for in vivo and non-invasive detection of differentiated cardiac lineage is still limited. Therefore, in the present study, we established the gene construction in which the optical reporter gene Firefly luciferase was controlled by Myosin Heavy Chain promoter for specific expressing in heart cells. The vector consisting of - MHC promoter and a firefly luciferase coding sequence flanked by full-length bovine growth hormone (BGH) 3'-polyadenylation sequence based on pcDNA3.1- vector backbone. To test the specific transcription of this promoter in g of MHC-Fluc or CMV-Flue (for control) plasmid DNA in myocardial tissue, 20 phosphate-buffered saline was directly injected into mouse myocardium through a midline sternotomy and liver. After 1 week of injection, MHC-Fluc expression was detected from heart region which was observed under cooled CCD camera of in vivo imaging system but not from liver. In control group injected with CMV-Flue, the bioluminescence was detected from all these organs. The expression of Flue under control of Myosin Heavy Chain promoter may become a suitable optical reporter gene for stem cell-derived cardiac lineage differentiation study.

Analysis of tissue-specific region in sericin 1 gene promoter of Bombyx mori

Energy Technology Data Exchange (ETDEWEB)

Yan, Liu [College of Biomedical Engineering and Instrument Science, Zhejiang University, Hangzhou 310027 (China); Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031 (China); Lian, Yu [College of Biomedical Engineering and Instrument Science, Zhejiang University, Hangzhou 310027 (China); Zhejiang Province Key Laboratory of Preventive Veterinary Medicine, Institute of Preventive Veterinary Medicine, Zhejiang University, Hangzhou 310029 (China); Xiuyang, Guo [Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031 (China); Tingqing, Guo [Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031 (China); Shengpeng, Wang [Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031 (China); Changde, Lu [Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031 (China)

2006-03-31

The gene encoding sericin 1 (Ser1) of silkworm (Bombyx mori) is specifically expressed in the middle silk gland cells. To identify element involved in this transcription-dependent spatial restriction, truncation of the 5' terminal from the sericin 1 (Ser1) promoter is studied in vivo. A 209 bp DNA sequence upstream of the transcriptional start site (-586 to -378) is found to be responsible for promoting tissue-specific transcription. Analysis of this 209 bp region by overlapping deletion studies showed that a 25 bp region (-500 to -476) suppresses the ectopic expression of the Ser1 promoter. An unknown factor abundant in fat body nuclear extracts is shown to bind to this 25 bp fragment. These results suggest that this 25 bp region and the unknown factor are necessary for determining the tissue-specificity of the Ser1 promoter.

Induction and maintenance of DNA methylation in plant promoter sequences by apple latent spherical virus-induced transcriptional gene silencing

Directory of Open Access Journals (Sweden)

Tatsuya eKon

2014-11-01

Full Text Available Apple latent spherical virus (ALSV is an efficient virus-induced gene silencing vector in functional genomics analyses of a broad range of plant species. Here, an Agrobacterium-mediated inoculation (agroinoculation system was developed for the ALSV vector, and virus-induced transcriptional gene silencing (VITGS is described in plants infected with the ALSV vector. The cDNAs of ALSV RNA1 and RNA2 were inserted between the CaMV 35S promoter and the NOS-T sequences in a binary vector pCAMBIA1300 to produce pCALSR1 and pCALSR2-XSB or pCALSR2-XSB/MN. When these vector constructs were agroinoculated into Nicotiana benthamiana plants with a construct expressing a viral silencing suppressor, the infection efficiency of the vectors was 100%. A recombinant ALSV vector carrying part of the 35S promoter sequence induced transcriptional gene silencing of the green fluorescent protein gene in a line of N. benthamiana plants, resulting in the disappearance of green fluorescence of infected plants. Bisulfite sequencing showed that cytosine residues at CG and CHG sites of the 35S promoter sequence were highly methylated in the silenced generation 0 plants infected with the ALSV carrying the promoter sequence as well as in progeny. The ALSV-mediated VITGS state was inherited by progeny for multiple generations. In addition, induction of VITGS of an endogenous gene (chalcone synthase-A was demonstrated in petunia plants infected with an ALSV vector carrying the native promoter sequence. These results suggest that ALSV-based vectors can be applied to study DNA methylation in plant genomes, and provide a useful tool for plant breeding via epigenetic modification.

A cII-dependent promoter is located within the Q gene of bacteriophage lambda.

OpenAIRE

Hoopes, B C; McClure, W R

1985-01-01

We have found a cII-dependent promoter, PaQ, within the Q gene of bacteriophage lambda. Transcription experiments and abortive initiation assays performed in vitro showed that the promoter strength and the cII affinity of PaQ were comparable to the other cII-dependent lambda promoters, PE and PI. The location and leftward direction of PaQ suggests a possible role in the delay of lambda late-gene expression by cII protein, a phenomenon that has been called cII-dependent inhibition. We have con...

Identification of a second flagellin gene and functional characterization of a sigma70-like promoter upstream of a Leptospira borgpetersenii flaB gene.

Science.gov (United States)

Lin, Min; Dan, Hanhong; Li, Yijing

2004-02-01

Leptospira borgpetersenii, one of the causative agents of leptospirosis in both animals and humans, is a bacterial pathogen with characteristic motility that is mediated by the rotation of two periplasmic flagella (PF). The flaB gene coding for a core polypeptide subunit of PF was previously characterized by sequence analysis of its open reading frame (ORF) (M. Lin, J Biochem Mol Biol Biophys 2:181-187, 1999). The present study was undertaken to isolate and clone the uncharacterized sequence upstream of the flaB gene by using a PCR-based genome walking procedure. This has resulted in a 1470-bp genomic DNA sequence in which an 846-bp ORF coding for a 281-amino acid polypeptide (31.3 kDa) is identified 455 bp upstream from the flaB start codon. The encoded protein exhibits 72% amino acid identity to the deduced FlaB protein sequence of L. borgpetersenii and a high degree of sequence homology to the FlaB proteins of other spirochaetes. This has demonstrated for the first time that a second flaB gene homolog is present in a Leptospira species. The newly identified gene is designated flaB1, and the previously cloned flaB renamed flaB2. Within the intergenic sequence between flaB1 and flaB2, a potential stem-loop structure (12-bp inverted repeats) was identified 25 bp downstream of the flaB1 stop codon; this could serve as a transcription terminator for the flaB1 mRNA. Three E. coli-like promoter regions (I, II, and III) for binding Esigma(70), a regulatory sequence uncommonly found in flagellar genes, were predicted upstream of the flaB2 ORF. Only promoter region II contains a promoter that is functional in E. coli, as revealed at phenotypic and transcriptional levels by its capability of directing the expression of the chloramphenicol acetyltransferase (CAT) gene in the promoter probe vector pKK232-8. These observations may suggest that flaB1 and flaB2 are transcribed separately and do not form a transcriptional operon controlled by a single promoter.

Promoter Methylation Analysis of IDH Genes in Human Gliomas

International Nuclear Information System (INIS)

Flanagan, Simon; Lee, Maggie; Li, Cheryl C. Y.; Suter, Catherine M.; Buckland, Michael E.

2012-01-01

Mutations in isocitrate dehydrogenase (IDH)-1 or -2 are found in the majority of WHO grade II and III astrocytomas and oligodendrogliomas, and secondary glioblastomas. Almost all described mutations are heterozygous missense mutations affecting a conserved arginine residue in the substrate binding site of IDH1 (R132) or IDH2 (R172). But the exact mechanism of IDH mutations in neoplasia is not understood. It has been proposed that IDH mutations impart a “toxic gain-of-function” to the mutant protein, however a dominant-negative effect of mutant IDH has also been described, implying that IDH may function as a tumor suppressor gene. As most, if not all, tumor suppressor genes are inactivated by epigenetic silencing, in a wide variety of tumors, we asked if IDH1 or IDH2 carry the epigenetic signature of a tumor suppressor by assessing cytosine methylation at their promoters. Methylation was quantified in 68 human brain tumors, including both IDH-mutant and IDH wildtype, by bisulfite pyrosequencing. In all tumors examined, CpG methylation levels were less than 8%. Our data demonstrate that inactivation of IDH function through promoter hypermethylation is not common in human gliomas and other brain tumors. These findings do not support a tumor suppressor role for IDH genes in human gliomas.

Erythroid Kruppel-like factor (EKLF) is recruited to the γ-globin gene promoter as a co-activator and is required for γ-globin gene induction by short-chain fatty acid derivatives

Science.gov (United States)

Perrine, Susan P.; Mankidy, Rishikesh; Boosalis, Michael S.; Bieker, James J.; Faller, Douglas V.

2011-01-01

Objectives The erythroid Kruppel-like factor (EKLF) is an essential transcription factor for β-type globin gene switching, and specifically activates transcription of the adult β-globin gene promoter. We sought to determine if EKLF is also required for activation of the γ-globin gene by short-chain fatty acid (SCFA) derivatives, which are now entering clinical trials. Methods The functional and physical interaction of EKLF and co-regulatory molecules with the endogenous human globin gene promoters was studied in primary human erythroid progenitors and cell lines, using chromatin immunoprecipitation (ChIP) assays and genetic manipulation of the levels of EKLF and co-regulators. Results and conclusions Knockdown of EKLF prevents SCFA-induced expression of the γ-globin promoter in a stably expressed μLCRβprRlucAγprFluc cassette, and prevents induction of the endogenous γ-globin gene in primary human erythroid progenitors. EKLF is actively recruited to endogenous γ-globin gene promoters after exposure of primary human erythroid progenitors, and murine hematopoietic cell lines, to SCFA derivatives. The core ATPase BRG1 subunit of the human SWI/WNF complex, a ubiquitous multimeric complex that regulates gene expression by remodeling nucleosomal structure, is also required for γ-globin gene induction by SCFA derivatives. BRG1 is actively recruited to the endogenous γ-globin promoter of primary human erythroid progenitors by exposure to SCFA derivatives, and this recruitment is dependent upon the presence of EKLF. These findings demonstrate that EKLF, and the co-activator BRG1, previously demonstrated to be required for definitive or adult erythropoietic patterns of globin gene expression, are co-opted by SCFA derivatives to activate the fetal globin genes. PMID:19220418

Clinical Utility of promoter methylation of the tumor suppressor genes DKK3, and RASSF1A in breast cancer patients

Directory of Open Access Journals (Sweden)

Marwa H. Saied

2018-04-01

Full Text Available Background: DNA methylation is the commonest known epigenetic change that results in silencing of tumor suppressor genes. Promoter methylation of tumor suppressor genes has the potential for early detection of breast cancer. Aim: Aim is to examine the potential usefulness of blood based methylation specific polymerase chain reaction (MSP of methylated DKK3 and RASSF1A genes in early detection of breast cancer. Method: Methylation status of DKK3 and RASSF1 was investigated in forty breast cancer patients, twenty fibroadenoma patients and twenty healthy ladies as control group using MSP. Results: Methylation of DKK3 promoter was found in 22.5% of breast cancer patients, while DKK3 methylation was absent in both fibroadenoma patients and control group. Similarly, methylation of RASSF1 promoter was found in 17.5% of breast cancer patients and in none of fibroadenoma and control group. Conclusion: Promoter methylation of DKK3 and RASSF1 was found in breast cancer patients while absent in control group suggesting that tumorspecific methylation of the two genes (DKK3 and RASSF1A might be a valuable biomarker for the early detection of breast cancer. Keywords: DNA methylation, Breast cancer, DKK3, RASSF1

Comparative analysis of myostatin gene and promoter sequences of Qinchuan and Red Angus cattle.

Science.gov (United States)

He, Y L; Wu, Y H; Quan, F S; Liu, Y G; Zhang, Y

2013-09-04

To better understand the function of the myostatin gene and its promoter region in bovine, we amplified and sequenced the myostatin gene and promoter from the blood of Qinchuan and Red Angus cattle by using polymerase chain reaction. The sequences of Qinchuan and Red Angus cattle were compared with those of other cattle breeds available in GenBank. Exon splice sites were confirmed by mRNA sequencing. Compared to the published sequence (GenBank accession No. AF320998), 69 single nucleotide polymorphisms (SNPs) were identified in the Qinchuan myostatin gene, only one of which was an insertion mutation in Qinchuan cattle. There was a 16-bp insertion in the first 705-bp intron in 3 Qinchuan cattle. A total of 7 SNPs were identified in exon 3, in which the mutation occurred in the third base of the codon and was synonymous. On comparing the Qinchuan myostatin gene sequence to that of Red Angus cattle, a total of 50 SNPs were identified in the first and third exons. In addition, there were 18 SNPs identified in the Qinchuan cattle promoter region compared with those of other cattle compared to the Red Angus cattle myostatin promoter region. breeds (GenBank accession No. AF348479), but only 14 SNPs when compared to the Red Angus cattle myostatin promoter region.

Polymorphisms in promoter sequences of MDM2, p53, and p16INK4a genes in normal Japanese individuals

Directory of Open Access Journals (Sweden)

Yasuhito Ohsaka

2010-01-01

Full Text Available Research has been conducted to identify sequence polymorphisms of gene promoter regions in patients and control subjects, including normal individuals, and to determine the influence of these polymorphisms on transcriptional regulation in cells that express wild-type or mutant p53. In this study we isolated genomic DNA from whole blood of healthy Japanese individuals and sequenced the promoter regions of the MDM2, p53, and p16INK4a genes. We identified polymorphisms comprising 3 nucleotide substitutions at exon 1 and intron 1 regions of the MDM2 gene and 1 nucleotide insertion at a poly(C nucleotide position in the p53 gene. The Japanese individuals also exhibited p16INK4a polymorphisms at several positions, including position -191. Reporter gene analysis by using luciferase revealed that the polymorphisms of MDM2, p53, and p16INK4a differentially altered luciferase activities in several cell lines, including the Colo320DM, U251, and T98G cell lines expressing mutant p53. Our results indicate that the promoter sequences of these genes differ among normal Japanese individuals and that polymorphisms can alter gene transcription activity.

Gap junctional communication modulates gene transcription by altering the recruitment of Sp1 and Sp3 to connexin-response elements in osteoblast promoters

Science.gov (United States)

Stains, Joseph P.; Lecanda, Fernando; Screen, Joanne; Towler, Dwight A.; Civitelli, Roberto

2003-01-01

Loss-of-function mutations of gap junction proteins, connexins, represent a mechanism of disease in a variety of tissues. We have shown that recessive (gene deletion) or dominant (connexin45 overexpression) disruption of connexin43 function results in osteoblast dysfunction and abnormal expression of osteoblast genes, including down-regulation of osteocalcin transcription. To elucidate the molecular mechanisms of gap junction-sensitive transcriptional regulation, we systematically analyzed the rat osteocalcin promoter for sensitivity to gap junctional intercellular communication. We identified an Sp1/Sp3 containing complex that assembles on a minimal element in the -70 to -57 region of the osteocalcin promoter in a gap junction-dependent manner. This CT-rich connexin-response element is necessary and sufficient to confer gap junction sensitivity to the osteocalcin proximal promoter. Repression of osteocalcin transcription occurs as a result of displacement of the stimulatory Sp1 by the inhibitory Sp3 on the promoter when gap junctional communication is perturbed. Modulation of Sp1/Sp3 recruitment also occurs on the collagen Ialpha1 promoter and translates into gap junction-sensitive transcriptional control of collagen Ialpha1 gene expression. Thus, regulation of Sp1/Sp3 recruitment to the promoter may represent a potential general mechanism for transcriptional control of target genes by signals passing through gap junctions.

c-Myc activates BRCA1 gene expression through distal promoter elements in breast cancer cells

International Nuclear Information System (INIS)

Chen, Yinghua; Xu, Jinhua; Borowicz, Stanley; Collins, Cindy; Huo, Dezheng; Olopade, Olufunmilayo I

2011-01-01

The BRCA1 gene plays an important role in the maintenance of genomic stability. BRCA1 inactivation contributes to breast cancer tumorigenesis. An increasing number of transcription factors have been shown to regulate BRCA1 expression. c-Myc can act as a transcriptional activator, regulating up to 15% of all genes in the human genome and results from a high throughput screen suggest that BRCA1 is one of its targets. In this report, we used cultured breast cancer cells to examine the mechanisms of transcriptional activation of BRCA1 by c-Myc. c-Myc was depleted using c-Myc-specific siRNAs in cultured breast cancer cells. BRCA1 mRNA expression and BRCA1 protein expression were determined by quantitative RT-PCR and western blot, respectively and BRCA1 promoter activities were examined under these conditions. DNA sequence analysis was conducted to search for high similarity to E boxes in the BRCA1 promoter region. The association of c-Myc with the BRCA1 promoter in vivo was tested by a chromatin immunoprecipitation assay. We investigated the function of the c-Myc binding site in the BRCA1 promoter region by a promoter assay with nucleotide substitutions in the putative E boxes. BRCA1-dependent DNA repair activities were measured by a GFP-reporter assay. Depletion of c-Myc was found to be correlated with reduced expression levels of BRCA1 mRNA and BRCA1 protein. Depletion of c-Myc decreased BRCA1 promoter activity, while ectopically expressed c-Myc increased BRCA1 promoter activity. In the distal BRCA1 promoter, DNA sequence analysis revealed two tandem clusters with high similarity, and each cluster contained a possible c-Myc binding site. c-Myc bound to these regions in vivo. Nucleotide substitutions in the c-Myc binding sites in these regions abrogated c-Myc-dependent promoter activation. Furthermore, breast cancer cells with reduced BRCA1 expression due to depletion of c-Myc exhibited impaired DNA repair activity. The distal BRCA1 promoter region is associated with c

A Dual-Promoter Gene Orchestrates the Sucrose-Coordinated Synthesis of Starch and Fructan in Barley

Energy Technology Data Exchange (ETDEWEB)

Jin, Yunkai; Fei, Mingliang; Rosenquist, Sara; Jin, Lu; Gohil, Suresh; Sandström, Corine; Olsson, Helena; Persson, Cecilia; Höglund, Anna-Stina; Fransson, Gunnel; Ruan, Ying; Åman, Per; Jansson, Christer; Liu, Chunlin; Andersson, Roger; Sun, Chuanxin

2017-12-01

Starch and fructan are two important carbohydrates in many flowering plants and in human diets. Understanding how plants allocate photosynthates and how they prioritize synthesis of different carbohydrates during development is essential in efforts to improve cereals for increased stress tolerance and for desirable carbohydrate compositions in food and feed. We report the coordinated synthesis of starch and fructan in barley, orchestrated by two functionally opposing transcription factors encoded from two alternative promoters, one intronic/exonic, harbored on a single gene. . This dual-transcription factor system employs an autoregulatory, antagonsitic mechanism in sensing sucrose at one promoter, potentially via sucrose/glucose/fructose/trehalose 6-phosphate signaling, and conduct a coordinated synthesis of starch and fructan synthesis by competitive transcription factor binding to the second promoter The finding of an intron/exon-spanning promoter in a hosting gene, resulting in proteins with distinct functions, contributes to our appreciation of the complexity of the plant genome As a case in point for the physiological role of the antagonistic transcription factor system, we have demonstrated that it can be exploited in breeding barley with tailored amounts of fructan for production of specialty food ingredients.

DNA demethylases target promoter transposable elements to positively regulate stress responsive genes in Arabidopsis.

Science.gov (United States)

Le, Tuan-Ngoc; Schumann, Ulrike; Smith, Neil A; Tiwari, Sameer; Au, Phil Chi Khang; Zhu, Qian-Hao; Taylor, Jennifer M; Kazan, Kemal; Llewellyn, Danny J; Zhang, Ren; Dennis, Elizabeth S; Wang, Ming-Bo

2014-09-17

DNA demethylases regulate DNA methylation levels in eukaryotes. Arabidopsis encodes four DNA demethylases, DEMETER (DME), REPRESSOR OF SILENCING 1 (ROS1), DEMETER-LIKE 2 (DML2), and DML3. While DME is involved in maternal specific gene expression during seed development, the biological function of the remaining DNA demethylases remains unclear. We show that ROS1, DML2, and DML3 play a role in fungal disease resistance in Arabidopsis. A triple DNA demethylase mutant, rdd (ros1 dml2 dml3), shows increased susceptibility to the fungal pathogen Fusarium oxysporum. We identify 348 genes differentially expressed in rdd relative to wild type, and a significant proportion of these genes are downregulated in rdd and have functions in stress response, suggesting that DNA demethylases maintain or positively regulate the expression of stress response genes required for F. oxysporum resistance. The rdd-downregulated stress response genes are enriched for short transposable element sequences in their promoters. Many of these transposable elements and their surrounding sequences show localized DNA methylation changes in rdd, and a general reduction in CHH methylation, suggesting that RNA-directed DNA methylation (RdDM), responsible for CHH methylation, may participate in DNA demethylase-mediated regulation of stress response genes. Many of the rdd-downregulated stress response genes are downregulated in the RdDM mutants nrpd1 and nrpe1, and the RdDM mutants nrpe1 and ago4 show enhanced susceptibility to F. oxysporum infection. Our results suggest that a primary function of DNA demethylases in plants is to regulate the expression of stress response genes by targeting promoter transposable element sequences.

Association of Interleukin-10 gene promoter polymorphisms with obstructive sleep apnea.

Science.gov (United States)

Özdaş, Sibel; Özdaş, Talih; Acar, Mustafa; Erbek, Selim S; Köseoğlu, Sabri; Göktürk, Gökhan; Izbirak, Afife

2016-05-01

Interleukin-10 (IL) is an anti-inflammatory cytokine that regulates normal sleep patterns, and recent studies have reported that it is a potential useful biomarker to identify presence and severity of sleep apnea syndrome (OSAS). Promoter polymorphisms of IL-10 gene have been associated with altered expression levels, which contributes to OSAS. The aim of this study was to determine the prevalence of -1082 G/A, -819 C/T, and -592 C/A promoter polymorphisms of IL-10 gene in individuals with OSAS and controls. An open-label study was performed in the Otorhinolaryngology and Sleep Disorders Outpatient Clinics. One hundred four cases with OSAS were included as the study group, and 78 individuals without OSAS were included as the controls. DNAs were extracted from peripheral blood leukocytes, and the sites that encompassed those polymorphisms were identified by DNA sequencing analyses. Data were analyzed with SNPStats and multifactor dimensionality reduction (MDR) software. The prevalence of OSAS was higher in males in the study group when compared to controls (P = 0.0003). The IL-10-1082 G/A, -819 C/T, and -592 C/A SNPs, and their minor alleles were associated with a significantly increased risk for OSAS compared to the controls (P ˂ 0.05 for all). Furthermore, ATA haplotype frequency was significantly higher in the study group compared to the control group, but the GCC haplotype frequency was lower (P = 0.0001 and P = 0.0001). As indicated in MDR analysis, combinations of IL-10 gene were associated with OSAS in single-, double-, and triple-locus analyses. The prevalences of the IL-10 gene promoter polymorphisms were different in OSAS patients and the controls in Turkish population. IL-10 gene polymorphisms may lead to altered inflammatory cascade, which might contribute to OSAS. Further studies on larger cohorts are needed to validate our findings.

SNP variation in the promoter of the PRKAG3 gene and association with meat quality traits in pig

Directory of Open Access Journals (Sweden)

Ryan Marion T

2012-07-01

Full Text Available Abstract Background The PRKAG3 gene encodes the γ3 subunit of adenosine monophosphate activated protein kinase (AMPK, a protein that plays a key role in energy metabolism in skeletal muscle. Non-synonymous single nucleotide polymorphisms (SNPs in this gene such as I199V are associated with important pork quality traits. The objective of this study was to investigate the relationship between gene expression of the PRKAG3 gene, SNP variation in the PRKAG3 promoter and meat quality phenotypes in pork. Results PRKAG3 gene expression was found to correlate with a number of traits relating to glycolytic potential (GP and intramuscular fat (IMF in three phenotypically diverse F1 crosses comprising of 31 Large White, 23 Duroc and 32 Pietrain sire breeds. The majority of associations were observed in the Large White cross. There was a significant association between genotype at the g.-311A>G locus and PRKAG3 gene expression in the Large White cross. In the same population, ten novel SNPs were identified within a 1.3 kb region spanning the promoter and from this three major haplotypes were inferred. Two tagging SNPs (g.-995A>G and g.-311A>G characterised the haplotypes within the promoter region being studied. These two SNPs were subsequently genotyped in larger populations consisting of Large White (n = 98, Duroc (n = 99 and Pietrain (n = 98 purebreds. Four major haplotypes including promoter SNP’s g.-995A>G and g.-311A>G and I199V were inferred. In the Large White breed, HAP1 was associated with IMF% in the M. longissmus thoracis et lumborum (LTL and driploss%. HAP2 was associated with IMFL% GP-influenced traits pH at 24 hr in LTL (pHULT, pH at 45 min in LTL (pH45LT and pH at 45 min in the M. semimembranosus muscle (pH45SM. HAP3 was associated with driploss%, pHULT pH45LT and b* Minolta. In the Duroc breed, associations were observed between HAP1 and driploss% and pHUSM. No associations were observed with the remaining haplotypes (HAP2

Characterization of a putative cis-regulatory element that controls transcriptional activity of the pig uroplakin II gene promoter

International Nuclear Information System (INIS)

Kwon, Deug-Nam; Park, Mi-Ryung; Park, Jong-Yi; Cho, Ssang-Goo; Park, Chankyu; Oh, Jae-Wook; Song, Hyuk; Kim, Jae-Hwan; Kim, Jin-Hoi

2011-01-01

Highlights: → The sequences of -604 to -84 bp of the pUPII promoter contained the region of a putative negative cis-regulatory element. → The core promoter was located in the 5F-1. → Transcription factor HNF4 can directly bind in the pUPII core promoter region, which plays a critical role in controlling promoter activity. → These features of the pUPII promoter are fundamental to development of a target-specific vector. -- Abstract: Uroplakin II (UPII) is a one of the integral membrane proteins synthesized as a major differentiation product of mammalian urothelium. UPII gene expression is bladder specific and differentiation dependent, but little is known about its transcription response elements and molecular mechanism. To identify the cis-regulatory elements in the pig UPII (pUPII) gene promoter region, we constructed pUPII 5' upstream region deletion mutants and demonstrated that each of the deletion mutants participates in controlling the expression of the pUPII gene in human bladder carcinoma RT4 cells. We also identified a new core promoter region and putative negative cis-regulatory element within a minimal promoter region. In addition, we showed that hepatocyte nuclear factor 4 (HNF4) can directly bind in the pUPII core promoter (5F-1) region, which plays a critical role in controlling promoter activity. Transient cotransfection experiments showed that HNF4 positively regulates pUPII gene promoter activity. Thus, the binding element and its binding protein, HNF4 transcription factor, may be involved in the mechanism that specifically regulates pUPII gene transcription.

Quantitative Methylation Profiles for Multiple Tumor Suppressor Gene Promoters in Salivary Gland Tumors

Science.gov (United States)

Durr, Megan L.; Mydlarz, Wojciech K.; Shao, Chunbo; Zahurak, Marianna L.; Chuang, Alice Y.; Hoque, Mohammad O.; Westra, William H.; Liegeois, Nanette J.; Califano, Joseph A.; Sidransky, David; Ha, Patrick K.

2010-01-01

Background Methylation profiling of tumor suppressor gene (TSGs) promoters is quickly becoming a powerful diagnostic tool for the early detection, prognosis, and even prediction of clinical response to treatment. Few studies address this in salivary gland tumors (SGTs); hence the promoter methylation profile of various TSGs was quantitatively assessed in primary SGT tissue to determine if tumor-specific alterations could be detected. Methodology DNA isolated from 78 tumor and 17 normal parotid gland specimens was assayed for promoter methylation status of 19 TSGs by fluorescence-based, quantitative methylation-specific PCR (qMSP). The data were utilized in a binary fashion as well as quantitatively (using a methylation quotient) allowing for better profiling and interpretation of results. Principal Findings The average number of methylation events across the studied genes was highest in salivary duct carcinoma (SDC), with a methylation value of 9.6, compared to the normal 4.5 (ptrend for increasing methylation in APC, Mint 1, PGP9.5, RAR-β, and Timp3. Conclusions/Significance Screening promoter methylation profiles in SGTs showed considerable heterogeneity. The methylation status of certain markers was surprisingly high in even normal salivary tissue, confirming the need for such controls. Several TSGs were found to be associated with malignant SGTs, especially SDC. Further study is needed to evaluate the potential use of these associations in the detection, prognosis, and therapeutic outcome of these rare tumors. PMID:20520817

Developmental Functions of miR156-Regulated SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL) Genes in Arabidopsis thaliana.

Science.gov (United States)

Xu, Mingli; Hu, Tieqiang; Zhao, Jianfei; Park, Mee-Yeon; Earley, Keith W; Wu, Gang; Yang, Li; Poethig, R Scott

2016-08-01

Correct developmental timing is essential for plant fitness and reproductive success. Two important transitions in shoot development-the juvenile-to-adult vegetative transition and the vegetative-to-reproductive transition-are mediated by a group of genes targeted by miR156, SQUAMOSA PROMOTER BINDING PROTEIN (SBP) genes. To determine the developmental functions of these genes in Arabidopsis thaliana, we characterized their expression patterns, and their gain-of-function and loss-of-function phenotypes. Our results reveal that SBP-LIKE (SPL) genes in Arabidopsis can be divided into three functionally distinct groups: 1) SPL2, SPL9, SPL10, SPL11, SPL13 and SPL15 contribute to both the juvenile-to-adult vegetative transition and the vegetative-to-reproductive transition, with SPL9, SP13 and SPL15 being more important for these processes than SPL2, SPL10 and SPL11; 2) SPL3, SPL4 and SPL5 do not play a major role in vegetative phase change or floral induction, but promote the floral meristem identity transition; 3) SPL6 does not have a major function in shoot morphogenesis, but may be important for certain physiological processes. We also found that miR156-regulated SPL genes repress adventitious root development, providing an explanation for the observation that the capacity for adventitious root production declines as the shoot ages. miR156 is expressed at very high levels in young seedlings, and declines in abundance as the shoot develops. It completely blocks the expression of its SPL targets in the first two leaves of the rosette, and represses these genes to different degrees at later stages of development, primarily by promoting their translational repression. These results provide a framework for future studies of this multifunctional family of transcription factors, and offer new insights into the role of miR156 in Arabidopsis development.

Pgas, a Low-pH-Induced Promoter, as a Tool for Dynamic Control of Gene Expression for Metabolic Engineering of Aspergillus niger.

Science.gov (United States)

Yin, Xian; Shin, Hyun-Dong; Li, Jianghua; Du, Guocheng; Liu, Long; Chen, Jian

2017-03-15

The dynamic control of gene expression is important for adjusting fluxes in order to obtain desired products and achieve appropriate cell growth, particularly when the synthesis of a desired product drains metabolites required for cell growth. For dynamic gene expression, a promoter responsive to a particular environmental stressor is vital. Here, we report a low-pH-inducible promoter, P gas , which promotes minimal gene expression at pH values above 5.0 but functions efficiently at low pHs, such as pH 2.0. First, we performed a transcriptional analysis of Aspergillus niger , an excellent platform for the production of organic acids, and we found that the promoter P gas may act efficiently at low pH. Then, a gene for synthetic green fluorescent protein ( sGFP ) was successfully expressed by P gas at pH 2.0, verifying the results of the transcriptional analysis. Next, P gas was used to express the cis -aconitate decarboxylase ( cad ) gene of Aspergillus terreus in A. niger , allowing the production of itaconic acid at a titer of 4.92 g/liter. Finally, we found that P gas strength was independent of acid type and acid ion concentration, showing dependence on pH only. IMPORTANCE The promoter P gas can be used for the dynamic control of gene expression in A. niger for metabolic engineering to produce organic acids. This promoter may also be a candidate tool for genetic engineering. Copyright © 2017 American Society for Microbiology.

Lactoferrin gene promoter variants and their association with clinical and subclinical mastitis in indigenous and crossbred cattle.

Science.gov (United States)

Chopra, A; Gupta, I D; Verma, A; Chakravarty, A K; Vohra, V

2015-01-01

Lactoferrin (Lf) gene promoter was screened for the presence of single nucleotide polymphism in indigenous and crossbred cattle from North India and to evaluate its association with Mastitis. Study revealed the presence of genetic variation in regulatory region of bovine Lactoferrin gene using PCR-RFLP technique. Three genotypes namely GG, GH and HH were identified. A single nucleotide change, from guanine to adenine at 25th position was found to be significantly associated (pmastitis in indigenous Sahiwal and crossbred Karan Fries cattle maintained at organised herd of National Dairy Research Institute, Karnal. A non-significant association was observed between subclinical mastitis, somatic cell score (SCS), and GG genotype in Karan Fries cattle, however, a lower SCS was observed in animals having GG genotype. Overall a lower incidence of clinical mastitis was recorded in those animals having GG genotype of Lf in Sahiwal and Karan Fries (KF) cattle. The SNP identified in the promoter region may effect expression lactoferrin protein, which may lead to different levels of antibacterial and anti-inflammatory activity of Lf gene. Results from this study indicated the probable role played by Lactoferrin promoter to serve as candidate gene for mastitis susceptibility among indigenous and crossbred milch cattle.

Study of the Role of siRNA Mediated Promoter Methylation in DNMT3B Knockdown and Alteration of Promoter Methylation of CDH1, GSTP1 Genes in MDA-MB -453 Cell Line.

Science.gov (United States)

Naghitorabi, Mojgan; Mir Mohammad Sadeghi, Hamid; Mohammadi Asl, Javad; Rabbani, Mohammad; Jafarian-Dehkordi, Abbas

2017-01-01

Promoter methylation is one of the main epigenetic mechanisms that leads to the inactivation of tumor suppressor genes during carcinogenesis. Due to the reversible nature of DNA methylation, many studies have been performed to correct theses epigenetic defects by inhibiting DNA methyltransferases (DNMTs). In this case novel therapeutics especially siRNA oligonucleotides have been used to specifically knock down the DNMTs at mRNA level. Also many studies have focused on transcriptional gene silencing in mammalian cells via siRNA mediated promoter methylation. The present study was designed to assess the role of siRNA mediated promoter methylation in DNMT3B knockdown and alteration of promoter methylation of Cadherin-1 (CDH1), Glutathione S-Transferase Pi 1(GSTP1), and DNMT3B genes in MDA-MB-453 cell line. MDA-MB-453 cells were transfected with siDNMT targeting DNMT3B promoter and harvested at 24 and 48 h post transfection to monitor gene silencing and promoter methylation respectively. DNMT3B expression was monitored by quantitative RT-PCR method. Promoter methylation was quantitatively evaluated using differential high resolution melting analysis. A non-significant 20% reduction in DNMT3B mRNA level was shown only after first transfection with siDNMT, which was not reproducible. Promoter methylation levels of DNMT3B, CDH1, and GSTP1 were detected at about 15%, 70% and 10% respectively, in the MDA-MB-453 cell line, with no significant change after transfection. Our results indicated that siDNMT sequence were not able to affect promoter methylation and silencing of DNMT3B in MDA-MB-453 cells. However, quantitation of methylation confirmed a hypermethylated phenotype at CDH1 and GSTP1 promoters as well as a differential methylation pattern at DNMT3B promoter in breast cancer.

Medicago truncatula SOC1 Genes Are Up-regulated by Environmental Cues That Promote Flowering

Directory of Open Access Journals (Sweden)

Jared B. Fudge

2018-04-01

Full Text Available Like Arabidopsis thaliana, the flowering of the legume Medicago truncatula is promoted by long day (LD photoperiod and vernalization. However, there are differences in the molecular mechanisms involved, with orthologs of two key Arabidopsis thaliana regulators, FLOWERING LOCUS C (FLC and CONSTANS (CO, being absent or not having a role in flowering time function in Medicago. In Arabidopsis, the MADS-box transcription factor gene, SUPPRESSOR OF OVEREXPRESSION OF CONSTANS 1 (AtSOC1, plays a key role in integrating the photoperiodic and vernalization pathways. In this study, we set out to investigate whether the Medicago SOC1 genes play a role in regulating flowering time. Three Medicago SOC1 genes were identified and characterized (MtSOC1a–MtSOC1c. All three MtSOC1 genes, when heterologously expressed, were able to promote earlier flowering of the late-flowering Arabidopsis soc1-2 mutant. The three MtSOC1 genes have different patterns of expression. However, consistent with a potential role in flowering time regulation, all three MtSOC1 genes are expressed in the shoot apex and are up-regulated in the shoot apex of plants in response to LD photoperiods and vernalization. The up-regulation of MtSOC1 genes was reduced in Medicago fta1-1 mutants, indicating that they are downstream of MtFTa1. Insertion mutant alleles of Medicago soc1b do not flower late, suggestive of functional redundancy among Medicago SOC1 genes in promoting flowering.

Characterization of Soybean WRKY Gene Family and Identification of Soybean WRKY Genes that Promote Resistance to Soybean Cyst Nematode.

Science.gov (United States)

Yang, Yan; Zhou, Yuan; Chi, Yingjun; Fan, Baofang; Chen, Zhixiang

2017-12-19

WRKY proteins are a superfamily of plant transcription factors with important roles in plants. WRKY proteins have been extensively analyzed in plant species including Arabidopsis and rice. Here we report characterization of soybean WRKY gene family and their functional analysis in resistance to soybean cyst nematode (SCN), the most important soybean pathogen. Through search of the soybean genome, we identified 174 genes encoding WRKY proteins that can be classified into seven groups as established in other plants. WRKY variants including a WRKY-related protein unique to legumes have also been identified. Expression analysis reveals both diverse expression patterns in different soybean tissues and preferential expression of specific WRKY groups in certain tissues. Furthermore, a large number of soybean WRKY genes were responsive to salicylic acid. To identify soybean WRKY genes that promote soybean resistance to SCN, we first screened soybean WRKY genes for enhancing SCN resistance when over-expressed in transgenic soybean hairy roots. To confirm the results, we transformed five WRKY genes into a SCN-susceptible soybean cultivar and generated transgenic soybean lines. Transgenic soybean lines overexpressing three WRKY transgenes displayed increased resistance to SCN. Thus, WRKY genes could be explored to develop new soybean cultivars with enhanced resistance to SCN.

Characterization of the bovine pregnancy-associated glycoprotein gene family – analysis of gene sequences, regulatory regions within the promoter and expression of selected genes

Directory of Open Access Journals (Sweden)

Walker Angela M

2009-04-01

Full Text Available Abstract Background The Pregnancy-associated glycoproteins (PAGs belong to a large family of aspartic peptidases expressed exclusively in the placenta of species in the Artiodactyla order. In cattle, the PAG gene family is comprised of at least 22 transcribed genes, as well as some variants. Phylogenetic analyses have shown that the PAG family segregates into 'ancient' and 'modern' groupings. Along with sequence differences between family members, there are clear distinctions in their spatio-temporal distribution and in their relative level of expression. In this report, 1 we performed an in silico analysis of the bovine genome to further characterize the PAG gene family, 2 we scrutinized proximal promoter sequences of the PAG genes to evaluate the evolution pressures operating on them and to identify putative regulatory regions, 3 we determined relative transcript abundance of selected PAGs during pregnancy and, 4 we performed preliminary characterization of the putative regulatory elements for one of the candidate PAGs, bovine (bo PAG-2. Results From our analysis of the bovine genome, we identified 18 distinct PAG genes and 14 pseudogenes. We observed that the first 500 base pairs upstream of the translational start site contained multiple regions that are conserved among all boPAGs. However, a preponderance of conserved regions, that harbor recognition sites for putative transcriptional factors (TFs, were found to be unique to the modern boPAG grouping, but not the ancient boPAGs. We gathered evidence by means of Q-PCR and screening of EST databases to show that boPAG-2 is the most abundant of all boPAG transcripts. Finally, we provided preliminary evidence for the role of ETS- and DDVL-related TFs in the regulation of the boPAG-2 gene. Conclusion PAGs represent a relatively large gene family in the bovine genome. The proximal promoter regions of these genes display differences in putative TF binding sites, likely contributing to observed

Identification of a novel first exon in the human dystrophin gene and of a new promoter located more than 500 kb upstream of the nearest known promoter

Energy Technology Data Exchange (ETDEWEB)

Yanagawa, H.; Nishio, H.; Takeshima, Y. [Kobe Univ. School of Medicine (Japan)] [and others

1994-09-01

The dystrophin gene, which is muted in patients with Duchenne and Becker muscular dystrophies, is the largest known human gene. Five alternative promoters have been characterized until now. Here we show that a novel dystrophin isoform with a different first exon can be produced through transcription initiation at a previously-unidentified alternative promoter. The case study presented is that of patient with Duchenne muscular dystrophy who had a deletion extending from 5{prime} end of the dystrophin gene to exon 2, including all promoters previously mapped in the 5{prime} part of the gene. Transcripts from lymphoblastoid cells were found to contain sequences corresponding to exon 3, indicating the presence of new promoter upstream of this exon. The nucleotide sequence of amplified cDNA corresponding to the 5{prime} end of the new transcript indicated that the 5{prime} end of exon 3 was extended by 9 codons, only the last (most 3{prime}) of which codes for methionine. The genomic nucleotide sequence upstream from the new exon, as determined using inverse polymerase chain reaction, revealed the presence of sequences similar to a TATA box, an octamer motif and an MEF-2 element. The identified promoter/exon did not map to intron 2, as might have been expected, but to a position more than 500 kb upstream of the most 5{prime} of the previously-identified promoters, thereby adding 500 kb to the dystrophin gene. The sequence of part of the new promoter region is very similar to that of certain medium reiteration frequency repetitive sequences. These findings may help us understand the molecular evolution of the dystrophin gene.

Lack of promoter IV-driven BDNF transcription results in depression-like behavior.

Science.gov (United States)

Sakata, K; Jin, L; Jha, S

2010-10-01

Transcription of Bdnf is controlled by multiple promoters, in which promoter IV contributes significantly to activity-dependent Bdnf transcription. We have generated promoter IV mutant mice [brain-derived neurotrophic factor (BDNF)-KIV] in which promoter IV-driven expression of BDNF is selectively disrupted by inserting a green fluorescent protein (GFP)-STOP cassette within the Bdnf exon IV locus. BDNF-KIV animals exhibited depression-like behavior as shown by the tail suspension test (TST), sucrose preference test (SPT) and learned helplessness test (LHT). In addition, BDNF-KIV mice showed reduced activity in the open field test (OFT) and reduced food intake in the novelty-suppressed feeding test (NSFT). The mutant mice did not display anxiety-like behavior in the light and dark box test and elevated plus maze tests. Interestingly, the mutant mice showed defective response inhibition in the passive avoidance test (PAT) even though their learning ability was intact when measured with the active avoidance test (AAT). These results suggest that promoter IV-dependent BDNF expression plays a critical role in the control of mood-related behaviors. This is the first study that directly addressed the effects of endogenous promoter-driven expression of BDNF in depression-like behavior. © 2010 The Authors. Genes, Brain and Behavior © 2010 Blackwell Publishing Ltd and International Behavioural and Neural Genetics Society.

Association of a Human FABP1 Gene Promoter Region Polymorphism with Altered Serum Triglyceride Levels.

Directory of Open Access Journals (Sweden)

Xian-E Peng

Full Text Available Liver fatty acid-binding protein (L-FABP, also known as fatty acid-binding protein 1 (FABP1, is a key regulator of hepatic lipid metabolism. Elevated FABP1 levels are associated with an increased risk of cardiovascular disease (CVD and metabolic syndromes. In this study, we examine the association of FABP1 gene promoter variants with serum FABP1 and lipid levels in a Chinese population. Four promoter single-nucleotide polymorphisms (SNPs of FABP1 gene were genotyped in a cross-sectional survey of healthy volunteers (n = 1,182 from Fuzhou city of China. Results showed that only the rs2919872 G>A variant was significantly associated with serum TG concentration(P = 0.032.Compared with the rs2919872 G allele, rs2919872 A allele contributed significantly to reduced serum TG concentration, and this allele dramatically decreased the FABP1 promoter activity(P < 0.05. The rs2919872 A allele carriers had considerably lower serum FABP1 levels than G allele carriers (P < 0.01. In the multivariable linear regression analysis, the rs2919872 A allele was negatively associated with serum FABP1 levels (β = -0.320, P = 0.003, while serum TG levels were positively associated with serum FABP1 levels (β = 0.487, P = 0.014. Our data suggest that compared with the rs2919872 G allele, the rs2919872 A allele reduces the transcriptional activity of FABP1 promoter, and thereby may link FABP1 gene variation to TG level in humans.

[Molecular pathogenesis of Waardenburg syndrome type II resulting from SOX10 gene mutation].

Science.gov (United States)

Zhang, Hua; Chen, Hongsheng; Feng, Yong; Qian, Minfei; Li, Jiping; Liu, Jun; Zhang, Chun

2016-08-01

To explore the molecular mechanism of Waardenburg syndrome type II (WS2) resulting from SOX10 gene mutation E248fs through in vitro experiment. 293T cells were transiently transfected with wild type (WT) SOX10 and mutant type (MT) E248fs plasmids. The regulatory effect of WT/MT SOX10 on the transcriptional activity of MITF gene and influence of E248fs on WT SOX10 function were determined with a luciferase activity assay. The DNA binding capacity of the WT/MT SOX10 with the promoter of the MITF gene was determined with a biotinylated double-stranded oligonucleotide probe containing the SOX10 binding sequence cattgtc to precipitate MITF and E248fs, respectively. The stability of SOX10 and E248fs were also analyzed. As a loss-of-function mutation, the E248fs mutant failed to transactivate the MITF promoter as compared with the WT SOX10 (P<0.01), which also showed a dominant-negative effect on WT SOX10. The WT SOX10 and E248fs mutant were also able to bind specifically to the cattgtc motif in the MITF promoter, whereas E248fs had degraded faster than WT SOX10. Despite the fact that the E248fs has a dominant-negative effect on SOX10, its reduced stability may down-regulate the transcription of MITF and decrease the synthesis of melanin, which may result in haploinsufficiency of SOX10 protein and cause the milder WS2 phenotype.

The promoter for a variant surface glycoprotein gene expression site in Trypanosoma brucei

NARCIS (Netherlands)

Zomerdijk, J. C.; Ouellette, M.; ten Asbroek, A. L.; Kieft, R.; Bommer, A. M.; Clayton, C. E.; Borst, P.

1990-01-01

The variant-specific surface glycoprotein (VSG) gene 221 of Trypanosoma brucei is transcribed as part of a 60 kb expression site (ES). We have identified the promoter controlling this multigene transcription unit by the use of 221 chromosome-enriched DNA libraries and VSG gene 221 expression site

Cloning and Functional Analysis of the Promoter of an Ascorbate Oxidase Gene from Gossypium hirsutum.

Directory of Open Access Journals (Sweden)

Shan Xin

Full Text Available Apoplastic ascorbate oxidase (AO plays significant roles in plant cell growth. However, the mechanism of underlying the transcriptional regulation of AO in Gossypium hirsutum remains unclear. Here, we obtained a 1,920-bp promoter sequence from the Gossypium hirsutum ascorbate oxidase (GhAO1 gene, and this GhAO1 promoter included a number of known cis-elements. Promoter activity analysis in overexpressing pGhAO1::GFP-GUS tobacco (Nicotiana benthamiana showed that the GhAO1 promoter exhibited high activity, driving strong reporter gene expression in tobacco trichomes, leaves and roots. Promoter 5'-deletion analysis demonstrated that truncated GhAO1 promoters with serial 5'-end deletions had different GUS activities. A 360-bp fragment was sufficient to activate GUS expression. The P-1040 region had less GUS activity than the P-720 region, suggesting that the 320-bp region from nucleotide -720 to -1040 might include a cis-element acting as a silencer. Interestingly, an auxin-responsive cis-acting element (TGA-element was uncovered in the promoter. To analyze the function of the TGA-element, tobacco leaves transformed with promoters with different 5' truncations were treated with indole-3-acetic acid (IAA. Tobacco leaves transformed with the promoter regions containing the TGA-element showed significantly increased GUS activity after IAA treatment, implying that the fragment spanning nucleotides -1760 to -1600 (which includes the TGA-element might be a key component for IAA responsiveness. Analyses of the AO promoter region and AO expression pattern in Gossypium arboreum (Ga, diploid cotton with an AA genome, Gossypium raimondii (Gr, diploid cotton with a DD genome and Gossypium hirsutum (Gh, tetraploid cotton with an AADD genome indicated that AO promoter activation and AO transcription were detected together only in D genome/sub-genome (Gr and Gh cotton. Taken together, these results suggest that the 1,920-bp GhAO1 promoter is a functional sequence

Cloning and Functional Analysis of the Promoter of an Ascorbate Oxidase Gene from Gossypium hirsutum.

Science.gov (United States)

Xin, Shan; Tao, Chengcheng; Li, Hongbin

2016-01-01

Apoplastic ascorbate oxidase (AO) plays significant roles in plant cell growth. However, the mechanism of underlying the transcriptional regulation of AO in Gossypium hirsutum remains unclear. Here, we obtained a 1,920-bp promoter sequence from the Gossypium hirsutum ascorbate oxidase (GhAO1) gene, and this GhAO1 promoter included a number of known cis-elements. Promoter activity analysis in overexpressing pGhAO1::GFP-GUS tobacco (Nicotiana benthamiana) showed that the GhAO1 promoter exhibited high activity, driving strong reporter gene expression in tobacco trichomes, leaves and roots. Promoter 5'-deletion analysis demonstrated that truncated GhAO1 promoters with serial 5'-end deletions had different GUS activities. A 360-bp fragment was sufficient to activate GUS expression. The P-1040 region had less GUS activity than the P-720 region, suggesting that the 320-bp region from nucleotide -720 to -1040 might include a cis-element acting as a silencer. Interestingly, an auxin-responsive cis-acting element (TGA-element) was uncovered in the promoter. To analyze the function of the TGA-element, tobacco leaves transformed with promoters with different 5' truncations were treated with indole-3-acetic acid (IAA). Tobacco leaves transformed with the promoter regions containing the TGA-element showed significantly increased GUS activity after IAA treatment, implying that the fragment spanning nucleotides -1760 to -1600 (which includes the TGA-element) might be a key component for IAA responsiveness. Analyses of the AO promoter region and AO expression pattern in Gossypium arboreum (Ga, diploid cotton with an AA genome), Gossypium raimondii (Gr, diploid cotton with a DD genome) and Gossypium hirsutum (Gh, tetraploid cotton with an AADD genome) indicated that AO promoter activation and AO transcription were detected together only in D genome/sub-genome (Gr and Gh) cotton. Taken together, these results suggest that the 1,920-bp GhAO1 promoter is a functional sequence with a

Genomic organization and identification of promoter regions for the BDNF gene in the pond turtle Trachemys scripta elegans.

Science.gov (United States)

Ambigapathy, Ganesh; Zheng, Zhaoqing; Keifer, Joyce

2014-08-01

Brain-derived neurotrophic factor (BDNF) is an important regulator of neuronal development and synaptic function. The BDNF gene undergoes significant activity-dependent regulation during learning. Here, we identified the BDNF promoter regions, transcription start sites, and potential regulatory sequences for BDNF exons I-III that may contribute to activity-dependent gene and protein expression in the pond turtle Trachemys scripta elegans (tBDNF). By using transfection of BDNF promoter/luciferase plasmid constructs into human neuroblastoma SHSY5Y cells and mouse embryonic fibroblast NIH3T3 cells, we identified the basal regulatory activity of promoter sequences located upstream of each tBDNF exon, designated as pBDNFI-III. Further, through chromatin immunoprecipitation (ChIP) assays, we detected CREB binding directly to exon I and exon III promoters, while BHLHB2, but not CREB, binds within the exon II promoter. Elucidation of the promoter regions and regulatory protein binding sites in the tBDNF gene is essential for understanding the regulatory mechanisms that control tBDNF gene expression.

Comparative analyses of bidirectional promoters in vertebrates

Directory of Open Access Journals (Sweden)

Taylor James

2008-05-01

Full Text Available Abstract Background Orthologous genes with deep phylogenetic histories are likely to retain similar regulatory features. In this report we utilize orthology assignments for pairs of genes co-regulated by bidirectional promoters to map the ancestral history of the promoter regions. Results Our mapping of bidirectional promoters from humans to fish shows that many such promoters emerged after the divergence of chickens and fish. Furthermore, annotations of promoters in deep phylogenies enable detection of missing data or assembly problems present in higher vertebrates. The functional importance of bidirectional promoters is indicated by selective pressure to maintain the arrangement of genes regulated by the promoter over long evolutionary time spans. Characteristics unique to bidirectional promoters are further elucidated using a technique for unsupervised classification, known as ESPERR. Conclusion Results of these analyses will aid in our understanding of the evolution of bidirectional promoters, including whether the regulation of two genes evolved as a consequence of their proximity or if function dictated their co-regulation.

The study on Egr-1 promoter which is radioactive promoter

International Nuclear Information System (INIS)

Zhang Chunzhi; Guo Yang; Lv Zhonghong

2006-01-01

Radiogenetic therapy is a heated reaseach on oncotherapy. Early growth response gene-1 (Egr-1) gene promoter is a probably means in radiogenetic therapy. The article review studying on Egr-1 gene promoter and constructing regulating gene expressing system by radiation-inducible Egr-1 gene promoter. (authors)

Correlation between the methylation of APC gene promoter and colon cancer.

Science.gov (United States)

Li, Bing-Qiang; Liu, Peng-Peng; Zhang, Cai-Hua

2017-08-01

The present study was planned to explore the correlation between the methylation of APC (adenomatous polyposis coli) and colon carcinogenesis. Colon cancer tissues and tumor-adjacent normal tissues of 60 colon cancer patients (who received surgical operation in our hospital from January 2012 to December 2014) were collected. SW1116 cells in human colon cancer tissues were selected for culturing. 5-aza-2c-deoxycytidine (5-aza-dC) was utilized as an inhibitor of the methylation for APC gene. Methylation specific PCR (MSP) was utilized for detection of APC methylation in SW1116 cells. The MTT and Transwell assays were performed to detect the effect of the methylation of APC gene on the proliferation and invasive abilities of SW1116 cells. The correlation between the methylation of APC gene and pathological parameters of colon cancer patients was analyzed. MSP results revealed that 41 cases (68.33%) showed methylation of APC gene in colon cancer tissues. No methylation of APC gene was found in tumor-adjacent normal tissues. 5-aza-dC was able to inhibit the methylation of APC gene in SW1116 cells. APC gene methylation was correlated with tumor size, differentiation degree, lymph node metastasis and Dukes staging. In conclusion, the levels of the methylation of APC in colon cancer tissues and SW1116 cells are relatively high. The methylation of APC promoted the proliferation and invasion abilities of SW1116 cells. Furthermore, methylation is correlated with a variety of clinicopathological features of colon cancer patients.

Cloning and expression of Icc1 Laccase gene promoter in Aspergillus niger

International Nuclear Information System (INIS)

Marqueda-Galvez, A. P.; Loera Carrol, O.; Xaconostle cazares, B.; Tellez-Jurado, A.; Arana-Cuenca, A.

2009-01-01

The white rot fungus Trametes sp. I-62 is a strain with laccase activity and a great potential for biotechnological applications given its ability to detoxify distillery effluents. The Icc1, Icc2 and Icc3 laccase genes of this basidiomycetes have been cloned and sequenced. The promoter region of Icc1 laccase gene contains a putative site for xenobiotics (XRE). (Author)

Cloning and expression of Icc1 Laccase gene promoter in Aspergillus niger

Energy Technology Data Exchange (ETDEWEB)

Marqueda-Galvez, A. P.; Loera Carrol, O.; Xaconostle cazares, B.; Tellez-Jurado, A.; Arana-Cuenca, A.

2009-07-01

The white rot fungus Trametes sp. I-62 is a strain with laccase activity and a great potential for biotechnological applications given its ability to detoxify distillery effluents. The Icc1, Icc2 and Icc3 laccase genes of this basidiomycetes have been cloned and sequenced. The promoter region of Icc1 kaccase gene contains a putative site for xenobiotics (XRE). (Author)

Promoter sequence of 3-phosphoglycerate kinase gene 1 of lactic acid-producing fungus rhizopus oryzae and a method of expressing a gene of interest in fungal species

Energy Technology Data Exchange (ETDEWEB)

Gao, Johnway [Richland, WA; Skeen, Rodney S [Pendleton, OR

2002-10-15

The present invention provides the promoter clone discovery of phosphoglycerate kinase gene 1 of a lactic acid-producing filamentous fungal strain, Rhizopus oryzae. The isolated promoter can constitutively regulate gene expression under various carbohydrate conditions. In addition, the present invention also provides a design of an integration vector for the transformation of a foreign gene in Rhizopus oryzae.

Promoter sequence of 3-phosphoglycerate kinase gene 2 of lactic acid-producing fungus rhizopus oryzae and a method of expressing a gene of interest in fungal species

Energy Technology Data Exchange (ETDEWEB)

Gao, Johnway [Richland, WA; Skeen, Rodney S [Pendleton, OR

2003-03-04

The present invention provides the promoter clone discovery of phosphoglycerate kinase gene 2 of a lactic acid-producing filamentous fungal strain, Rhizopus oryzae. The isolated promoter can constitutively regulate gene expression under various carbohydrate conditions. In addition, the present invention also provides a design of an integration vector for the transformation of a foreign gene in Rhizopus oryzae.

Quantitative global and gene-specific promoter methylation in relation to biological properties of neuroblastomas

Directory of Open Access Journals (Sweden)

Kiss Nimrod B

2012-09-01

Full Text Available Abstract Background In this study we aimed to quantify tumor suppressor gene (TSG promoter methylation densities levels in primary neuroblastoma tumors and cell lines. A subset of these TSGs is associated with a CpG island methylator phenotype (CIMP in other tumor types. Methods The study panel consisted of 38 primary tumors, 7 established cell lines and 4 healthy references. Promoter methylation was determined by bisulphate Pyrosequencing for 14 TSGs; and LINE-1 repeat element methylation was used as an indicator of global methylation levels. Results Overall mean TSG Z-scores were significantly increased in cases with adverse outcome, but were unrelated to global LINE-1 methylation. CIMP with hypermethylation of three or more gene promoters was observed in 6/38 tumors and 7/7 cell lines. Hypermethylation of one or more TSG (comprising TSGs BLU, CASP8, DCR2, CDH1, RASSF1A and RASSF2 was evident in 30/38 tumors. By contrast only very low levels of promoter methylation were recorded for APC, DAPK1, NORE1A, P14, P16, TP73, PTEN and RARB. Similar involvements of methylation instability were revealed between cell line models and neuroblastoma tumors. Separate analysis of two proposed CASP8 regulatory regions revealed frequent and significant involvement of CpG sites between exon 4 and 5, but modest involvement of the exon 1 region. Conclusions/significance The results highlight the involvement of TSG methylation instability in neuroblastoma tumors and cell lines using quantitative methods, support the use of DNA methylation analyses as a prognostic tool for this tumor type, and underscore the relevance of developing demethylating therapies for its treatment.

Promoter activity of polypyrimidine tract-binding protein genes of potato responds to environmental cues.

Science.gov (United States)

Butler, Nathaniel M; Hannapel, David J

2012-12-01

Polypyrimidine tract-binding (PTB) proteins are RNA-binding proteins that target specific RNAs for post-transcriptional processing by binding cytosine/uracil motifs. PTBs have established functions in a range of RNA processes including splicing, translation, stability and long-distance transport. Six PTB-like genes identified in potato have been grouped into two clades based on homology to other known plant PTBs. StPTB1 and StPTB6 are closely related to a PTB protein discovered in pumpkin, designated CmRBP50, and contain four canonical RNA-recognition motifs. CmRBP50 is expressed in phloem tissues and functions as the core protein of a phloem-mobile RNA/protein complex. Sequence from the potato genome database was used to clone the upstream sequence of these two PTB genes and analyzed to identify conserved cis-elements. The promoter of StPTB6 was enriched for regulatory elements for light and sucrose induction and defense. Upstream sequence of both PTB genes was fused to β-glucuronidase and monitored in transgenic potato lines. In whole plants, the StPTB1 promoter was most active in leaf veins and petioles, whereas StPTB6 was most active in leaf mesophyll. Both genes are active in new tubers and tuber sprouts. StPTB6 expression was induced in stems and stolon sections in response to sucrose and in leaves or petioles in response to light, heat, drought and mechanical wounding. These results show that CmRBP50-like genes of potato exhibit distinct expression patterns and respond to both developmental and environmental cues.

Zinc sulfate contributes to promote telomere length extension via increasing telomerase gene expression, telomerase activity and change in the TERT gene promoter CpG island methylation status of human adipose-derived mesenchymal stem cells.

Directory of Open Access Journals (Sweden)

Raheleh Farahzadi

Full Text Available The use of mesenchymal stem cells (MSCs for cell therapy and regenerative medicine has received widespread attention over the past few years, but their application can be complicated by factors such as reduction in proliferation potential, the senescent tendency of the MSCs upon expansion and their age-dependent decline in number and function. It was shown that all the mentioned features were accompanied by a reduction in telomerase activity and telomere shortening. Furthermore, the role of epigenetic changes in aging, especially changes in promoter methylation, was reported. In this study, MSCs were isolated from the adipose tissue with enzymatic digestion. In addition, immunocytochemistry staining and flow cytometric analysis were performed to investigate the cell-surface markers. In addition, alizarin red-S, sudan III, toluidine blue, and cresyl violet staining were performed to evaluate the multi-lineage differentiation of hADSCs. In order to improve the effective application of MSCs, these cells were treated with 1.5 × 10-8 and 2.99 × 10-10 M of ZnSO4 for 48 hours. The length of the absolute telomere, human telomerase reverse transcriptase (hTERT gene expression, telomerase activity, the investigation of methylation status of the hTERT gene promoter and the percentage of senescent cells were analyzed with quantitative real-time PCR, PCR-ELISA TRAP assay, methylation specific PCR (MSP, and beta-galactosidase (SA-β-gal staining, respectively. The results showed that the telomere length, the hTERT gene expression, and the telomerase activity had significantly increased. In addition, the percentage of senescent cells had significantly decreased and changes in the methylation status of the CpG islands in the hTERT promoter region under treatment with ZnSO4 were seen. In conclusion, it seems that ZnSO4 as a proper antioxidant could improve the aging-related features due to lengthening of the telomeres, increasing the telomerase gene expression

Evolutionary acquisition of promoter-associated non-coding RNA (pancRNA) repertoires diversifies species-dependent gene activation mechanisms in mammals

OpenAIRE

Uesaka, Masahiro; Agata, Kiyokazu; Oishi, Takao; Nakashima, Kinichi; Imamura, Takuya

2017-01-01

Background Recent transcriptome analyses have shown that long non-coding RNAs (ncRNAs) play extensive roles in transcriptional regulation. In particular, we have reported that promoter-associated ncRNAs (pancRNAs) activate the partner gene expression via local epigenetic changes. Results Here, we identify thousands of genes under pancRNA-mediated transcriptional activation in five mammalian species in common. In the mouse, 1) pancRNA-partnered genes confined their expression pattern to certai...

The artificial zinc finger coding gene 'Jazz' binds the utrophin promoter and activates transcription.

Science.gov (United States)

Corbi, N; Libri, V; Fanciulli, M; Tinsley, J M; Davies, K E; Passananti, C

2000-06-01

Up-regulation of utrophin gene expression is recognized as a plausible therapeutic approach in the treatment of Duchenne muscular dystrophy (DMD). We have designed and engineered new zinc finger-based transcription factors capable of binding and activating transcription from the promoter of the dystrophin-related gene, utrophin. Using the recognition 'code' that proposes specific rules between zinc finger primary structure and potential DNA binding sites, we engineered a new gene named 'Jazz' that encodes for a three-zinc finger peptide. Jazz belongs to the Cys2-His2 zinc finger type and was engineered to target the nine base pair DNA sequence: 5'-GCT-GCT-GCG-3', present in the promoter region of both the human and mouse utrophin gene. The entire zinc finger alpha-helix region, containing the amino acid positions that are crucial for DNA binding, was specifically chosen on the basis of the contacts more frequently represented in the available list of the 'code'. Here we demonstrate that Jazz protein binds specifically to the double-stranded DNA target, with a dissociation constant of about 32 nM. Band shift and super-shift experiments confirmed the high affinity and specificity of Jazz protein for its DNA target. Moreover, we show that chimeric proteins, named Gal4-Jazz and Sp1-Jazz, are able to drive the transcription of a test gene from the human utrophin promoter.

Association of the Resistin Gene Promoter Region Polymorphism with Kawasaki Disease in Chinese Children

Directory of Open Access Journals (Sweden)

Ruixi Liu

2012-01-01

Full Text Available Objectives. The −420C>G polymorphism located in the resistin gene (RETN promoter has recently been suggested to play a potential role in proinflammatory conditions and cardiovascular disease. This study investigated the association of the RETN promoter polymorphism with Kawasaki disease (KD and its clinical parameters in Chinese children. Methods. We compared patients with complete KD to incomplete KD children. Genotyping of the RETN promoter polymorphism was performed using MassARRAY system, and serum resistin levels were estimated using the sandwich enzyme immunoassay method. Results. There was no significant difference in RETN (−420C>G genotypes between KD and control groups. However, the frequency of the G allele was higher in iKD patients than in cKD children due to a significantly increased frequency of the GG genotypes. Serum levels of resistin were significantly higher in KD patients than in controls regardless of the presence of coronary artery lesions (CALs. Conclusion. The present findings suggest that while resistin may play a role in the pathogenesis of KD, there is no apparent association between CAL and the RETN (−420C>G gene polymorphism in KD children. However, the diagnosis of iKD is challenging but can be supported by the presence of the G allele and the GG genotypes.

Quantitative promoter methylation analysis of multiple cancer-related genes in renal cell tumors

International Nuclear Information System (INIS)

Costa, Vera L; Henrique, Rui; Ribeiro, Franclim R; Pinto, Mafalda; Oliveira, Jorge; Lobo, Francisco; Teixeira, Manuel R; Jerónimo, Carmen

2007-01-01

Aberrant promoter hypermethylation of cancer-associated genes occurs frequently during carcinogenesis and may serve as a cancer biomarker. In this study we aimed at defining a quantitative gene promoter methylation panel that might identify the most prevalent types of renal cell tumors. A panel of 18 gene promoters was assessed by quantitative methylation-specific PCR (QMSP) in 85 primarily resected renal tumors representing the four major histologic subtypes (52 clear cell (ccRCC), 13 papillary (pRCC), 10 chromophobe (chRCC), and 10 oncocytomas) and 62 paired normal tissue samples. After genomic DNA isolation and sodium bisulfite modification, methylation levels were determined and correlated with standard clinicopathological parameters. Significant differences in methylation levels among the four subtypes of renal tumors were found for CDH1 (p = 0.0007), PTGS2 (p = 0.002), and RASSF1A (p = 0.0001). CDH1 hypermethylation levels were significantly higher in ccRCC compared to chRCC and oncocytoma (p = 0.00016 and p = 0.0034, respectively), whereas PTGS2 methylation levels were significantly higher in ccRCC compared to pRCC (p = 0.004). RASSF1A methylation levels were significantly higher in pRCC than in normal tissue (p = 0.035). In pRCC, CDH1 and RASSF1A methylation levels were inversely correlated with tumor stage (p = 0.031) and nuclear grade (p = 0.022), respectively. The major subtypes of renal epithelial neoplasms display differential aberrant CDH1, PTGS2, and RASSF1A promoter methylation levels. This gene panel might contribute to a more accurate discrimination among common renal tumors, improving preoperative assessment and therapeutic decision-making in patients harboring suspicious renal masses

Characterization of promoter of EgPAL1, a novel PAL gene from the oil palm Elaeis guineensis Jacq.

Science.gov (United States)

Yusuf, Chong Yu Lok; Abdullah, Janna Ong; Shaharuddin, Noor Azmi; Abu Seman, Idris; Abdullah, Mohd Puad

2018-02-01

The oil palm EgPAL1 gene promoter and its regulatory region were functional as a promoter in the heterologous system of Arabidopsis according to the cis-acting elements present in that region. The promoter was developmentally regulated, vascular tissue specific and responsive to water stress agents. Phenylalanine ammonia lyase (PAL, EC 4.3.1.24) is the key enzyme of the phenylpropanoid pathway which plays important roles in plant development and adaptation. To date, there is no report on the study of PAL from oil palm (Elaeis guineensis), an economically important oil crop. In this study, the 5' regulatory sequence of a highly divergent oil palm PAL gene (EgPAL1) was isolated and fused with GUS in Arabidopsis to create two transgenic plants carrying the minimal promoter with (2302 bp) and without its regulatory elements (139 bp). The regulatory sequence contained cis-acting elements known to be important for plant development and stress response including the AC-II element for lignin biosynthesis and several stress responsive elements. The promoter and its regulatory region were fully functional in Arabidopsis. Its activities were characterised by two common fundamental features of PAL which are responsive to plant internal developmental programme and external factors. The promoter was developmentally regulated in certain organs; highly active in young organs but less active or inactive in mature organs. The presence of the AC elements and global activity of the EgPAL1 promoter in all organs resembled the property of lignin-related genes. The existence of the MBS element and enhancement of the promoter activity by PEG reflected the behaviour of drought-responsive genes. Our findings provide a platform for evaluating oil palm gene promoters in the heterologous system of Arabidopsis and give insights into the activities of EgPAL1 promoter in oil palm.

DNMT 1 maintains hypermethylation of CAG promoter specific region and prevents expression of exogenous gene in fat-1 transgenic sheep.

Science.gov (United States)

Yang, Chunrong; Shang, Xueying; Cheng, Lei; Yang, Lei; Liu, Xuefei; Bai, Chunling; Wei, Zhuying; Hua, Jinlian; Li, Guangpeng

2017-01-01

Methylation is an important issue in gene expression regulation and also in the fields of genetics and reproduction. In this study, we created fat-1 transgenic sheep, investigated the fine-mapping and the modulatory mechanisms of promoter methylation. Sheep fetal fibroblasts were transfected by pCAG-fat1-IRES-EGFP. Monoclonal cell line was screened as nuclear donor and carried out nuclear transfer (441 transgenic cloned embryos, 52 synchronism recipient sheep). Six offsprings were obtained. Expressions of exogenous genes fat-1 and EGFP were detectable in 10 examined tissues and upregulated omega-3 fatty acid content. Interestingly, more or less EGFP negative cells were detectable in the positive transgenic fetal skin cells. EGFP negative and positive cells were sorted by flow cytometry, and their methylation status in the whole promoter region (1701 nt) were investigated by bisulphate sequencing. The fine-mapping of methylation in CAG promoter were proposed. The results suggested that exogenous gene expression was determined by the methylation status from 721-1346 nt and modulated by methylation levels at 101, 108 and 115 nt sites in CAG promoter. To clarify the regulatory mechanism of methylation, examination of four DNA methyltransferases (DNMTs) demonstrated that hypermethylation of CAG promoter is mainly maintained by DNMT 1 in EGFP negative cells. Furthermore, investigation of the cell surface antigen CD34, CD45 and CD166 indicated that EGFP positive and negative cells belong to different types. The present study systematically clarified methylation status of CAG promoter in transgenic sheep and regulatory mechanism, which will provide research strategies for gene expression regulation in transgenic animals.

DNA methylation of PTEN gene promoter region is not correlated ...

African Journals Online (AJOL)

Tumor suppressor gene PTEN plays an important role in cell cycle. Disorder of PTEN protein can cause cell growth and division in an uncontrolled way, which can lead to the formation of tumors. It has been proven that epigenetic mechanisms, such as promoter hypermethylation, may account for inactivation of PTEN in a ...

Interleukin 10 gene promoter polymorphism and risk of diffuse large ...

African Journals Online (AJOL)

Purpose: Given the importance of understanding the genetic variations involved in the pathogenesis of non-Hodgkin's lymphoma (NHL), this work was designed to study the impact of IL-10 (1082 G/A; rs1800896 and 819 C/T; rs1800871) gene promoter polymorphism on susceptibility of Egyptians to diffuse large B cell ...

Analysis of the Epstein-Barr virus (EBV) latent membrane protein 1 (LMP-1) gene and promoter in Hodgkin's disease isolates

DEFF Research Database (Denmark)

Sandvej, K; Andresen, B S; Zhou, X G

2000-01-01

AIMS: To study the distribution of Epstein-Barr virus (EBV) variants containing mutations in the latent membrane protein 1 (LMP-1) oncogene and promoter in EBV associated Hodgkin's disease and infectious mononucleosis compared with previous findings in asymptomatic EBV carriers. METHODS: Sequence...... analysis of the EBV LMP-1 promoter and gene in isolates from Danish patients with Hodgkin's disease (n = 61) and infectious mononucleosis (n = 10). RESULTS: Viruses (previously designated group D) that contain two mutations in the activating transcription factor/cAMP response element (ATF/CRE) in the LMP-1...... promoter, which are known to decrease promoter activity greatly, were significantly less frequent in Hodgkin's disease than in both infectious mononucleosis (p = 0.0081) and asymptomatic EBV carriers (p = 0.0084). In some cases, the LMP-1 gene contained mutations in a recently identified cytotoxic T cell...

Cloning and functional analysis of the promoters that upregulate carotenogenic gene expression during flower development in Gentiana lutea.

Science.gov (United States)

Zhu, Changfu; Yang, Qingjie; Ni, Xiuzhen; Bai, Chao; Sheng, Yanmin; Shi, Lianxuan; Capell, Teresa; Sandmann, Gerhard; Christou, Paul

2014-04-01

Over the last two decades, many carotenogenic genes have been cloned and used to generate metabolically engineered plants producing higher levels of carotenoids. However, comparatively little is known about the regulation of endogenous carotenogenic genes in higher plants, and this restricts our ability to predict how engineered plants will perform in terms of carotenoid content and composition. During petal development in the Great Yellow Gentian (Gentiana lutea), carotenoid accumulation, the formation of chromoplasts and the upregulation of several carotenogenic genes are temporally coordinated. We investigated the regulatory mechanisms responsible for this coordinated expression by isolating five G. lutea carotenogenic gene (GlPDS, GlZDS, GlLYCB, GlBCH and GlLYCE) promoters by inverse polymerase chain reaction (PCR). Each promoter was sufficient for developmentally regulated expression of the gusA reporter gene following transient expression in tomato (Solanum lycopersicum cv. Micro-Tom). Interestingly, the GlLYCB and GlBCH promoters drove high levels of gusA expression in chromoplast-containing mature green fruits, but low levels in chloroplast-containing immature green fruits, indicating a strict correlation between promoter activity, tomato fruit development and chromoplast differentiation. As well as core promoter elements such as TATA and CAAT boxes, all five promoters together with previously characterized GlZEP promoter contained three common cis-regulatory motifs involved in the response to methyl jasmonate (CGTCA) and ethylene (ATCTA), and required for endosperm expression (Skn-1_motif, GTCAT). These shared common cis-acting elements may represent binding sites for transcription factors responsible for co-regulation. Our data provide insight into the regulatory basis of the coordinated upregulation of carotenogenic gene expression during flower development in G. lutea. © 2013 Scandinavian Plant Physiology Society.

Analysis of tomato gene promoters activated in syncytia induced in tomato and potato hairy roots by Globodera rostochiensis.

Science.gov (United States)

Wiśniewska, A; Dąbrowska-Bronk, J; Szafrański, K; Fudali, S; Święcicka, M; Czarny, M; Wilkowska, A; Morgiewicz, K; Matusiak, J; Sobczak, M; Filipecki, M

2013-06-01

The potato cyst nematode (Globodera rostochiensis) induces feeding sites (syncytia) in tomato and potato roots. In a previous study, 135 tomato genes up-regulated during G. rostochiensis migration and syncytium development were identified. Five genes (CYP97A29, DFR, FLS, NIK and PMEI) were chosen for further study to examine their roles in plant-nematode interactions. The promoters of these genes were isolated and potential cis regulatory elements in their sequences were characterized using bioinformatics tools. Promoter fusions with the β-glucuronidase gene were constructed and introduced into tomato and potato genomes via transformation with Agrobacterium rhizogenes to produce hairy roots. The analysed promoters displayed different activity patterns in nematode-infected and uninfected transgenic hairy roots.

Generation and evaluation of an IPTG-regulated version of Vav-gene promoter for mouse transgenesis.

Directory of Open Access Journals (Sweden)

Francesca Grespi

2011-03-01

Full Text Available Different bacteria-derived systems for regulatable gene expression have been developed for the use in mammalian cells and some were also successfully adopted for in vivo use in vertebrate model organisms. However, certain limitations apply to most of these systems, including leakiness of transgene expression, inefficient transgene silencing or activation, as well as limited tissue accessibility of transgene-inducers or their unfavourable pharmacokinetics. In this study, we evaluated the suitability of the lac-operon/lac-repressor (lacO/lacI system for the regulation of the well-established Vav-gene promoter that allows inducible transgene expression in different haematopoietic lineages in mice. Using the fluorescence marker protein Venus as a reporter, we observed that the lacO/lacI system could be amended to modulate transgene-expression in haematopoietic cells. However, reporter expression was not uniform and the lacO elements introduced into the Vav-gene promoter only conferred limited repression and reversion of lacI-mediated gene silencing after administration of IPTG. Although further optimization of the system is required, the lacO-modified version of the Vav-gene promoter may be adopted as a tool where low basal gene-expression and limited transient induction of protein expression are desired, e.g. for the activation of oncogenes or transgenes that act in a dominant-negative manner.

MGMT, GATA6, CD81, DR4, and CASP8 gene promoter methylation in glioblastoma

Directory of Open Access Journals (Sweden)

Skiriute Daina

2012-06-01

Full Text Available Abstract Background Methylation of promoter region is the major mechanism affecting gene expression in tumors. Recent methylome studies of brain tumors revealed a list of new epigenetically modified genes. Our aim was to study promoter methylation of newly identified epigenetically silenced genes together with already known epigenetic markers and evaluate its separate and concomitant role in glioblastoma genesis and patient outcome. Methods The methylation status of MGMT, CD81, GATA6, DR4, and CASP8 in 76 patients with primary glioblastomas was investigated. Methylation-specific PCR reaction was performed using bisulfite treated DNA. Evaluating glioblastoma patient survival time after operation, patient data and gene methylation effect on survival was estimated using survival analysis. Results The overwhelming majority (97.3% of tumors were methylated in at least one of five genes tested. In glioblastoma specimens gene methylation was observed as follows: MGMT in 51.3%, GATA6 in 68.4%, CD81 in 46.1%, DR4 in 41.3% and CASP8 in 56.8% of tumors. Methylation of MGMT was associated with younger patient age (p CASP8 with older (p MGMT methylation was significantly more frequent event in patient group who survived longer than 36 months after operation (p CASP8 was more frequent in patients who survived shorter than 36 months (p MGMT, GATA6 and CASP8 as independent predictors for glioblastoma patient outcome (p MGMT and GATA6 were independent predictors for patient survival in younger patients’ group, while there were no significant associations observed in older patients’ group when adjusted for therapy. Conclusions High methylation frequency of tested genes shows heterogeneity of glioblastoma epigenome and the importance of MGMT, GATA6 and CASP8 genes methylation in glioblastoma patient outcome.

Identification of an ovine atadenovirus gene whose product activates the viral E2 promoter: possible involvement of E2F-1

International Nuclear Information System (INIS)

Kuemin, Daniel; Hofmann, Christian; Uckert, Wolfgang; Both, Gerald W.; Loeser, Peter

2004-01-01

Activation of the adenoviral E2 promoter is an early step in adenovirus gene expression. For members of the mast- and aviadenoviruses, this requires induction of the cellular transcription factor E2F by virally encoded gene products such as E1A, E4orf6/7 and orf22/GAM-1. The newly recognized genus atadenovirus, of which the ovine isolate OAdV is the prototype, lacks any sequence homology to those genes. To find a possible link between E2 promoter activation and OAdV gene expression, we utilized a screening method to search for genes within the OAdV genome that were capable of stimulating the viral E2 promoter. One such gene, E43, was identified within the proposed E4 region toward the right-hand end of the OAdV genome. The E43 gene product was also found to be capable of stimulating E2F-1-dependent gene expression. A closer inspection of the E2 promoter revealed the presence of a non-palindromic E2F binding site within the OAdV E2 promoter. Mutation of this site markedly reduced both E2F-1- and E43-dependent promoter activation. Moreover, a direct protein-protein interaction of the E43 gene product with E2F, but not with the retinoblastoma protein pRb, suggested a possible cooperation between these two proteins in activating the E2 promoter. The importance of the E43 gene product for virus replication is also underlined by the finding that an OAdV recombinant with a functionally inactivated E43 gene showed severely inhibited virus growth

Over-expression of Gene FaASR Promotes Strawberry Fruit Coloring

Directory of Open Access Journals (Sweden)

Liu Zhongjie

2015-11-01

Full Text Available Fruit development and ripening is a complicate process. Although much progress has been made on the ripenig process, the molecular mechamism of fruit development is not yet clear. In this study, we used ‘Sweet Charlie’ strawberry as test materials, based on cloning the strawberries ASR homologous gene, we carried out the bioinformatics and temporal expression analysis of FaASR, by manipulating ASR gene expression level in strawberry fruit, we tested the changes of physiological indicators, including sugar, ABA, pigments content, and fruit firmness, as well as phenotypic changes. In addition, we measured the expression changes of some anthocyanin-related gene, such as CHS and UFGT, by which we revealed the regulation mechanisms of ASR gene over strawberry fruit ripening. Strawberry ASR contained a typical domain of ABA/WDS that was related to fruit ripening and stress-resistance, and ASR gene over-expression could promote strawberry fruit coloring, endogenous ABA and sucrose accumulation, fruit softening, and induced the transcription levels of anthocyanin-related genes CHS and UFGT. The present study will further reveal the molecular mechanisms of information transmission in fruit development, and will also play an important foundation for future molecular improvement of strawberries breeding.

Gain of DNA methylation is enhanced in the absence of CTCF at the human retinoblastoma gene promoter

International Nuclear Information System (INIS)

Dávalos-Salas, Mercedes; Furlan-Magaril, Mayra; González-Buendía, Edgar; Valdes-Quezada, Christian; Ayala-Ortega, Erandi; Recillas-Targa, Félix

2011-01-01

Long-term gene silencing throughout cell division is generally achieved by DNA methylation and other epigenetic processes. Aberrant DNA methylation is now widely recognized to be associated with cancer and other human diseases. Here we addressed the contribution of the multifunctional nuclear factor CTCF to the epigenetic regulation of the human retinoblastoma (Rb) gene promoter in different tumoral cell lines. To assess the DNA methylation status of the Rb promoter, genomic DNA from stably transfected human erythroleukemic K562 cells expressing a GFP reporter transgene was transformed with sodium bisulfite, and then PCR-amplified with modified primers and sequenced. Single- and multi-copy integrants with the CTCF binding site mutated were isolated and characterized by Southern blotting. Silenced transgenes were reactivated using 5-aza-2'-deoxycytidine and Trichostatin-A, and their expression was monitored by fluorescent cytometry. Rb gene expression and protein abundance were assessed by RT-PCR and Western blotting in three different glioma cell lines, and DNA methylation of the promoter region was determined by sodium bisulfite sequencing, together with CTCF dissociation and methyl-CpG-binding protein incorporation by chromatin immunoprecipitation assays. We found that the inability of CTCF to bind to the Rb promoter causes a dramatic loss of gene expression and a progressive gain of DNA methylation. This study indicates that CTCF plays an important role in maintaining the Rb promoter in an optimal chromatin configuration. The absence of CTCF induces a rapid epigenetic silencing through a progressive gain of DNA methylation. Consequently, CTCF can now be seen as one of the epigenetic components that allows the proper configuration of tumor suppressor gene promoters. Its aberrant dissociation can then predispose key genes in cancer cells to acquire DNA methylation and epigenetic silencing

Functional analysis of a novel human serotonin transporter gene promoter in immortalized raphe cells

DEFF Research Database (Denmark)

Mortensen, O V; Thomassen, M; Larsen, M B

1999-01-01

were found to possess the additional 379 bp fragment. The integrity of the promoter was furthermore confirmed by genomic Southern blotting. The promoter activity was analyzed by reporter gene assays in neuronal and non-neuronal serotonergic cell lines. In immortalized serotonergic raphe neurons, RN46A...

No evidence for promoter region methylation of the succinate dehydrogenase and fumarate hydratase tumour suppressor genes in breast cancer

Directory of Open Access Journals (Sweden)

Dobrovic Alexander

2009-09-01

Full Text Available Abstract Background Succinate dehydrogenase (SDH and fumarate hydratase (FH are tricarboxylic acid (TCA cycle enzymes that are also known to act as tumour suppressor genes. Increased succinate or fumarate levels as a consequence of SDH and FH deficiency inhibit hypoxia inducible factor-1α (HIF-1α prolyl hydroxylases leading to sustained HIF-1α expression in tumours. Since HIF-1α is frequently expressed in breast carcinomas, DNA methylation at the promoter regions of the SDHA, SDHB, SDHC and SDHD and FH genes was evaluated as a possible mechanism in silencing of SDH and FH expression in breast carcinomas. Findings No DNA methylation was identified in the promoter regions of the SDHA, SDHB, SDHC, SDHD and FH genes in 72 breast carcinomas and 10 breast cancer cell lines using methylation-sensitive high resolution melting which detects both homogeneous and heterogeneous methylation. Conclusion These results show that inactivation via DNA methylation of the promoter CpG islands of SDH and FH is unlikely to play a major role in sporadic breast carcinomas.

Polymorphism in promoter of SIX4 gene shows association with its transcription and body measurement traits in Qinchuan cattle.

Science.gov (United States)

Wei, Dawei; Raza, Sayed Haidar Abbas; Zhang, Jiupan; Gui, Linsheng; Rahman, Siddiq Ur; Khan, Rajwali; Hosseini, Seyed Mahdi; Kaleri, Hubdar Ali; Zan, Linsen

2018-05-20

The sine oculis homeobox homolog 4 (SIX4) gene belongs to the SIX gene family, which plays a critical role in muscle regeneration and early stages of ontogeny. This study aimed to detect promoter variations of bovine SIX4 genes in Qinchuan cattle, and to evaluate the effect of transcription regulations and body measurement traits. Quantitative real-time PCR (qPCR) results showed that the mRNA expression levels of SIX4 gene were found significantly highest in longissimus thoracis tissue and individual before attaining the stage of physiological maturity. Using sequencing technology on a total of 428 Qinchuan cattle, seven single nucleotide polymorphisms (SNPs) were identified in the promoter region of SIX4, and seven haplotypes representing 18 potential transcription factor compositions of polymorphic potential cis-acting elements. Association analysis indicated that the H 3 -H 3 diplotype performed greater withers height, chest depth, chest circumference, back fat thickness and ultrasound loin muscle area (P cattle. Copyright © 2018 Elsevier B.V. All rights reserved.

Overexpression and cosuppression of xylem-related genes in an early xylem differentiation stage-specific manner by the AtTED4 promoter.

Science.gov (United States)

Endo, Satoshi; Iwamoto, Kuninori; Fukuda, Hiroo

2018-02-01

Tissue-specific overexpression of useful genes, which we can design according to their cause-and-effect relationships, often gives valuable gain-of-function phenotypes. To develop genetic tools in woody biomass engineering, we produced a collection of Arabidopsis lines that possess chimeric genes of a promoter of an early xylem differentiation stage-specific gene, Arabidopsis Tracheary Element Differentiation-related 4 (AtTED4) and late xylem development-associated genes, many of which are uncharacterized. The AtTED4 promoter directed the expected expression of transgenes in developing vascular tissues from young to mature stage. Of T2 lines examined, 42%, 49% and 9% were judged as lines with the nonrepeat type insertion, the simple repeat type insertion and the other repeat type insertion of transgenes. In 174 T3 lines, overexpression lines were confirmed for 37 genes, whereas only cosuppression lines were produced for eight genes. The AtTED4 promoter activity was high enough to overexpress a wide range of genes over wild-type expression levels, even though the wild-type expression is much higher than AtTED4 expression for several genes. As a typical example, we investigated phenotypes of pAtTED4::At5g60490 plants, in which both overexpression and cosuppression lines were included. Overexpression but not cosuppression lines showed accelerated xylem development, suggesting the positive role of At5g60490 in xylem development. Taken together, this study provides valuable results about behaviours of various genes expressed under an early xylem-specific promoter and about usefulness of their lines as genetic tools in woody biomass engineering. © 2017 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

Regulatory polymorphisms in the bovine Ankyrin 1 gene promoter are associated with tenderness and intramuscular fat content

Directory of Open Access Journals (Sweden)

Sweeney Torres

2010-12-01

Full Text Available Abstract Background Recent QTL and gene expression studies have highlighted ankyrins as positional and functional candidate genes for meat quality. Our objective was to characterise the promoter region of the bovine ankyrin 1 gene and to test polymorphisms for association with sensory and technological meat quality measures. Results Seven novel promoter SNPs were identified in a 1.11 kb region of the ankyrin 1 promoter in Angus, Charolais and Limousin bulls (n = 15 per breed as well as 141 crossbred beef animals for which meat quality data was available. Eighteen haplotypes were inferred with significant breed variation in haplotype frequencies. The five most frequent SNPs and the four most frequent haplotypes were subsequently tested for association with sensory and technological measures of meat quality in the crossbred population. SNP1, SNP3 and SNP4 (which were subsequently designated regulatory SNPs and SNP5 were associated with traits that contribute to sensorial and technological measurements of tenderness and texture; Haplotype 1 and haplotype 4 were oppositely correlated with traits contributing to tenderness (P Conclusion The conclusion from this study is that alleles defining haplotypes 2 and 4 could usefully contribute to marker SNP panels used to select individuals with improved IMF/juiciness or tenderness in a genome-assisted selection framework.

Structural and functional analysis of mouse Msx1 gene promoter: sequence conservation with human MSX1 promoter points at potential regulatory elements.

Science.gov (United States)

Gonzalez, S M; Ferland, L H; Robert, B; Abdelhay, E

1998-06-01

Vertebrate Msx genes are related to one of the most divergent homeobox genes of Drosophila, the muscle segment homeobox (msh) gene, and are expressed in a well-defined pattern at sites of tissue interactions. This pattern of expression is conserved in vertebrates as diverse as quail, zebrafish, and mouse in a range of sites including neural crest, appendages, and craniofacial structures. In the present work, we performed structural and functional analyses in order to identify potential cis-acting elements that may be regulating Msx1 gene expression. To this end, a 4.9-kb segment of the 5'-flanking region was sequenced and analyzed for transcription-factor binding sites. Four regions showing a high concentration of these sites were identified. Transfection assays with fragments of regulatory sequences driving the expression of the bacterial lacZ reporter gene showed that a region of 4 kb upstream of the transcription start site contains positive and negative elements responsible for controlling gene expression. Interestingly, a fragment of 130 bp seems to contain the minimal elements necessary for gene expression, as its removal completely abolishes gene expression in cultured cells. These results are reinforced by comparison of this region with the human Msx1 gene promoter, which shows extensive conservation, including many consensus binding sites, suggesting a regulatory role for them.

Lack of death receptor 4 (DR4) expression through gene promoter methylation in gastric carcinoma.

Science.gov (United States)

Lee, Kyung Hwa; Lim, Sang Woo; Kim, Ho Gun; Kim, Dong Yi; Ryu, Seong Yeob; Joo, Jae Kyun; Kim, Jung Chul; Lee, Jae Hyuk

2009-07-01

To determine the underlying mechanism for the differential expression, the extent of promoter methylation in tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-related genes acting downstream of TRAIL was examined in early and advanced gastric carcinomas. The extent of promoter methylation in the DR4, DR5, DcR1, DcR2, and CASP8 genes was quantified using bisulfite modification and methylation-specific polymerase chain reaction. The promoters for DcR1, DcR2, and CASP8 were largely unmethylated in early gastric carcinoma, advanced gastric carcinoma, and controls, with no significant difference among them. Protein levels of DR4, DcR1, and DcR2 as revealed by immunohistochemistry correlated with the extent of the respective promoter methylation (P < 0.05 in all cases). Hypomethylation, rather than hypermethylation, of the DR4 promoter was noted in invasive gastric malignancies, with statistical significance (P = 0.003). The promoter methylation status of TRAIL receptors in gastric carcinoma may have clinical implications for improving therapeutic strategies in patients with gastric carcinoma.

A var gene promoter implicated in severe malaria nucleates silencing and is regulated by 3' untranslated region and intronic cis-elements.

Science.gov (United States)

Muhle, Rebecca A; Adjalley, Sophie; Falkard, Brie; Nkrumah, Louis J; Muhle, Michael E; Fidock, David A

2009-11-01

Questions surround the mechanism of mutually exclusive expression by which Plasmodium falciparum mediates activation and silencing of var genes. These encode PfEMP1 proteins, which function as cytoadherent and immunomodulatory molecules at the surface of parasitised erythrocytes. Current evidence suggests that promoter silencing by var introns might play a key role in var gene regulation. To evaluate the impact of cis-acting regulatory regions on var silencing, we generated P. falciparum lines in which luciferase was placed under the control of an UpsA var promoter. By utilising the Bxb1 integrase system, these reporter cassettes were targeted to a genomic region that was not in apposition to var subtelomeric domains. This eliminated possible effects from surrounding telomeric elements and removed the variability inherent in episomal systems. Studies with highly synchronised parasites revealed that the UpsA element possessed minimal activity in comparison with a heterologous (hrp3) promoter. This may result from the integrated UpsA promoter being largely silenced by the neighbouring cg6 promoter. Our analyses also revealed that the DownsA 3' untranslated region further decreased the luciferase activity from both cassettes, whereas the var A intron repressed the UpsA promoter specifically. By applying multivariate analysis over the entire cell cycle, we confirmed the significance of these cis-elements and found the parasite stage to be the major factor regulating UpsA-promoter activity. Additionally, we observed that the UpsA promoter was capable of nucleating reversible silencing that spread to a downstream promoter. We believe these studies are the first to analyse promoter activity of Group A var genes, which have been implicated in severe malaria, and support the model that var introns can further suppress var expression. These data also suggest an important suppressive role for the DownsA terminator. Our findings imply the existence of multiple levels of var

Epigenetics in type 1 diabetes: TNFa gene promoter methylation status in Chilean patients with type 1 diabetes mellitus.

Science.gov (United States)

Arroyo-Jousse, Viviana; Garcia-Diaz, Diego F; Codner, Ethel; Pérez-Bravo, Francisco

2016-12-01

TNF-α is a pro-inflammatory cytokine that is involved in type 1 diabetes (T1D) pathogenesis. The TNFa gene is subject of epigenetic regulation in which folate and homocysteine are important molecules because they participate in the methionine cycle where the most important methyl group donor (S-adenosylmethionine) is formed. We investigated whether TNFa gene promoter methylation status in T1D patients was related to blood folate, homocysteine and TNF-α in a transversal case-control study. We studied T1D patients (n 25, mean=13·7 years) and healthy control subjects (n 25, mean=31·1 years), without T1D and/or other autoimmune diseases or direct family history of these diseases. A blood sample was obtained for determination of serum folate, plasma homocysteine and TNF-α concentrations. Whole blood was used for the extraction of DNA to determine the percentage of methylation by real-time PCR and melting-curve analysis. Results are expressed as means and standard deviations for parametric variables and as median (interquartile range) for non-parametric variables. T1D patients showed a higher TNFa gene promoter methylation (39·2 (sd 19·5) %) when compared with control subjects (25·4 (sd 13·7) %) (P=0·008). TNFa gene promoter methylation was positively associated only with homocysteine levels in T1D patients (r 0·55, P=0·007), but not in control subjects (r -0·122, P=0·872). To our knowledge, this is the first work that reports the methylation status of the TNFa gene promoter and its relationship with homocysteine metabolism in Chilean T1D patients without disease complications.

Identification of a functional element in the promoter of the silkworm (Bombyx mori) fat body-specific gene Bmlp3.

Science.gov (United States)

Xu, Hanfu; Deng, Dangjun; Yuan, Lin; Wang, Yuancheng; Wang, Feng; Xia, Qingyou

2014-08-01

30K proteins are a group of structurally related proteins that play important roles in the life cycle of the silkworm Bombyx mori and are largely synthesized and regulated in a time-dependent manner in the fat body. Little is known about the upstream regulatory elements associated with the genes encoding these proteins. In the present study, the promoter of Bmlp3, a fat body-specific gene encoding a 30K protein family member, was characterized by joining sequences containing the Bmlp3 promoter with various amounts of 5' upstream sequences to a luciferase reporter gene. The results indicated that the sequences from -150 to -250bp and -597 to -675bp upstream of the Bmlp3 transcription start site were necessary for high levels of luciferase activity. Further analysis showed that a 21-bp sequence located between -230 and -250 was specifically recognized by nuclear factors from silkworm fat bodies and BmE cells, and could enhance luciferase reporter-gene expression 2.8-fold in BmE cells. This study provides new insights into the Bmlp3 promoter and contributes to the further clarification of the function and developmental regulation of Bmlp3. Copyright © 2014. Published by Elsevier B.V.

Halophytes: Potential Resources for Salt Stress Tolerance Genes and Promoters.

Science.gov (United States)

Mishra, Avinash; Tanna, Bhakti

2017-01-01

Halophytes have demonstrated their capability to thrive under extremely saline conditions and thus considered as one of the best germplasm for saline agriculture. Salinity is a worldwide problem, and the salt-affected areas are increasing day-by-day because of scanty rainfall, poor irrigation system, salt ingression, water contamination, and other environmental factors. The salinity stress tolerance mechanism is a very complex phenomenon, and some pathways are coordinately linked for imparting salinity tolerance. Though a number of salt responsive genes have been reported from the halophytes, there is always a quest for promising stress-responsive genes that can modulate plant physiology according to the salt stress. Halophytes such as Aeluropus, Mesembryanthemum, Suaeda, Atriplex, Thellungiella, Cakile , and Salicornia serve as a potential candidate for the salt-responsive genes and promoters. Several known genes like antiporters ( NHX, SOS, HKT, VTPase ), ion channels (Cl - , Ca 2+ , aquaporins), antioxidant encoding genes ( APX, CAT, GST, BADH, SOD ) and some novel genes such as USP, SDR1, SRP etc. were isolated from halophytes and explored for developing stress tolerance in the crop plants (glycophytes). It is evidenced that stress triggers salt sensors that lead to the activation of stress tolerance mechanisms which involve multiple signaling proteins, up- or down-regulation of several genes, and finally the distinctive or collective effects of stress-responsive genes. In this review, halophytes are discussed as an excellent platform for salt responsive genes which can be utilized for developing salinity tolerance in crop plants through genetic engineering.

par genes in Mycobacterium bovis and Mycobacterium smegmatis are arranged in an operon transcribed from "SigGC" promoters

Directory of Open Access Journals (Sweden)

Casart Yveth

2008-03-01

Full Text Available Abstract Background The ParA/Soj and ParB/Spo0J proteins, and the cis-acting parS site, participate actively in chromosome segregation and cell cycle progression. Genes homologous to parA and parB, and two putative parS copies, have been identified in the Mycobacterium bovis BCG and Mycobacterium smegmatis chromosomes. As in Mycobacterium tuberculosis, the parA and parB genes in these two non-pathogenic mycobacteria are located near the chromosomal origin of replication. The present work focused on the determination of the transcriptional organisation of the ~6 Kb orf60K-parB region of M. bovis BCG and M. smegmatis by primer extension, transcriptional fusions to the green fluorescence protein (GFP and quantitative RT-PCR. Results The parAB genes were arranged in an operon. However, we also found promoters upstream of each one of these genes. Seven putative promoter sequences were identified in the orf60K-parB region of M. bovis BCG, whilst four were identified in the homologous region of M. smegmatis, one upstream of each open reading frame (ORF. Real-time PCR assays showed that in M. smegmatis, mRNA-parA and mRNA-parB levels decreased between the exponential and stationary phases. In M. bovis BCG, mRNA-parA levels also decreased between the exponential and stationary phases. However, parB expression was higher than parA expression and remained almost unchanged along the growth curve. Conclusion The majority of the proposed promoter regions had features characteristic of Mycobacterium promoters previously denoted as Group D. The -10 hexamer of a strong E. coli σ70-like promoter, located upstream of gidB of M. bovis BCG, overlapped with a putative parS sequence, suggesting that the transcription from this promoter might be regulated by the binding of ParB to parS.

Promoter demethylation of Keap1 gene in human diabetic cataractous lenses

Energy Technology Data Exchange (ETDEWEB)

Palsamy, Periyasamy [Department of Ophthalmology and Visual Sciences, University of Nebraska Medical Center, Omaha, NE (United States); Ayaki, Masahiko [Shizuoka National Hospital, Saitama (Japan); Elanchezhian, Rajan [Department of Ophthalmology and Visual Sciences, University of Nebraska Medical Center, Omaha, NE (United States); Shinohara, Toshimichi, E-mail: tshinohara@unmc.edu [Department of Ophthalmology and Visual Sciences, University of Nebraska Medical Center, Omaha, NE (United States)

2012-07-06

Highlights: Black-Right-Pointing-Pointer We found significant Keap1 promoter demethylation in diabetic cataractous lenses. Black-Right-Pointing-Pointer Demethylation of Keap1 gene upregulated the expression of Keap1 mRNA and protein. Black-Right-Pointing-Pointer Elevated levels of Keap1 are known to decrease the levels of Nrf2. Black-Right-Pointing-Pointer Thereby, the levels of antioxidant enzymes are suppressed by decreased Nrf2 level. -- Abstract: Age-related cataracts (ARCs) are the major cause of visual impairments worldwide, and diabetic adults tend to have an earlier onset of ARCs. Although age is the strongest risk factor for cataracts, little is known how age plays a role in the development of ARCs. It is known that oxidative stress in the lens increases with age and more so in the lenses of diabetics. One of the central adaptive responses against the oxidative stresses is the activation of the nuclear transcriptional factor, NF-E2-related factor 2 (Nrf2), which then activates more than 20 different antioxidative enzymes. Kelch-like ECH associated protein 1 (Keap1) targets and binds to Nrf2 for proteosomal degradation. We hypothesized that hyperglycemia will lead to a dysfunction of the Nrf2-dependent antioxidative protection in the lens of diabetics. We studied the methylation status of the CpG islands in 15 clear and 21 diabetic cataractous lenses. Our results showed significant levels of demethylated DNA in the Keap1 promoter in the cataractous lenses from diabetic patients. In contrast, highly methylated DNA was found in the clear lens and tumorized human lens epithelial cell (HLEC) lines (SRA01/04). HLECs treated with a demethylation agent, 5-aza-2 Prime deoxycytidine (5-Aza), had a 10-fold higher levels of Keap1 mRNA, 3-fold increased levels of Keap1 protein, produced higher levels of ROS, and increased cell death. Our results indicated that demethylation of the CpG islands in the Keap1 promoter will activate the expression of Keap1 protein, which

Promoter demethylation of Keap1 gene in human diabetic cataractous lenses

International Nuclear Information System (INIS)

Palsamy, Periyasamy; Ayaki, Masahiko; Elanchezhian, Rajan; Shinohara, Toshimichi

2012-01-01

Highlights: ► We found significant Keap1 promoter demethylation in diabetic cataractous lenses. ► Demethylation of Keap1 gene upregulated the expression of Keap1 mRNA and protein. ► Elevated levels of Keap1 are known to decrease the levels of Nrf2. ► Thereby, the levels of antioxidant enzymes are suppressed by decreased Nrf2 level. -- Abstract: Age-related cataracts (ARCs) are the major cause of visual impairments worldwide, and diabetic adults tend to have an earlier onset of ARCs. Although age is the strongest risk factor for cataracts, little is known how age plays a role in the development of ARCs. It is known that oxidative stress in the lens increases with age and more so in the lenses of diabetics. One of the central adaptive responses against the oxidative stresses is the activation of the nuclear transcriptional factor, NF-E2-related factor 2 (Nrf2), which then activates more than 20 different antioxidative enzymes. Kelch-like ECH associated protein 1 (Keap1) targets and binds to Nrf2 for proteosomal degradation. We hypothesized that hyperglycemia will lead to a dysfunction of the Nrf2-dependent antioxidative protection in the lens of diabetics. We studied the methylation status of the CpG islands in 15 clear and 21 diabetic cataractous lenses. Our results showed significant levels of demethylated DNA in the Keap1 promoter in the cataractous lenses from diabetic patients. In contrast, highly methylated DNA was found in the clear lens and tumorized human lens epithelial cell (HLEC) lines (SRA01/04). HLECs treated with a demethylation agent, 5-aza-2′deoxycytidine (5-Aza), had a 10-fold higher levels of Keap1 mRNA, 3-fold increased levels of Keap1 protein, produced higher levels of ROS, and increased cell death. Our results indicated that demethylation of the CpG islands in the Keap1 promoter will activate the expression of Keap1 protein, which then increases the targeting of Nrf2 for proteosomal degradation. Decreased Nrf2 activity represses the

Tissue-specific production of limonene in Camelina sativa with the Arabidopsis promoters of genes BANYULS and FRUITFULL.

Science.gov (United States)

Borghi, Monica; Xie, De-Yu

2016-02-01

Arabidopsis promoters of genes BANYULS and FRUITFULL are transcribed in Camelina. They triggered the transcription of limonene synthase and induced higher limonene production in seeds and fruits than CaMV 35S promoter. Camelina sativa (Camelina) is an oilseed crop of relevance for the production of biofuels and the plant has been target of a recent and intense program of genetic manipulation aimed to increase performance, seed yield and to modify the fatty acid composition of the oil. Here, we have explored the performance of two Arabidopsis thaliana (Arabidopsis) promoters in triggering transgene expression in Camelina. The promoters of two genes BANYULS (AtBAN pro ) and FRUITFULL (AtFUL pro ), which are expressed in seed coat and valves of Arabidopsis, respectively, have been chosen to induce the expression of limonene synthase (LS) from Citrus limon. In addition, the constitutive CaMV 35S promoter was utilized to overexpress LS in Camelina . The results of experiments revealed that AtBAN pro and AtFUL pro are actively transcribed in Camelina where they also retain specificity of expression in seeds and valves as previously observed in Arabidopsis. LS induced by AtBAN pro and AtFUL pro leads to higher limonene production in seeds and fruits than when the CaMV 35S was used to trigger the expression. In conclusion, the results of experiments indicate that AtBAN pro and AtFUL pro can be successfully utilized to induce the expression of the transgenes of interest in seeds and fruits of Camelina.

Expression of P. falciparum var Genes Involves Exchange of the Histone Variant H2A.Z at the Promoter

Science.gov (United States)

Petter, Michaela; Lee, Chin Chin; Byrne, Timothy J.; Boysen, Katja E.; Volz, Jennifer; Ralph, Stuart A.; Cowman, Alan F.; Brown, Graham V.; Duffy, Michael F.

2011-01-01

silenced, but PfH2A.Z remains enriched at the TSS of var genes; in contrast, PfH2A.Z is lost from the TSS of de-repressed var genes in mature Sir2B knock out parasites. This result indicates that PfH2A.Z occupancy at the active var promoter is antagonized by PfSir2A during the intraerythrocytic life cycle. We conclude that PfH2A.Z contributes to the nucleosome architecture at promoters and is regulated dynamically in active var genes. PMID:21379342

A study of the frequency of methylation of gene promoter regions in ...

Indian Academy of Sciences (India)

2013-04-02

Apr 2, 2013 ... colorectal cancer in the Taiwanese population. CHANG-CHIEH WU1 ... hypermethylation of promoter-region CpG islands is an important ... mismatch repair gene MLH1 plays an important role in dele- ..... Asia Pac. J. Clin.

Deletion of P2 promoter of GJB1 gene a cause of Charcot-Marie-Tooth disease.

Science.gov (United States)

Kulshrestha, R; Burton-Jones, S; Antoniadi, T; Rogers, M; Jaunmuktane, Z; Brandner, S; Kiely, N; Manuel, R; Willis, T

2017-08-01

X-linked Charcot-Marie-Tooth disease (CMT) is the second most common cause of CMT, and is usually caused by mutations in the gap junction protein beta 1 (GJB1) gene. This gene has nerve specific P2 promoter that work synergistically with SOX10 and EGR2 genes to initiate transcription. Mutation in this region is known to cause Schwann cell dysfunction. A single large family of X linked peripheral neuropathy was identified in our practice. Next generation sequencing for targeted panel assay identified an upstream exon-splicing deletion identified extending from nucleotide c.-5413 to approximately - c.-49. This matches the sequence of 32 nucleotides at positions c.*218-*249 in the 3'UTR downstream of the GJB1 gene. The deleted fragment included the entire P2 promoter region. The deletion segregated with the disease. To our knowledge a deletion of the P2 promoter alone as a cause of CMT has not been reported previously. Copyright © 2017 Elsevier B.V. All rights reserved.

Computational design and application of endogenous promoters for transcriptionally targeted gene therapy for rheumatoid arthritis.

NARCIS (Netherlands)

Geurts, J.; Joosten, L.A.B.; Takahashi, N.; Arntz, O.J.; Gluck, A.; Bennink, M.B.; Berg, W.B. van den; Loo, F.A.J. van de

2009-01-01

The promoter regions of genes that are differentially regulated in the synovial membrane during the course of rheumatoid arthritis (RA) represent attractive candidates for application in transcriptionally targeted gene therapy. In this study, we applied an unbiased computational approach to define

Differential methylation at the RELN gene promoter in temporal cortex from autistic and typically developing post-puberal subjects.

Science.gov (United States)

Lintas, Carla; Sacco, Roberto; Persico, Antonio M

2016-01-01

Reelin plays a pivotal role in neurodevelopment and in post-natal synaptic plasticity and has been implicated in the pathogenesis of autism spectrum disorder (ASD). The reelin (RELN) gene expression is significantly decreased in ASD, both in the brain and peripherally. Methylation at the RELN gene promoter is largely triggered at puberty, and hypermethylation has been found in post-mortem brains of schizophrenic and bipolar patients. In this study, we assessed RELN gene methylation status in post-mortem temporocortical tissue samples (BA41/42 or 22) of six pairs of post-puberal individuals with ASD and typically developing subjects, matched for sex (male:female, M:F = 5:1), age, and post-mortem interval. ASD patients display a significantly higher number of methylated CpG islands and heavier methylation in the 5' region of the RELN gene promoter, spanning from -458 to -223 bp, whereas controls have more methylated CpG positions and greater extent of methylation at the 3' promoter region, spanning from -222 to +1 bp. The most upstream promoter region (-458 to -364 bp) is methylated only in ASD brains, while the most downstream region (-131 to +1 bp) is methylated exclusively in control brains. Within this general framework, three different methylation patterns are discernible, each correlated with different extents of reduction in reelin gene expression among ASD individuals compared to controls. The methylation pattern is different in ASD and control post-mortem brains. ASD-specific CpG positions, located in the most upstream gene promoter region, may exert a functional role potentially conferring ASD risk by blunting RELN gene expression.

Putative DNA G-quadruplex formation within the promoters of Plasmodium falciparum var genes

Directory of Open Access Journals (Sweden)

Rowe J

2009-08-01

Full Text Available Abstract Background Guanine-rich nucleic acid sequences are capable of folding into an intramolecular four-stranded structure called a G-quadruplex. When found in gene promoter regions, G-quadruplexes can downregulate gene expression, possibly by blocking the transcriptional machinery. Here we have used a genome-wide bioinformatic approach to identify Putative G-Quadruplex Sequences (PQS in the Plasmodium falciparum genome, along with biophysical techniques to examine the physiological stability of P. falciparum PQS in vitro. Results We identified 63 PQS in the non-telomeric regions of the P. falciparum clone 3D7. Interestingly, 16 of these PQS occurred in the upstream region of a subset of the P. falciparum var genes (group B var genes. The var gene family encodes PfEMP1, the parasite's major variant antigen and adhesin expressed at the surface of infected erythrocytes, that plays a key role in malaria pathogenesis and immune evasion. The ability of the PQS found in the upstream regions of group B var genes (UpsB-Q to form stable G-quadruplex structures in vitro was confirmed using 1H NMR, circular dichroism, UV spectroscopy, and thermal denaturation experiments. Moreover, the synthetic compound BOQ1 that shows a higher affinity for DNA forming quadruplex rather than duplex structures was found to bind with high affinity to the UpsB-Q. Conclusion This is the first demonstration of non-telomeric PQS in the genome of P. falciparum that form stable G-quadruplexes under physiological conditions in vitro. These results allow the generation of a novel hypothesis that the G-quadruplex sequences in the upstream regions of var genes have the potential to play a role in the transcriptional control of this major virulence-associated multi-gene family.

Cloning and characterization of the promoter regions from the parent and paralogous creatine transporter genes.

Science.gov (United States)

Ndika, Joseph D T; Lusink, Vera; Beaubrun, Claudine; Kanhai, Warsha; Martinez-Munoz, Cristina; Jakobs, Cornelis; Salomons, Gajja S

2014-01-10

Interconversion between phosphocreatine and creatine, catalyzed by creatine kinase is crucial in the supply of ATP to tissues with high energy demand. Creatine's importance has been established by its use as an ergogenic aid in sport, as well as the development of intellectual disability in patients with congenital creatine deficiency. Creatine biosynthesis is complemented by dietary creatine uptake. Intracellular transport of creatine is carried out by a creatine transporter protein (CT1/CRT/CRTR) encoded by the SLC6A8 gene. Most tissues express this gene, with highest levels detected in skeletal muscle and kidney. There are lower levels of the gene detected in colon, brain, heart, testis and prostate. The mechanism(s) by which this regulation occurs is still poorly understood. A duplicated unprocessed pseudogene of SLC6A8-SLC6A10P has been mapped to chromosome 16p11.2 (contains the entire SLC6A8 gene, plus 2293 bp of 5'flanking sequence and its entire 3'UTR). Expression of SLC6A10P has so far only been shown in human testis and brain. It is still unclear as to what is the function of SLC6A10P. In a patient with autism, a chromosomal breakpoint that intersects the 5'flanking region of SLC6A10P was identified; suggesting that SLC6A10P is a non-coding RNA involved in autism. Our aim was to investigate the presence of cis-acting factor(s) that regulate expression of the creatine transporter, as well as to determine if these factors are functionally conserved upstream of the creatine transporter pseudogene. Via gene-specific PCR, cloning and functional luciferase assays we identified a 1104 bp sequence proximal to the mRNA start site of the SLC6A8 gene with promoter activity in five cell types. The corresponding 5'flanking sequence (1050 bp) on the pseudogene also had promoter activity in all 5 cell lines. Surprisingly the pseudogene promoter was stronger than that of its parent gene in 4 of the cell lines tested. To the best of our knowledge, this is the first

Identification, occurrence, and validation of DRE and ABRE Cis-regulatory motifs in the promoter regions of genes of Arabidopsis thaliana.

Science.gov (United States)

Mishra, Sonal; Shukla, Aparna; Upadhyay, Swati; Sanchita; Sharma, Pooja; Singh, Seema; Phukan, Ujjal J; Meena, Abha; Khan, Feroz; Tripathi, Vineeta; Shukla, Rakesh Kumar; Shrama, Ashok

2014-04-01

Plants posses a complex co-regulatory network which helps them to elicit a response under diverse adverse conditions. We used an in silico approach to identify the genes with both DRE and ABRE motifs in their promoter regions in Arabidopsis thaliana. Our results showed that Arabidopsis contains a set of 2,052 genes with ABRE and DRE motifs in their promoter regions. Approximately 72% or more of the total predicted 2,052 genes had a gap distance of less than 400 bp between DRE and ABRE motifs. For positional orientation of the DRE and ABRE motifs, we found that the DR form (one in direct and the other one in reverse orientation) was more prevalent than other forms. These predicted 2,052 genes include 155 transcription factors. Using microarray data from The Arabidopsis Information Resource (TAIR) database, we present 44 transcription factors out of 155 which are upregulated by more than twofold in response to osmotic stress and ABA treatment. Fifty-one transcripts from the one predicted above were validated using semiquantitative expression analysis to support the microarray data in TAIR. Taken together, we report a set of genes containing both DRE and ABRE motifs in their promoter regions in A. thaliana, which can be useful to understand the role of ABA under osmotic stress condition. © 2013 Institute of Botany, Chinese Academy of Sciences.

The enrichment of TATA box and the scarcity of depleted proximal nucleosome in the promoters of duplicated yeast genes.

Science.gov (United States)

Kim, Yuseob; Lee, Jang H; Babbitt, Gregory A

2010-01-01

Population genetic theory of gene duplication suggests that the preservation of duplicate copies requires functional divergence upon duplication. Genes that can be readily modified to produce new gene expression patterns may thus be duplicated often. In yeast, genes exhibit dichotomous expression patterns based on their promoter architectures. The expression of genes that contain TATA box or occupied proximal nucleosome (OPN) tends to be variable and respond to external signals. On the other hand, genes without TATA box or with depleted proximal nucleosome (DPN) are expressed constitutively. We find that recent duplicates in the yeast genome are heavily biased to be TATA box containing genes and not to be DPN genes. This suggests that variably expressed genes, due to the functional organization in their promoters, have higher duplicability than constitutively expressed genes.

Mechanism of selective recruitment of RNA polymerases II and III to snRNA gene promoters.

Science.gov (United States)

Dergai, Oleksandr; Cousin, Pascal; Gouge, Jerome; Satia, Karishma; Praz, Viviane; Kuhlman, Tracy; Lhôte, Philippe; Vannini, Alessandro; Hernandez, Nouria

2018-05-01

RNA polymerase II (Pol II) small nuclear RNA (snRNA) promoters and type 3 Pol III promoters have highly similar structures; both contain an interchangeable enhancer and "proximal sequence element" (PSE), which recruits the SNAP complex (SNAPc). The main distinguishing feature is the presence, in the type 3 promoters only, of a TATA box, which determines Pol III specificity. To understand the mechanism by which the absence or presence of a TATA box results in specific Pol recruitment, we examined how SNAPc and general transcription factors required for Pol II or Pol III transcription of SNAPc-dependent genes (i.e., TATA-box-binding protein [TBP], TFIIB, and TFIIA for Pol II transcription and TBP and BRF2 for Pol III transcription) assemble to ensure specific Pol recruitment. TFIIB and BRF2 could each, in a mutually exclusive fashion, be recruited to SNAPc. In contrast, TBP-TFIIB and TBP-BRF2 complexes were not recruited unless a TATA box was present, which allowed selective and efficient recruitment of the TBP-BRF2 complex. Thus, TBP both prevented BRF2 recruitment to Pol II promoters and enhanced BRF2 recruitment to Pol III promoters. On Pol II promoters, TBP recruitment was separate from TFIIB recruitment and enhanced by TFIIA. Our results provide a model for specific Pol recruitment at SNAPc-dependent promoters. © 2018 Dergai et al.; Published by Cold Spring Harbor Laboratory Press.

The promoter of the Arabidopsis thaliana plastocyanin gene contains a far upstream enhancer-like element involved in chloroplast-dependent expression.

Science.gov (United States)

Vorst, O; Kock, P; Lever, A; Weterings, B; Weisbeek, P; Smeekens, S

1993-12-01

Plastocyanin is part of the photosynthetic electron transport chain in the chloroplast and is encoded in the nucleus. Expression of the Arabidopsis thaliana plastocyanin gene is organ specific: high mRNA levels are observed in young green parts of the plant. Furthermore, expression is dependent on the presence of light and functional chloroplasts. When grown in the presence of norflurazon under white light conditions, resulting in the photo-oxidative destruction of the chloroplast, plastocyanin mRNA levels are strongly reduced. A -1579 to -9 promoter fragment confers light-regulated and chloroplast-dependent expression to the beta-glucuronidase reporter gene in transgenic tobacco plants. This suggests that regulation takes place at the level of transcription. A plastocyanin promoter deletion series ranging from -1579 to -121 which was also tested in tobacco, revealed the presence of a strong positive regulating element (PRE) in the -1579 to -705 region. Deletion of this part of the promoter resulted in a approximately 100-fold reduction of GUS expression as measured in mature leaves. Surprisingly, this enhancer-like element was capable of stimulating transcription from a position downstream of its reporter. Moreover, it could also activate a truncated CaMV 35S promoter. Deletion of this element coincides with the loss of chloroplast-dependency of reporter gene expression, as judged by norflurazon treatment of transgenic seedlings. So, the activity of the PRE itself might depend on the presence of functional chloroplasts.

Halophytes: Potential Resources for Salt Stress Tolerance Genes and Promoters

Directory of Open Access Journals (Sweden)

Avinash Mishra

2017-05-01

Full Text Available Halophytes have demonstrated their capability to thrive under extremely saline conditions and thus considered as one of the best germplasm for saline agriculture. Salinity is a worldwide problem, and the salt-affected areas are increasing day-by-day because of scanty rainfall, poor irrigation system, salt ingression, water contamination, and other environmental factors. The salinity stress tolerance mechanism is a very complex phenomenon, and some pathways are coordinately linked for imparting salinity tolerance. Though a number of salt responsive genes have been reported from the halophytes, there is always a quest for promising stress-responsive genes that can modulate plant physiology according to the salt stress. Halophytes such as Aeluropus, Mesembryanthemum, Suaeda, Atriplex, Thellungiella, Cakile, and Salicornia serve as a potential candidate for the salt-responsive genes and promoters. Several known genes like antiporters (NHX, SOS, HKT, VTPase, ion channels (Cl−, Ca2+, aquaporins, antioxidant encoding genes (APX, CAT, GST, BADH, SOD and some novel genes such as USP, SDR1, SRP etc. were isolated from halophytes and explored for developing stress tolerance in the crop plants (glycophytes. It is evidenced that stress triggers salt sensors that lead to the activation of stress tolerance mechanisms which involve multiple signaling proteins, up- or down-regulation of several genes, and finally the distinctive or collective effects of stress-responsive genes. In this review, halophytes are discussed as an excellent platform for salt responsive genes which can be utilized for developing salinity tolerance in crop plants through genetic engineering.

A mutation in a functional Sp1 binding site of the telomerase RNA gene (hTERC promoter in a patient with Paroxysmal Nocturnal Haemoglobinuria

Directory of Open Access Journals (Sweden)

Mason Philip J

2004-06-01

Full Text Available Abstract Background Mutations in the gene coding for the RNA component of telomerase, hTERC, have been found in autosomal dominant dyskeratosis congenita (DC and aplastic anemia. Paroxysmal nocturnal hemoglobinuria (PNH is a clonal blood disorder associated with aplastic anemia and characterized by the presence of one or more clones of blood cells lacking glycosylphosphatidylinositol (GPI anchored proteins due to a somatic mutation in the PIGA gene. Methods We searched for mutations in DNA extracted from PNH patients by amplification of the hTERC gene and denaturing high performance liquid chromatography (dHPLC. After a mutation was found in a potential transcription factor binding site in one patient electrophoretic mobility shift assays were used to detect binding of transcription factors to that site. The effect of the mutation on the function of the promoter was tested by transient transfection constructs in which the promoter is used to drive a reporter gene. Results Here we report the finding of a novel promoter mutation (-99C->G in the hTERC gene in a patient with PNH. The mutation disrupts an Sp1 binding site and destroys its ability to bind Sp1. Transient transfection assays show that mutations in this hTERC site including C-99G cause either up- or down-regulation of promoter activity and suggest that the site regulates core promoter activity in a context dependent manner in cancer cells. Conclusions These data are the first report of an hTERC promoter mutation from a patient sample which can modulate core promoter activity in vitro, raising the possibility that the mutation may affect the transcription of the gene in hematopoietic stem cells in vivo, and that dysregulation of telomerase may play a role in the development of bone marrow failure and the evolution of PNH clones.

A var gene promoter implicated in severe malaria nucleates silencing and is regulated by 3’ untranslated region and intronic cis-elements

Science.gov (United States)

Muhle, Rebecca A.; Adjalley, Sophie; Falkard, Brie; Nkrumah, Louis J.; Muhle, Michael E.; Fidock, David A.

2009-01-01

Questions surround the mechanism of mutually exclusive expression by which Plasmodium falciparum mediates activation and silencing of var genes. These encode PfEMP1 proteins, which function as cytoadherent and immunomodulatory molecules at the surface of parasitized erythrocytes. Current evidence suggests that promoter silencing by var introns might play a key role in var gene regulation. To evaluate the impact of cis-acting regulatory regions on var silencing, we generated P. falciparum lines in which luciferase was placed under the control of an UpsA var promoter. By utilizing the Bxb1 integrase system, these reporter cassettes were targeted to a genomic region that was not in apposition to var sub-telomeric domains. This eliminated possible effects from surrounding telomeric elements and removed the variability inherent in episomal systems. Studies with highly synchronized parasites revealed that the UpsA element possessed minimal activity in comparison with a heterologous (hrp3) promoter. This may well result from the integrated UpsA promoter being largely silenced by the neighboring cg6 promoter. Our analyses also revealed that the DownsA 3’ untranslated region further decreased the luciferase activity from both cassettes, whereas the var A intron repressed the UpsA promoter specifically. By applying multivariate analysis over the entire cell cycle, we confirmed the significance of these cis-elements and found the parasite stage to be the major factor regulating UpsA promoter activity. Additionally, we observed that the UpsA promoter was capable of nucleating reversible silencing that spread to a downstream promoter. We believe these studies are the first to analyze promoter activity of Group A var genes which have been implicated in severe malaria, and support the model that var introns can further suppress var expression. These data also suggest an important suppressive role for the DownsA terminator. Our findings imply the existence of multiple levels of

The cardiac calsequestrin gene transcription is modulated at the promoter by NFAT and MEF-2 transcription factors.

Directory of Open Access Journals (Sweden)

Rafael Estrada-Avilés

Full Text Available Calsequestrin-2 (CASQ2 is the main Ca2+-binding protein inside the sarcoplasmic reticulum of cardiomyocytes. Previously, we demonstrated that MEF-2 and SRF binding sites within the human CASQ2 gene (hCASQ2 promoter region are functional in neonatal cardiomyocytes. In this work, we investigated if the calcineurin/NFAT pathway regulates hCASQ2 expression in neonatal cardiomyocytes. The inhibition of NFAT dephosphorylation with CsA or INCA-6, reduced both the luciferase activity of hCASQ2 promoter constructs (-3102/+176 bp and -288/+176 bp and the CASQ2 mRNA levels in neonatal rat cardiomyocytes. Additionally, NFATc1 and NFATc3 over-expressing neonatal cardiomyocytes showed a 2-3-fold increase in luciferase activity of both hCASQ2 promoter constructs, which was prevented by CsA treatment. Site-directed mutagenesis of the -133 bp MEF-2 binding site prevented trans-activation of hCASQ2 promoter constructs induced by NFAT overexpression. Chromatin Immunoprecipitation (ChIP assays revealed NFAT and MEF-2 enrichment within the -288 bp to +76 bp of the hCASQ2 gene promoter. Besides, a direct interaction between NFAT and MEF-2 proteins was demonstrated by protein co-immunoprecipitation experiments. Taken together, these data demonstrate that NFAT interacts with MEF-2 bound to the -133 bp binding site at the hCASQ2 gene promoter. In conclusion, in this work, we demonstrate that the Ca2+-calcineurin/NFAT pathway modulates the transcription of the hCASQ2 gene in neonatal cardiomyocytes.

Cell-type specific oxytocin gene expression from AAV delivered promoter deletion constructs into the rat supraoptic nucleus in vivo.

Directory of Open Access Journals (Sweden)

Raymond L Fields

Full Text Available The magnocellular neurons (MCNs in the hypothalamus selectively express either oxytocin (OXT or vasopressin (AVP neuropeptide genes, a property that defines their phenotypes. Here we examine the molecular basis of this selectivity in the OXT MCNs by stereotaxic microinjections of adeno-associated virus (AAV vectors that contain various OXT gene promoter deletion constructs using EGFP as the reporter into the rat supraoptic nucleus (SON. Two weeks following injection of the AAVs, immunohistochemical assays of EGFP expression from these constructs were done to determine whether the EGFP reporter co-localizes with either the OXT- or AVP-immunoreactivity in the MCNs. The results show that the key elements in the OT gene promoter that regulate the cell-type specific expression the SON are located -216 to -100 bp upstream of the transcription start site. We hypothesize that within this 116 bp domain a repressor exists that inhibits expression specifically in AVP MCNs, thereby leading to the cell-type specific expression of the OXT gene only in the OXT MCNs.

Intrinsically bent DNA in replication origins and gene promoters.

Science.gov (United States)

Gimenes, F; Takeda, K I; Fiorini, A; Gouveia, F S; Fernandez, M A

2008-06-24

Intrinsically bent DNA is an alternative conformation of the DNA molecule caused by the presence of dA/dT tracts, 2 to 6 bp long, in a helical turn phase DNA or with multiple intervals of 10 to 11 bp. Other than flexibility, intrinsic bending sites induce DNA curvature in particular chromosome regions such as replication origins and promoters. Intrinsically bent DNA sites are important in initiating DNA replication, and are sometimes found near to regions associated with the nuclear matrix. Many methods have been developed to localize bent sites, for example, circular permutation, computational analysis, and atomic force microscopy. This review discusses intrinsically bent DNA sites associated with replication origins and gene promoter regions in prokaryote and eukaryote cells. We also describe methods for identifying bent DNA sites for circular permutation and computational analysis.

Functional characterization of Pol III U6 promoters for gene knockdown and knockout in Plutella xylostella.

Science.gov (United States)

Huang, Yuping; Wang, Yajun; Zeng, Baosheng; Liu, Zhaoxia; Xu, Xuejiao; Meng, Qian; Huang, Yongping; Yang, Guang; Vasseur, Liette; Gurr, Geoff M; You, Minsheng

2017-10-01

RNA polymerase type III (Pol-III) promoters such as U6 are commonly used to express small RNAs, including short hairpin RNAs (shRNAs) and single guide RNAs (sgRNAs). Functional U6 promoters are widely used in CRISPR systems, and their characterization can facilitate genome editing of non-model organisms. In the present study, six U6 small nuclear RNA (snRNA) promoters containing two conserved elements of a proximal sequence element (PSEA) and a TATA box, were identified and characterized in the diamondback moth (Plutella xylostella) genome. Relative efficiency of the U6 promoters to express shRNA induced EGFP knockdown was tested in a P. xylostella cell line, revealing that the PxU6:3 promoter had the strongest expression effect. Further work with the PxU6:3 promoter showed its efficacy in EGFP knockout using CRISPR/Cas9 system in the cells. The expression plasmids with versatile Pxabd-A gene specific sgRNA driven by the PxU6:3 promoter, combined with Cas9 mRNA, could induce mutagenesis at specific genomic loci in vivo. The phenotypes induced by sgRNA expression plasmids were similar to those done in vitro transcription sgRNAs. A plasmid with two tandem arranged PxU6:3:sgRNA expression cassettes targeting Pxabd-A loci was generated, which caused a 28,856 bp fragment deletion, suggesting that the multi-sgRNA expression plasmid can be used for multi-targeting. Our work indicates that U6 snRNA promoters can be used for functional studies of genes with the approach of reverse genetics in P. xylostella. These essential promoters also provide valuable potential for CRISPR-derived gene drive as a tactic for population control in this globally significant pest. Copyright © 2017 Elsevier Ltd. All rights reserved.

Promoter of CaZF, a chickpea gene that positively regulates growth and stress tolerance, is activated by an AP2-family transcription factor CAP2.

Directory of Open Access Journals (Sweden)

Deepti Jain

Full Text Available Plants respond to different forms of stresses by inducing transcription of a common and distinct set of genes by concerted actions of a cascade of transcription regulators. We previously reported that a gene, CaZF encoding a C2H2-zinc finger family protein from chickpea (Cicer arietinum imparted high salinity tolerance when expressed in tobacco plants. We report here that in addition to promoting tolerance against dehydration, salinity and high temperature, the CaZF overexpressing plants exhibited similar phenotype of growth and development like the plants overexpressing CAP2, encoding an AP2-family transcription factor from chickpea. To investigate any relationship between these two genes, we performed gene expression analysis in the overexpressing plants, promoter-reporter analysis and chromatin immunoprecipitation. A number of transcripts that exhibited enhanced accumulation upon expression of CAP2 or CaZF in tobacco plants were found common. Transient expression of CAP2 in chickpea leaves resulted in increased accumulation of CaZF transcript. Gel mobility shift and transient promoter-reporter assays suggested that CAP2 activates CaZF promoter by interacting with C-repeat elements (CRTs in CaZF promoter. Chromatin immunoprecipitation (ChIP assay demonstrated an in vivo interaction of CAP2 protein with CaZF promoter.

Cloning and Functional Analysis of the Promoter of an Ascorbate Oxidase Gene from Gossypium hirsutum

OpenAIRE

Xin, Shan; Tao, Chengcheng; Li, Hongbin

2016-01-01

Apoplastic ascorbate oxidase (AO) plays significant roles in plant cell growth. However, the mechanism of underlying the transcriptional regulation of AO in Gossypium hirsutum remains unclear. Here, we obtained a 1,920-bp promoter sequence from the Gossypium hirsutum ascorbate oxidase (GhAO1) gene, and this GhAO1 promoter included a number of known cis-elements. Promoter activity analysis in overexpressing pGhAO1::GFP-GUS tobacco (Nicotiana benthamiana) showed that the GhAO1 promoter exhibite...

CAGE-defined promoter regions of the genes implicated in Rett Syndrome

DEFF Research Database (Denmark)

Vitezic, Morana; Bertin, Nicolas; Andersson, Robin

2014-01-01

BACKGROUND: Mutations in three functionally diverse genes cause Rett Syndrome. Although the functions of Forkhead box G1 (FOXG1), Methyl CpG binding protein 2 (MECP2) and Cyclin-dependent kinase-like 5 (CDKL5) have been studied individually, not much is known about their relation to each other...... reveal the predominantly used transcription start sites (TSSs) for each gene including novel transcription start sites for FOXG1. We show that FOXG1 expression is poorly correlated with the expression of MECP2 and CDKL5. We identify promoter shapes for each TSS, the predicted location of enhancers...

Hypermethylation of E-Cadherin and Estrogen Receptor-a Gene Promoter and Its Association with Clinicopathological Features of Breast Cancer in Iranian Patients

Directory of Open Access Journals (Sweden)

Mozhgan Rasti

2009-06-01

Full Text Available Background: Aberrant methylation of cytosine-guanine dinucleotideislands leads to inactivation of tumor suppressorgenes in breast cancer. Tumor suppressor genes are unmethylatedin normal tissue and often become hypermethylatedduring tumor formation, leading to gene silencing. We investigatedthe association between E-cadherin (CDH1 and estrogenreceptor-α (ESRα gene promoter methylation andmajor clinical and pathological features of breast cancer inIranian women.Methods: DNA was extracted from 67 primary breast tumorsand gene promoter methylation was analyzed by methylationspecificpolymerase chain reaction method.Results: Fifty percent of the samples showed aberrant methylationin at least one of the two tested loci. We detectedCDH1 hypermethylation in 41% of invasive tumors and receptor-α gene hypermethylation in 18% of invasive tumorsamples. We found no association between CDH1 and receptor-α gene hypermethylation (P=0.45. There was a correlationbetween hypermethylation of CDH1 locus and tumorsize ≥5 cm (P=0.019.Conclusion: Our data suggest that the malignant progressionof human ductal and lobular breast carcinoma in Iranianwomen involves a heterogeneous pattern of cytosine-guaninedinucleotide island hypermethylation of the CDH1 gene.

Promoter Analysis Reveals Globally Differential Regulation of Human Long Non-Coding RNA and Protein-Coding Genes

KAUST Repository

Alam, Tanvir; Medvedeva, Yulia A.; Jia, Hui; Brown, James B.; Lipovich, Leonard; Bajic, Vladimir B.

2014-01-01

raise the possibility that, given the historical reliance on protein-coding gene catalogs to define the chromatin states of active promoters, a revision of these chromatin signature profiles to incorporate expressed lncRNA genes is warranted

Differential transcriptional regulation of banana sucrose phosphate synthase gene in response to ethylene, auxin, wounding, low temperature and different photoperiods during fruit ripening and functional analysis of banana SPS gene promoter.

Science.gov (United States)

Roy Choudhury, Swarup; Roy, Sujit; Das, Ranjan; Sengupta, Dibyendu N

2008-12-01

Sucrose phosphate synthase (SPS) (EC 2.3.1.14) is the key regulatory component in sucrose formation in banana (Musa acuminata subgroup Cavendish, cv Giant governor) fruit during ripening. This report illustrates differential transcriptional responses of banana SPS gene following ethylene, auxin, wounding, low temperature and different photoperiods during ripening in banana fruit. Whereas ethylene strongly stimulated SPS transcript accumulation, auxin and cold treatment only marginally increased the abundance of SPS mRNA level, while wounding negatively regulated SPS gene expression. Conversely, SPS transcript level was distinctly increased by constant exposure to white light. Protein level, enzymatic activity of SPS and sucrose synthesis were substantially increased by ethylene and increased exposure to white light conditions as compared to other treatments. To further study the transcriptional regulation of SPS in banana fruit, the promoter region of SPS gene was cloned and some cis-acting regulatory elements such as a reverse GCC-box ERE, two ARE motifs (TGTCTC), one LTRE (CCGAA), a GAGA-box (GAGA...) and a GATA-box LRE (GATAAG) were identified along with the TATA and CAAT-box. DNA-protein interaction studies using these cis-elements indicated a highly specific cis-trans interaction in the banana nuclear extract. Furthermore, we specifically studied the light responsive characteristics of GATA-box containing synthetic as well as native banana SPS promoter. Transient expression assays using banana SPS promoter have also indicated the functional importance of the SPS promoter in regulating gene expression. Together, these results provide insights into the transcriptional regulation of banana SPS gene in response to phytohormones and other environmental factors during fruit ripening.

Identification of a p53-response element in the promoter of the proline oxidase gene

International Nuclear Information System (INIS)

Maxwell, Steve A.; Kochevar, Gerald J.

2008-01-01

Proline oxidase (POX) is a p53-induced proapoptotic gene. We investigated whether p53 could bind directly to the POX gene promoter. Chromatin immunoprecipitation (ChIP) assays detected p53 bound to POX upstream gene sequences. In support of the ChIP results, sequence analysis of the POX gene and its 5' flanking sequences revealed a potential p53-binding site, GGGCTTGTCTTCGTGTGACTTCTGTCT, located at 1161 base pairs (bp) upstream of the transcriptional start site. A 711-bp DNA fragment containing the candidate p53-binding site exhibited reporter gene activity that was induced by p53. In contrast, the same DNA region lacking the candidate p53-binding site did not show significant p53-response activity. Electrophoretic mobility shift assay (EMSA) in ACHN renal carcinoma cell nuclear lysates confirmed that p53 could bind to the 711-bp POX DNA fragment. We concluded from these experiments that a p53-binding site is positioned at -1161 to -1188 bp upstream of the POX transcriptional start site

Mediator subunit MED1 is a T3-dependent and T3-independent coactivator on the thyrotropin β gene promoter

Energy Technology Data Exchange (ETDEWEB)

Matsui, Keiji; Oda, Kasumi; Mizuta, Shumpei; Ishino, Ruri; Urahama, Norinaga; Hasegawa, Natsumi [Laboratory of Hematology, Division of Medical Biophysics, Kobe University Graduate School of Health Sciences, 7-10-2 Tomogaoka, Suma-ku, Kobe 654-0142 (Japan); Roeder, Robert G. [Laboratory of Biochemistry and Molecular Biology, The Rockefeller University, 1230 York Avenue, New York, NY 10065 (United States); Ito, Mitsuhiro, E-mail: itomi@med.kobe-u.ac.jp [Laboratory of Hematology, Division of Medical Biophysics, Kobe University Graduate School of Health Sciences, 7-10-2 Tomogaoka, Suma-ku, Kobe 654-0142 (Japan); Laboratory of Biochemistry and Molecular Biology, The Rockefeller University, 1230 York Avenue, New York, NY 10065 (United States); Department of Family and Community Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 654-0142 (Japan); Consolidated Research Institute for Advanced Science and Medical Care, Waseda University, 3-4-1 Okubo, Shinjuku-ku, Tokyo 159-8555 (Japan)

2013-10-11

Highlights: •MED1 is a bona fide T3-dependent coactivator on TSHB promoter. •Mice with LxxLL-mutant MED1 have attenuated TSHβ mRNA and thyroid hormone levels. •MED1 activates TSHB promoter T3-dependently in cultured cells. •T3-dependent MED1 action is enhanced when SRC1/SRC2 or HDAC2 is downregulated. •MED1 is also a T3-independent GATA2/Pit1 coactivator on TSHB promoter. -- Abstract: The MED1 subunit of the Mediator transcriptional coregulator complex is a nuclear receptor-specific coactivator. A negative feedback mechanism of thyroid-stimulating hormone (TSH, or thyrotropin) expression in the thyrotroph in the presence of triiodothyronine (T3) is employed by liganded thyroid hormone receptor β (TRβ) on the TSHβ gene promoter, where conventional histone-modifying coactivators act as corepressors. We now provide evidence that MED1 is a ligand-dependent positive cofactor on this promoter. TSHβ gene transcription was attenuated in MED1 mutant mice in which the nuclear receptor-binding ability of MED1 was specifically disrupted. MED1 stimulated GATA2- and Pit1-mediated TSHβ gene promoter activity in a ligand-independent manner in cultured cells. MED1 also stimulated transcription from the TSHβ gene promoter in a T3-dependent manner. The transcription was further enhanced when the T3-dependent corepressors SRC1, SRC2, and HDAC2 were downregulated. Hence, MED1 is a T3-dependent and -independent coactivator on the TSHβ gene promoter.

Evaluation of promoter methylation status of MLH1 gene in Iranian patients with colorectal tumors and adenoma polyps.

Science.gov (United States)

Zarandi, Ashkan; Irani, Shiva; Savabkar, Sanaz; Chaleshi, Vahid; Ghavideldarestani, Maryam; Mirfakhraie, Reza; Khodadoostan, Mahsa; Nazemalhosseini-Mojarad, Ehsan; Asadzadeh Aghdaei, Hamid

2017-01-01

The aim of this study was to evaluate the methylation status of the promoter region of MLH1 gene in colorectal cancer (CRC) and its precursor lesions as well as elucidate its association with various clinicopathological characteristics among Iranian population. Epigenetic silencing of mismatch repair genes, such as MLH1 , by methylation of CpG islands of their promoter region has been proved to be an important mechanism in colorectal carcinogenesis. Fifty colorectal cancer and polyp tissue samples including 13 Primary colorectal tumor and 37 Adenoma polyp samples were enrolled in this study. Methylation-specific polymerase chain reaction (MSP) was performed to find the frequency of MLH1 Promoter Methylation. Promoter methylation of MLH1 gene was detected in 5 out of 13 tumor tissues and 4 out of 37 adenoma polyp. The frequency of MLH1 methylation in tumor samples was significantly higher compared to that in polyp tissues (P= 0.026). No significant association was observed between MLH1 promoter methylation and clinicopathological characteristics of the patients. The frequency of  MLH1  promoter methylation in CRC and colon polyp was 18%. Our findings indicated that methylation of MLH1 promoter region alone cannot be considered as a biomarker for early detection of CRC.

The relationship in Japanese infants between a genetic polymorphism in the promoter region of the insulin-like growth factor I gene and the plasma level.

Science.gov (United States)

Kinoshita, Yumiko; Kizaki, Zenro; Ishihara, Yasunori; Nakajima, Hisakazu; Adachi, Shinsuke; Kosaka, Kitaro; Kinugasa, Akihiko; Sugimoto, Tohru

2007-01-01

Evidence is accumulating that the promoter region of the insulin-like growth factor I (IGF-I) gene polymorphism and low levels of IGF-I are associated with type 2 diabetes, cardiovascular disease and birth weight; however, the number of wild-type alleles is different in each country. This study aimed to examine the 737/738 marker, a cytosine-adenine repeat in the promoter region of the IGF-I gene polymorphism, and plasma IGF-I levels in Japanese infants and analyze the genetic background. Data were collected for 15 months in Kyoto Prefectural University of Medicine. The body composition parameters of all infants were determined at birth. At 5 days after birth, we took blood samples to measure the product size of the promoter region of the IGF-I gene polymorphism and plasma IGF-I. In a population-based sample of 160 subjects, 6 different alleles and 16 genotypes were identified in the promoter region of the IGF-I gene polymorphism. The existence of a 196-bp allele has proved to result in a low plasma IGF-I level, a small head and chest circumference (p body composition parameters in Japanese infants. Our results suggest genetical influence on prenatal growth and serum IGF-I levels.

SNP variation in the promoter of the PRKAG3 gene and association with meat quality traits in pig.

Science.gov (United States)

Ryan, Marion T; Hamill, Ruth M; O'Halloran, Aisling M; Davey, Grace C; McBryan, Jean; Mullen, Anne M; McGee, Chris; Gispert, Marina; Southwood, Olwen I; Sweeney, Torres

2012-07-25

The PRKAG3 gene encodes the γ3 subunit of adenosine monophosphate activated protein kinase (AMPK), a protein that plays a key role in energy metabolism in skeletal muscle. Non-synonymous single nucleotide polymorphisms (SNPs) in this gene such as I199V are associated with important pork quality traits. The objective of this study was to investigate the relationship between gene expression of the PRKAG3 gene, SNP variation in the PRKAG3 promoter and meat quality phenotypes in pork. PRKAG3 gene expression was found to correlate with a number of traits relating to glycolytic potential (GP) and intramuscular fat (IMF) in three phenotypically diverse F1 crosses comprising of 31 Large White, 23 Duroc and 32 Pietrain sire breeds. The majority of associations were observed in the Large White cross. There was a significant association between genotype at the g.-311A>G locus and PRKAG3 gene expression in the Large White cross. In the same population, ten novel SNPs were identified within a 1.3 kb region spanning the promoter and from this three major haplotypes were inferred. Two tagging SNPs (g.-995A>G and g.-311A>G) characterised the haplotypes within the promoter region being studied. These two SNPs were subsequently genotyped in larger populations consisting of Large White (n = 98), Duroc (n = 99) and Pietrain (n = 98) purebreds. Four major haplotypes including promoter SNP's g.-995A>G and g.-311A>G and I199V were inferred. In the Large White breed, HAP1 was associated with IMF% in the M. longissmus thoracis et lumborum (LTL) and driploss%. HAP2 was associated with IMFL% GP-influenced traits pH at 24 hr in LTL (pHULT), pH at 45 min in LTL (pH(45)LT) and pH at 45 min in the M. semimembranosus muscle (pH(45)SM). HAP3 was associated with driploss%, pHULT pH(45)LT and b* Minolta. In the Duroc breed, associations were observed between HAP1 and driploss% and pHUSM. No associations were observed with the remaining haplotypes (HAP2, HAP3 and HAP4) in the Duroc breed. The

Generation of an efficient artificial promoter of bovine skeletal muscle α-actin gene (ACTA1) through addition of cis-acting element.

Science.gov (United States)

Hu, Qian; Tong, Huili; Zhao, Dandan; Cao, Yunkao; Zhang, Weiwei; Chang, Shuwei; Yang, Yu; Yan, Yunqin

2015-03-01

The promoter of skeletal muscle α-actin gene (ACTA1) is highly muscle specific. The core of the bovine ACTA1 promoter extends from +29 to -233, about 262 base pairs (bp), which is sufficient to activate transcription in bovine muscle satellite cells. In this study, analysis by PCR site-specific mutagenesis showed that the cis-acting element SRE (serum response element binding factor) was processed as a transcriptional activator. In order to enhance the bovine ACTA1 promoter's activity, we used a strategy to modify it. We cloned a fragment containing three SREs from the promoter of ACTA1, and then one or two clones were linked upstream of the core promoter (262 bp) of ACTA1. One and two clones increased the activity of the ACTA1 promoter 3-fold and 10-fold, respectively, and maintained muscle tissue specificity. The modified promoter with two clones could increase the level of ACTA1 mRNA and protein 4-fold and 1.1-fold, respectively. Immunofluorescence results showed that green fluorescence of ACTA1 increased. Additionally, the number of total muscle microfilaments increased. These genetically engineered promoters might be useful for regulating gene expression in muscle cells and improving muscle mass in livestock.

Pairwise comparisons of ten porcine tissues identify differential transcriptional regulation at the gene, isoform, promoter and transcription start site level

International Nuclear Information System (INIS)

Farajzadeh, Leila; Hornshøj, Henrik; Momeni, Jamal; Thomsen, Bo; Larsen, Knud; Hedegaard, Jakob; Bendixen, Christian; Madsen, Lone Bruhn

2013-01-01

Highlights: •Transcriptome sequencing yielded 223 mill porcine RNA-seq reads, and 59,000 transcribed locations. •Establishment of unique transcription profiles for ten porcine tissues including four brain tissues. •Comparison of transcription profiles at gene, isoform, promoter and transcription start site level. •Highlights a high level of regulation of neuro-related genes at both gene, isoform, and TSS level. •Our results emphasize the pig as a valuable animal model with respect to human biological issues. -- Abstract: The transcriptome is the absolute set of transcripts in a tissue or cell at the time of sampling. In this study RNA-Seq is employed to enable the differential analysis of the transcriptome profile for ten porcine tissues in order to evaluate differences between the tissues at the gene and isoform expression level, together with an analysis of variation in transcription start sites, promoter usage, and splicing. Totally, 223 million RNA fragments were sequenced leading to the identification of 59,930 transcribed gene locations and 290,936 transcript variants using Cufflinks with similarity to approximately 13,899 annotated human genes. Pairwise analysis of tissues for differential expression at the gene level showed that the smallest differences were between tissues originating from the porcine brain. Interestingly, the relative level of differential expression at the isoform level did generally not vary between tissue contrasts. Furthermore, analysis of differential promoter usage between tissues, revealed a proportionally higher variation between cerebellum (CBE) versus frontal cortex and cerebellum versus hypothalamus (HYP) than in the remaining comparisons. In addition, the comparison of differential transcription start sites showed that the number of these sites is generally increased in comparisons including hypothalamus in contrast to other pairwise assessments. A comprehensive analysis of one of the tissue contrasts, i

COX-2 gene expression in colon cancer tissue related to regulating factors and promoter methylation status

Directory of Open Access Journals (Sweden)

Lagerstedt Kristina

2011-06-01

Full Text Available Abstract Background Increased cyclooxygenase activity promotes progression of colorectal cancer, but the mechanisms behind COX-2 induction remain elusive. This study was therefore aimed to define external cell signaling and transcription factors relating to high COX-2 expression in colon cancer tissue. Method Tumor and normal colon tissue were collected at primary curative operation in 48 unselected patients. COX-2 expression in tumor and normal colon tissue was quantified including microarray analyses on tumor mRNA accounting for high and low tumor COX-2 expression. Cross hybridization was performed between tumor and normal colon tissue. Methylation status of up-stream COX-2 promoter region was evaluated. Results Tumors with high COX-2 expression displayed large differences in gene expression compared to normal colon. Numerous genes with altered expression appeared in tumors of high COX-2 expression compared to tumors of low COX-2. COX-2 expression in normal colon was increased in patients with tumors of high COX-2 compared to normal colon from patients with tumors of low COX-2. IL1β, IL6 and iNOS transcripts were up-regulated among external cell signaling factors; nine transcription factors (ATF3, C/EBP, c-Fos, Fos-B, JDP2, JunB, c-Maf, NF-κB, TCF4 showed increased expression and 5 (AP-2, CBP, Elk-1, p53, PEA3 were decreased in tumors with high COX-2. The promoter region of COX-2 gene did not show consistent methylation in tumor or normal colon tissue. Conclusions Transcription and external cell signaling factors are altered as covariates to COX-2 expression in colon cancer tissue, but DNA methylation of the COX-2 promoter region was not a significant factor behind COX-2 expression in tumor and normal colon tissue.

Promoter polymorphisms of ST3GAL4 and ST6GAL1 genes and associations with risk of premalignant and malignant lesions of the cervix.

Science.gov (United States)

Rivera-Juarez, Maria de Los Angeles; Rosas-Murrieta, Nora Hilda; Mendieta-Carmona, Victoriano; Hernandez-Pacheco, Raquel Esneidy; Zamora-Ginez, Irma; Rodea-Avila, Carlos; Apresa-Garcia, Teresa; Garay-Villar, Onix; Aguilar-Lemarroy, Adriana; Jave-Suarez, Luis Felipe; Diaz-Orea, Maria Alicia; Milflores-Flores, Lorena; Reyes-Salinas, Juan Salvador; Ceja-Utrera, Francisco Javier; Vazquez-Zamora, Victor Javier; Vargas-Maldonado, Tomas; Reyes-Carmona, Sandra; Sosa-Jurado, Francisca; Santos-Lopez, Gerardo; Reyes-Leyva, Julio; Vallejo-Ruiz, Veronica

2014-01-01

Sialyltransferase gene expression is altered in several cancers, including examples in the cervix. Transcriptional regulation of the responsible genes depends on different promoters. We aimed to determine the association of single-nucleotide polymorphisms in the B3 promoter of the ST3GAL4 gene and the P1 promoter of the ST6GAL1 gene with cervical premalignant lesions or cervical cancer. A blood sample and/or cervical scrapes were obtained from 104 women with normal cytology, 154 with premalignant lesions and 100 with cervical cancer. We also included 119 blood samples of random donors. The polymorphisms were identified by sequencing from PCR products. For the B3 promoter, a fragment of 506 bp (from nucleotide -408 to +98) was analyzed, and for the P1 promoter a 490 bp (-326 to +164) fragment. The polymorphism analysis showed that at SNP rs10893506, genotypes CC and CT of the ST3GAL4 B3 promoter were associated with the presence of premalignant lesions (OR=2.89; 95%CI 1.72-4.85) and cervical cancer (OR=2.23; 95%CI 1.27-3.91). We detected only one allele of each polymorphism in the ST6GAL1 P1 promoter. We did not detect any genetic variability in the P1 promoter region in our study population. Our results suggest that the rs10893506 polymorphism -22C/T may increase susceptibility to premalignant and malignant lesions of the cervix.

Inactivation of promoter 1B of APC causes partial gene silencing: evidence for a significant role of the promoter in regulation and causative of familial adenomatous polyposis

DEFF Research Database (Denmark)

Rohlin, A; Engwall, Y; Fritzell, K

2011-01-01

inactivation of promoter 1B is disease causing in FAP; (ii) expression of transcripts from promoter 1B is generated at considerable higher levels compared with 1A, demonstrating a hitherto unknown importance of 1B; (iii) adenoma formation in FAP, caused by impaired function of promoter 1B, does not require......Familial adenomatous polyposis (FAP) is caused by germline mutations in the adenomatous polyposis coli (APC) gene. Two promoters, 1A and 1B, have been recognized in APC, and 1B is thought to have a minor role in the regulation of the gene. We have identified a novel deletion encompassing half...... of this promoter in the largest family (Family 1) of the Swedish Polyposis Registry. The mutation leads to an imbalance in allele-specific expression of APC, and transcription from promoter 1B was highly impaired in both normal colorectal mucosa and blood from mutation carriers. To establish the significance...

miR-31 and its host gene lncRNA LOC554202 are regulated by promoter hypermethylation in triple-negative breast cancer

Directory of Open Access Journals (Sweden)

Augoff Katarzyna

2012-01-01

Full Text Available Abstract Background microRNAs have been established as powerful regulators of gene expression in normal physiological as well as in pathological conditions, including cancer progression and metastasis. Recent studies have demonstrated a key role of miR-31 in the progression and metastasis of breast cancer. Downregulation of miR-31 enhances several steps of the invasion-metastasis cascade in breast cancer, i.e., local invasion, extravasation and survival in the circulation system, and metastatic colonization of distant sites. miR-31 exerts its metastasis-suppressor activity by targeting a cohort of pro-metastatic genes, including RhoA and WAVE3. The molecular mechanisms that lead to the loss of miR-31 and the activation of its pro-metastatic target genes during these specific steps of the invasion-metastasis cascade are however unknown. Results In the present report, we identify promoter hypermethylation as one of the major mechanisms for silencing miR-31 in breast cancer, and in the triple-negative breast cancer (TNBC cell lines of basal subtype, in particular. miR-31 maps to the intronic sequence of a novel long non-coding (lncRNA, LOC554202 and the regulation of its transcriptional activity is under control of LOC554202. Both miR-31 and the host gene LOC554202 are down-regulated in the TNBC cell lines of basal subtype and over-expressed in the luminal counterparts. Treatment of the TNBC cell lines with either a de-methylating agent alone or in combination with a de-acetylating agent resulted in a significant increase of both miR-31 and its host gene, suggesting an epigenetic mechanism for the silencing of these two genes by promoter hypermethylation. Finally, both methylation-specific PCR and sequencing of bisulfite-converted DNA demonstrated that the LOC554202 promoter-associated CpG island is heavily methylated in the TNBC cell lines and hypomethylated in the luminal subtypes. Conclusion Loss of miR-31 expression in TNBC cell lines is

First functional polymorphism in CFTR promoter that results in decreased transcriptional activity and Sp1/USF binding

International Nuclear Information System (INIS)

Taulan, M.; Lopez, E.; Guittard, C.; Rene, C.; Baux, D.; Altieri, J.P.; DesGeorges, M.; Claustres, M.; Romey, M.C.

2007-01-01

Growing evidences show that functionally relevant polymorphisms in various promoters alter both transcriptional activity and affinities of existing protein-DNA interactions, and thus influence disease progression in humans. We previously reported the -94G>T CFTR promoter variant in a female CF patient in whom any known disease-causing mutation has been detected. To investigate whether the -94G>T could be a regulatory variant, we have proceeded to in silico analyses and functional studies including EMSA and reporter gene assays. Our data indicate that the promoter variant decreases basal CFTR transcriptional activity in different epithelial cells and alters binding affinities of both Sp1 and USF nuclear proteins to the CFTR promoter. The present report provides evidence for the first functional polymorphism that negatively affects the CFTR transcriptional activity and demonstrates a cooperative role of Sp1 and USF transcription factors in transactivation of the CFTR gene promoter

Selective AR Modulators that Distinguish Proliferative from Differentiative Gene Promoters

Science.gov (United States)

2016-08-01

levels, and in some cases be useful in early stage disease or watchful waiting, and in other cases castration resistant prostate cancer (CRPC...dependent kinase inhibitor p21 gene through an androgen response element in the proximal promoter. Molecular endocrinology 13, 376 (Mar, 1999). 9...analyses and in mouse xenograft experiments, as planned. We will also continue to probe the molecular mechanism by which dox elicits these differential

Mapping of cis-regulatory sites in the promoter of testis-specific stellate genes of Drosophila melanogaster.

Science.gov (United States)

Olenkina, O M; Egorova, K S; Aravin, A A; Naumova, N M; Gvozdev, V A; Olenina, L V

2012-11-01

Tandem Stellate genes organized into two clusters in heterochromatin and euchromatin of the X-chromosome are part of the Ste-Su(Ste) genetic system required for maintenance of male fertility and reproduction of Drosophila melanogaster. Stellate genes encode a regulatory subunit of protein kinase CK2 and are the main targets of germline-specific piRNA-silencing; their derepression leads to appearance of protein crystals in spermatocytes, meiotic disturbances, and male sterility. A short promoter region of 134 bp appears to be sufficient for testis-specific transcription of Stellate, and it contains three closely located cis-regulatory elements called E-boxes. By using reporter analysis, we confirmed a strong functionality of the E-boxes in the Stellate promoter for in vivo transcription. Using selective mutagenesis, we have shown that the presence of the central E-box 2 is preferable to maintain a high-level testis-specific transcription of the reporter gene under the Stellate promoter. The Stellate promoter provides transcription even in heterochromatin, and corresponding mRNAs are translated with the generation of full-size protein products in case of disturbances in the piRNA-silencing process. We have also shown for the first time that the activity of the Stellate promoter is determined by chromatin context of the X-chromosome in male germinal cells, and it increases at about twofold when relocating in autosomes.

Analysis of tandem repeat units of the promoter of capsanthin/capsorubin synthase (Ccs) gene in pepper fruit.

Science.gov (United States)

Tian, Shi-Lin; Li, Zheng; Li, Li; Shah, S N M; Gong, Zhen-Hui

2017-07-01

Capsanthin/capsorubin synthase ( Ccs ) gene is a key gene that regulates the synthesis of capsanthin and the development of red coloration in pepper fruits. There are three tandem repeat units in the promoter region of Ccs , but the potential effects of the number of repetitive units on the transcriptional regulation of Ccs has been unclear. In the present study, expression vectors carrying different numbers of repeat units of the Ccs promoter were constructed, and the transient expression of the β-glucuronidase ( GUS ) gene was used to detect differences in expression levels associated with the promoter fragments. These repeat fragments and the plant expression vector PBI121 containing the 35s CaMV promoter were ligated to form recombinant vectors that were transfected into Agrobacterium tumefaciens GV3101. A fluorescence spectrophotometer was used to analyze the expression associated with the various repeat units. It was concluded that the constructs containing at least one repeat were associated with GUS expression, though they did not differ from one another. This repeating unit likely plays a role in transcription and regulation of Ccs expression.

ADAM33 gene silencing by promoter hypermethylation as a molecular marker in breast invasive lobular carcinoma

Directory of Open Access Journals (Sweden)

de Souza Emanuel M

2009-03-01

Full Text Available Abstract Background ADAM33 protein is a member of the family of transmembrane glycoproteins composed of multidomains. ADAM family members have different activities, such as proteolysis and adhesion, making them good candidates to mediate the extracellular matrix remodelling and changes in cellular adhesion that characterise certain pathologies and cancer development. It was reported that one family member, ADAM23, is down-regulated by promoter hypermethylation. This seems to correlate with tumour progression and metastasis in breast cancer. In this study, we explored the involvement of ADAM33, another ADAM family member, in breast cancer. Methods First, we analysed ADAM33 expression in breast tumour cell lines by RT-PCR and western blotting. We also used 5-aza-2'-deoxycytidine (5azadCR treatment and DNA bisulphite sequencing to study the promoter methylation of ADAM33 in breast tumour cell lines. We evaluated ADAM33 methylation in primary tumour samples by methylation specific PCR (MSP. Finally, ADAM33 promoter hypermethylation was correlated with clinicopathological data using the chi-square test and Fisher's exact test. Results The expression analysis of ADAM33 in breast tumour cell lines by RT-PCR revealed gene silencing in 65% of tumour cell lines. The corresponding lack of ADAM33 protein was confirmed by western blotting. We also used 5-aza-2'-deoxycytidine (5-aza-dCR demethylation and bisulphite sequencing methodologies to confirm that gene silencing is due to ADAM33 promoter hypermethylation. Using MSP, we detected ADAM33 promoter hypermethylation in 40% of primary breast tumour samples. The correlation between methylation pattern and patient's clinicopathological data was not significantly associated with histological grade; tumour stage (TNM; tumour size; ER, PR or ERBB2 status; lymph node status; metastasis or recurrence. Methylation frequency in invasive lobular carcinoma (ILC was 76.2% compared with 25.5% in invasive ductal carcinoma

Characterization and regulation of the bovine stearoyl-CoA desaturase gene promoter

International Nuclear Information System (INIS)

Keating, Aileen F.; Kennelly, John J.; Zhao Fengqi

2006-01-01

The bovine stearoyl-CoA desaturase (Scd) gene plays an important role in the bovine mammary gland where substrates such as stearic and vaccenic acids are converted to oleic acid and conjugated linoleic acid (CLA), respectively. Up to 90% of the CLA in bovine milk is formed due to the action of this enzyme in the mammary gland. The areas of the bovine promoter of importance in regulating this key enzyme were examined and an area of 36 bp in length was identified as having a critical role in transcriptional activation and is designated the Scd transcriptional enhancer element (STE). Electrophoretic mobility shift assay detected three binding complexes on this area in Mac-T cell nuclear extracts. Treatment of cells with CLA caused a significant reduction in transcriptional activity, with this effect being mediated through the STE region. The bovine Scd gene promoter was up-regulated by insulin and down-regulated by oleic acid

Overexpression of HMGA2-LPP fusion transcripts promotes expression of the α 2 type XI collagen gene

International Nuclear Information System (INIS)

Kubo, Takahiro; Matsui, Yoshito; Goto, Tomohiro; Yukata, Kiminori; Yasui, Natsuo

2006-01-01

In a subset of human lipomas, a specific t (3; 12) chromosome translocation gives rise to HMGA2-LPP fusion protein, containing the amino (N)-terminal DNA binding domains of HMGA2 fused to the carboxyl (C)-terminal LIM domains of LPP. In addition to its role in adipogenesis, several observations suggest that HMGA2-LPP is linked to chondrogenesis. Here, we analyzed whether HMGA2-LPP promotes chondrogenic differentiation, a marker of which is transactivation of the α 2 type XI collagen gene (Col11a2). Real-time PCR analysis showed that HMGA2-LPP and COL11A2 were co-expressed. Luciferase assay demonstrated that either of HMGA2-LPP, wild-type HMGA2 or the N-terminal HMGA2 transactivated the Col11a2 promoter in HeLa cells, while the C-terminal LPP did not. RT-PCR analysis revealed that HMGA2-LPP transcripts in lipomas with the fusion were 591-fold of full-length HMGA2 transcripts in lipomas without the fusion. These results indicate that in vivo overexpression of HMGA2-LPP promotes chondrogenesis by upregulating cartilage-specific collagen gene expression through the N-terminal DNA binding domains

Radioprotective effect of hematopoietic growth factor gene therapy regulated by Egr-1 promoter on radiation injury of SCID mice

International Nuclear Information System (INIS)

Du Nan; Pei Xuetao; Luo Chengji; Su Yongping; Cheng Tianmin

2002-01-01

Objective: To explore the radioprotective effect of the expression of hematopoietic growth factors regulated by radio-inducible promoter on radiation injury. Methods: The human FL cDNA and EGFP cDNA were linked together with an internal ribosome entry site (IRES) and then inserted into the eukaryotic expression vector pCI-neo with the Egr-1 promoter (Egr-EF), and further transduced into bone marrow stromal cell lines HFCL (HFCL/EF). The HFCL/EF and CD34 + cells from human umbilical cord blood were transplanted i.v. one after the other into sublethally irradiated severe combined immunodeficient (SCID) mice. The number of peripheral blood WBC and human cells engrafted in recipient mice were detected by flow cytometry and CFU-GM assay. Results: In contrast to two control groups (HFCL and HFCL/F), HFCL/EF (the Egr-1 regulatory element-driven expression of FL gene therapy) resulted in a proportionally obvious increase in the number of the WBC at early stage after irradiation. Significant differences were found for CD45 + , CD34 + , CFU-GM, and nucleated cells in the bone marrow. Conclusion: Hematopoietic growth factor gene therapy regulated by radio-inducible promoter has radioprotective effect on radiation hematopoietic injury

Role of an ER stress response element in regulating the bidirectional promoter of the mouse CRELD2 - ALG12 gene pair

Directory of Open Access Journals (Sweden)

Hirata Yoko

2010-11-01

Full Text Available Abstract Background Recently, we identified cysteine-rich with EGF-like domains 2 (CRELD2 as a novel endoplasmic reticulum (ER stress-inducible gene and characterized its transcriptional regulation by ATF6 under ER stress conditions. Interestingly, the CRELD2 and asparagine-linked glycosylation 12 homolog (ALG12 genes are arranged as a bidirectional (head-to-head gene pair and are separated by less than 400 bp. In this study, we characterized the transcriptional regulation of the mouse CRELD2 and ALG12 genes that is mediated by a common bidirectional promoter. Results This short intergenic region contains an ER stress response element (ERSE sequence and is well conserved among the human, rat and mouse genomes. Microarray analysis revealed that CRELD2 and ALG12 mRNAs were induced in Neuro2a cells by treatment with thapsigargin (Tg, an ER stress inducer, in a time-dependent manner. Other ER stress inducers, tunicamycin and brefeldin A, also increased the expression of these two mRNAs in Neuro2a cells. We then tested for the possible involvement of the ERSE motif and other regulatory sites of the intergenic region in the transcriptional regulation of the mouse CRELD2 and ALG12 genes by using variants of the bidirectional reporter construct. With regards to the promoter activities of the CRELD2-ALG12 gene pair, the entire intergenic region hardly responded to Tg, whereas the CRELD2 promoter constructs of the proximal region containing the ERSE motif showed a marked responsiveness to Tg. The same ERSE motif of ALG12 gene in the opposite direction was less responsive to Tg. The direction and the distance of this motif from each transcriptional start site, however, has no impact on the responsiveness of either gene to Tg treatment. Additionally, we found three putative sequences in the intergenic region that antagonize the ERSE-mediated transcriptional activation. Conclusions These results show that the mouse CRELD2 and ALG12 genes are arranged as a

Promoter Methylation and mRNA Expression of Response Gene to Complement 32 in Breast Carcinoma

International Nuclear Information System (INIS)

Nasab, E. E.; Nasab, E. E.; Hashemi, M.; Rafighdoost, F.

2016-01-01

Response gene to complement 32 (RGC32), induced by activation of complements, has been characterized as a cell cycle regulator; however, its role in carcinogenesis is still controversial. In the present study we compared RGC32 promoter methylation patterns and mRNA expression in breast cancerous tissues and adjacent normal tissues. Materials and Methods. Sixty-three breast cancer tissues and 63 adjacent non neoplastic tissues were included in our study. Design. Nested methylation-specific polymerase chain reaction (Nested-MSP) and quantitative PCR (qPCR) were used to determine RGC32 promoter methylation status and its mRNA expression levels, respectively. Results. RGC32 methylation pattern was not different between breast cancerous tissue and adjacent non neoplastic tissue (OR=2.30, 95% CI=0.95-5.54). However, qPCR analysis displayed higher levels of RGC32 mRNA in breast cancerous tissues than in noncancerous tissues (1.073 versus 0.959; P=0.001), irrespective of the promoter methylation status. The expression levels and promoter methylation of RGC32 were not correlated with any of patients’ clinical characteristics (P>0.05).

Cloning and characterization of largemouth bass ( Micropterus salmoides) myostatin encoding gene and its promoter

Science.gov (United States)

Li, Shengjie; Bai, Junjie; Wang, Lin

2008-08-01

Myostatin or GDF-8, a member of the transforming growth factor-β (TGF-β) superfamily, has been demonstrated to be a negative regulator of skeletal muscle mass in mammals. In the present study, we obtained a 5.64 kb sequence of myostatin encoding gene and its promoter from largemouth bass ( Micropterus salmoides). The myostatin encoding gene consisted of three exons (488 bp, 371 bp and 1779 bp, respectively) and two introns (390 bp and 855 bp, respectively). The intron-exon boundaries were conservative in comparison with those of mammalian myostatin encoding genes, whereas the size of introns was smaller than that of mammals. Sequence analysis of 1.569 kb of the largemouth bass myostatin gene promoter region revealed that it contained two TATA boxes, one CAAT box and nine putative E-boxes. Putative muscle growth response elements for myocyte enhancer factor 2 (MEF2), serum response factor (SRF), activator protein 1 (AP1), etc., and muscle-specific Mt binding site (MTBF) were also detected. Some of the transcription factor binding sites were conserved among five teleost species. This information will be useful for studying the transcriptional regulation of myostatin in fish.

Structure of the gene for human β2-adrenergic receptor: expression and promoter characterization

International Nuclear Information System (INIS)

Emorine, L.J.; Marullo, S.; Delavier-Klutchko, C.; Kaveri, S.V.; Durieu-Trautmann, O.; Strosberg, A.D.

1987-01-01

The genomic gene coding for the human β 2 -adrenergic receptor (β 2 AR) from A431 epidermoid cells has been isolated. Transfection of the gene into eukaryotic cells restores a fully active receptor/GTP-binding protein/adenylate cyclase complex with β 2 AR properties. Southern blot analyses with β 2 AR-specific probes show that a single β 2 AR gene is common to various human tissues and that its flanking sequences are highly conserved among humans and between man and rabbit, mouse, and hamster. Functional significance of these regions is supported by the presence of a promoter region (including mRNA cap sites, two TATA boxes, a CAAT box, and three G + C-rich regions that resemble binding sites for transcription factor Sp1) 200-300 base pairs 5' to the translation initiation codon. In the 3' flanking region, sequences homologous to glucocorticoid-response elements might be responsible for the increased expression of the β 2 AR gene observed after treatment of the transfected cells with hydrocortisone. In addition, 5' to the promoter region, an open reading frame encodes a 251-residue polypeptide that displays striking homologies with protein kinases and other nucleotide-binding proteins

Codon 61 mutations in the c-Harvey-ras gene in mouse skin tumors induced by 7,12-dimethylbenz[a]anthracene plus okadaic acid class tumor promoters.

Science.gov (United States)

Fujiki, H; Suganuma, M; Yoshizawa, S; Kanazawa, H; Sugimura, T; Manam, S; Kahn, S M; Jiang, W; Hoshina, S; Weinstein, I B

1989-01-01

Three okadaic acid class tumor promoters, okadaic acid, dinophysistoxin-1, and calyculin A, have potent tumor-promoting activity in two-stage carcinogenesis experiments on mouse skin. DNA isolated from tumors induced by 7,12-dimethylbenz[a]anthracene (DMBA) and each of these tumor promoters revealed the same mutation at the second nucleotide of codon 61 (CAA----CTA) in the c-Ha-ras gene, determined by the polymerase chain reaction procedure and DNA sequencing. Three potent 12-O-tetradecanoylphorbol-13-acetate (TPA)-type tumor promoters, TPA, teleocidin, and aplysiatoxin, showed the same effects. These results provide strong evidence that this mutation in the c-Ha-ras gene is due to a direct effect of DMBA rather than a selective effect of specific tumor promoters.

Glucose metabolism in pigs expressing human genes under an insulin promoter.

Science.gov (United States)

Wijkstrom, Martin; Bottino, Rita; Iwase, Hayoto; Hara, Hidetaka; Ekser, Burcin; van der Windt, Dirk; Long, Cassandra; Toledo, Frederico G S; Phelps, Carol J; Trucco, Massimo; Cooper, David K C; Ayares, David

2015-01-01

Xenotransplantation of porcine islets can reverse diabetes in non-human primates. The remaining hurdles for clinical application include safe and effective T-cell-directed immunosuppression, but protection against the innate immune system and coagulation dysfunction may be more difficult to achieve. Islet-targeted genetic manipulation of islet-source pigs represents a powerful tool to protect against graft loss. However, whether these genetic alterations would impair islet function is unknown. On a background of α1,3-galactosyltransferase gene-knockout (GTKO)/human (h)CD46, additional genes (hCD39, human tissue factor pathway inhibitor, porcine CTLA4-Ig) were inserted in different combinations under an insulin promoter to promote expression in islets (confirmed by immunofluorescence). Seven pigs were tested for baseline and glucose/arginine-challenged levels of glucose, insulin, C-peptide, and glucagon. This preliminary study did not show definite evidence of β-cell deficiencies, even when three transgenes were expressed under the insulin promoter. Of seven animals, all were normoglycemic at fasting, and five of seven had normal glucose disposal rates after challenge. All animals exhibited insulin, C-peptide, and glucagon responses to both glucose and arginine challenge; however, significant interindividual variation was observed. Multiple islet-targeted transgenic expression was not associated with an overtly detrimental effect on islet function, suggesting that complex genetic constructs designed for islet protection warrants further testing in islet xenotransplantation models. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

USP7 Attenuates Hepatic Gluconeogenesis Through Modulation of FoxO1 Gene Promoter Occupancy

Science.gov (United States)

Hall, Jessica A.; Tabata, Mitsuhisa; Rodgers, Joseph T.

2014-01-01

Hepatic forkhead protein FoxO1 is a key component of systemic glucose homeostasis via its ability to regulate the transcription of rate-limiting enzymes in gluconeogenesis. Important in the regulation of FoxO1 transcriptional activity are the modifying/demodifying enzymes that lead to posttranslational modification. Here, we demonstrate the functional interaction and regulation of FoxO1 by herpesvirus-associated ubiquitin-specific protease 7 (USP7; also known as herpesvirus-associated ubiquitin-specific protease, HAUSP), a deubiquitinating enzyme. We show that USP7-mediated mono-deubiquitination of FoxO1 results in suppression of FoxO1 transcriptional activity through decreased FoxO1 occupancy on the promoters of gluconeogenic genes. Knockdown of USP7 in primary hepatocytes leads to increased expression of FoxO1-target gluconeogenic genes and elevated glucose production. Consistent with this, USP7 gain-of-function suppresses the fasting/cAMP-induced activation of gluconeogenic genes in hepatocyte cells and in mouse liver, resulting in decreased hepatic glucose production. Notably, we show that the effects of USP7 on hepatic glucose metabolism depend on FoxO1. Together, these results place FoxO1 under the intimate regulation of deubiquitination and glucose metabolic control with important implication in diseases such as diabetes. PMID:24694308

Urinary retinoic acid receptor-β2 gene promoter methylation and hyaluronidase activity as noninvasive tests for diagnosis of bladder cancer.

Science.gov (United States)

Eissa, Sanaa; Zohny, Samir F; Shehata, Hanan Hussien; Hegazy, Marwa G A; Salem, Ahmed M; Esmat, Mohamed

2012-04-01

We evaluated the significance of urinary retinoic acid receptor-β2 (RAR-β2) gene promoter methylation and hyaluronidase activity in comparison with voided urine cytology (VUC) in diagnosis of bladder cancer. This study included 100 patients diagnosed with bladder cancer, 65 patients with benign urological disorders and 51 healthy volunteers. Urine supernatant was used for determining hyaluronidase activity by zymography while urine sediment was used for cytology and detection of methylated RAR-β2 gene promoter by methylation specific nested PCR. The sensitivity and specificity were 53% and 90.5% for VUC, 65% and 89.7% for percent methylation fraction of RAR-β2 gene promoter, and 89% and 90.5% for hyaluronidase activity; combination of the three parameters increased sensitivity to 95%. A significant association was observed between investigated markers and advanced grade tumor. Combined use of RAR-β2 gene promoter methylation, hyaluronidase activity and VUC is promising non-invasive tool for bladder cancer detection. Copyright © 2012. Published by Elsevier Inc.

IL6 gene promoter polymorphisms and type 2 diabetes

DEFF Research Database (Denmark)

Huth, Cornelia; Heid, Iris M; Vollmert, Caren

2006-01-01

Several lines of evidence indicate a causal role of the cytokine interleukin (IL)-6 in the development of type 2 diabetes in humans. Two common polymorphisms in the promoter of the IL-6 encoding gene IL6, -174G>C (rs1800795) and -573G>C (rs1800796), have been investigated for association with type...... 2 diabetes in numerous studies but with results that have been largely equivocal. To clarify the relationship between the two IL6 variants and type 2 diabetes, we analyzed individual data on >20,000 participants from 21 published and unpublished studies. Collected data represent eight different...... countries, making this the largest association analysis for type 2 diabetes reported to date. The GC and CC genotypes of IL6 -174G>C were associated with a decreased risk of type 2 diabetes (odds ratio 0.91, P = 0.037), corresponding to a risk modification of nearly 9%. No evidence for association was found...

Epigenetic Alteration by DNA Promoter Hypermethylation of Genes Related to Transforming Growth Factor-β (TGF-β) Signaling in Cancer

Energy Technology Data Exchange (ETDEWEB)

Khin, Sann Sanda [Kobe University Graduate School of Medicine, Division of Diagnostic Molecular Pathology, Kobe 650-0017 (Japan); Pathology Research Unit, Department of Medical Research (Central Myanmar), Naypyitaw, Union of (Myanmar); Kitazawa, Riko [Kobe University Graduate School of Medicine, Division of Diagnostic Molecular Pathology, Kobe 650-0017 (Japan); Ehime University Graduate School of Medicine, Toon 791-0295, Ehime (Japan); Kondo, Takeshi; Idei, Yuka; Fujimoto, Masayo [Kobe University Graduate School of Medicine, Division of Diagnostic Molecular Pathology, Kobe 650-0017 (Japan); Haraguchi, Ryuma [Ehime University Graduate School of Medicine, Toon 791-0295, Ehime (Japan); Mori, Kiyoshi [Kobe University Graduate School of Medicine, Division of Diagnostic Molecular Pathology, Kobe 650-0017 (Japan); Kitazawa, Sohei, E-mail: kitazawa@m.ehime-u.ac.jp [Kobe University Graduate School of Medicine, Division of Diagnostic Molecular Pathology, Kobe 650-0017 (Japan); Ehime University Graduate School of Medicine, Toon 791-0295, Ehime (Japan)

2011-03-03

Epigenetic alterations in cancer, especially DNA methylation and histone modification, exert a significant effect on the deregulated expression of cancer-related genes and lay an epigenetic pathway to carcinogenesis and tumor progression. Global hypomethylation and local hypermethylation of CpG islands in the promoter region, which result in silencing tumor suppressor genes, constitute general and major epigenetic modification, the hallmark of the neoplastic epigenome. Additionally, methylation-induced gene silencing commonly affects a number of genes and increases with cancer progression. Indeed, cancers with a high degree of methylation (CpG island methylator phenotype/CIMP) do exist and represent a distinct subset of certain cancers including colorectal, bladder and kidney. On the other hand, signals from the microenvironment, especially those from transforming growth factor-β (TGF-β), induce targeted de novo epigenetic alterations of cancer-related genes. While TGF-β signaling has been implicated in two opposite roles in cancer, namely tumor suppression and tumor promotion, its deregulation is also partly induced by epigenetic alteration itself. Although the epigenetic pathway to carcinogenesis and cancer progression has such reciprocal complexity, the important issue is to identify genes or signaling pathways that are commonly silenced in various cancers in order to find early diagnostic and therapeutic targets. In this review, we focus on the epigenetic alteration by DNA methylation and its role in molecular modulations of the TGF-β signaling pathway that cause or underlie altered cancer-related gene expression in both phases of early carcinogenesis and late cancer progression.

Epigenetic Alteration by DNA Promoter Hypermethylation of Genes Related to Transforming Growth Factor-β (TGF-β) Signaling in Cancer

International Nuclear Information System (INIS)

Khin, Sann Sanda; Kitazawa, Riko; Kondo, Takeshi; Idei, Yuka; Fujimoto, Masayo; Haraguchi, Ryuma; Mori, Kiyoshi; Kitazawa, Sohei

2011-01-01

Epigenetic alterations in cancer, especially DNA methylation and histone modification, exert a significant effect on the deregulated expression of cancer-related genes and lay an epigenetic pathway to carcinogenesis and tumor progression. Global hypomethylation and local hypermethylation of CpG islands in the promoter region, which result in silencing tumor suppressor genes, constitute general and major epigenetic modification, the hallmark of the neoplastic epigenome. Additionally, methylation-induced gene silencing commonly affects a number of genes and increases with cancer progression. Indeed, cancers with a high degree of methylation (CpG island methylator phenotype/CIMP) do exist and represent a distinct subset of certain cancers including colorectal, bladder and kidney. On the other hand, signals from the microenvironment, especially those from transforming growth factor-β (TGF-β), induce targeted de novo epigenetic alterations of cancer-related genes. While TGF-β signaling has been implicated in two opposite roles in cancer, namely tumor suppression and tumor promotion, its deregulation is also partly induced by epigenetic alteration itself. Although the epigenetic pathway to carcinogenesis and cancer progression has such reciprocal complexity, the important issue is to identify genes or signaling pathways that are commonly silenced in various cancers in order to find early diagnostic and therapeutic targets. In this review, we focus on the epigenetic alteration by DNA methylation and its role in molecular modulations of the TGF-β signaling pathway that cause or underlie altered cancer-related gene expression in both phases of early carcinogenesis and late cancer progression

The Helicobacter pylori duodenal ulcer promoting gene, dupA in China

Directory of Open Access Journals (Sweden)

Liu Wenzhong

2008-10-01

Full Text Available Abstract Background The prevalence of H. pylori is as high as 60–70% in Chinese population. Although duodenal ulcer and gastric cancer are both caused by H. pylori, they are at opposite ends of the spectrum and as such are considered mutually exclusive. Duodenal ulcer promoting (dupA gene was reported to be associated with duodenal ulcer development. The aim of this study was to determine the prevalence of dupA gene of Helicobacter pylori in patients with various gastroduodenal diseases and to explore the association between the gene and other virulence factors. Methods H. pylori were isolated from gastric biopsies of patients with chronic gastritis, duodenal ulcer (DU, gastric ulcer (GU, or non-cardia gastric carcinoma. The dupA, cagA, vacA, iceA and babA2 genotypes were determined by polymerase chain reaction. Histological features of gastric mucosal biopsy specimens were graded based on the scoring system proposed by the updated Sydney system. IL-1β polymorphism was investigated using restriction fragment length polymorphism. Results Isolates from 360 patients including 133 with chronic gastritis, 101 with DU, 47 with GU, and 79 with non-cardia gastric carcinoma were examined. The dupA gene was detected in 35.3% (127/360 and the prevalence DU patients was significantly greater than that in gastric cancer or GU patients (45.5% vs. 24.1% and 23.4%, P dupA-positive strains had higher scores for chronic inflammation compared to those with dupA-negative strains (2.36 vs. 2.24, p = 0.058. The presence of dupA was not associated with the cagA, vacA, iceA and babA 2 genotypes or with IL-1β polymorphisms. Conclusion In China the prevalence of dupA gene was highest in DU and inversely related to GU and gastric cancer.

Evaluation of Results from Sales Promotion Activities

Directory of Open Access Journals (Sweden)

Olimpia Ban

2007-02-01

Full Text Available An essential element of the sales promotion strategy and not only is the evaluation of the results obtained from the activities performed. Due to their nature and applicability, the evaluation of the sales promotion is much easier to be achieved, but it raises some problems. Using a hypothetical example, we have tried to develop a "classic" evaluation model of the specialty literature.

AMPK activation represses the human gene promoter of the cardiac isoform of acetyl-CoA carboxylase: Role of nuclear respiratory factor-1

Energy Technology Data Exchange (ETDEWEB)

Adam, Tasneem; Opie, Lionel H. [Hatter Cardiovascular Research Institute, Faculty of Health Sciences, University of Cape Town, Observatory 7925 (South Africa); Essop, M. Faadiel, E-mail: mfessop@sun.ac.za [Cardio-Metabolic Research Group (CMRG), Department of Physiological Sciences, Stellenbosch University, Stellenbosch 7600 (South Africa)

2010-07-30

Research highlights: {yields} AMPK inhibits acetyl-CoA carboxylase beta gene promoter activity. {yields} Nuclear respiratory factor-1 inhibits acetyl-CoA carboxylase beta promoter activity. {yields} AMPK regulates acetyl-CoA carboxylase beta at transcriptional level. -- Abstract: The cardiac-enriched isoform of acetyl-CoA carboxylase (ACC{beta}) produces malonyl-CoA, a potent inhibitor of carnitine palmitoyltransferase-1. AMPK inhibits ACC{beta} activity, lowering malonyl-CoA levels and promoting mitochondrial fatty acid {beta}-oxidation. Previously, AMPK increased promoter binding of nuclear respiratory factor-1 (NRF-1), a pivotal transcriptional modulator controlling gene expression of mitochondrial proteins. We therefore hypothesized that NRF-1 inhibits myocardial ACC{beta} promoter activity via AMPK activation. A human ACC{beta} promoter-luciferase construct was transiently transfected into neonatal cardiomyocytes {+-} a NRF-1 expression construct. NRF-1 overexpression decreased ACC{beta} gene promoter activity by 71 {+-} 4.6% (p < 0.001 vs. control). Transfections with 5'-end serial promoter deletions revealed that NRF-1-mediated repression of ACC{beta} was abolished with a pPII{beta}-18/+65-Luc deletion construct. AMPK activation dose-dependently reduced ACC{beta} promoter activity, while NRF-1 addition did not further decrease it. We also investigated NRF-1 inhibition in the presence of upstream stimulatory factor 1 (USF1), a known transactivator of the human ACC{beta} gene promoter. Here NRF-1 blunted USF1-dependent induction of ACC{beta} promoter activity by 58 {+-} 7.5% (p < 0.001 vs. control), reversed with a dominant negative NRF-1 construct. NRF-1 also suppressed endogenous USF1 transcriptional activity by 55 {+-} 6.2% (p < 0.001 vs. control). This study demonstrates that NRF-1 is a novel transcriptional inhibitor of the human ACC{beta} gene promoter in the mammalian heart. Our data extends AMPK regulation of ACC{beta} to the transcriptional level.

Aquilegia B gene homologs promote petaloidy of the sepals and maintenance of the C domain boundary

Directory of Open Access Journals (Sweden)

Bharti Sharma

2017-11-01

Full Text Available Abstract The model Aquilegia coerulea x “Origami” possesses several interesting floral features, including petaloid sepals that are morphologically distinct from the true petals and a broad domain containing many whorls of stamens. We undertook the current study in an effort to understand the former trait, but additionally uncovered data that inform on the latter. The Aquilegia B gene homolog AqPI is shown to contribute to the production of anthocyanin in the first whorl sepals, although it has no major role in their morphology. Surprisingly, knockdown of AqPI in Aquilegia coerulea x “Origami” also reveals a role for the B class genes in maintaining the expression of the C gene homolog AqAG1 in the outer whorls of stamens. These findings suggest that the transference of pollinator function to the first whorl sepals included a non-homeotic recruitment of the B class genes to promote aspects of petaloidy. They also confirm results in several other Ranunculales that have revealed an unexpected regulatory connection between the B and C class genes.

Direct interactions of OCA-B and TFII-I regulate immunoglobulin heavy-chain gene transcription by facilitating enhancer-promoter communication.

Science.gov (United States)

Ren, Xiaodi; Siegel, Rachael; Kim, Unkyu; Roeder, Robert G

2011-05-06

B cell-specific coactivator OCA-B, together with Oct-1/2, binds to octamer sites in promoters and enhancers to activate transcription of immunoglobulin (Ig) genes, although the mechanisms underlying their roles in enhancer-promoter communication are unknown. Here, we demonstrate a direct interaction of OCA-B with transcription factor TFII-I, which binds to DICE elements in Igh promoters, that affects transcription at two levels. First, OCA-B relieves HDAC3-mediated Igh promoter repression by competing with HDAC3 for binding to promoter-bound TFII-I. Second, and most importantly, Igh 3' enhancer-bound OCA-B and promoter-bound TFII-I mediate promoter-enhancer interactions, in both cis and trans, that are important for Igh transcription. These and other results reveal an important function for OCA-B in Igh 3' enhancer function in vivo and strongly favor an enhancer mechanism involving looping and facilitated factor recruitment rather than a tracking mechanism. Copyright © 2011 Elsevier Inc. All rights reserved.

Molecular Characterization of SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL Gene Family in Betula luminifera

Directory of Open Access Journals (Sweden)

Xiu-Yun Li

2018-05-01

Full Text Available As a major family of plant-specific transcription factors, SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL genes play vital regulatory roles in plant growth, development and stress responses. In this study, 18 SPL genes were identified and cloned from Betula luminifera. Two zinc finger-like structures and a nuclear location signal (NLS segments were existed in the SBP domains of all BlSPLs. Phylogenetic analysis showed that these genes were clustered into nine groups (group I-IX. The intron/exon structure and motif composition were highly conserved within the same group. 12 of the 18 BlSPLs were experimentally verified as the targets of miR156, and two cleavage sites were detected in these miR156-targeted BlSPL genes. Many putative cis-elements, associated with light, stresses and phytohormones response, were identified in the promoter regions of BlSPLs, suggesting that BlSPL genes are probably involved in important physiological processes and developmental events. Tissue-specific expression analysis showed that miR156-targeted BlSPLs exhibited a more differential expression pattern, while most miR156-nontargeted BlSPLs tended to be constitutively expressed, suggesting the distinct roles of miR156-targeted and nontargeted BlSPLs in development and growth of B. luminifera. Further expression analysis revealed that miR156-targeted BlSPLs were dramatically up-regulated with age, whereas mature BlmiR156 level was apparently declined with age, indicating that miR156/SPL module plays important roles in vegetative phase change of B. luminifera. Moreover, yeast two-hybrid assay indicated that several miR156-targeted and nontargeted BlSPLs could interact with two DELLA proteins (BlRGA and BlRGL, which suggests that certain BlSPLs take part in the GA regulated processes through protein interaction with DELLA proteins. All these results provide an important basis for further exploring the biological functions of BlSPLs in B. luminifera.

Nonsense and missense mutation of mitochondrial ND6 gene promotes cell migration and invasion in human lung adenocarcinoma

International Nuclear Information System (INIS)

Yuan, Yang; Wang, Weixing; Li, Huizhong; Yu, Yongwei; Tao, Jin; Huang, Shengdong; Zeng, Zhiyong

2015-01-01

Previous study showed that mitochondrial ND6 (mitND6) gene missense mutation resulted in NADH dehydrogenase deficiency and was associated with tumor metastasis in several mouse tumor cell lines. In the present study, we investigated the possible role of mitND6 gene nonsense and missense mutations in the metastasis of human lung adenocarcinoma. The presence of mitND6 gene mutations was screened by DNA sequencing of tumor tissues from 87 primary lung adenocarcinoma patients and the correlation of the mutations with the clinical features was analyzed. In addition, we constructed cytoplasmic hybrid cells with denucleared primary lung adenocarcinoma cell as the mitochondria donor and mitochondria depleted lung adenocarcinoma A549 cell as the nuclear donor. Using these cells, we studied the effects of mitND6 gene nonsense and missense mutations on cell migration and invasion through wounding healing and matrigel-coated transwell assay. The effects of mitND6 gene mutations on NADH dehydrogenase activity and ROS production were analyzed by spectrophotometry and flow cytometry. mitND6 gene nonsense and missense mutations were detected in 11 of 87 lung adenocarcinoma specimens and was correlated with the clinical features including age, pathological grade, tumor stage, lymph node metastasis and survival rate. Moreover, A549 cell containing mitND6 gene nonsense and missense mutation exhibited significantly lower activity of NADH dehydrogenase, higher level of ROS, higher capacity of cell migration and invasion, and higher pAKT and pERK1/ERK2 expression level than cells with the wild type mitND6 gene. In addition, NADH dehydrogenase inhibitor rotenone was found to significantly promote the migration and invasion of A549 cells. Our data suggest that mitND6 gene nonsense and missense mutation might promote cell migration and invasion in lung adenocarcinoma, probably by NADH dehydrogenase deficiency induced over-production of ROS

A primary study of high performance transgenic rice through maize UBI-1 promoter fusing selective maker gene

International Nuclear Information System (INIS)

Shen, J.; Cai, P.; Qing, F.

2012-01-01

Based on the expression vector pBI121, we successfully constructed a plant over-expression vector of Hspa4 gene fusing with selective maker gene (hygromycin-resistance gene) driven by the Ubi-1 promoter (pBI121-Ubi-Hpt-Hspa4, p121UHH). The plant expression vectors p121UHH and pCAMBIA1301-Ubi-Hspa4 (p1301UH) were transformed into the rice callus, mediated by Agrobacterium tumefaciens. We screened 17 p121UHH-positive transgenic plants and 15 p1301UH-positive transgenic plants by the hygromycin-resistance gene. The pick-up rate of the resistance callus was 51.7% and 42.5%, respectively, and the rate of regeneration for the resistance callus was 51.2% and 49.1%, respectively. The result of polymerase chain reaction (P CR) identification indicated that the pick-up rate of positive transgenic plants was 51.7% and 42.5% and the total transformation efficiency was 16.5% and 6.2%, and the former was 2.66 time s of the later. The results of the experiment indicate that the possibility of the appearance of false positive results in the fusing of a plant over-expression vector with a selective maker gene is much less. (author)

Genomic organization and promoter cloning of the human X11α gene APBA1.

LENUS (Irish Health Repository)

Chai, Ka-Ho

2012-05-01

X11α is a brain specific multi-modular protein that interacts with the Alzheimer\\'s disease amyloid precursor protein (APP). Aggregation of amyloid-β peptide (Aβ), an APP cleavage product, is believed to be central to the pathogenesis of Alzheimer\\'s disease. Recently, overexpression of X11α has been shown to reduce Aβ generation and to ameliorate memory deficit in a transgenic mouse model of Alzheimer\\'s disease. Therefore, manipulating the expression level of X11α may provide a novel route for the treatment of Alzheimer\\'s disease. Human X11α is encoded by the gene APBA1. As evidence suggests that X11α expression can be regulated at transcription level, we have determined the gene structure and cloned the promoter of APBA1. APBA1 spans over 244 kb on chromosome 9 and is composed of 13 exons and has multiple transcription start sites. A putative APBA1 promoter has been identified upstream of exon 1 and functional analysis revealed that this is highly active in neurons. By deletion analysis, the minimal promoter was found to be located between -224 and +14, a GC-rich region that contains a functional Sp3 binding site. In neurons, overexpression of Sp3 stimulates the APBA1 promoter while an Sp3 inhibitor suppresses the promoter activity. Moreover, inhibition of Sp3 reduces endogenous X11α expression and promotes the generation of Aβ. Our findings reveal that Sp3 play an essential role in APBA1 transcription.

A genome-wide analysis of promoter-mediated phenotypic noise in Escherichia coli.

Directory of Open Access Journals (Sweden)

Olin K Silander

2012-01-01

Full Text Available Gene expression is subject to random perturbations that lead to fluctuations in the rate of protein production. As a consequence, for any given protein, genetically identical organisms living in a constant environment will contain different amounts of that particular protein, resulting in different phenotypes. This phenomenon is known as "phenotypic noise." In bacterial systems, previous studies have shown that, for specific genes, both transcriptional and translational processes affect phenotypic noise. Here, we focus on how the promoter regions of genes affect noise and ask whether levels of promoter-mediated noise are correlated with genes' functional attributes, using data for over 60% of all promoters in Escherichia coli. We find that essential genes and genes with a high degree of evolutionary conservation have promoters that confer low levels of noise. We also find that the level of noise cannot be attributed to the evolutionary time that different genes have spent in the genome of E. coli. In contrast to previous results in eukaryotes, we find no association between promoter-mediated noise and gene expression plasticity. These results are consistent with the hypothesis that, in bacteria, natural selection can act to reduce gene expression noise and that some of this noise is controlled through the sequence of the promoter region alone.

ERalpha and AP-1 interact in vivo with a specific sequence of the F promoter of the human ERalpha gene in osteoblasts.

Science.gov (United States)

Lambertini, Elisabetta; Tavanti, Elisa; Torreggiani, Elena; Penolazzi, Letizia; Gambari, Roberto; Piva, Roberta

2008-07-01

Estrogen-responsive genes often have an estrogen response element (ERE) positioned next to activator protein-1 (AP-1) binding sites. Considering that the interaction between ERE and AP-1 elements has been described for the modulation of bone-specific genes, we investigated the 17-beta-estradiol responsiveness and the role of these cis-elements present in the F promoter of the human estrogen receptor alpha (ERalpha) gene. The F promoter, containing the sequence analyzed here, is one of the multiple promoters of the human ERalpha gene and is the only active promoter in bone tissue. Through electrophoretic mobility shift (EMSA), chromatin immunoprecipitation (ChIP), and re-ChIP assays, we investigated the binding of ERalpha and four members of the AP-1 family (c-Jun, c-fos, Fra-2, and ATF2) to a region located approximately 800 bp upstream of the transcriptional start site of exon F of the human ERalpha gene in SaOS-2 osteoblast-like cells. Reporter gene assay experiments in combination with DNA binding assays demonstrated that F promoter activity is under the control of upstream cis-acting elements which are recognized by specific combinations of ERalpha, c-Jun, c-fos, and ATF2 homo- and heterodimers. Moreover, ChIP and re-ChIP experiments showed that these nuclear factors bind the F promoter in vivo with a simultaneous occupancy stimulated by 17-beta-estradiol. Taken together, our findings support a model in which ERalpha/AP-1 complexes modulate F promoter activity under conditions of 17-beta-estradiol stimulation. (c) 2008 Wiley-Liss, Inc.

Genetic and Epigenetic Tumor Suppressor Gene Silencing Are Distinct Molecular Phenotypes Driven by Growth Promoting Mutations in Nonsmall Cell Lung Cancer

Directory of Open Access Journals (Sweden)

Carmen J. Marsit

2008-01-01

Full Text Available Both genetic and epigenetic alterations characterize human nonsmall cell lung cancer (NSCLC, but the biological processes that create or select these alterations remain incompletely investigated. Our hypothesis posits that a roughly reciprocal relationship between the propensity for promoter hypermethylation and a propensity for genetic deletion leads to distinct molecular phenotypes of lung cancer. To test this hypothesis, we examined promoter hypermethylation of 17 tumor suppressor genes, as a marker of epigenetic alteration propensity, and deletion events at the 3p21 region, as a marker of genetic alteration. To model the complex biology between these somatic alterations, we utilized an item response theory model. We demonstrated that tumors exhibiting LOH at greater than 30% of informative alleles in the 3p21 region have a significantly reduced propensity for hypermethylation. At the same time, tumors with activating KRAS mutations showed a significantly increased propensity for hypermethylation of the loci examined, a result similar to what has been observed in colon cancer. These data suggest that NSCLCs have distinct epigenetic or genetic alteration phenotypes acting upon tumor suppressor genes and that mutation of oncogenic growth promoting genes, such as KRAS, is associated with the epigenetic phenotype.

Live-cell Imaging of Pol II Promoter Activity to Monitor Gene expression with RNA IMAGEtag reporters

Energy Technology Data Exchange (ETDEWEB)

Shin, Ilchung [Ames Laboratory; Ray, Judhajeet [Ames Laboratory; Gupta, Vinayak [Iowa State University; Ilgu, Muslum [Ames Laboratory; Beasley, Jonathan [Iowa State University; Bendickson, Lee [Ames Laboratory; Mehanovic, Samir [Molecular Express; Kraus, George A. [Iowa State University; Nilsen-Hamilton, Marit [Ames Laboratory

2014-04-20

We describe a ribonucleic acid (RNA) reporter system for live-cell imaging of gene expression to detect changes in polymerase II activity on individual promoters in individual cells. The reporters use strings of RNA aptamers that constitute IMAGEtags (Intracellular MultiAptamer GEnetic tags) that can be expressed from a promoter of choice. For imaging, the cells are incubated with their ligands that are separately conjugated with one of the FRET pair, Cy3 and Cy5. The IMAGEtags were expressed in yeast from the GAL1, ADH1 or ACT1 promoters. Transcription from all three promoters was imaged in live cells and transcriptional increases from the GAL1 promoter were observed with time after adding galactose. Expression of the IMAGEtags did not affect cell proliferation or endogenous gene expression. Advantages of this method are that no foreign proteins are produced in the cells that could be toxic or otherwise influence the cellular response as they accumulate, the IMAGEtags are short lived and oxygen is not required to generate their signals. The IMAGEtag RNA reporter system provides a means of tracking changes in transcriptional activity in live cells and in real time.

Association between promoter polymorphisms of OPN gene and cancer risk: a meta-analysis

Directory of Open Access Journals (Sweden)

Liu JW

2015-12-01

Full Text Available Jingwei Liu,1–2 Caiyun He,1–2 Quan Yuan,1–2 Zhenning Wang,1–2 Chengzhong Xing,1–2 Yuan Yuan1–2 1Tumor Etiology and Screening Department of Cancer Institute and General Surgery, The First Affiliated Hospital of China Medical University, 2Key Laboratory of Cancer Etiology and Prevention, China Medical University, Liaoning Provincial Education Department, Shenyang, People’s Republic of China Background: Results of the association between polymorphisms of osteopontin (OPN gene promoter region and risk of cancer were inconclusive. The aim of this meta-analysis was to elucidate whether OPN promoter polymorphisms were associated with cancer risk.Methods: Electronic databases including PubMed, Web of Science, and Chinese National Knowledge Infrastructure were systematically searched. Odd ratios (ORs and their 95% confidential interval (CI were used to assess the strength of association between OPN promoter polymorphisms and cancer risks.Results: Nine studies were finally included in this meta-analysis. For OPN rs17524488 polymorphism, carriers of GG or -/G genotype were significantly associated with increased cancer risk compared with wild-type -/- carriers, respectively (GG vs -/-: OR =1.40, 95% CI =1.03–1.91, P=0.033; -/G vs -/-: OR =1.22, 95% CI =1.07–1.40, P=0.002. Additionally, G allele was significantly associated with increased cancer risk compared with (- allele (OR =1.21, 95% CI =1.04–1.40, P=0.016. However, no significant association was observed of OPN rs11730582 polymorphism and cancer risk (CC vs TT: OR =0.98, 95% CI =0.49–1.97, P=0.964; CT vs TT: OR =0.88, 95% CI =0.54–1.43, P=0.610.Conclusion: Carriers of GG or -/G genotype of OPN promoter rs17524488 (-156-/G polymorphism might be associated with increased risk of cancer compared with wild-type -/- carriers, respectively. However, no significant association was observed between OPN promoter rs11730582 (-443C/T polymorphism and risk of cancer. Keywords: OPN

Dynamic O-GlcNAc cycling at promoters of Caenorhabditis elegans genes regulating longevity, stress, and immunity.

Science.gov (United States)

Love, Dona C; Ghosh, Salil; Mondoux, Michelle A; Fukushige, Tetsunari; Wang, Peng; Wilson, Mark A; Iser, Wendy B; Wolkow, Catherine A; Krause, Michael W; Hanover, John A

2010-04-20

Nutrient-driven O-GlcNAcylation of key components of the transcription machinery may epigenetically modulate gene expression in metazoans. The global effects of GlcNAcylation on transcription can be addressed directly in C. elegans because knockouts of the O-GlcNAc cycling enzymes are viable and fertile. Using anti-O-GlcNAc ChIP-on-chip whole-genome tiling arrays on wild-type and mutant strains, we detected over 800 promoters where O-GlcNAc cycling occurs, including microRNA loci and multigene operons. Intriguingly, O-GlcNAc-marked promoters are biased toward genes associated with PIP3 signaling, hexosamine biosynthesis, and lipid/carbohydrate metabolism. These marked genes are linked to insulin-like signaling, metabolism, aging, stress, and pathogen-response pathways in C. elegans. Whole-genome transcriptional profiling of the O-GlcNAc cycling mutants confirmed dramatic deregulation of genes in these key pathways. As predicted, the O-GlcNAc cycling mutants show altered lifespan and UV stress susceptibility phenotypes. We propose that O-GlcNAc cycling at promoters participates in a molecular program impacting nutrient-responsive pathways in C. elegans, including stress, pathogen response, and adult lifespan. The observed impact of O-GlcNAc cycling on both signaling and transcription in C. elegans has important implications for human diseases of aging, including diabetes and neurodegeneration.

Regulatory polymorphisms in the bovine Ankyrin 1 gene promoter are associated with tenderness and intra-muscular fat content

LENUS (Irish Health Repository)

Aslan, Ozlem

2010-12-15

Abstract Background Recent QTL and gene expression studies have highlighted ankyrins as positional and functional candidate genes for meat quality. Our objective was to characterise the promoter region of the bovine ankyrin 1 gene and to test polymorphisms for association with sensory and technological meat quality measures. Results Seven novel promoter SNPs were identified in a 1.11 kb region of the ankyrin 1 promoter in Angus, Charolais and Limousin bulls (n = 15 per breed) as well as 141 crossbred beef animals for which meat quality data was available. Eighteen haplotypes were inferred with significant breed variation in haplotype frequencies. The five most frequent SNPs and the four most frequent haplotypes were subsequently tested for association with sensory and technological measures of meat quality in the crossbred population. SNP1, SNP3 and SNP4 (which were subsequently designated regulatory SNPs) and SNP5 were associated with traits that contribute to sensorial and technological measurements of tenderness and texture; Haplotype 1 and haplotype 4 were oppositely correlated with traits contributing to tenderness (P < 0.05). While no single SNP was associated with intramuscular fat (IMF), a clear association with increased IMF and juiciness was observed for haplotype 2. Conclusion The conclusion from this study is that alleles defining haplotypes 2 and 4 could usefully contribute to marker SNP panels used to select individuals with improved IMF\\/juiciness or tenderness in a genome-assisted selection framework.

Epigenetic Alteration by DNA Promoter Hypermethylation of Genes Related to Transforming Growth Factor-β (TGF-β Signaling in Cancer

Directory of Open Access Journals (Sweden)

Kiyoshi Mori

2011-03-01

Full Text Available Epigenetic alterations in cancer, especially DNA methylation and histone modification, exert a significant effect on the deregulated expression of cancer-related genes and lay an epigenetic pathway to carcinogenesis and tumor progression. Global hypomethylation and local hypermethylation of CpG islands in the promoter region, which result in silencing tumor suppressor genes, constitute general and major epigenetic modification, the hallmark of the neoplastic epigenome. Additionally, methylation-induced gene silencing commonly affects a number of genes and increases with cancer progression. Indeed, cancers with a high degree of methylation (CpG island methylator phenotype/CIMP do exist and represent a distinct subset of certain cancers including colorectal, bladder and kidney. On the other hand, signals from the microenvironment, especially those from transforming growth factor-β (TGF-β, induce targeted de novo epigenetic alterations of cancer-related genes. While TGF-β signaling has been implicated in two opposite roles in cancer, namely tumor suppression and tumor promotion, its deregulation is also partly induced by epigenetic alteration itself. Although the epigenetic pathway to carcinogenesis and cancer progression has such reciprocal complexity, the important issue is to identify genes or signaling pathways that are commonly silenced in various cancers in order to find early diagnostic and therapeutic targets. In this review, we focus on the epigenetic alteration by DNA methylation and its role in molecular modulations of the TGF-β signaling pathway that cause or underlie altered cancer-related gene expression in both phases of early carcinogenesis and late cancer progression.

The human luteinizing hormone receptor gene promoter: activation by Sp1 and Sp3 and inhibitory regulation.

Science.gov (United States)

Geng, Y; Tsai-Morris, C H; Zhang, Y; Dufau, M L

1999-09-24

To understand the transcriptional mechanism(s) of human LH receptor (LHR) gene expression, we have identified the dominant functional cis-elements that regulate the activity of the promoter domain (-1 to -176 bp from ATG). Mutagenesis demonstrated that the promoter activity was dependent on two Sp1 domains (-79 bp, -120 bp) in a transformed normal placental cell (PLC) and the choriocarcinoma JAR cell. Both elements interacted with endogenous Sp1 and Sp3 factors but not with Sp2 or Sp4. In Drosophila SL2 cells, the promoter was activated by either Sp1 or Sp3. An ERE half-site (EREhs) at -174 bp was inhibitory (by 100%), but was unresponsive to estradiol and did not bind the estrogen receptor or orphan receptors ERR1 and SF-1. The 5' upstream sequence (-177 to -2056 bp) inhibited promoter activity in PLC by 60%, but only minimally in JAR cells. Activation of the human LHR promoter through Sp1/3 factors is negatively regulated through EREhs and upstream sequences to exert control of gene expression. Copyright 1999 Academic Press.

Transcriptional factor DLX3 promotes the gene expression of enamel matrix proteins during amelogenesis.

Science.gov (United States)

Zhang, Zhichun; Tian, Hua; Lv, Ping; Wang, Weiping; Jia, Zhuqing; Wang, Sainan; Zhou, Chunyan; Gao, Xuejun

2015-01-01

Mutation of distal-less homeobox 3 (DLX3) is responsible for human tricho-dento-osseous syndrome (TDO) with amelogenesis imperfecta, indicating a crucial role of DLX3 in amelogenesis. However, the expression pattern of DLX3 and its specific function in amelogenesis remain largely unknown. The aim of this study was to investigate the effects of DLX3 on enamel matrix protein (EMP) genes. By immunohistochemistry assays of mouse tooth germs, stronger immunostaining of DLX3 protein was identified in ameloblasts in the secretory stage than in the pre-secretory and maturation stages, and the same pattern was found for Dlx3 mRNA using Realtime PCR. In a mouse ameloblast cell lineage, forced expression of DLX3 up-regulated the expression of the EMP genes Amelx, Enam, Klk4, and Odam, whereas knockdown of DLX3 down-regulated these four EMP genes. Further, bioinformatics, chromatin immunoprecipitation, and luciferase assays revealed that DLX3 transactivated Enam, Amelx, and Odam through direct binding to their enhancer regions. Particularly, over-expression of mutant-DLX3 (c.571_574delGGGG, responsible for TDO) inhibited the activation function of DLX3 on expression levels and promoter activities of the Enam, Amelx, and Odam genes. Together, our data show that DLX3 promotes the expression of the EMP genes Amelx, Enam, Klk4, and Odam in amelogenesis, while mutant-DLX3 disrupts this regulatory function, thus providing insights into the molecular mechanisms underlying the enamel defects of TDO disease.

Development of a gene therapy strategy to target hepatocellular carcinoma based inhibition of protein phosphatase 2A using the α-fetoprotein promoter enhancer and pgk promoter: an in vitro and in vivo study

International Nuclear Information System (INIS)

Li, Wei; Tao, Min; Li, Dao-Ming; Chen, Kai; Chen, Zheng; Zong, Yang; Yin, Hong; Xu, Ze-Kuan; Zhu, Yi; Gong, Fei-Ran

2012-01-01

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related deaths worldwide. Current therapies are insufficient, making HCC an intractable disease. Our previous studies confirmed that inhibition of protein phosphatase 2A (PP2A) may provide a promising therapeutic strategy for cancer. Unfortunately, constitutive expression of PP2A in normal tissues limits the application of PP2A inhibition. Thus, a HCC-specific gene delivery system should be developed. The α-fetoprotein (AFP) promoter is commonly used in HCC-specific gene therapy strategies; however, the utility of this approach is limited due to the weak activity of the AFP promoter. It has been shown that linking the AFP enhancer with the promoter of the non-tissue-specific, human housekeeping phosphoglycerate kinase (pgk) gene can generate a strong and HCC-selective promoter. We constructed a HCC-specific gene therapy system to target PP2A using the AFP enhancer/pgk promoter, and evaluated the efficiency and specificity of this system both in vitro and in vivo. AFP enhancer/pgk promoter-driven expression of the dominant negative form of the PP2A catalytic subunit α (DN-PP2Acα) exerted cytotoxic effects against an AFP-positive human hepatoma cell lines (HepG2 and Hep3B), but did not affect AFP-negative human hepatoma cells (SK-HEP-1) or normal human liver cells (L-02). Moreover, AFP enhancer/pgk promoter driven expression of DN-PP2Acα inhibited the growth of AFP-positive HepG2 tumors in nude mice bearing solid tumor xenografts, but did not affect AFP-negative SK-HEP-1 tumors. The novel approach of AFP enhancer/pgk promoter-driven expression of DN-PP2Acα may provide a useful cancer gene therapy strategy to selectively target HCC

Analysis of Msx1 and Msx2 transactivation function in the context of the heat shock 70 (Hspa1b) gene promoter.

Science.gov (United States)

Zhuang, Fengfeng; Nguyen, Manuel P; Shuler, Charles; Liu, Yi-Hsin

2009-04-03

Previous studies have shown that Msx proteins control gene transcription predominantly through repression mechanisms. However, gene expression studies using either the gain-of-function or the loss-of-function mutants revealed many gene targets whose expression require functional Msx proteins. To date, investigations into the mechanisms of Msx-dependent transactivation have been hindered by the lack of a responsive promoter. Here, we demonstrated the usefulness of the mouse Hspa1b promoter in probing Msx-dependent mechanisms of gene activation. We showed that Msx protein activates Hspa1b promoter via its C-terminal domain. The activation absolutely depends on the HSEs and physical interactions between Msx proteins and heat shock factors may play a contributing role.

Negative regulation of human parathyroid hormone gene promoter by vitamin D3 through nuclear factor Y

International Nuclear Information System (INIS)

Jaeaeskelaeinen, T.; Huhtakangas, J.; Maeenpaeae, P.H.

2005-01-01

The negative regulation of the human parathyroid hormone (PTH) gene by biologically active vitamin D 3 (1,25-dihydroxyvitamin D 3 ; 1,25(OH) 2 D 3 ) was studied in rat pituitary GH4C1 cells, which express factors needed for the negative regulation. We report here that NF-Y binds to sequences downstream of the site previously reported to bind the vitamin D receptor (VDR). Additional binding sites for NF-Y reside in the near vicinity and were shown to be important for full activity of the PTH gene promoter. VDR and NF-Y were shown to exhibit mutually exclusive binding to the VDRE region. According to our results, sequestration of binding partners for NF-Y by VDR also affects transcription through a NF-Y consensus binding element in GH4C1 but not in ROS17/2.8 cells. These results indicate that 1,25(OH) 2 D 3 may affect transcription of the human PTH gene both by competitive binding of VDR and NF-Y, and by modulating transcriptional activity of NF-Y

Development of a flexible and potent hypoxia-inducible promoter for tumor-targeted gene expression in attenuated Salmonella

NARCIS (Netherlands)

Mengesha, Asferd; Dubois, Ludwig; Lambin, Philippe; Landuyt, Willy; Chiu, Roland K; Wouters, Bradly G; Theys, Jan

To increase the potential of attenuated Salmonella as gene delivery vectors for cancer treatment, we developed a hypoxia-inducible promoter system to limit gene expression specifically to the tumor. This approach is envisaged to not only increase tumor specificity, but also to target those cells

PMK-1 p38 MAPK promotes cadmium stress resistance, the expression of SKN-1/Nrf and DAF-16 target genes, and protein biosynthesis in Caenorhabditis elegans.

Science.gov (United States)

Keshet, Alex; Mertenskötter, Ansgar; Winter, Sarah A; Brinkmann, Vanessa; Dölling, Ramona; Paul, Rüdiger J

2017-12-01

The mechanisms of cadmium (Cd) resistance are complex and not sufficiently understood. The present study, therefore, aimed at assessing the roles of important components of stress-signaling pathways and of ABC transporters under severe Cd stress in Caenorhabditis elegans. Survival assays on mutant and control animals revealed a significant promotion of Cd resistance by the PMK-1 p38 MAP kinase, the transcription factor DAF-16/FoxO, and the ABC transporter MRP-1. Transcriptome profiling by RNA-Seq on wild type and a pmk-1 mutant under control and Cd stress conditions revealed, inter alia, a PMK-1-dependent promotion of gene expression for the translational machinery. PMK-1 also promoted the expression of target genes of the transcription factors SKN-1/Nrf and DAF-16 in Cd-stressed animals, which included genes for molecular chaperones or immune proteins. Gene expression studies by qRT-PCR confirmed the positive effects of PMK-1 on DAF-16 activity under Cd stress and revealed negative effects of DAF-16 on the expression of genes for MRP-1 and DAF-15/raptor. Additional studies on pmk-1 RNAi-treated wild type and mutant strains provided further information on the effects of PMK-1 on SKN-1 and DAF-16, which resulted in a model of these relationships. The results of this study demonstrate a central role of PMK-1 for the processing of cellular responses to abiotic and biotic stressors, with the promoting effects of PMK-1 on Cd resistance mostly mediated by the transcription factors SKN-1 and DAF-16.

Linkage mapping of candidate genes for induce resistance and growth promotion by trichoderma koningiopsis (th003) in tomato solanum lycopersicum

International Nuclear Information System (INIS)

Simbaqueba, Jaime; Cotes, Alba Marina; Barrero, Luz Stella

2011-01-01

Induced systemic resistance (ISR) is a mechanism by which plants enhance defenses against any stress condition. ISR and growth promotion are enhanced when tomato (Solanum lycopersicum) is inoculated with several strains of Trichoderma ssp. this study aims to genetically map tomato candidate genes involved in ISR and growth promotion induced by the Colombian native isolate Trichoderma koningiopsis th003. Forty-nine candidate genes previously identified on tomato plants treated with th003 and T. hamatum T382 strains were evaluated for polymorphisms and 16 of them were integrated on the highly saturated genetic linkage map named TOMATO EXPEN 2000. The location of six unigenes was similar to the location of resistance gene analogs (RGAS), defense related ests and resistance QTLs previously reported, suggesting new possible candidates for these quantitative trait loci (QTL) regions. The candidate gene-markers may be used for future ISR or growth promotion assisted selection in tomato.

Analysis of the AHR gene proximal promoter GGGGC-repeat polymorphism in lung, breast, and colon cancer

International Nuclear Information System (INIS)

Spink, Barbara C.; Bloom, Michael S.; Wu, Susan; Sell, Stewart; Schneider, Erasmus; Ding, Xinxin; Spink, David C.

2015-01-01

The aryl hydrocarbon receptor (AhR) regulates expression of numerous genes, including those of the CYP1 gene family. With the goal of determining factors that control AHR gene expression, our studies are focused on the role of the short tandem repeat polymorphism, (GGGGC) n , located in the proximal promoter of the human AHR gene. When luciferase constructs containing varying GGGGC repeats were transfected into cancer cell lines derived from the lung, colon, and breast, the number of GGGGC repeats affected AHR promoter activity. The number of GGGGC repeats was determined in DNA from 327 humans and from 38 samples representing 5 species of non-human primates. In chimpanzees and 3 species of macaques, only (GGGGC) 2 alleles were observed; however, in western gorilla, (GGGGC) n alleles with n = 2, 4, 5, 6, 7, and 8 were identified. In all human populations examined, the frequency of (GGGGC) n was n = 4 > 5 ≫ 2, 6. When frequencies of the (GGGGC) n alleles in DNA from patients with lung, colon, or breast cancer were evaluated, the occurrence of (GGGGC) 2 was found to be 8-fold more frequent among lung cancer patients in comparison with its incidence in the general population, as represented by New York State neonates. Analysis of matched tumor and non-tumor DNA samples from the same individuals provided no evidence of microsatellite instability. These studies indicate that the (GGGGC) n short tandem repeats are inherited, and that the (GGGGC) 2 allele in the AHR proximal promoter region should be further investigated with regard to its potential association with lung cancer susceptibility. - Highlights: • The AHR proximal promoter contains a polymorphism, (GGGGC) n , where n = 4 > 5 ≫ 2, 6 • Matched tumor and non-tumor DNA did not show (GGGGC) n microsatellite instability • AHR promoter activity of a construct with (GGGGC) 2 was lower than that of (GGGGC) 4 • The frequency of (GGGGC) 2 in lung cancer patients was 8-fold higher than in neonates • The

Loss of the NKX3.1 tumorsuppressor promotes the TMPRSS2-ERG fusion gene expression in prostate cancer

International Nuclear Information System (INIS)

Thangapazham, Rajesh; Saenz, Francisco; Katta, Shilpa; Mohamed, Ahmed A; Tan, Shyh-Han; Petrovics, Gyorgy; Srivastava, Shiv; Dobi, Albert

2014-01-01

In normal prostate epithelium the TMPRSS2 gene encoding a type II serine protease is directly regulated by male hormones through the androgen receptor. In prostate cancer ERG protooncogene frequently gains hormonal control by seizing gene regulatory elements of TMPRSS2 through genomic fusion events. Although, the androgenic activation of TMPRSS2 gene has been established, little is known about other elements that may interact with TMPRSS2 promoter sequences to modulate ERG expression in TMPRSS2-ERG gene fusion context. Comparative genomic analyses of the TMPRSS2 promoter upstream sequences and pathway analyses were performed by the Genomatix Software. NKX3.1 and ERG genes expressions were evaluated by immunoblot or by quantitative Real-Time PCR (qRT-PCR) assays in response to siRNA knockdown or heterologous expression. QRT-PCR assay was used for monitoring the gene expression levels of NKX3.1-regulated genes. Transcriptional regulatory function of NKX3.1 was assessed by luciferase assay. Recruitment of NKX3.1 to its cognate elements was monitored by Chromatin Immunoprecipitation assay. Comparative analysis of the TMPRSS2 promoter upstream sequences among different species revealed the conservation of binding sites for the androgen inducible NKX3.1 tumor suppressor. Defects of NKX3.1, such as, allelic loss, haploinsufficiency, attenuated expression or decreased protein stability represent established pathways in prostate tumorigenesis. We found that NKX3.1 directly binds to TMPRSS2 upstream sequences and negatively regulates the expression of the ERG protooncogene through the TMPRSS2-ERG gene fusion. These observations imply that the frequently noted loss-of-function of NKX3.1 cooperates with the activation of TMPRSS2-ERG fusions in prostate tumorigenesis

Characterization of a lactose-responsive promoter of ATP-binding cassette (ABC) transporter gene from Lactobacillus acidophilus 05-172.

Science.gov (United States)

Zeng, Zhu; Zuo, Fanglei; Yu, Rui; Zhang, Bo; Ma, Huiqin; Chen, Shangwu

2017-09-01

A novel lactose-responsive promoter of the ATP-binding cassette (ABC) transporter gene Lba1680 of Lactobacillus acidophilus strain 05-172 isolated from a traditionally fermented dairy product koumiss was characterized. In L. acidophilus 05-172, expression of Lba1680 was induced by lactose, with lactose-induced transcription of Lba1680 being 6.1-fold higher than that induced by glucose. This is in contrast to L. acidophilus NCFM, a strain isolated from human feces, in which expression of Lba1680 and Lba1679 is induced by glucose. Both gene expression and enzyme activity assays in L. paracasei transformed with a vector containing the inducible Lba1680 promoter (PLba1680) of strain 05-172 and a heme-dependent catalase gene as reporter confirmed that PLba1680 is specifically induced by lactose. Its regulatory expression could not be repressed by glucose, and was independent of cAMP receptor protein. This lactose-responsive promoter might be used in the expression of functional genes in L. paracasei incorporated into a lactose-rich environment, such as dairy products. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Genetic recombination is targeted towards gene promoter regions in dogs.

Science.gov (United States)

Auton, Adam; Rui Li, Ying; Kidd, Jeffrey; Oliveira, Kyle; Nadel, Julie; Holloway, J Kim; Hayward, Jessica J; Cohen, Paula E; Greally, John M; Wang, Jun; Bustamante, Carlos D; Boyko, Adam R

2013-01-01

The identification of the H3K4 trimethylase, PRDM9, as the gene responsible for recombination hotspot localization has provided considerable insight into the mechanisms by which recombination is initiated in mammals. However, uniquely amongst mammals, canids appear to lack a functional version of PRDM9 and may therefore provide a model for understanding recombination that occurs in the absence of PRDM9, and thus how PRDM9 functions to shape the recombination landscape. We have constructed a fine-scale genetic map from patterns of linkage disequilibrium assessed using high-throughput sequence data from 51 free-ranging dogs, Canis lupus familiaris. While broad-scale properties of recombination appear similar to other mammalian species, our fine-scale estimates indicate that canine highly elevated recombination rates are observed in the vicinity of CpG rich regions including gene promoter regions, but show little association with H3K4 trimethylation marks identified in spermatocytes. By comparison to genomic data from the Andean fox, Lycalopex culpaeus, we show that biased gene conversion is a plausible mechanism by which the high CpG content of the dog genome could have occurred.

Opposite Smad and chicken ovalbumin upstream promoter transcription factor inputs in the regulation of the collagen VII gene promoter by transforming growth factor-beta.

Science.gov (United States)

Calonge, María Julia; Seoane, Joan; Massagué, Joan

2004-05-28

A critical component of the epidermal basement membrane, collagen type VII, is produced by keratinocytes and fibroblasts, and its production is stimulated by the cytokine transforming growth factor-beta (TGF-beta). The gene, COL7A1, is activated by TGF-beta via Smad transcription factors in cooperation with AP1. Here we report a previously unsuspected level of complexity in this regulatory process. We provide evidence that TGF-beta may activate the COL7A1 promoter by two distinct inputs operating through a common region of the promoter. One input is provided by TGF-beta-induced Smad complexes via two Smad binding elements that function redundantly depending on the cell type. The second input is provided by relieving the COL7A1 promoter from chicken ovalbumin upstream promoter transcription factor (COUP-TF)-mediated transcriptional repression. We identified COUP-TFI and -TFII as factors that bind to the TGF-beta-responsive region of the COL7A1 promoter in an expression library screening. COUP-TFs bind to a site between the two Smad binding elements independently of Smad or AP1 and repress the basal and TGF-beta-stimulated activities of this promoter. We provide evidence that endogenous COUP-TF activity represses the COL7A1 promoter. Furthermore, we show that TGF-beta addition causes a rapid and profound down-regulation of COUP-TF expression in keratinocytes and fibroblasts. The results suggest that TGF-beta signaling may exert tight control over COL7A1 by offsetting the balance between opposing Smad and COUP-TFs.

Genome-wide Anaplasma phagocytophilum AnkA-DNA interactions are enriched in intergenic regions and gene promoters and correlate with infection-induced differential gene expression.

Directory of Open Access Journals (Sweden)

J Stephen Dumler

2016-09-01

Full Text Available Anaplasma phagocytophilum, an obligate intracellular prokaryote, infects neutrophils and alters cardinal functions via reprogrammed transcription. Large contiguous regions of neutrophil chromosomes are differentially expressed during infection. Secreted A. phagocytophilum effector AnkA transits into the neutrophil or granulocyte nucleus to complex with DNA in heterochromatin across all chromosomes. AnkA binds to gene promoters to dampen cis-transcription and also has features of matrix attachment region (MAR-binding proteins that regulate three-dimensional chromatin architecture and coordinate transcriptional programs encoded in topologically-associated chromatin domains. We hypothesize that identification of additional AnkA binding sites will better delineate how A. phagocytophilum infection results in reprogramming of the neutrophil genome. Using AnkA-binding ChIP-seq, we showed that AnkA binds broadly throughout all chromosomes in a reproducible pattern, especially at: i intergenic regions predicted to be matrix attachment regions (MARs; ii within predicted lamina-associated domains; and iii at promoters ≤3,000 bp upstream of transcriptional start sites. These findings provide genome-wide support for AnkA as a regulator of cis-gene transcription. Moreover, the dominant mark of AnkA in distal intergenic regions known to be AT-enriched, coupled with frequent enrichment in the nuclear lamina, provides strong support for its role as a MAR-binding protein and genome re-organizer. AnkA must be considered a prime candidate to promote neutrophil reprogramming and subsequent functional changes that belie improved microbial fitness and pathogenicity.

Anyalysis of Msx1 and Msx2 Transactivation Function in the Context of the Heat Shock 70 (Hspa1b) Gene Promoter

Science.gov (United States)

Zhuang, Fengfeng; Nguyen, Manuel P.; Shuler, Charles; Liu, Yi-Hsin

2009-01-01

Previous studies have shown that Msx proteins control gene transcription predominantly through repression mechanisms. However, gene expression studies using either the gain-of-function or the loss-of-function mutants revealed many gene targets whose expression require functional Msx proteins. To date, investigations into the mechanisms of Msx-dependent trans-activation have been hindered by the lack of a responsive promoter. Here, we demonstrated the usefulness of the mouse Hspa1b promoter in probing Msx-dependent mechanisms of gene activation. We showed that Msx protein activates Hspa1b promoter via its C-terminal domain. The activation absolutely depends on the HSEs and physical interactions between Msx proteins and Heat shock factors may play a contributing role. PMID:19338779

A Baculovirus immediate-early gene, ie1, promoter drives efficient expression of a transgene in both Drosophila melanogaster and Bombyx mori.

Directory of Open Access Journals (Sweden)

Mika Masumoto

Full Text Available Many promoters have been used to drive expression of heterologous transgenes in insects. One major obstacle in the study of non-model insects is the dearth of useful promoters for analysis of gene function. Here, we investigated whether the promoter of the immediate-early gene, ie1, from the Bombyx mori nucleopolyhedrovirus (BmNPV could be used to drive efficient transgene expression in a wide variety of insects. We used a piggyBac-based vector with a 3xP3-DsRed transformation marker to generate a reporter construct; this construct was used to determine the expression patterns driven by the BmNPV ie1 promoter; we performed a detailed investigation of the promoter in transgene expression pattern in Drosophila melanogaster and in B. mori. Drosophila and Bombyx belong to different insect orders (Diptera and Lepidoptera, respectively; however, and to our surprise, ie1 promoter-driven expression was evident in several tissues (e.g., prothoracic gland, midgut, and tracheole in both insects. Furthermore, in both species, the ie1 promoter drove expression of the reporter gene from a relatively early embryonic stage, and strong ubiquitous ie1 promoter-driven expression continued throughout the larval, pupal, and adult stages by surface observation. Therefore, we suggest that the ie1 promoter can be used as an efficient expression driver in a diverse range of insect species.

Genetic variants in promoters and coding regions of the muscle glycogen synthase and the insulin-responsive GLUT4 genes in NIDDM

DEFF Research Database (Denmark)

Bjørbaek, C; Echwald, Søren Morgenthaler; Hubricht, P

1994-01-01

To examine the hypothesis that variants in the regulatory or coding regions of the glycogen synthase (GS) and insulin-responsive glucose transporter (GLUT4) genes contribute to insulin-resistant glucose processing of muscle from non-insulin-dependent diabetes mellitus (NIDDM) patients, promoter...... volunteers. By applying inverse polymerase chain reaction and direct DNA sequencing, 532 base pairs (bp) of the GS promoter were identified and the transcriptional start site determined by primer extension. SSCP scanning of the promoter region detected five single nucleotide substitutions, positioned at 42......'-untranslated region, and the coding region of the GLUT4 gene showed four polymorphisms, all single nucleotide substitutions, positioned at -581, 1, 30, and 582. None of the three changes in the regulatory region of the gene had any major influence on expression of the GLUT4 gene in muscle. The variant at 582...

The association of the metalloproteinase-3 gene promoter polymorphisms and the middle cerebral artery stenosis.

Science.gov (United States)

Fu, Chunli; Xing, Yingqi; Song, Xiaonan

2011-04-01

To investigate the association of single nucleotide polymorphism in the matrix metalloproteinase-3 (MMP3) gene promoter with the susceptibility to the middle cerebral artery stenosis. A case-control study was performed by determining the genotype of MMP3 gene promoter region using polymerase chain reaction-restriction fragment length polymorphism in 119 patients with middle cerebral artery stenosis documented by transcranial Doppler compared to 92 control patients. The frequencies of 5A and 6A alleles in MMP3 promoter region were 16.0 and 84.0% respectively in case group compared to 15.8 and 84.2% in control group with no significant difference between the two groups (P > 0.05). No significant difference was also observed in the distribution of genotypes 5A/5A,5A/6A, and 6A/6A between middle cerebral artery stenosis and control groups. Compared to 5A/5A + 5A/6A genotypes,the 6A/6A genotype did not significantly modify the risk of developing the middle cerebral artery stenosis. The MMP3-1171 dupA promoter polymorphisms are not valuable markers of susceptibility of the middle cerebral artery stenosis in this sample of population studied.

CypA, a gene downstream of HIF-1α, promotes the development of PDAC.

Directory of Open Access Journals (Sweden)

Huan Zhang

Full Text Available Hypoxia-inducible factor-1α (HIF-1α is a highly important transcription factor involved in cell metabolism. HIF-1α promotes glycolysis and inhibits of mitochondrial respiration in pancreatic ductal adenocarcinoma (PDAC. In response to tumor hypoxia, cyclophilin A (CypA is over-expressed in various cancer types, and is associated with cell apoptosis, tumor invasion, metastasis, and chemoresistance in PDAC. In this study, we showed that both HIF-1α and CypA expression were significantly associated with lymph node metastasis and tumor stage. The expression of CypA was correlated with HIF-1α. Moreover, the mRNA and protein expression of CypA markedly decreased or increased following the suppression or over-expression of HIF-1α in vitro. Chromatin immunoprecipitation analysis showed that HIF-1α could directly bind to the hypoxia response element (HRE in the CypA promoter regions and regulated CypA expression. Consistent with other studies, HIF-1α and CypA promoted PDAC cell proliferation and invasion, and suppressed apoptosis in vitro. Furthermore, we proved the combination effect of 2-methoxyestradiol and cyclosporin A both in vitro and in vivo. These results suggested that,CypA, a gene downstream of HIF-1α, could promote the development of PDAC. Thus, CypA might serve as a potential therapeutic target for PDAC.

Spatially and Temporally Regulated NRF2 Gene Therapy Using Mcp-1 Promoter in Retinal Ganglion Cell Injury

Directory of Open Access Journals (Sweden)

Kosuke Fujita

2017-06-01

Full Text Available Retinal ganglion cell degeneration triggered by axonal injury is believed to underlie many ocular diseases, including glaucoma and optic neuritis. In these diseases, retinal ganglion cells are affected unevenly, both spatially and temporally, such that healthy and unhealthy cells coexist in different patterns at different time points. Herein, we describe a temporally and spatially regulated adeno-associated virus gene therapy aiming to reduce undesired off-target effects on healthy retinal neurons. The Mcp-1 promoter previously shown to be activated in stressed retinal ganglion cells following murine optic nerve injury was combined with the neuroprotective intracellular transcription factor Nrf2. In this model, Mcp-1 promoter-driven NRF2 expression targeting only stressed retinal ganglion cells showed efficacy equivalent to non-selective cytomegalovirus promoter-driven therapy for preventing cell death. However, cytomegalovirus promoter-mediated NRF2 transcription induced cellular stress responses and death of Brn3A-positive uninjured retinal ganglion cells. Such undesired effects were reduced substantially by adopting the Mcp-1 promoter. Combining a stress-responsive promoter and intracellular therapeutic gene is a versatile approach for specifically targeting cells at risk of degeneration. This strategy may be applicable to numerous chronic ocular and non-ocular conditions.

Co-Targeting Prostate Cancer Epithelium and Bone Stroma by Human Osteonectin-Promoter-Mediated Suicide Gene Therapy Effectively Inhibits Androgen-Independent Prostate Cancer Growth.

Directory of Open Access Journals (Sweden)

Shian-Ying Sung

Full Text Available Stromal-epithelial interaction has been shown to promote local tumor growth and distant metastasis. We sought to create a promising gene therapy approach that co-targets cancer and its supporting stromal cells for combating castration-resistant prostate tumors. Herein, we demonstrated that human osteonectin is overexpressed in the prostate cancer epithelium and tumor stroma in comparison with their normal counterpart. We designed a novel human osteonectin promoter (hON-522E containing positive transcriptional regulatory elements identified in both the promoter and exon 1 region of the human osteonectin gene. In vitro reporter assays revealed that the hON-522E promoter is highly active in androgen receptor negative and metastatic prostate cancer and bone stromal cells compared to androgen receptor-positive prostate cancer cells. Moreover, in vivo prostate-tumor-promoting activity of the hON-522E promoter was confirmed by intravenous administration of an adenoviral vector containing the hON-522E promoter-driven luciferase gene (Ad-522E-Luc into mice bearing orthotopic human prostate tumor xenografts. In addition, an adenoviral vector with the hON-522E-promoter-driven herpes simplex virus thymidine kinase gene (Ad-522E-TK was highly effective against the growth of androgen-independent human prostate cancer PC3M and bone stromal cell line in vitro and in pre-established PC3M tumors in vivo upon addition of the prodrug ganciclovir. Because of the heterogeneity of human prostate tumors, hON-522E promoter-mediated gene therapy has the potential for the treatment of hormone refractory and bone metastatic prostate cancers.

Transcriptional factor DLX3 promotes the gene expression of enamel matrix proteins during amelogenesis.

Directory of Open Access Journals (Sweden)

Zhichun Zhang

Full Text Available Mutation of distal-less homeobox 3 (DLX3 is responsible for human tricho-dento-osseous syndrome (TDO with amelogenesis imperfecta, indicating a crucial role of DLX3 in amelogenesis. However, the expression pattern of DLX3 and its specific function in amelogenesis remain largely unknown. The aim of this study was to investigate the effects of DLX3 on enamel matrix protein (EMP genes. By immunohistochemistry assays of mouse tooth germs, stronger immunostaining of DLX3 protein was identified in ameloblasts in the secretory stage than in the pre-secretory and maturation stages, and the same pattern was found for Dlx3 mRNA using Realtime PCR. In a mouse ameloblast cell lineage, forced expression of DLX3 up-regulated the expression of the EMP genes Amelx, Enam, Klk4, and Odam, whereas knockdown of DLX3 down-regulated these four EMP genes. Further, bioinformatics, chromatin immunoprecipitation, and luciferase assays revealed that DLX3 transactivated Enam, Amelx, and Odam through direct binding to their enhancer regions. Particularly, over-expression of mutant-DLX3 (c.571_574delGGGG, responsible for TDO inhibited the activation function of DLX3 on expression levels and promoter activities of the Enam, Amelx, and Odam genes. Together, our data show that DLX3 promotes the expression of the EMP genes Amelx, Enam, Klk4, and Odam in amelogenesis, while mutant-DLX3 disrupts this regulatory function, thus providing insights into the molecular mechanisms underlying the enamel defects of TDO disease.

Development of a promoter shutoff system in Aspergillus oryzae using a sorbitol-sensitive promoter.

Science.gov (United States)

Oda, Ken; Terado, Shiho; Toyoura, Rieko; Fukuda, Hisashi; Kawauchi, Moriyuki; Iwashita, Kazuhiro

2016-09-01

Promoter shutoff is a general method for analyzing essential genes, but in the fungus Aspergillus oryzae, no tightly repressed promoters have been reported. To overcome the current limitations of conditional promoters, we examined sorbitol- and galactose-responsive genes using microarrays to identify regulatable genes with only minor physiological and genetic effects. We identified two sorbitol-induced genes (designated as sorA and sorB), cloned their promoters, and built a regulated egfp and brlA expression system. Growth medium-dependent enhanced green fluorescence protein (EGFP) fluorescence and conidiation were confirmed for egfp and brlA under the control of their respective promoters. We also used this shutoff system to regulate the essential rhoA, which demonstrated the expected growth inhibition under repressed growth conditions. Our new sorbitol promoter shutoff system developed can serve as a valuable new tool for essential gene analyses of filamentous fungi.

Cloning and characterization of the promoter of the 9-cis-epoxycarotenoid dioxygenase gene in Arachis hypogaea L.

Science.gov (United States)

Liang, Jianhua; Yang, Lixia; Chen, Xiong; Li, Ling; Guo, Dongliang; Li, Haihang; Zhang, Biyu

2009-09-01

We cloned the promoter of the 9-cis-epoxycarotenoid dioxygenase gene from Arachis hypogaea L. beta-Glucuronidase (GUS) histochemical staining and GUS activity assay indicated that the activity of the promoter was exhibited predominantly in the leaves and enhanced by water and NaCl stresses, and by application of abscisic acid (ABA) and salicylic acid (SA) in transgenic Arabidopsis. Moreover, two novel ABRE-like (abscisic acid response element) elements were identified in the promoter region.

Characterization and functional analyses of the human G protein-coupled receptor kinase 4 gene promoter.

Science.gov (United States)

Hasenkamp, Sandra; Telgmann, Ralph; Staessen, Jan A; Hagedorn, Claudia; Dördelmann, Corinna; Bek, Martin; Brand-Herrmann, Stefan-Martin; Brand, Eva

2008-10-01

The G protein-coupled receptor kinase 4 is involved in renal sodium handling and blood pressure regulation. Missense variants have already been tested functionally and are associated with hypertension, but no data on promoter analyses are yet available. We scanned 94 hypertensive white subjects for genetic variation and performed promoter reporter gene analyses in HEK293T, COS7, and SaOs-2 cells. Transient transfections with various full lengths and wild-type deletion constructs revealed that 1851 bp of the flanking region and 275 bp of the 5'-untranslated region were sufficient for transcriptional activities and composed a powerful cis-active element in the distal 293 bp. The -1702T and +2T alleles resulted in drastic general reductions of promoter function, whereas an activity increasing effect of +268C was cell type specific. Electrophoretic mobility-shift assay, supershift, and cotransfection analyses of transcription factor binding sites predicted in silico (Alibaba2.1/Transfac7) resulted in allele-specific binding patterns of nuclear proteins and identified the participation of CCAAT/enhancer-binding protein transcription factor family members. The G protein-coupled receptor kinase 4 core promoter resides in the first 1851 bp upstream of its transcription start site. The 4 identified genetic variants within this region exert allele-specific impact on both cell type- and stimulation-dependent transcription and may affect the expression balance of renal G protein-coupled receptor kinase 4.

pcaGoPromoter--an R package for biological and regulatory interpretation of principal components in genome-wide gene expression data

DEFF Research Database (Denmark)

Hansen, Morten; Gerds, Thomas Alexander; Nielsen, Ole Haagen

2012-01-01

Analyzing data obtained from genome-wide gene expression experiments is challenging due to the quantity of variables, the need for multivariate analyses, and the demands of managing large amounts of data. Here we present the R package pcaGoPromoter, which facilitates the interpretation of genome.......g., cell cycle progression and the predicted involvement of expected transcription factors, including E2F. In addition, unexpected results, e.g., cholesterol synthesis in serum-depleted cells and NF-¿B activation in inhibitor treated cells, were noted. In summary, the pcaGoPromoter R package provides...

Identification of a seed coat-specific promoter fragment from the Arabidopsis MUCILAGE-MODIFIED4 gene.

Science.gov (United States)

Dean, Gillian H; Jin, Zhaoqing; Shi, Lin; Esfandiari, Elahe; McGee, Robert; Nabata, Kylie; Lee, Tiffany; Kunst, Ljerka; Western, Tamara L; Haughn, George W

2017-09-01

The Arabidopsis seed coat-specific promoter fragment described is an important tool for basic and applied research in Brassicaceae species. During differentiation, the epidermal cells of the Arabidopsis seed coat produce and secrete large quantities of mucilage. On hydration of mature seeds, this mucilage becomes easily accessible as it is extruded to form a tightly attached halo at the seed surface. Mucilage is composed mainly of pectin, and also contains the key cell wall components cellulose, hemicellulose, and proteins, making it a valuable model for studying numerous aspects of cell wall biology. Seed coat-specific promoters are an important tool that can be used to assess the effects of expressing biosynthetic enzymes and diverse cell wall-modifying proteins on mucilage structure and function. Additionally, they can be used for production of easily accessible recombinant proteins of commercial interest. The MUCILAGE-MODIFIED4 (MUM4) gene is expressed in a wide variety of plant tissues and is strongly up-regulated in the seed coat during mucilage synthesis, implying the presence of a seed coat-specific region in its promoter. Promoter deletion analysis facilitated isolation of a 308 base pair sequence (MUM4 0.3Pro ) that directs reporter gene expression in the seed coat cells of both Arabidopsis and Camelina sativa, and is regulated by the same transcription factor cascade as endogenous MUM4. Therefore, MUM4 0.3Pro is a promoter fragment that serves as a new tool for seed coat biology research.

Modification of epigenetic patterns in low birth weight children: importance of hypomethylation of the ACE gene promoter.

Science.gov (United States)

Rangel, Marina; dos Santos, Jéssica Cassilla; Ortiz, Paula Helena Lima; Hirata, Mario; Jasiulionis, Miriam Galvonas; Araujo, Ronaldo C; Ierardi, Daniela Filippini; Franco, Maria do Carmo

2014-01-01

There is a growing body of evidence that epigenetic alterations are involved in the pathological mechanisms of many chronic disorders linked to fetal programming. Angiotensin-converting enzyme (ACE) appears as one candidate gene that brings new insights into the epigenetic control and later development of diseases. In this view, we have postulated that epigenetic modifications in the ACE gene might show different interactions between birth weight (BW), blood pressure levels, plasma ACE activity and ACE I/D polymorphism. To explore this hypothesis, we performed a cross-sectional study to evaluate the DNA methylation of 3 CpG sites using pyrosequencing within the ACE gene promoter of peripheral blood leukocytes from 45 LBW children compared with 70 NBW children. Our results have revealed that LBW children have lower methylation levels (PACE activity (P = 0.001). Adjusting for prematurity, gender, age, body mass index, and family history of cardiovascular disease did not alter these findings. We have also performed analyses of individual CpG sites. The frequency of DNA methylation was significantly different at two CpG sites (site 1: nucleotide position +555; and site 3: nucleotide position +563). In addition, we have found a significant inverse correlation between degree of DNA methylation and both ACE activity (PACE gene promoter is associated with LBW in 6 to 12 year-old children. The magnitude of these epigenetic changes appears to be clinically important, which is supported by the observation that discrete changes in DNA methylation can affect systolic blood pressure and ACE protein activity levels.

Anyalysis of Msx1 and Msx2 Transactivation Function in the Context of the Heat Shock 70 (Hspa1b) Gene Promoter

OpenAIRE

Zhuang, Fengfeng; Nguyen, Manuel P.; Shuler, Charles; Liu, Yi-Hsin

2009-01-01

Previous studies have shown that Msx proteins control gene transcription predominantly through repression mechanisms. However, gene expression studies using either the gain-of-function or the loss-of-function mutants revealed many gene targets whose expression require functional Msx proteins. To date, investigations into the mechanisms of Msx-dependent trans-activation have been hindered by the lack of a responsive promoter. Here, we demonstrated the usefulness of the mouse Hspa1b promoter in...

CHIR99021 promotes self-renewal of mouse embryonic stem cells by modulation of protein-encoding gene and long intergenic non-coding RNA expression

Energy Technology Data Exchange (ETDEWEB)

Wu, Yongyan [College of Veterinary Medicine, Northwest A and F University, Yangling 712100, Shaanxi (China); Key Laboratory of Animal Biotechnology, Ministry of Agriculture, Northwest A and F University, Yangling 712100, Shaanxi (China); Ai, Zhiying [Key Laboratory of Animal Biotechnology, Ministry of Agriculture, Northwest A and F University, Yangling 712100, Shaanxi (China); College of Life Sciences, Northwest A and F University, Yangling 712100, Shaanxi (China); Yao, Kezhen [College of Veterinary Medicine, Northwest A and F University, Yangling 712100, Shaanxi (China); Key Laboratory of Animal Biotechnology, Ministry of Agriculture, Northwest A and F University, Yangling 712100, Shaanxi (China); Cao, Lixia; Du, Juan; Shi, Xiaoyan [Key Laboratory of Animal Biotechnology, Ministry of Agriculture, Northwest A and F University, Yangling 712100, Shaanxi (China); College of Life Sciences, Northwest A and F University, Yangling 712100, Shaanxi (China); Guo, Zekun, E-mail: gzk@nwsuaf.edu.cn [College of Veterinary Medicine, Northwest A and F University, Yangling 712100, Shaanxi (China); Key Laboratory of Animal Biotechnology, Ministry of Agriculture, Northwest A and F University, Yangling 712100, Shaanxi (China); Zhang, Yong, E-mail: zhylab@hotmail.com [College of Veterinary Medicine, Northwest A and F University, Yangling 712100, Shaanxi (China); Key Laboratory of Animal Biotechnology, Ministry of Agriculture, Northwest A and F University, Yangling 712100, Shaanxi (China)

2013-10-15

Embryonic stem cells (ESCs) can proliferate indefinitely in vitro and differentiate into cells of all three germ layers. These unique properties make them exceptionally valuable for drug discovery and regenerative medicine. However, the practical application of ESCs is limited because it is difficult to derive and culture ESCs. It has been demonstrated that CHIR99021 (CHIR) promotes self-renewal and enhances the derivation efficiency of mouse (m)ESCs. However, the downstream targets of CHIR are not fully understood. In this study, we identified CHIR-regulated genes in mESCs using microarray analysis. Our microarray data demonstrated that CHIR not only influenced the Wnt/β-catenin pathway by stabilizing β-catenin, but also modulated several other pluripotency-related signaling pathways such as TGF-β, Notch and MAPK signaling pathways. More detailed analysis demonstrated that CHIR inhibited Nodal signaling, while activating bone morphogenetic protein signaling in mESCs. In addition, we found that pluripotency-maintaining transcription factors were up-regulated by CHIR, while several developmental-related genes were down-regulated. Furthermore, we found that CHIR altered the expression of epigenetic regulatory genes and long intergenic non-coding RNAs. Quantitative real-time PCR results were consistent with microarray data, suggesting that CHIR alters the expression pattern of protein-encoding genes (especially transcription factors), epigenetic regulatory genes and non-coding RNAs to establish a relatively stable pluripotency-maintaining network. - Highlights: • Combined use of CHIR with LIF promotes self-renewal of J1 mESCs. • CHIR-regulated genes are involved in multiple pathways. • CHIR inhibits Nodal signaling and promotes Bmp4 expression to activate BMP signaling. • Expression of epigenetic regulatory genes and lincRNAs is altered by CHIR.

CHIR99021 promotes self-renewal of mouse embryonic stem cells by modulation of protein-encoding gene and long intergenic non-coding RNA expression

International Nuclear Information System (INIS)

Wu, Yongyan; Ai, Zhiying; Yao, Kezhen; Cao, Lixia; Du, Juan; Shi, Xiaoyan; Guo, Zekun; Zhang, Yong

2013-01-01

Embryonic stem cells (ESCs) can proliferate indefinitely in vitro and differentiate into cells of all three germ layers. These unique properties make them exceptionally valuable for drug discovery and regenerative medicine. However, the practical application of ESCs is limited because it is difficult to derive and culture ESCs. It has been demonstrated that CHIR99021 (CHIR) promotes self-renewal and enhances the derivation efficiency of mouse (m)ESCs. However, the downstream targets of CHIR are not fully understood. In this study, we identified CHIR-regulated genes in mESCs using microarray analysis. Our microarray data demonstrated that CHIR not only influenced the Wnt/β-catenin pathway by stabilizing β-catenin, but also modulated several other pluripotency-related signaling pathways such as TGF-β, Notch and MAPK signaling pathways. More detailed analysis demonstrated that CHIR inhibited Nodal signaling, while activating bone morphogenetic protein signaling in mESCs. In addition, we found that pluripotency-maintaining transcription factors were up-regulated by CHIR, while several developmental-related genes were down-regulated. Furthermore, we found that CHIR altered the expression of epigenetic regulatory genes and long intergenic non-coding RNAs. Quantitative real-time PCR results were consistent with microarray data, suggesting that CHIR alters the expression pattern of protein-encoding genes (especially transcription factors), epigenetic regulatory genes and non-coding RNAs to establish a relatively stable pluripotency-maintaining network. - Highlights: • Combined use of CHIR with LIF promotes self-renewal of J1 mESCs. • CHIR-regulated genes are involved in multiple pathways. • CHIR inhibits Nodal signaling and promotes Bmp4 expression to activate BMP signaling. • Expression of epigenetic regulatory genes and lincRNAs is altered by CHIR

Prognostic Significance of Promoter DNA Hypermethylation of cysteine dioxygenase 1 (CDO1 Gene in Primary Breast Cancer.

Directory of Open Access Journals (Sweden)

Naoko Minatani

Full Text Available Using pharmacological unmasking microarray, we identified promoter DNA methylation of cysteine dioxygenase 1 (CDO1 gene in human cancer. In this study, we assessed the clinicopathological significance of CDO1 methylation in primary breast cancer (BC with no prior chemotherapy. The CDO1 DNA methylation was quantified by TaqMan methylation specific PCR (Q-MSP in 7 BC cell lines and 172 primary BC patients with no prior chemotherapy. Promoter DNA of the CDO1 gene was hypermethylated in 6 BC cell lines except SK-BR3, and CDO1 gene expression was all silenced at mRNA level in the 7 BC cell lines. Quantification of CDO1 methylation was developed using Q-MSP, and assessed in primary BC. Among the clinicopathologic factors, CDO1 methylation level was not statistically significantly associated with any prognostic factors. The log-rank plot analysis elucidated that the higher methylation the tumors harbored, the poorer prognosis the patients exhibited. Using the median value of 58.0 as a cut-off one, disease specific survival in BC patients with CDO1 hypermethylation showed significantly poorer prognosis than those with hypomethylation (p = 0.004. Multivariate Cox proportional hazards model identified that CDO1 hypermethylation was prognostic factor as well as Ki-67 and hormone receptor status. The most intriguingly, CDO1 hypermethylation was of robust prognostic relevance in triple negative BC (p = 0.007. Promoter DNA methylation of CDO1 gene was robust prognostic indicator in primary BC patients with no prior chemotherapy. Prognostic relevance of the CDO1 promoter DNA methylation is worthy of being paid attention in triple negative BC cancer.

Construction and expression of secreting type human TRAIL gene vector mediated by hypoxia/radiation double sensitive promoter

International Nuclear Information System (INIS)

Yang Yanming; Jia Xiaojing; Qu Yaqin; Li Yanbo

2009-01-01

Objective: To construct secreting type human TRAIL (shTRAIL) gene vector pcDNA3.1-HRE/Egr1-shTRAIL mediated by hypoxia/radiation double sensitive promoter, and observe the effect of hypoxia and radiation on shTRAIL. Methods: HRE upper and lower strands were gotten by chemical synthesis, double strands HRE was gotten by PCR; pMD19T-Egr1 was digested by Sac I and Hind III, then Egr1 was obtained, pshuttle-shTRAIL was digested by Kpn I and BamH I, then shTRAIL was obtained; HRE/Egr1 double sensitive promoter mediated shTRAIL expression vector pcDNA3.1-HRE/Egr1-shTRAIL was constructed by gene recombination technique, it was identified correctly by enzyme digestion, PCR and sequencing. A549 cells were divided into normal, hypoxia (0.1%), irradiation (6 Gy) and hypoxia + irradiation groups. Results: After enzyme digestion by BamH I and Sma I, the fragments which lengths were 1284 bp and 4 998 bp, 2 292 bp and 3 990 bp were obtained; the vector was amplified by PCR with Egr1 and shTRAIL primer, the products which lengthens were 469 bp and 820 bp were obtained; pcDNA3.1-HRE/Egr1-shTRAIL was sequenced, the result was same to designed, this demonstrated that the construction was right. The vectors were transfected into A549 cells of adenocarcinoma of lung, the expression levels of shTRAIL mRNA and protein were increased after treated with hypoxia and radiation, it had statistically significant differences compared with normal group (P<0.05), and when they were combinated, the effect was more obvious. Conclusion: Secreting type human TRAIL gene vector pcDNA3.1-HRE/Egr1-shTRAIL mediated by hypoxia/radiation double sensitive promoter is constructed successfully, and hypoxia and radiation could increase the expression of TRAIL, and they have synergetic effect. (authors)

Promoter Hypermethylation of the EMP3 Gene in a Series of 229 Human Gliomas

Directory of Open Access Journals (Sweden)

Marta Mellai

2013-01-01

Full Text Available The epithelial membrane protein 3 (EMP3 is a candidate tumor suppressor gene in the critical region 19q13.3 for several solid tumors, including tumors of the nervous systems. The aim of this study was to investigate the EMP3 promoter hypermethylation status in a series of 229 astrocytic and oligodendroglial tumors and in 16 GBM cell lines. The analysis was performed by methylation-specific PCR and capillary electrophoresis. Furthermore, the EMP3 expression at protein level was evaluated by immunohistochemistry and Western blotting analysis. Associations of EMP3 hypermethylation with total 1p/19q codeletion, MGMT promoter hypermethylation, IDH1/IDH2 and TP53 mutations, and EGFR amplification were studied, as well as its prognostic significance. The EMP3 promoter hypermethylation has been found in 39.5% of gliomas. It prevailed in low-grade tumors, especially in gliomas with an oligodendroglial component, and in sGBMs upon pGBMs. In oligodendroglial tumors, it was strongly associated with both IDH1/IDH2 mutations and total 1p/19q codeletion and inversely with EGFR gene amplification. No association was found with MGMT hypermethylation and TP53 mutations. In the whole series, the EMP3 hypermethylation status correlated with 19q13.3 loss and lack of EMP3 expression at protein level. A favorable prognostic significance on overall survival of the EMP3 promoter hypermethylation was found in patients with oligodendroglial tumors.

Pairwise comparisons of ten porcine tissues identify differential transcriptional regulation at the gene, isoform, promoter and transcription start site level

DEFF Research Database (Denmark)

Farajzadeh, Leila; Hornshøj, Henrik; Momeni, Jamal

2013-01-01

, isoform, and transcription start site (TSS), and promoter level showed that several of the genes differed at all four levels. Interestingly, these genes were mainly annotated to the "electron transport chain" and neuronal differentiation, emphasizing that "tissue important" genes are regulated at several...

Functional dissection of the promoter of the pollen-specific gene NTP303 reveals a novel pollen-specific, and conserved cis-regulatory element.

Science.gov (United States)

Weterings, K; Schrauwen, J; Wullems, G; Twell, D

1995-07-01

Regulatory elements within the promoter of the pollen-specific NTP303 gene from tobacco were analysed by transient and stable expression analyses. Analysis of precisely targeted mutations showed that the NTP303 promoter is not regulated by any of the previously described pollen-specific cis-regulatory elements. However, two adjacent regions from -103 to -86 bp and from -86 to -59 bp were shown to contain sequences which positively regulated the NTP303 promoter. Both of these regions were capable of driving pollen-specific expression from a heterologous promoter, independent of orientation and in an additive manner. The boundaries of the minimal, functional NTP303 promoter were determined to lie within the region -86 to -51 bp. The sequence AAATGA localized from -94 to -89 bp was identified as a novel cis-acting element, of which the TGA triplet was shown to comprise an active part. This element was shown to be completely conserved in the similarly regulated promoter of the Bp 10 gene from Brassica napus encoding a homologue of the NTP303 gene.

ΔNp73 enhances promoter activity of TGF-β induced genes.

Directory of Open Access Journals (Sweden)

Maarten Niemantsverdriet

Full Text Available The p53 homolog p73 is frequently overexpressed in cancers. Especially the transactivation domain truncated isoform ΔNp73 has oncogenic properties and its upregulation is associated with poor patient survival. It has been shown that ΔNp73 has an inhibitory effect on the transactivation capacity of p53 and other p73 isoforms. Here, we confirm this finding but surprisingly find that ΔNp73 may also stimulate the expression of TGF-β signaling targets. Promoter-reporter analysis indicated that the presence of Smad Binding Elements (SBE in the promoter is sufficient for stimulation of gene expression by ΔNp73. TGF-β signaling was less efficient in ΔNp73 downregulated cells, whereas tetracycline induced ΔNp73 increased expression of endogenous TGF-β regulated genes PAI-1 and Col1a1. Pull-down assays with SBE DNA suggest that ΔNp73 enhances smad3/4 binding to SBEs, thereby stimulating TGF-β signaling. Chromatin immunoprecipitation assays confirmed a direct interaction between ΔNp73 and SBE. Given the role of TGF-β signaling in carcinogenesis, tumor invasion and metastasis via targets like PAI-1 and Col1a1, our data suggest a model on how this effect of ΔNp73 could be a contributing factor in cancer progression.

Porcine MYF6 gene: sequence, homology analysis, and variation in the promoter region.

Science.gov (United States)

Wyszyńska-Koko, J; Kurył, J

2004-01-01

MYF6 gene codes for the bHLH transcription factor belonging to MyoD family. Its expression accompanies the processes of differentiation and maturation of myotubes during embriogenesis and continues on a relatively high level after birth, affecting the muscle phenotype. The porcine MYF6 gene was amplified and sequenced and compared with MYF6 gene sequences of other species. The amino acid sequence was deduced and an interspecies homology analysis was performed. Myf-6 protein shows a high conservation among species of 99 and 97% identity when comparing pig with cow and human, respectively, and of 93% when comparing pig with mouse and rat. The single nucleotide polymorphism (SNP) was revealed within the promoter region, which appeared to be T --> C transition recognized by a MspI restriction enzyme.

Gene silencing of HPV16 E6/E7 induced by promoter-targeting siRNA in SiHa cells

OpenAIRE

Hong, D; Lu, W; Ye, F; Hu, Y; Xie, X

2009-01-01

Background: Recently, transcriptional gene silencing induced by small interfering RNA (siRNA) was found in mammalian and human cells. However, previous studies focused on endogenous genes. Methods: In this study, we designed siRNA targeting the promoter of human papillomavirus 16 E6/E7 and transfected it into the cervical cancer cell line, SiHa. E6 and E7 mRNA and protein expression were detected in cells treated by promoter-targeting siRNA. Futhermore, cellular growth, proliferation, apoptos...

Transcriptional analysis of heterologous gene expression using the endogenous sD promoter from Bacillus halodurans

CSIR Research Space (South Africa)

Crampton, Michael C

2010-07-01

Full Text Available This presentation focused on the transcriptional analysis of heterologous gene expression using the endogenous sD promoter from Bacillus halodurans. It concludes to a successful implementation of a high throughput mRNA sandwich hybridisation...

New PAH gene promoter KLF1 and 3'-region C/EBPalpha motifs influence transcription in vitro.

Science.gov (United States)

Klaassen, Kristel; Stankovic, Biljana; Kotur, Nikola; Djordjevic, Maja; Zukic, Branka; Nikcevic, Gordana; Ugrin, Milena; Spasovski, Vesna; Srzentic, Sanja; Pavlovic, Sonja; Stojiljkovic, Maja

2017-02-01

Phenylketonuria (PKU) is a metabolic disease caused by mutations in the phenylalanine hydroxylase (PAH) gene. Although the PAH genotype remains the main determinant of PKU phenotype severity, genotype-phenotype inconsistencies have been reported. In this study, we focused on unanalysed sequences in non-coding PAH gene regions to assess their possible influence on the PKU phenotype. We transiently transfected HepG2 cells with various chloramphenicol acetyl transferase (CAT) reporter constructs which included PAH gene non-coding regions. Selected non-coding regions were indicated by in silico prediction to contain transcription factor binding sites. Furthermore, electrophoretic mobility shift assay (EMSA) and supershift assays were performed to identify which transcriptional factors were engaged in the interaction. We found novel KLF1 motif in the PAH promoter, which decreases CAT activity by 50 % in comparison to basal transcription in vitro. The cytosine at the c.-170 promoter position creates an additional binding site for the protein complex involving KLF1 transcription factor. Moreover, we assessed for the first time the role of a multivariant variable number tandem repeat (VNTR) region located in the 3'-region of the PAH gene. We found that the VNTR3, VNTR7 and VNTR8 constructs had approximately 60 % of CAT activity. The regulation is mediated by the C/EBPalpha transcription factor, present in protein complex binding to VNTR3. Our study highlighted two novel promoter KLF1 and 3'-region C/EBPalpha motifs in the PAH gene which decrease transcription in vitro and, thus, could be considered as PAH expression modifiers. New transcription motifs in non-coding regions will contribute to better understanding of the PKU phenotype complexity and may become important for the optimisation of PKU treatment.

Hypermethylation of gene promoters in peripheral blood leukocytes in humans long term after radiation exposure

Energy Technology Data Exchange (ETDEWEB)

Kuzmina, Nina S., E-mail: nin-kuzmin@youndex.ru; Lapteva, Nellya Sh.; Rubanovich, Alexander V.

2016-04-15

Some human genes known to undergo age-related promoter hypermethylation. These epigenetic modifications are similar to those occurring in the course of certain diseases, e.g. some types of cancer, which in turn may also associate with age. Given external genotoxic factors may additionally contribute to hypermethylation, this study was designed to analyzes, using methylation-sensitive polymerase chain reaction (PCR), the CpG island hypermethylation in RASSF1A, CDKN2A (including p16/INK4A and p14/ARF) and GSTP1 promoters in peripheral blood leukocytes of individuals exposed to ionizing radiation long time ago. One hundred and twenty-four irradiated subjects (24–77 years old at sampling: 83 Chernobyl Nuclear Power Plant clean-up workers, 21 nuclear workers, 20 residents of territories with radioactive contamination) and 208 unirradiated volunteers (19–77 years old at sampling) were enrolled. In addition, 74 non-exposed offspring (2–51 years old at sampling) born to irradiated parents were examined. The frequency of individuals displaying promoter methylation of at least one gene in exposed group was significantly higher as compared to the control group (OR=5.44, 95% CI=2.62–11.76, p=3.9×10{sup −7}). No significant difference was found between the frequency of subjects with the revealed promoter methylation in the group of offspring born to irradiated parents and in the control group. The increase in the number of methylated loci of RASSF1A and p14/ARF was associated with age (β=0.242; p=1.7×10{sup −5}). In contrast, hypermethylation of p16/INK4A and GSTP1 genes correlated with the fact of radiation exposure only (β=0.290; p=1.7×10{sup −7}). The latter finding demonstrates that methylation changes in blood leukocytes of healthy subjects exposed to radiation resemble those reported in human malignancies. Additional studies are required to identify the dose-response of epigenetic markers specifically associating with radiation-induced premature aging

Hypermethylation of gene promoters in peripheral blood leukocytes in humans long term after radiation exposure

International Nuclear Information System (INIS)

Kuzmina, Nina S.; Lapteva, Nellya Sh.; Rubanovich, Alexander V.

2016-01-01

Some human genes known to undergo age-related promoter hypermethylation. These epigenetic modifications are similar to those occurring in the course of certain diseases, e.g. some types of cancer, which in turn may also associate with age. Given external genotoxic factors may additionally contribute to hypermethylation, this study was designed to analyzes, using methylation-sensitive polymerase chain reaction (PCR), the CpG island hypermethylation in RASSF1A, CDKN2A (including p16/INK4A and p14/ARF) and GSTP1 promoters in peripheral blood leukocytes of individuals exposed to ionizing radiation long time ago. One hundred and twenty-four irradiated subjects (24–77 years old at sampling: 83 Chernobyl Nuclear Power Plant clean-up workers, 21 nuclear workers, 20 residents of territories with radioactive contamination) and 208 unirradiated volunteers (19–77 years old at sampling) were enrolled. In addition, 74 non-exposed offspring (2–51 years old at sampling) born to irradiated parents were examined. The frequency of individuals displaying promoter methylation of at least one gene in exposed group was significantly higher as compared to the control group (OR=5.44, 95% CI=2.62–11.76, p=3.9×10 −7 ). No significant difference was found between the frequency of subjects with the revealed promoter methylation in the group of offspring born to irradiated parents and in the control group. The increase in the number of methylated loci of RASSF1A and p14/ARF was associated with age (β=0.242; p=1.7×10 −5 ). In contrast, hypermethylation of p16/INK4A and GSTP1 genes correlated with the fact of radiation exposure only (β=0.290; p=1.7×10 −7 ). The latter finding demonstrates that methylation changes in blood leukocytes of healthy subjects exposed to radiation resemble those reported in human malignancies. Additional studies are required to identify the dose-response of epigenetic markers specifically associating with radiation-induced premature aging and/or with

A pilot study on genetic variation in purine-rich elements in the nephrin gene promoter in type 2 diabetic patients

Directory of Open Access Journals (Sweden)

RODRIGO GONZÁLEZ

2007-01-01

Full Text Available Diabetic nephropathy (DN is one of the major complications of type 2 diabetes and is associated with coronary disease. Nephrin, a protein mainly expressed in glomeruli, is decreased in DN and other kidney diseases. Since insulin levels are misregulated in type 2 diabetes, a possible connection between DN and its decreased nephrin expression could be the presence of regulatory elements responsive to insulin in the nephrin gene (NPHS1 promoter region. In this work, using bioinformatic tools, we identified a purine-rich GAGA element in the nephrin gene promoter and conducted a genomic study in search of the presence of polymorphisms in this element and its possible association with DN in type 2 diabetic patients. We amplified and sequenced a 514 bp promoter region of 100 individuals and found no genetic variants in the purine-rich GAGA-box of the nephrin gene promoter between groups of patients with diabetes type 2 with and without renal and coronary complications, control patients without diabetes and healthy controls

Efficiently engineered cell sheet using a complex of polyethylenimine–alginate nanocomposites plus bone morphogenetic protein 2 gene to promote new bone formation

Science.gov (United States)

Jin, Han; Zhang, Kai; Qiao, Chunyan; Yuan, Anliang; Li, Daowei; Zhao, Liang; Shi, Ce; Xu, Xiaowei; Ni, Shilei; Zheng, Changyu; Liu, Xiaohua; Yang, Bai; Sun, Hongchen

2014-01-01

Regeneration of large bone defects is a common clinical problem. Recently, stem cell sheet has been an emerging strategy in bone tissue engineering. To enhance the osteogenic potential of stem cell sheet, we fabricated bone morphogenetic protein 2 (BMP-2) gene-engineered cell sheet using a complex of polyethylenimine–alginate (PEI–al) nanocomposites plus human BMP-2 complementary(c)DNA plasmid, and studied its osteogenesis in vitro and in vivo. PEI–al nanocomposites carrying BMP-2 gene could efficiently transfect bone marrow mesenchymal stem cells. The cell sheet was made by culturing the cells in medium containing vitamin C for 10 days. Assays on the cell culture showed that the genetically engineered cells released the BMP-2 for at least 14 days. The expression of osteogenesis-related gene was increased, which demonstrated that released BMP-2 could effectively induce the cell sheet osteogenic differentiation in vitro. To further test the osteogenic potential of the cell sheet in vivo, enhanced green fluorescent protein or BMP-2-producing cell sheets were treated on the cranial bone defects. The results indicated that the BMP-2-producing cell sheet group was more efficient than other groups in promoting bone formation in the defect area. Our results suggested that PEI–al nanocomposites efficiently deliver the BMP-2 gene to bone marrow mesenchymal stem cells and that BMP-2 gene-engineered cell sheet is an effective way for promoting bone regeneration. PMID:24855355

Analysis of the AHR gene proximal promoter GGGGC-repeat polymorphism in lung, breast, and colon cancer

Energy Technology Data Exchange (ETDEWEB)

Spink, Barbara C. [Wadsworth Center, New York State Department of Health, Albany, NY 12201 (United States); Bloom, Michael S. [Department of Environmental Health Sciences, School of Public Health, University at Albany, State University of New York, Albany, NY 12201 (United States); Wu, Susan [Wadsworth Center, New York State Department of Health, Albany, NY 12201 (United States); Sell, Stewart; Schneider, Erasmus [Wadsworth Center, New York State Department of Health, Albany, NY 12201 (United States); Department of Biomedical Sciences, School of Public Health, University at Albany, State University of New York, Albany, NY 12201 (United States); Ding, Xinxin [Wadsworth Center, New York State Department of Health, Albany, NY 12201 (United States); Department of Environmental Health Sciences, School of Public Health, University at Albany, State University of New York, Albany, NY 12201 (United States); Department of Biomedical Sciences, School of Public Health, University at Albany, State University of New York, Albany, NY 12201 (United States); Spink, David C., E-mail: spink@wadsworth.org [Wadsworth Center, New York State Department of Health, Albany, NY 12201 (United States); Department of Environmental Health Sciences, School of Public Health, University at Albany, State University of New York, Albany, NY 12201 (United States)

2015-01-01

The aryl hydrocarbon receptor (AhR) regulates expression of numerous genes, including those of the CYP1 gene family. With the goal of determining factors that control AHR gene expression, our studies are focused on the role of the short tandem repeat polymorphism, (GGGGC){sub n}, located in the proximal promoter of the human AHR gene. When luciferase constructs containing varying GGGGC repeats were transfected into cancer cell lines derived from the lung, colon, and breast, the number of GGGGC repeats affected AHR promoter activity. The number of GGGGC repeats was determined in DNA from 327 humans and from 38 samples representing 5 species of non-human primates. In chimpanzees and 3 species of macaques, only (GGGGC){sub 2} alleles were observed; however, in western gorilla, (GGGGC){sub n} alleles with n = 2, 4, 5, 6, 7, and 8 were identified. In all human populations examined, the frequency of (GGGGC){sub n} was n = 4 > 5 ≫ 2, 6. When frequencies of the (GGGGC){sub n} alleles in DNA from patients with lung, colon, or breast cancer were evaluated, the occurrence of (GGGGC){sub 2} was found to be 8-fold more frequent among lung cancer patients in comparison with its incidence in the general population, as represented by New York State neonates. Analysis of matched tumor and non-tumor DNA samples from the same individuals provided no evidence of microsatellite instability. These studies indicate that the (GGGGC){sub n} short tandem repeats are inherited, and that the (GGGGC){sub 2} allele in the AHR proximal promoter region should be further investigated with regard to its potential association with lung cancer susceptibility. - Highlights: • The AHR proximal promoter contains a polymorphism, (GGGGC){sub n}, where n = 4 > 5 ≫ 2, 6 • Matched tumor and non-tumor DNA did not show (GGGGC){sub n} microsatellite instability • AHR promoter activity of a construct with (GGGGC){sub 2} was lower than that of (GGGGC){sub 4} • The frequency of (GGGGC){sub 2} in lung

Characterization of the promoter and upstream activating sequence from the Pseudomonas alcaligenes lipase gene

NARCIS (Netherlands)

Cox, M; Gerritse, G; Dankmeyer, L; Quax, W.J.

2001-01-01

Pseudomonas alcaligenes secretes a lipase with a high pH optimum, which has interesting properties for application in detergents. The expression of the lipase is strongly dependent on the presence of lipids in the growth medium such as soybean oil. The promoter of the gene was characterized and

N-myc downstream-regulated gene 1 promotes oxaliplatin-triggered apoptosis in colorectal cancer cells via enhancing the ubiquitination of Bcl-2.

Science.gov (United States)

Yang, Xiao; Zhu, Fan; Yu, Chaoran; Lu, Jiaoyang; Zhang, Luyang; Lv, Yanfeng; Sun, Jing; Zheng, Minhua

2017-07-18

N-myc downstream-regulated gene1 (NDRG1) has been identified as a potent tumor suppressor gene. The molecular mechanisms of anti-tumor activity of NDRG1 involve its suppressive effects on a variety of tumorigenic signaling pathways. The purpose of this study was to investigate the role of NDRG1 in the apoptosis of colorectal cancer (CRC) cells. We first collected the clinical data of locally advanced rectal cancer (LARC) patients receiving oxaliplatin-based neoadjuvant chemotherapy in our medical center. Correlation analysis revealed that NDRG1 positively associated with the downstaging rates and prognosis of patients. Then, the effects of over-expression and depletion of NDRG1 gene on apoptosis of colorectal cancer were tested in vitro and in vivo. NDRG1 over-expression promoted apoptosis in colorectal cancer cells whereas depletion of NDRG1 resulted in resistance to oxaliplatin treatment. Furthermore, we observed that Bcl-2, a major anti-apoptotic protein, was regulated by NDRG1 at post-transcriptional level. By binding Protein kinase Cα (PKCα), a classical regulating factor of Bcl-2, NDRG1 enhanced the ubiquitination and degradation of Bcl-2, thus promoting apoptosis in CRC cells. In addition, NDRG1 inhibited tumor growth and promoted apoptosis in mouse xenograft model. In conclusion,NDRG1 promotes oxaliplatin-triggered apoptosis in colorectal cancer. Therefore, colorectal cancer patients can be stratified by the expression level of NDRG1. NDRG1-positive patients may benefit from oxaliplatin-containing chemotherapy regimens whereas those with negative NDRG1 expression should avoid the usage of this cytotoxic drug.

Genetic and Epigenetic Tumor Suppressor Gene Silencing are Distinct Molecular Phenotypes Driven by Growth Promoting Mutations in Non small Cell Lung Cancer

International Nuclear Information System (INIS)

Marsit, C. J.; Kelsey, K. T.; Houseman, E. A.; Kelsey, K. T.; Houseman, E. A.; Nelson, H. H.

2008-01-01

Both genetic and epigenetic alterations characterize human non small cell lung cancer (NSCLC), but the biological processes that create or select these alterations remain incompletely investigated. Our hypothesis posits that a roughly reciprocal relationship between the propensity for promoter hyper methylation and a propensity for genetic deletion leads to distinct molecular phenotypes of lung cancer. To test this hypothesis, we examined promoter hyper methylation of 17 tumor suppressor genes, as a marker of epigenetic alteration propensity, and deletion events at the 3p21 region, as a marker of genetic alteration. To model the complex biology between these somatic alterations, we utilized an item response theory model. We demonstrated that tumors exhibiting LOH at greater than 30% of informative alleles in the 3p21 region have a significantly reduced propensity for hyper methylation. At the same time, tumors with activating KRAS mutations showed a significantly increased propensity for hyper methylation of the loci examined, a result similar to what has been observed in colon cancer. These data suggest that NSCLCs have distinct epigenetic or genetic alteration phenotypes acting upon tumor suppressor genes and that mutation of oncogenic growth promoting genes, such as KRAS, is associated with the epigenetic phenotype.

Resistance to BmNPV via overexpression of an exogenous gene controlled by an inducible promoter and enhancer in transgenic silkworm, Bombyx mori.

Directory of Open Access Journals (Sweden)

Liang Jiang

Full Text Available The hycu-ep32 gene of Hyphantria cunea NPV can inhibit Bombyx mori nucleopolyhedrovirus (BmNPV multiplication in co-infected cells, but it is not known whether the overexpression of the hycu-ep32 gene has an antiviral effect in the silkworm, Bombyx mori. Thus, we constructed four transgenic vectors, which were under the control of the 39 K promoter of BmNPV (39 KP, Bombyx mori A4 promoter (A4P, hr3 enhancer of BmNPV combined with 39 KP, and hr3 combined with A4P. Transgenic lines were created via embryo microinjection using practical diapause silkworm. qPCR revealed that the expression level of hycu-ep32 could be induced effectively after BmNPV infection in transgenic lines where hycu-ep32 was controlled by hr3 combined with 39 KP (i.e., HEKG. After oral inoculation of BmNPV with 3 × 10(5 occlusion bodies per third instar, the mortality with HEKG-B was approximately 30% lower compared with the non-transgenic line. The economic characteristics of the transgenic lines remained unchanged. These results suggest that overexpression of an exogenous antiviral gene controlled by an inducible promoter and enhancer is a feasible method for breeding silkworms with a high antiviral capacity.

Genome-wide analysis of promoter architecture in Drosophila melanogaster

Energy Technology Data Exchange (ETDEWEB)

Hoskins, Roger A.; Landolin, Jane M.; Brown, James B.; Sandler, Jeremy E.; Takahashi, Hazuki; Lassmann, Timo; Yu, Charles; Booth, Benjamin W.; Zhang, Dayu; Wan, Kenneth H.; Yang, Li; Boley, Nathan; Andrews, Justen; Kaufman, Thomas C.; Graveley, Brenton R.; Bickel, Peter J.; Carninci, Piero; Carlson, Joseph W.; Celniker, Susan E.

2010-10-20

Core promoters are critical regions for gene regulation in higher eukaryotes. However, the boundaries of promoter regions, the relative rates of initiation at the transcription start sites (TSSs) distributed within them, and the functional significance of promoter architecture remain poorly understood. We produced a high-resolution map of promoters active in the Drosophila melanogaster embryo by integrating data from three independent and complementary methods: 21 million cap analysis of gene expression (CAGE) tags, 1.2 million RNA ligase mediated rapid amplification of cDNA ends (RLMRACE) reads, and 50,000 cap-trapped expressed sequence tags (ESTs). We defined 12,454 promoters of 8037 genes. Our analysis indicates that, due to non-promoter-associated RNA background signal, previous studies have likely overestimated the number of promoter-associated CAGE clusters by fivefold. We show that TSS distributions form a complex continuum of shapes, and that promoters active in the embryo and adult have highly similar shapes in 95% of cases. This suggests that these distributions are generally determined by static elements such as local DNA sequence and are not modulated by dynamic signals such as histone modifications. Transcription factor binding motifs are differentially enriched as a function of promoter shape, and peaked promoter shape is correlated with both temporal and spatial regulation of gene expression. Our results contribute to the emerging view that core promoters are functionally diverse and control patterning of gene expression in Drosophila and mammals.

Methylated Host Cell Gene Promoters and Human Papillomavirus Type 16 and 18 Predicting Cervical Lesions and Cancer.

Directory of Open Access Journals (Sweden)

Nina Milutin Gašperov

Full Text Available Change in the host and/or human papillomavirus (HPV DNA methylation profile is probably one of the main factors responsible for the malignant progression of cervical lesions to cancer. To investigate those changes we studied 173 cervical samples with different grades of cervical lesion, from normal to cervical cancer. The methylation status of nine cellular gene promoters, CCNA1, CDH1, C13ORF18, DAPK1, HIC1, RARβ2, hTERT1, hTERT2 and TWIST1, was investigated by Methylation Specific Polymerase Chain Reaction (MSP. The methylation of HPV18 L1-gene was also investigated by MSP, while the methylated cytosines within four regions, L1, 5'LCR, enhancer, and promoter of the HPV16 genome covering 19 CpG sites were evaluated by bisulfite sequencing. Statistically significant methylation biomarkers distinguishing between cervical precursor lesions from normal cervix were primarily C13ORF18 and secondly CCNA1, and those distinguishing cervical cancer from normal or cervical precursor lesions were CCNA1, C13ORF18, hTERT1, hTERT2 and TWIST1. In addition, the methylation analysis of individual CpG sites of the HPV16 genome in different sample groups, notably the 7455 and 7694 sites, proved to be more important than the overall methylation frequency. The majority of HPV18 positive samples contained both methylated and unmethylated L1 gene, and samples with L1-gene methylated forms alone had better prognosis when correlated with the host cell gene promoters' methylation profiles. In conclusion, both cellular and viral methylation biomarkers should be used for monitoring cervical lesion progression to prevent invasive cervical cancer.

Cis-acting regulatory sequences promote high-frequency gene conversion between repeated sequences in mammalian cells.

Science.gov (United States)

Raynard, Steven J; Baker, Mark D

2004-01-01

In mammalian cells, little is known about the nature of recombination-prone regions of the genome. Previously, we reported that the immunoglobulin heavy chain (IgH) mu locus behaved as a hotspot for mitotic, intrachromosomal gene conversion (GC) between repeated mu constant (Cmu) regions in mouse hybridoma cells. To investigate whether elements within the mu gene regulatory region were required for hotspot activity, gene targeting was used to delete a 9.1 kb segment encompassing the mu gene promoter (Pmu), enhancer (Emu) and switch region (Smu) from the locus. In these cell lines, GC between the Cmu repeats was significantly reduced, indicating that this 'recombination-enhancing sequence' (RES) is necessary for GC hotspot activity at the IgH locus. Importantly, the RES fragment stimulated GC when appended to the same Cmu repeats integrated at ectopic genomic sites. We also show that deletion of Emu and flanking matrix attachment regions (MARs) from the RES abolishes GC hotspot activity at the IgH locus. However, no stimulation of ectopic GC was observed with the Emu/MARs fragment alone. Finally, we provide evidence that no correlation exists between the level of transcription and GC promoted by the RES. We suggest a model whereby Emu/MARS enhances mitotic GC at the endogenous IgH mu locus by effecting chromatin modifications in adjacent DNA.

Promoter analysis of the Chilo iridescent virus DNA polymerase and major capsid protein genes

NARCIS (Netherlands)

Nalcacioglu, R.; Marks, H.; Vlak, J.M.; Demirbag, Z.; Oers, van M.M.

2003-01-01

The DNA polymerase (DNApol) and major capsid protein (MCP) genes were used as models to study promoter activity in Chilo iridescent virus (CIV). Infection of Bombyx mori SPC-BM-36 cells in the presence of inhibitors of DNA or protein synthesis showed that DNApol, as well as helicase, is an

Promoter for the late gene encoding Vp5 of herpes simplex virus type 1 is recognized by cell extracts derived from uninfected cells

International Nuclear Information System (INIS)

Chisholm, G.E.; Summers, W.C.

1986-01-01

The ability of whole-cell extracts from unidentified HeLa cells to recognize the promoter for the herpes simplex virus type 1 late gene encoding the major capsid protein Vp5 was investigated by using both in vitro transcriptional and S1 nuclease protection analysis. This gene promoter was recognized by the cell extracts and produced abundant amounts of transcript in the absence of any other virus-encoded factors. This transcript was shown to arise, in vitro, from specific initiation at or very near the physiological mRNA start site. Thus, it appears that cell extracts from uninfected HeLa cells can efficiently recognize both early- and late-gene promoters

Promoter characterization and genomic organization of the human X11β gene APBA2.

LENUS (Irish Health Repository)

Hao, Yan

2012-02-15

Overexpression of neuronal adaptor protein X11β has been shown to decrease the production of amyloid-β, a toxic peptide deposited in Alzheimer\\'s disease brains. Therefore, manipulation of the X11β level may represent a potential therapeutic strategy for Alzheimer\\'s disease. As X11β expression can be regulated at the transcription level, we determined the genomic organization and the promoter of the human X11β gene, amyloid β A4 precursor protein-binding family A member 2 (APBA2). By RNA ligase-mediated rapid amplification of cDNA ends, a single APBA2 transcription start site and the complete sequence of exon 1 were identified. The APBA2 promoter was located upstream of exon 1 and was more active in neurons. The core promoter contains several CpG dinucleotides, and was strongly suppressed by DNA methylation. In addition, mutagenesis analysis revealed a putative Pax5-binding site within the promoter. Together, APBA2 contains a potent neuronal promoter whose activity may be regulated by DNA methylation and Pax5.

The architecture of mammalian ribosomal protein promoters

Directory of Open Access Journals (Sweden)

Perry Robert P

2005-02-01

Full Text Available Abstract Background Mammalian ribosomes contain 79 different proteins encoded by widely scattered single copy genes. Coordinate expression of these genes at transcriptional and post-transcriptional levels is required to ensure a roughly equimolar accumulation of ribosomal proteins. To date, detailed studies of only a very few ribosomal protein (rp promoters have been made. To elucidate the general features of rp promoter architecture, I made a detailed sequence comparison of the promoter regions of the entire set of orthologous human and mouse rp genes. Results A striking evolutionarily conserved feature of most rp genes is the separation by an intron of the sequences involved in transcriptional and translational regulation from the sequences with protein encoding function. Another conserved feature is the polypyrimidine initiator, which conforms to the consensus (Y2C+1TY(T2(Y3. At least 60 % of the rp promoters contain a largely conserved TATA box or A/T-rich motif, which should theoretically have TBP-binding capability. A remarkably high proportion of the promoters contain conserved binding sites for transcription factors that were previously implicated in rp gene expression, namely upstream GABP and Sp1 sites and downstream YY1 sites. Over 80 % of human and mouse rp genes contain a transposable element residue within 900 bp of 5' flanking sequence; very little sequence identity between human and mouse orthologues was evident more than 200 bp upstream of the transcriptional start point. Conclusions This analysis has provided some valuable insights into the general architecture of mammalian rp promoters and has identified parameters that might coordinately regulate the transcriptional activity of certain subsets of rp genes.

Leptin promoter gene polymorphism on -2549 position decreases plasma leptin and increases appetite in normal weight volunteers

Directory of Open Access Journals (Sweden)

Sandra Bragança Coelho

2014-05-01

Full Text Available Introduction: Investigate whether polymorphism in the promoter region encoding leptin and leptin receptor gene, in normal weight individuals, affects hormonal and appetite responses to peanuts.Materials and methods: Appetite, anthropometric indices, body composition, physical activity, dietary intake and leptin, ghrelin and insulin levels were monitored. Polymorphism analyses were also carried out.Results: None of the treatments led to statistical differences in the analyzed hormones. No polymorphism was found for leptin receptor gene, while for leptin gene, 50% of the volunteers presented one polymorphic allele and 13% presented both polymorphic alleles. These last ones presented lower body fat mass, leptin and ghrelin plasma concentrations, and fullness rates. They also presented higher hunger, desire to eat, and desire to eat sweet and salty foods.Conclusions: Peanut did not affect appetite and presented no different hormonal responses, compared to other foods studied. Polymorphic allele carriers in both alleles presented higher probability to develop obesity. However, the magnitude of this probability could not be measured.

Gene expression results in lipopolysaccharide-stimulated monocytes depend significantly on the choice of reference genes

Directory of Open Access Journals (Sweden)

Øvstebø Reidun

2010-05-01

Full Text Available Abstract Background Gene expression in lipopolysaccharide (LPS-stimulated monocytes is mainly studied by quantitative real-time reverse transcription PCR (RT-qPCR using GAPDH (glyceraldehyde 3-phosphate dehydrogenase or ACTB (beta-actin as reference gene for normalization. Expression of traditional reference genes has been shown to vary substantially under certain conditions leading to invalid results. To investigate whether traditional reference genes are stably expressed in LPS-stimulated monocytes or if RT-qPCR results are dependent on the choice of reference genes, we have assessed and evaluated gene expression stability of twelve candidate reference genes in this model system. Results Twelve candidate reference genes were quantified by RT-qPCR in LPS-stimulated, human monocytes and evaluated using the programs geNorm, Normfinder and BestKeeper. geNorm ranked PPIB (cyclophilin B, B2M (beta-2-microglobulin and PPIA (cyclophilin A as the best combination for gene expression normalization in LPS-stimulated monocytes. Normfinder suggested TBP (TATA-box binding protein and B2M as the best combination. Compared to these combinations, normalization using GAPDH alone resulted in significantly higher changes of TNF-α (tumor necrosis factor-alpha and IL10 (interleukin 10 expression. Moreover, a significant difference in TNF-α expression between monocytes stimulated with equimolar concentrations of LPS from N. meningitides and E. coli, respectively, was identified when using the suggested combinations of reference genes for normalization, but stayed unrecognized when employing a single reference gene, ACTB or GAPDH. Conclusions Gene expression levels in LPS-stimulated monocytes based on RT-qPCR results differ significantly when normalized to a single gene or a combination of stably expressed reference genes. Proper evaluation of reference gene stabiliy is therefore mandatory before reporting RT-qPCR results in LPS-stimulated monocytes.

Functional evolution in the plant SQUAMOSA-PROMOTER BINDING PROTEIN-LIKE (SPL gene family

Directory of Open Access Journals (Sweden)

Jill Christine Preston

2013-04-01

Full Text Available The SQUAMOSA-PROMOTER BINDING PROTEIN-LIKE (SPL family of transcription factors is functionally diverse, controlling a number of fundamental aspects of plant growth and development, including vegetative phase change, flowering time, branching, and leaf initiation rate. In natural plant populations, variation in flowering time and shoot architecture have major consequences for fitness. Likewise, in crop species, variation in branching and developmental rate impact biomass and yield. Thus, studies aimed at dissecting how the various functions are partitioned among different SPL genes in diverse plant lineages are key to providing insight into the genetic basis of local adaptation and have already garnered attention by crop breeders. Here we use phylogenetic reconstruction to reveal nine major SPL gene lineages, each of which is described in terms of function and diversification. To assess evidence for ancestral and derived functions within each SPL gene lineage, we use ancestral character state reconstructions. Our analyses suggest an emerging pattern of sub-functionalization, neo-functionalization, and possible convergent evolution following both ancient and recent gene duplication. Based on these analyses we suggest future avenues of research that may prove fruitful for elucidating the importance of SPL gene evolution in plant growth and development.

Genome-wide screening identifies Plasmodium chabaudi-induced modifications of DNA methylation status of Tlr1 and Tlr6 gene promoters in liver, but not spleen, of female C57BL/6 mice.

Science.gov (United States)

Al-Quraishy, Saleh; Dkhil, Mohamed A; Abdel-Baki, Abdel Azeem S; Delic, Denis; Santourlidis, Simeon; Wunderlich, Frank

2013-11-01

Epigenetic reprogramming of host genes via DNA methylation is increasingly recognized as critical for the outcome of diverse infectious diseases, but information for malaria is not yet available. Here, we investigate the effect of blood-stage malaria of Plasmodium chabaudi on the DNA methylation status of host gene promoters on a genome-wide scale using methylated DNA immunoprecipitation and Nimblegen microarrays containing 2,000 bp oligonucleotide features that were split into -1,500 to -500 bp Ups promoters and -500 to +500 bp Cor promoters, relative to the transcription site, for evaluation of differential DNA methylation. Gene expression was analyzed by Agilent and Affymetrix microarray technology. Challenging of female C57BL/6 mice with 10(6) P. chabaudi-infected erythrocytes resulted in a self-healing outcome of infections with peak parasitemia on day 8 p.i. These infections induced organ-specific modifications of DNA methylation of gene promoters. Among the 17,354 features on Nimblegen arrays, only seven gene promoters were identified to be hypermethylated in the spleen, whereas the liver exhibited 109 hyper- and 67 hypomethylated promoters at peak parasitemia in comparison with non-infected mice. Among the identified genes with differentially methylated Cor-promoters, only the 7 genes Pigr, Ncf1, Klkb1, Emr1, Ndufb11, and Tlr6 in the liver and Apol6 in the spleen were detected to have significantly changed their expression. Remarkably, the Cor promoter of the toll-like receptor Tlr6 became hypomethylated and Tlr6 expression increased by 3.4-fold during infection. Concomitantly, the Ups promoter of the Tlr1 was hypermethylated, but Tlr1 expression also increased by 11.3-fold. TLR6 and TLR1 are known as auxillary receptors to form heterodimers with TLR2 in plasma membranes of macrophages, which recognize different pathogen-associated molecular patterns (PAMPs), as, e.g., intact 3-acyl and sn-2-lyso-acyl glycosylphosphatidylinositols of P. falciparum

Dragon (repulsive guidance molecule b, RGMb) is a novel gene that promotes colorectal cancer growth.

Science.gov (United States)

Shi, Ying; Chen, Guo-Bin; Huang, Xiao-Xiao; Xiao, Chuan-Xing; Wang, Huan-Huan; Li, Ye-Sen; Zhang, Jin-Fang; Li, Shao; Xia, Yin; Ren, Jian-Lin; Guleng, Bayasi

2015-08-21

Colorectal cancer (CRC) is one of the most commonly diagnosed cancers and a major cause of cancer death. However, the molecular mechanisms underlying CRC initiation, growth and metastasis are poorly understood. Dragon (RGMb), a member of the repulsive guidance molecule (RGM) family, has been recently identified as a co-receptor for bone morphogenetic protein (BMP) signaling, but the role of Dragon in CRC development is undefined. Here, we show that Dragon expression was increased in colon cancer tissues compared to control tissues in CAC mouse model and in human patients. Dragon promoted proliferation of CT26.WT and CMT93 colon cancer cells and accelerated tumor growth in the xenograft mouse model. Dragon's action on colon cancer development was mediated via the BMP4-Smad1/5/8 and Erk1/2 pathways. Therefore, our results have revealed that Dragon is a novel gene that promotes CRC growth through the BMP pathway. Dragon may be exploited as a potential therapeutic target for CRC treatment.

Upland cotton gene GhFPF1 confers promotion of flowering time and shade-avoidance responses in Arabidopsis thaliana.

Directory of Open Access Journals (Sweden)

Xiaoyan Wang

Full Text Available Extensive studies on floral transition in model species have revealed a network of regulatory interactions between proteins that transduce and integrate developmental and environmental signals to promote or inhibit the transition to flowering. Previous studies indicated FLOWERING PROMOTING FACTOR 1 (FPF1 gene was involved in the promotion of flowering, but the molecular mechanism was still unclear. Here, FPF1 homologous sequences were screened from diploid Gossypium raimondii L. (D-genome, n = 13 and Gossypium arboreum L. genome (A-genome, n = 13 databases. Orthologous genes from the two species were compared, suggesting that distinctions at nucleic acid and amino acid levels were not equivalent because of codon degeneracy. Six FPF1 homologous genes were identified from the cultivated allotetraploid Gossypium hirsutum L. (AD-genome, n = 26. Analysis of relative transcripts of the six genes in different tissues revealed that this gene family displayed strong tissue-specific expression. GhFPF1, encoding a 12.0-kDa protein (Accession No: KC832319 exerted more transcripts in floral apices of short-season cotton, hinting that it could be involved in floral regulation. Significantly activated APETALA 1 and suppressed FLOWERING LOCUS C expression were induced by over-expression of GhFPF1 in the Arabidopsis Columbia-0 ecotype. In addition, transgenic Arabidopsis displayed a constitutive shade-avoiding phenotype that is characterized by long hypocotyls and petioles, reduced chlorophyll content, and early flowering. We propose that GhFPF1 may be involved in flowering time control and shade-avoidance responses.

A comparative analysis of constitutive promoters located in adeno-associated viral vectors.

Directory of Open Access Journals (Sweden)

Lkhagvasuren Damdindorj

Full Text Available The properties of constitutive promoters within adeno-associated viral (AAV vectors have not yet been fully characterized. In this study, AAV vectors, in which enhanced GFP expression was directed by one of the six constitutive promoters (human β-actin, human elongation factor-1α, chicken β-actin combined with cytomegalovirus early enhancer, cytomegalovirus (CMV, simian virus 40, and herpes simplex virus thymidine kinase, were constructed and introduced into the HCT116, DLD-1, HT-1080, and MCF-10A cell lines. Quantification of GFP signals in infected cells demonstrated that the CMV promoter produced the highest GFP expression in the six promoters and maintained relatively high GFP expression for up to eight weeks after infection of HCT116, DLD-1, and HT-1080. Exogenous human CDKN2A gene expression was also introduced into DLD-1 and MCF-10A in a similar pattern by using AAV vectors bearing the human β-actin and the CMV promoters. The six constitutive promoters were subsequently placed upstream of the neomycin resistance gene within AAV vectors, and HCT116, DLD-1, and HT-1080 were infected with the resulting vectors. Of the six promoters, the CMV promoter produced the largest number of G418-resistant colonies in all three cell lines. Because AAV vectors have been frequently used as a platform to construct targeting vectors that permit gene editing in human cell lines, we lastly infected the three cell lines with AAV-based targeting vectors against the human PIGA gene in which one of the six promoters regulate the neomycin resistance gene. This assay revealed that the CMV promoter led to the lowest PIGA gene targeting efficiency in the investigated promoters. These results provide a clue to the identification of constitutive promoters suitable to express exogenous genes with AAV vectors, as well as those helpful to conduct efficient gene targeting using AAV-based targeting vectors in human cell lines.

A shared promoter region suggests a common ancestor for the human VCX/Y, SPANX, and CSAG gene families and the murine CYPT family

DEFF Research Database (Denmark)

Hansen, Martin A; Nielsen, John E; Retelska, Dorota

2008-01-01

, sequences corresponding to the shared promoter region of the CYPT family were identified at 39 loci. Most loci were located immediately upstream of genes belonging to the VCX/Y, SPANX, or CSAG gene families. Sequence comparison of the loci revealed a conserved CYPT promoter-like (CPL) element featuring TATA...... cell types. The genomic regions harboring the gene families were rich in direct and inverted segmental duplications (SD), which may facilitate gene conversion and rapid evolution. The conserved CPL and the common expression profiles suggest that the human VCX/Y, SPANX, and CSAG2 gene families together......Many testis-specific genes from the sex chromosomes are subject to rapid evolution, which can make it difficult to identify murine genes in the human genome. The murine CYPT gene family includes 15 members, but orthologs were undetectable in the human genome. However, using refined homology search...

Murine homeobox-containing gene, Msx-1: analysis of genomic organization, promoter structure, and potential autoregulatory cis-acting elements.

Science.gov (United States)

Kuzuoka, M; Takahashi, T; Guron, C; Raghow, R

1994-05-01

Detailed molecular organization of the coding and upstream regulatory regions of the murine homeodomain-containing gene, Msx-1, is reported. The protein-encoding portion of the gene is contained in two exons, 590 and 1214 bp in length, separated by a 2107-bp intron; the homeodomain is located in the second exon. The two-exon organization of the murine Msx-1 gene resembles a number of other homeodomain-containing genes. The 5'-(GTAAGT) and 3'-(CCCTAG) splicing junctions and the mRNA polyadenylation signal (UAUAA) of the murine Msx-1 gene are also characteristic of other vertebrate genes. By nuclease protection and primer extension assays, the start of transcription of the Msx-1 gene was located 256 bp upstream of the first AUG. Computer analysis of the promoter proximal 1280-bp sequence revealed a number of potentially important cis-regulatory sequences; these include the recognition elements for Ap-1, Ap-2, Ap-3, Sp-1, a possible binding site for RAR:RXR, and a number of TCF-1 consensus motifs. Importantly, a perfect reverse complement of (C/G)TTAATTG, which was recently shown to be an optimal binding sequence for the homeodomain of Msx-1 protein (K.M. Catron, N. Iler, and C. Abate (1993) Mol. Cell. Biol. 13:2354-2365), was also located in the murine Msx-1 promoter. Binding of bacterially expressed Msx-1 homeodomain polypeptide to Msx-1-specific oligonucleotide was experimentally demonstrated, raising a distinct possibility of autoregulation of this developmentally regulated gene.

Genome-wide prediction and functional validation of promoter motifs regulating gene expression in spore and infection stages of Phytophthora infestans.

Directory of Open Access Journals (Sweden)

Sourav Roy

2013-03-01

Full Text Available Most eukaryotic pathogens have complex life cycles in which gene expression networks orchestrate the formation of cells specialized for dissemination or host colonization. In the oomycete Phytophthora infestans, the potato late blight pathogen, major shifts in mRNA profiles during developmental transitions were identified using microarrays. We used those data with search algorithms to discover about 100 motifs that are over-represented in promoters of genes up-regulated in hyphae, sporangia, sporangia undergoing zoosporogenesis, swimming zoospores, or germinated cysts forming appressoria (infection structures. Most of the putative stage-specific transcription factor binding sites (TFBSs thus identified had features typical of TFBSs such as position or orientation bias, palindromy, and conservation in related species. Each of six motifs tested in P. infestans transformants using the GUS reporter gene conferred the expected stage-specific expression pattern, and several were shown to bind nuclear proteins in gel-shift assays. Motifs linked to the appressoria-forming stage, including a functionally validated TFBS, were over-represented in promoters of genes encoding effectors and other pathogenesis-related proteins. To understand how promoter and genome architecture influence expression, we also mapped transcription patterns to the P. infestans genome assembly. Adjacent genes were not typically induced in the same stage, including genes transcribed in opposite directions from small intergenic regions, but co-regulated gene pairs occurred more than expected by random chance. These data help illuminate the processes regulating development and pathogenesis, and will enable future attempts to purify the cognate transcription factors.

Regulatory elements in vivo in the promoter of the abscisic acid responsive gene rab17 from maize.

Science.gov (United States)

Busk, P K; Jensen, A B; Pagès, M

1997-06-01

The rab17 gene from maize is transcribed in late embryonic development and is responsive to abscisic acid and water stress in embryo and vegetative tissues. In vivo footprinting and transient transformation of rab17 were performed in embryos and vegetative tissues to characterize the cis-elements involved in regulation of the gene. By in vivo footprinting, protein binding was observed to nine elements in the promoter, which correspond to five putative ABREs (abscisic acid responsive elements) and four other sequences. The footprints indicated that distinct proteins interact with these elements in the two developmental stages. In transient transformation, six of the elements were important for high level expression of the rab17 promoter in embryos, whereas only three elements were important in leaves. The cis-acting sequences can be divided in embryo-specific, ABA-specific and leaf-specific elements on the basis of protein binding and the ability to confer expression of rab17. We found one positive, new element, called GRA, with the sequence CACTGGCCGCCC. This element was important for transcription in leaves but not in embryos. Two other non-ABRE elements that stimulated transcription from the rab17 promoter resemble previously described abscisic acid and drought-inducible elements. There were differences in protein binding and function of the five ABREs in the rab17 promoter. The possible reasons for these differences are discussed. The in vivo data obtained suggest that an embryo-specific pathway regulates transcription of the rab genes during development, whereas another pathway is responsible for induction in response to ABA and drought in vegetative tissues.

Transactivation of the proenkephalin gene promoter by the Tax sub 1 protein of human T-cell lymphotropic virus type I

Energy Technology Data Exchange (ETDEWEB)

Joshi, J.B. (National Heart, Lung, and Blood Inst., Bethesda, MD (United States)); Dave, H.P.G. (National Inst. of Health, Bethesda, MD (United States))

1992-02-01

Human T-cell lymphotropic virus type I (HTLV-I), an etiologic agent for adult T-cell leukemia, is strongly associated with certain neurological diseases. The HTLV-I genome encodes a protein, Tax{sub 1}, that transactivates viral gene transcription. CD4-positive T helper lymphocytes express the proenkephalin gene, and enkephalins have been implicated as neuroimmunomodulators. The authors have investigated the effect of Tax{sub 1} on the proenkephalin gene promoter in C6 rat glioma cells and demonstrated its transactivation. Analysis using 5{prime} deletion mutants of the promoter region showed that sequences upstream of base pair - 190 are necessary for maximal transactivation. Forskolin, a cAMP modulator, synergistically increased Tax{sub 1}-mediated transactivation of the proenkephalin promoter. Neither Tax{sub 1} transactivation alone nor Tax{sub 1}/cAMP synergism exclusively involved cAMP-responsive elements. Endogenous proenkephalin gene expression increased in Tax{sub 1}-expressing C6 cells. Since HTLV-I infects lymphocytes, which express proenkephalin mRNA, Tax{sub 1} transregulation of proenkephalin expression may provide bidirectional communication between the nervous and immune systems in HTLV-I-related diseases.

ADAM33 gene silencing by promoter hypermethylation as a molecular marker in breast invasive lobular carcinoma

International Nuclear Information System (INIS)

Seniski, Gerusa G; Zanata, Silvio M; Costa, Fabrício F; Klassen, Giseli; Camargo, Anamaria A; Ierardi, Daniela F; Ramos, Edneia AS; Grochoski, Mariana; Ribeiro, Enilze SF; Cavalli, Iglenir J; Pedrosa, Fabio O; Souza, Emanuel M de

2009-01-01

ADAM33 protein is a member of the family of transmembrane glycoproteins composed of multidomains. ADAM family members have different activities, such as proteolysis and adhesion, making them good candidates to mediate the extracellular matrix remodelling and changes in cellular adhesion that characterise certain pathologies and cancer development. It was reported that one family member, ADAM23, is down-regulated by promoter hypermethylation. This seems to correlate with tumour progression and metastasis in breast cancer. In this study, we explored the involvement of ADAM33, another ADAM family member, in breast cancer. First, we analysed ADAM33 expression in breast tumour cell lines by RT-PCR and western blotting. We also used 5-aza-2'-deoxycytidine (5azadCR) treatment and DNA bisulphite sequencing to study the promoter methylation of ADAM33 in breast tumour cell lines. We evaluated ADAM33 methylation in primary tumour samples by methylation specific PCR (MSP). Finally, ADAM33 promoter hypermethylation was correlated with clinicopathological data using the chi-square test and Fisher's exact test. The expression analysis of ADAM33 in breast tumour cell lines by RT-PCR revealed gene silencing in 65% of tumour cell lines. The corresponding lack of ADAM33 protein was confirmed by western blotting. We also used 5-aza-2'-deoxycytidine (5-aza-dCR) demethylation and bisulphite sequencing methodologies to confirm that gene silencing is due to ADAM33 promoter hypermethylation. Using MSP, we detected ADAM33 promoter hypermethylation in 40% of primary breast tumour samples. The correlation between methylation pattern and patient's clinicopathological data was not significantly associated with histological grade; tumour stage (TNM); tumour size; ER, PR or ERBB2 status; lymph node status; metastasis or recurrence. Methylation frequency in invasive lobular carcinoma (ILC) was 76.2% compared with 25.5% in invasive ductal carcinoma (IDC), and this difference was

In silico analysis and DHPLC screening strategy identifies novel apoptotic gene targets of aberrant promoter hypermethylation in prostate cancer.

LENUS (Irish Health Repository)

Murphy, Therese M

2011-01-01

Aberrant DNA methylation has been implicated as a key survival mechanism in cancer, whereby promoter hypermethylation silences genes essential for many cellular processes including apoptosis. Limited data is available on the methylation profile of apoptotic genes in prostate cancer (CaP). The aim of this study was to profile methylation of apoptotic-related genes in CaP using denaturing high performance liquid chromatography (DHPLC).

Internal radiotherapy of liver cancer with rat hepato-carcinoma-intestine-pancreas gene as a liver tumor-specific promoter

Energy Technology Data Exchange (ETDEWEB)

Herve, J.; Cunha, A. Sa; Liu, B.; Valogne, Y.; Longuet, M.; Bregerie, O.; Guettier, C.; Samuel, D.; Brechot, C.; Faivre, J. [Hop Paul Brousse, INSERM, Hepatobiliary Ctr, U785, F-94800 Villejuif (France); Herve, J.; Cunha, A. Sa; Liu, B.; Valogne, Y.; Longuet, M.; Bregerie, O.; Guettier, C.; Samuel, D.; Brechot, C.; Faivre, J. [Univ Paris Sud, Fac Med, F-94800 Villejuif (France); Boisgard, R.; Tavitian, B. [INSERM, U803, F-91400 Orsay (France); Boisgard, R.; Tavitian, B. [CEA, Serv Hosp Frederic Joliot, Lab Imagerie Mol Expt, F-91400 Orsay (France); Roux, J.; Cales, P. [Univ Angers, UPRES EA 3859, Lab Hemodynam Interact Fibrose et Invas Tumorale H, Angers (France); Clerc, J. [Hop Cochin, AP HP, Dept Nucl Med, F-75014 Paris (France)

2008-07-01

The hepato-carcinoma-intestine-pancreas (HIP) gene, also called pancreatitis-associated protein-1 (PAP1) or Reg III {alpha}, is activated in most human hepatocellular carcinomas (HCCs) but not in normal liver, which suggests that HIP regulatory sequence could be used as efficient liver tumor-specific promoters to express a therapeutic polynucleotide in liver cancer. The sodium iodide sym-porter (NIS), which has recognized therapeutic and reporter gene properties, is appropriate to evaluate the transcriptional strength and specificity of the HIP promoter in HCC. For this purpose, we constructed a recombinant rat HIP-NIS adeno-viral vector (AdrHIP-NIS), and evaluated its performance as a mediator of selective radio-iodide uptake in tumor hepatocytes. Western blot, immunofluorescence, and iodide uptake assays were performed in AdrHIP-NIS-infected primary hepatocytes and transformed hepatic and non-hepatic cells. Nuclear imaging, tissue counting and immuno-histo-chemistry were performed in normal and HCC-bearing Wistar rats infected with AdrHIP-NIS intra-tumorally or via the hepatic artery. In AdrHIP-NIS-infected transformed hepatic cells, functional NIS was strongly expressed, as in cells infected with a cytomegalovirus-NIS vector. No NIS expression was found in AdrHIP-NIS-infected normal hepatocytes or transformed non-hepatic cells. In rats bearing multi-nodular HCC, AdrHIP-NIS triggered functional NIS expression that was preferential in tumor hepatocytes. Administration of 18 mCi of {sup 131}I resulted in the destruction of AdrHIP-NIS-injected nodules. This study has identified the rHIP regulatory sequence as a potent liver tumor-specific promoter for the transfer of therapeutic genes, and AdrHIP-NIS-mediated. {sup 131}I therapy as a valuable option for the treatment of multi-nodular HCC. (authors)

Internal radiotherapy of liver cancer with rat hepato-carcinoma-intestine-pancreas gene as a liver tumor-specific promoter

International Nuclear Information System (INIS)

Herve, J.; Cunha, A. Sa; Liu, B.; Valogne, Y.; Longuet, M.; Bregerie, O.; Guettier, C.; Samuel, D.; Brechot, C.; Faivre, J.; Herve, J.; Cunha, A. Sa; Liu, B.; Valogne, Y.; Longuet, M.; Bregerie, O.; Guettier, C.; Samuel, D.; Brechot, C.; Faivre, J.; Boisgard, R.; Tavitian, B.; Boisgard, R.; Tavitian, B.; Roux, J.; Cales, P.; Clerc, J.

2008-01-01

The hepato-carcinoma-intestine-pancreas (HIP) gene, also called pancreatitis-associated protein-1 (PAP1) or Reg III α, is activated in most human hepatocellular carcinomas (HCCs) but not in normal liver, which suggests that HIP regulatory sequence could be used as efficient liver tumor-specific promoters to express a therapeutic polynucleotide in liver cancer. The sodium iodide sym-porter (NIS), which has recognized therapeutic and reporter gene properties, is appropriate to evaluate the transcriptional strength and specificity of the HIP promoter in HCC. For this purpose, we constructed a recombinant rat HIP-NIS adeno-viral vector (AdrHIP-NIS), and evaluated its performance as a mediator of selective radio-iodide uptake in tumor hepatocytes. Western blot, immunofluorescence, and iodide uptake assays were performed in AdrHIP-NIS-infected primary hepatocytes and transformed hepatic and non-hepatic cells. Nuclear imaging, tissue counting and immuno-histo-chemistry were performed in normal and HCC-bearing Wistar rats infected with AdrHIP-NIS intra-tumorally or via the hepatic artery. In AdrHIP-NIS-infected transformed hepatic cells, functional NIS was strongly expressed, as in cells infected with a cytomegalovirus-NIS vector. No NIS expression was found in AdrHIP-NIS-infected normal hepatocytes or transformed non-hepatic cells. In rats bearing multi-nodular HCC, AdrHIP-NIS triggered functional NIS expression that was preferential in tumor hepatocytes. Administration of 18 mCi of 131 I resulted in the destruction of AdrHIP-NIS-injected nodules. This study has identified the rHIP regulatory sequence as a potent liver tumor-specific promoter for the transfer of therapeutic genes, and AdrHIP-NIS-mediated. 131 I therapy as a valuable option for the treatment of multi-nodular HCC. (authors)

ATA homozigosity in the IL-10 gene promoter is a risk factor for schizophrenia in Spanish females: a case control study

Directory of Open Access Journals (Sweden)

Fernandez-Piqueras Jose

2011-06-01

Full Text Available Abstract Background Three IL-10 gene promoter single nucleotide polymorphisms -1082G > A, -819C > T and -592C > A and the haplotypes they define in Caucasians, GCC, ACC, ATA, associated with different IL-10 production rates, have been linked to schizophrenia in some populations with conflicting results. On the basis of the evidence of the sex-dependent effect of certain genes in many complex diseases, we conducted a sex-stratified case-control association study to verify the linkage of the IL-10 gene promoter SNPs and haplotypes with schizophrenia and the possible sex-specific genetic effect in a Spanish schizophrenic population. Methods 241 DSM-IV diagnosed Spanish schizophrenic patients and 435 ethnically matched controls were genotyped for -1082G > A and -592C > A SNPs. Chi squared tests were performed to assess for genetic association of alleles, genotypes and haplotypes with the disease. Results The -1082A allele (p = 0.027, A/A (p = 0.008 and ATA/ATA (p = 0.003 genotypes were significantly associated with schizophrenia in females while neither allelic nor genotypic frequencies reached statistical significance in the male population. Conclusions Our results highlight the hypothesis of an imbalance towards an inflammatory syndrome as the immune abnormality of schizophrenia. Anyway, a better understanding of the involvement of the immune system would imply the search of immune abnormalities in endophenotypes in whose sex and ethnicity might be differential factors. It also reinforces the need of performing complex gene studies based on multiple cytokine SNPs, including anti and pro-inflammatory, to clarify the immune system abnormalities direction in the etiology of schizophrenia.

Engineered Promoters for Potent Transient Overexpression.

Directory of Open Access Journals (Sweden)

Dan Y Even

Full Text Available The core promoter, which is generally defined as the region to which RNA Polymerase II is recruited to initiate transcription, plays a pivotal role in the regulation of gene expression. The core promoter consists of different combinations of several short DNA sequences, termed core promoter elements or motifs, which confer specific functional properties to each promoter. Earlier studies that examined the ability to modulate gene expression levels via the core promoter, led to the design of strong synthetic core promoters, which combine different core elements into a single core promoter. Here, we designed a new core promoter, termed super core promoter 3 (SCP3, which combines four core promoter elements (the TATA box, Inr, MTE and DPE into a single promoter that drives prolonged and potent gene expression. We analyzed the effect of core promoter architecture on the temporal dynamics of reporter gene expression by engineering EGFP expression vectors that are driven by distinct core promoters. We used live cell imaging and flow cytometric analyses in different human cell lines to demonstrate that SCPs, particularly the novel SCP3, drive unusually strong long-term EGFP expression. Importantly, this is the first demonstration of long-term expression in transiently transfected mammalian cells, indicating that engineered core promoters can provide a novel non-viral strategy for biotechnological as well as gene-therapy-related applications that require potent expression for extended time periods.

Gene promoter methylation and DNA repair capacity in monozygotic twins with discordant smoking habits.

Science.gov (United States)

Ottini, Laura; Rizzolo, Piera; Siniscalchi, Ester; Zijno, Andrea; Silvestri, Valentina; Crebelli, Riccardo; Marcon, Francesca

2015-02-01

The influence of DNA repair capacity, plasma nutrients and tobacco smoke exposure on DNA methylation was investigated in blood cells of twenty-one couples of monozygotic twins with discordant smoking habits. All study subjects had previously been characterized for mutagen sensitivity with challenge assays with ionizing radiation in peripheral blood lymphocytes. Plasma levels of folic acid, vitamin B12 and homocysteine were also available from a previous investigation. In this work DNA methylation in the promoter region of a panel of ten genes involved in cell cycle control, differentiation, apoptosis and DNA repair (p16, FHIT, RAR, CDH1, DAPK1, hTERT, RASSF1A, MGMT, BRCA1 and PALB2) was assessed in the same batches of cells isolated for previous studies, using the methylation-sensitive high-resolution melting technique. Fairly similar profiles of gene promoter methylation were observed within co-twins compared to unrelated subjects (p= 1.23 × 10(-7)), with no significant difference related to smoking habits (p = 0.23). In a regression analysis the methylation index of study subjects, used as synthetic descriptor of overall promoter methylation, displayed a significant inverse correlation with radiation-induced micronuclei (p = 0.021) and plasma folic acid level (p = 0.007) both in smokers and in non-smokers. The observed association between repair of radiation-induced DNA damage and promoter methylation suggests the involvement of the DNA repair machinery in DNA modification. Data also highlight the possible modulating effect of folate deficiency on DNA methylation and the strong influence of familiarity on the individual epigenetic profile. Copyright © 2015 Elsevier B.V. All rights reserved.

COX-2 gene expression in colon cancer tissue related to regulating factors and promoter methylation status

International Nuclear Information System (INIS)

Asting, Annika Gustafsson; Carén, Helena; Andersson, Marianne; Lönnroth, Christina; Lagerstedt, Kristina; Lundholm, Kent

2011-01-01

Increased cyclooxygenase activity promotes progression of colorectal cancer, but the mechanisms behind COX-2 induction remain elusive. This study was therefore aimed to define external cell signaling and transcription factors relating to high COX-2 expression in colon cancer tissue. Tumor and normal colon tissue were collected at primary curative operation in 48 unselected patients. COX-2 expression in tumor and normal colon tissue was quantified including microarray analyses on tumor mRNA accounting for high and low tumor COX-2 expression. Cross hybridization was performed between tumor and normal colon tissue. Methylation status of up-stream COX-2 promoter region was evaluated. Tumors with high COX-2 expression displayed large differences in gene expression compared to normal colon. Numerous genes with altered expression appeared in tumors of high COX-2 expression compared to tumors of low COX-2. COX-2 expression in normal colon was increased in patients with tumors of high COX-2 compared to normal colon from patients with tumors of low COX-2. IL1β, IL6 and iNOS transcripts were up-regulated among external cell signaling factors; nine transcription factors (ATF3, C/EBP, c-Fos, Fos-B, JDP2, JunB, c-Maf, NF-κB, TCF4) showed increased expression and 5 (AP-2, CBP, Elk-1, p53, PEA3) were decreased in tumors with high COX-2. The promoter region of COX-2 gene did not show consistent methylation in tumor or normal colon tissue. Transcription and external cell signaling factors are altered as covariates to COX-2 expression in colon cancer tissue, but DNA methylation of the COX-2 promoter region was not a significant factor behind COX-2 expression in tumor and normal colon tissue

Cloning the uteroglobin gene promoter from the relic volcano rabbit (Romerolagus diazi) reveals an ancient estrogen-response element.

Science.gov (United States)

Acosta-MontesdeOca, Adriana; Zariñán, Teresa; Macías, Héctor; Pérez-Solís, Marco A; Ulloa-Aguirre, Alfredo; Gutiérrez-Sagal, Rubén

2012-05-01

To gain further insight on the estrogen-dependent transcriptional regulation of the uteroglobin (UG) gene, we cloned the 5'-flanking region of the UG gene from the phylogenetically ancient volcano rabbit (Romerolagus diazi; Rd). The cloned region spans 812 base pairs (bp; -812/-1) and contains a noncanonical TATA box (TACA). The translation start site is 48 bp downstream from the putative transcription initiation site (AGA), and is preceded by a consensus Kozak box. Comparison of the Rd-UG gene with that previously isolated from rabbits (Oryctolagus cuniculus) showed 93% in sequence identity as well as a number of conserved cis-acting elements, including the estrogen-response element (ERE; -265/-251), which differs from the consensus by two nucleotides. In MCF-7 cells, 17β-estradiol (E(2)) induced transcription of a luciferase reporter driven by the Rd-UG promoter in a similar manner as in an equivalent rabbit UG reporter; the Rd-UG promoter was 30% more responsive to E(2) than the rabbit promoter. Mutagenesis studies on the Rd-ERE confirmed this cis-element as a target of E(2) as two luciferase mutant reporters of the Rd-promoter, one with the rabbit and the other with the consensus ERE, were more responsive to the hormone than the wild-type reporter. Gel shift and super-shift assays showed that estrogen receptor-α indeed binds to the imperfect palindromic sequence of the Rd-ERE. Copyright © 2012 Wiley Periodicals, Inc.