Detection of a Complex That Associates With the Bβ Fibrinogen G−455-A Polymorphism

Blood ◽  
1998 ◽  
Vol 92 (9) ◽  
pp. 3286-3293 ◽  
Author(s):  
Erika T. Brown ◽  
Gerald M. Fuller
Keyword(s):  
Luciferase Reporter ◽  
Molecular Evidence ◽  
Luciferase Reporter Gene ◽  
Nucleotide Substitutions ◽  
Mobility Shift ◽  
Binding Characteristics ◽  
Base Sequences ◽  
American Society ◽  
Electrophoretic Mobility Shift Assays

Abstract The promoter region of the Bβ fibrinogen gene containing the polymorphic site (G−455-A) shows an increase in fibrinogen levels for individuals containing an adenine rather than a guanine. Two methods were used to explore the possible functional role of this region. Electrophoretic mobility shift assays (EMSAs) were performed using specific DNA probes containing base sequences pertinent to the allelic site. Specific DNA binding proteins were detected and their binding characteristics were determined. Secondly, we placed DNA fragments containing different −455 nucleotide substitutions of the Bβ promoter upstream of a luciferase reporter gene and transfected them into HepG2 cells to determine their effect on transactivation. An adenine at position −455 resulted in greater luciferase activity than when a guanine was present. UV cross-linking bound protein to the DNA demonstrated a 47-kD protein binding preferentially to the site when a guanine rather than an adenine was present at −455. We hypothesize that a transactivation protein complex associates with the site, but its association is stronger when guanine is present, thereby slowing downstream Bβ gene transcription. These data provide the first molecular evidence that accounts for the increase in fibrinogen in individuals carrying this allele. © 1998 by The American Society of Hematology.

Detection of a Complex That Associates With the Bβ Fibrinogen G−455-A Polymorphism

Blood ◽  
1998 ◽  
Vol 92 (9) ◽  
pp. 3286-3293
Author(s):  
Erika T. Brown ◽  
Gerald M. Fuller
Keyword(s):  
Luciferase Reporter ◽  
Molecular Evidence ◽  
Luciferase Reporter Gene ◽  
Nucleotide Substitutions ◽  
Mobility Shift ◽  
Binding Characteristics ◽  
Base Sequences ◽  
American Society ◽  
Electrophoretic Mobility Shift Assays

The promoter region of the Bβ fibrinogen gene containing the polymorphic site (G−455-A) shows an increase in fibrinogen levels for individuals containing an adenine rather than a guanine. Two methods were used to explore the possible functional role of this region. Electrophoretic mobility shift assays (EMSAs) were performed using specific DNA probes containing base sequences pertinent to the allelic site. Specific DNA binding proteins were detected and their binding characteristics were determined. Secondly, we placed DNA fragments containing different −455 nucleotide substitutions of the Bβ promoter upstream of a luciferase reporter gene and transfected them into HepG2 cells to determine their effect on transactivation. An adenine at position −455 resulted in greater luciferase activity than when a guanine was present. UV cross-linking bound protein to the DNA demonstrated a 47-kD protein binding preferentially to the site when a guanine rather than an adenine was present at −455. We hypothesize that a transactivation protein complex associates with the site, but its association is stronger when guanine is present, thereby slowing downstream Bβ gene transcription. These data provide the first molecular evidence that accounts for the increase in fibrinogen in individuals carrying this allele.© 1998 by The American Society of Hematology.

Role of Cjun in Gγ-Globin Gene Trans-Activation.

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 1870-1870
Author(s):  
Sirisha Kodeboyina ◽  
Sima Zein ◽  
Moosueng Lee ◽  
Parimaladevi Balamurugan ◽  
Xiao Yao ◽  
...  
Keyword(s):  
Electrophoretic Mobility ◽  
Globin Gene ◽  
Fetal Hemoglobin ◽  
K562 Cells ◽  
Luciferase Reporter ◽  
Complete Analysis ◽  
Dependent Manner ◽  
Mobility Shift ◽  
Electrophoretic Mobility Shift Assays

Abstract Previous studies from our laboratory demonstrated the role of the G-CRE (Gγ-globin cAMP response element) in drug-mediated fetal hemoglobin induction. The G-CRE located at −1222 to −1229 in the promoter of Gγ-globin gene, contains binding site for trans-factors CREB1, ATF-2 and cJun. We previously demonstrated binding of phosphorylated CREB1 and ATF-2 to this element via p38 MAPK signaling triggered by sodium butyrate (NaB) and trichostatin A (TSA). Electrophoretic mobility shift assays with a probe containing the AC → TG mutation in the G-CRE (TGTGGTCA, m2) abolished trans-factor binding to the G-CRE. Furthermore, Gγ promoter activity was abolished in the PGL3 luciferase reporter vector driven by the Gγ promoter (−1500 to +36) carrying the m2 mutation. (Sangerman et al. Blood108:3590–9, 2006). Subsequent studies in our laboratory were aimed at understanding the role of trans-factor cJun, an AP-1 family member, as a regulator of Gγ-globin expression via the G-CRE site. In K562 cells treated with 2mM NaB or 0.3μM TSA for 48 hrs, cJun phosphorylation increased 2.8-fold and 6.4-fold respectively by western blot analysis. Chromatin immunoprecipitation studies showed 16-fold chromatin enrichment in the −1225 Gγ-globin region compared to IgG control studies indicative of significant cJun binding in vivo at steady state. Electrophoretic mobility shift assays using cJun monoclonal antibody demonstrated a supershifted DNA-protein complex confirming binding of cJun to the G-CRE probe. To gain evidence for a functional role of cJun, we performed enforced expression studies using the pLen-cJun vector. In a concentration dependent manner, over-expression of cJun increased luciferase activity up to 350-fold in the luciferase reporter plasmid controlled by the Gγ-promoter (−1500 to +36). As predicted from binding studies, the m2 mutation in this promoter abolished the cJunmediated trans-activation confirming that the G-CRE is required to mediate effects of cJun. We are currently investigating the ability of cJun to trans-activate the endogenous Gγ-globin gene in K562 cells. To achieve this goal, K562 stable lines were established with the expression vectors pLen-cJun and empty vector. A complete analysis of the stable lines is in progress. Future investigations to identify other components of the functional CREB1/ATF2/cJun enhanceosome complex bound to the G-CRE will be performed using affinity chromatography and mass spectrometry. This information will be used to develop strategies for fetal hemoglobin induction.

scholarly journals Transcriptional Regulation of Human 11β-Hydroxylase (hCYP11B1)

Endocrinology ◽  
2000 ◽  
Vol 141 (10) ◽  
pp. 3587-3594 ◽  
Author(s):  
Xiao-Li Wang ◽  
Mary Bassett ◽  
Yin Zhang ◽  
Su Yin ◽  
Colin Clyne ◽  
...  
Keyword(s):  
Adrenal Cortex ◽  
Electrophoretic Mobility ◽  
Binding Protein ◽  
Regulatory Elements ◽  
Expression Vectors ◽  
Luciferase Reporter ◽  
Luciferase Reporter Gene ◽  
Mobility Shift ◽  
Maximal Induction ◽  
Electrophoretic Mobility Shift Assays

Abstract Steroid 11β-hydroxylase is a mitochondrial enzyme that catalyzes the conversion of deoxycortisol to cortisol. The gene encoding human 11β-hydroxylase (hCYP11B1) is expressed in the adrenal cortex under the control of circulating levels of ACTH. The current study was undertaken to define the cis-regulatory elements and transacting factors that regulate hCYP11B1 transcription. The hCYP11B1 5′-flanking DNA was studied using transient transfection of luciferase reporter constructs in NCI-H295R human adrenocortical cells. A cAMP analogue ((Bu)2cAMP) increased expression of a construct containing −1102 bp of hCYP11B1 5′-flanking DNA (pB1–1102). An element at position −71/−64 (TGACGTGA, previously termed Ad1) resembling a consensus cAMP response element (CRE) was required for maximal induction by cAMP. The Ad1 element bound several transcriptional factors in electrophoretic mobility shift assays, including CRE-binding protein, activating transcription factor-1 (ATF-1), and ATF-2, but only the ATF-2 complex migrated similarly to a complex seen using H295R nuclear extract. In addition, Western analysis of H295R and adrenal lysates demonstrated expression of high levels of ATF-2 and ATF-1. CRE-binding protein levels varied among the strains of H295R cells tested. Transcription of CYP11B1 also appeared to be regulated by steroidogenic factor-1 (SF-1). Luciferase reporter gene activity was increased after cotransfection with expression vectors containing SF-1. An element in hCYP11B1 at positions −242/−234 (CCAAGGCTC), previously termed Ad4, was required for maximal induction by SF-1 and was found to bind SF-1 in electrophoretic mobility shift assays. The key role for SF-1 in hCYP11B1 transcription is in contrast to its lack of an effect on expression of the hCYP11B2 (aldosterone synthase) isozyme. The differential effects of SF-1 on transcription of hCYP11B1 and hCYP11B2 may be one of the mechanisms controlling differential expression of these isozymes within the zonae fasciculata and glomerulosa of the human adrenal cortex.

scholarly journals Knockdown of lncRNA X inactive specific transcript (XIST) radiosensitizes non-small cell lung cancer (NSCLC) cells through regulation of miR-16-5p/WEE1 G2 checkpoint kinase (WEE1) axis

2021 ◽  
Vol 35 ◽  
pp. 205873842096608
Author(s):  
Ran Du ◽  
Feng Jiang ◽  
Yanhua Yin ◽  
Jinfen Xu ◽  
Xia Li ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Western Blot ◽  
Small Cell ◽  
Luciferase Reporter ◽  
Small Cell Lung ◽  
Luciferase Reporter Gene ◽  
G2 Checkpoint ◽  
Qrt Pcr ◽  
Specific Transcript

Long non-coding RNA (lncRNA) X inactive specific transcript (XIST) is reported to play an oncogenic role in non-small cell lung cancer (NSCLC). However, the role of XIST in regulating the radiosensitivity of NSCLC cells remains unclear. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the expressions of XIST and miR-16-5p in NSCLC in tissues and cells, and Western blot was used to assess the expression of WEE1 G2 checkpoint kinase (WEE1). Cell counting kit-8 (CCK-8), colony formation and flow cytometry assays were used to determine cell viability and apoptosis after NSCLC cells were exposed to different doses of X-rays. The interaction between XIST and miR-16-5p was confirmed by StarBase database, qRT-PCR and dual-luciferase reporter gene assays. TargetScan database was used to predict WEE1 as a target of miR-16-5p, and their targeting relationship was further validated by Western blot, qRT-PCR and dual-luciferase reporter gene assays. XIST was highly expressed in both NSCLC tissue and cell lines, and knockdown of XIST repressed NSCLC cell viability and cell survival, and facilitated apoptosis under the irradiation. MiR-16-5p was a target of XIST, and rescue experiments demonstrated that miR-16-5p inhibitors could reverse the role of XIST knockdown on radiosensitivity in NSCLC cells. WEE1 was validated as a target gene of miR-16-5p, and WEE1 could be negatively regulated by XIST. XIST promotes the radioresistance of NSCLC cells by regulating the expressions of miR-16-5p and WEE1, which can be a novel target for NSCLC therapy.

GRAS-domain transcription factor PAT1 regulates jasmonic acid biosynthesis in grape cold stress response

2021 ◽  
Author(s):  
Zemin Wang ◽  
Darren Chern Jan Wong ◽  
Yi Wang ◽  
Guangzhao Xu ◽  
Chong Ren ◽  
...  
Keyword(s):  
Stress Response ◽  
Cold Stress ◽  
Cold Tolerance ◽  
Cold Treatment ◽  
Ectopic Expression ◽  
Bimolecular Fluorescence Complementation ◽  
Luciferase Reporter ◽  
Vitis Amurensis ◽  
Mobility Shift

Abstract Cultivated grapevine (Vitis) is a highly valued horticultural crop, and cold stress affects its growth and productivity. Wild Amur grape (Vitis amurensis) PAT1 (Phytochrome A signal transduction 1, VaPAT1) is induced by low temperature, and ectopic expression of VaPAT1 enhances cold tolerance in Arabidopsis (Arabidopsis thaliana). However, little is known about the molecular mechanism of VaPAT1 during the cold stress response in grapevine. Here, we confirmed the overexpression of VaPAT1 in transformed grape calli enhanced cold tolerance. Yeast two-hybrid and bimolecular fluorescence complementation assays highlighted an interaction between VaPAT1 with INDETERMINATE-DOMAIN 3 (VaIDD3). A role of VaIDD3 in cold tolerance was also indicated. Transcriptome analysis revealed VaPAT1 and VaIDD3 overexpression and cold treatment coordinately modulate the expression of stress-related genes including lipoxygenase 3 (LOX3), a gene encoding a key jasmonate biosynthesis enzyme. Co-expression network analysis indicated LOX3 might be a downstream target of VaPAT1. Both electrophoretic mobility shift and dual luciferase reporter assays showed the VaPAT1-IDD3 complex binds to the IDD-box (AGACAAA) in the VaLOX3 promoter to activate its expression. Overexpression of both VaPAT1 and VaIDD3 increased the transcription of VaLOX3 and JA levels in transgenic grape calli. Conversely, VaPAT1-SRDX (dominant repression) and CRISPR/Cas9-mediated mutagenesis of PAT1-ED causing the loss of the C-terminus in grape calli dramatically prohibited the accumulation of VaLOX3 and JA levels during cold treatment. Together, these findings point to a pivotal role of VaPAT1 in the cold stress response in grape by regulating JA biosynthesis.

scholarly journals Agonistic and antagonistic properties of progesterone metabolites at the human mineralocorticoid receptor

2002 ◽  
pp. 789-799 ◽  
Author(s):  
M Quinkler ◽  
B Meyer ◽  
C Bumke-Vogt ◽  
C Grossmann ◽  
U Gruber ◽  
...  
Keyword(s):  
Binding Affinity ◽  
Mineralocorticoid Receptor ◽  
Antagonistic Activity ◽  
Luciferase Reporter ◽  
Protective Mechanism ◽  
Luciferase Reporter Gene ◽  
Binding Characteristics ◽  
Rabbit Reticulocyte Lysate System ◽  
Progesterone Metabolites ◽  
Agonistic Activity

OBJECTIVE: Progesterone binds to the human mineralocorticoid receptor (hMR) with nearly the same affinity as do aldosterone and cortisol, but confers only low agonistic activity. It is still unclear how aldosterone can act as a mineralocorticoid in situations with high progesterone concentrations, e.g. pregnancy. One mechanism could be conversion of progesterone to inactive compounds in hMR target tissues. DESIGN: We analyzed the agonist and antagonist activities of 16 progesterone metabolites by their binding characteristics for hMR as well as functional studies assessing transactivation. METHODS: We studied binding affinity using hMR expressed in a T7-coupled rabbit reticulocyte lysate system. We used co-transfection of an hMR expression vector together with a luciferase reporter gene in CV-1 cells to investigate agonistic and antagonistic properties. RESULTS: Progesterone and 11beta-OH-progesterone (11beta-OH-P) showed a slightly higher binding affinity than cortisol, deoxycorticosterone and aldosterone. 20alpha-dihydro(DH)-P, 5alpha-DH-P and 17alpha-OH-P had a 3- to 10-fold lower binding potency. All other progesterone metabolites showed a weak affinity for hMR. 20alpha-DH-P exhibited the strongest agonistic potency among the metabolites tested, reaching 11.5% of aldosterone transactivation. The agonistic activity of 11beta-OH-P, 11alpha-OH-P and 17alpha-OH-P was 9, 5.1 and 4.1% respectively. At a concentration of 100 nmol/l, progesterone, 17alpha-OH-P and 20alpha-DH-P inhibit nearly 75, 40 and 35% of the transactivation by aldosterone respectively. All other progesterone metabolites tested demonstrate weaker affinity, and agonistic and antagonistic potency. CONCLUSIONS: The binding affinity for hMR and the agonistic and antagonistic activity diminish with increasing reduction of the progesterone molecule at C20, C17 and at ring A. We assume that progesterone metabolism to these compounds is a possible protective mechanism for hMR. 17alpha-OH-P is a strong hMR antagonist and could exacerbate mineralocorticoid deficiency in patients with congenital adrenal hyperplasia.

Bone Marrow Stromal Cells (BMSCs) Inhibit Retinal Ganglion Cell Apoptosis and Alleviate Inflammation Through Up-Regulation of MicroRNA-43 and Brain-Derived Neurotrophic Factor in Glaucoma

2021 ◽  
Vol 11 (12) ◽  
pp. 2478-2483
Author(s):  
Xiang Ji ◽  
Kai-Wen Zhou
Keyword(s):  
Neurotrophic Factor ◽  
Vision Loss ◽  
Luciferase Reporter ◽  
Retinal Ganglion ◽  
Luciferase Reporter Gene ◽  
Down Regulation ◽  
Related Factors ◽  
Gene Assay

Glaucoma is a leading cause of vision loss mainly due to retinal ganglion cells (RGC) loss. MicroRNAs (miRNAs) are highlighted as potential biomarkers in diseases. This study aims to investigate the role of miR-43 and BMSCs in the RGC apoptosis and glaucoma.RGCs were transfected with miR-43 inhibitors and mimics, and then co-cultured with BMSCs. RT-qPCR analysis was conducted to determine miR-43 expression, whilst Western blot, and flow cytometry were carried out to assess the role of miR-43 in apoptosis and inflammation. The interaction between miR-43 and BDNF, a neurotrophic factor, was detected by dual-luciferase reporter gene assay. Overexpression of miR-43 promoted RGC proliferation and decreased apoptosis. Furthermore, miR-43 overexpression diminished the contents of apoptosis- and inflammatory-related factors, and elevated the expression of BDNF. Down-regulation of BDNF exerted similar effect as down-regulation of miR-43, enhancing apoptosis and aggravating inflammation. Importantly, BMSC treatment reversed the in vitro inhibitory effect of si-BDNF on RGC with enhancement of miR-43 expression. Mechanically, miR-43 was indicated to target BDNF in glaucoma. Collectively, miR-43 delivered by BMSCs plays an important role in the inflammatory injury and abnormal apoptosis of RGC by regulating the expression of BDNF. These findings might help development of new treatment for glaucoma and provide a promising biomarker for diagnosis and treatment.

Distinct functional contributions of 2 GABP–NRF-2 recognition sites within the context of the human TOMM70 promoter

2006 ◽  
Vol 84 (5) ◽  
pp. 813-822 ◽  
Author(s):  
José R. Blesa ◽  
José Hernández-Yago
Keyword(s):  
Chromatin Immunoprecipitation ◽  
Binding Sites ◽  
Site Directed Mutagenesis ◽  
Outer Mitochondrial Membrane ◽  
Mobility Shift ◽  
A Subunit ◽  
Expression Evidence ◽  
Electrophoretic Mobility Shift Assays

TOMM70 is a subunit of the outer mitochondrial membrane translocase that plays a major role as a receptor of hydrophobic preproteins targeted to mitochondria. We have previously reported 2 binding sites for the transcription factor GABP–NRF-2 in the promoter region of the human TOMM70 gene that are important in activating transcription. To assess the functionality and actual role of these sites, chromatin immunoprecipitation, site-directed mutagenesis, and electrophoretic mobility shift assays were carried out. We conclude that GABP–NRF-2 binds in vivo to the TOMM70 promoter, and that the 2 GABP–NRF-2 binding sites of the promoter have different functional contributions in promoting TOMM70 expression. Evidence is provided that they work in an additive manner as single sites.

scholarly journals Xiao Yao San against Corticosterone-Induced Stress Injury via Upregulating Glucocorticoid Receptor Reaction Element Transcriptional Activity

2016 ◽  
Vol 2016 ◽  
pp. 1-14 ◽  
Author(s):  
Guoping Cao ◽  
Shenglan Gong ◽  
Fengxue Zhang ◽  
Wenjun Fu
Keyword(s):  
Hippocampal Neurons ◽  
Transcriptional Activity ◽  
Nuclear Translocation ◽  
Luciferase Reporter ◽  
Potential Candidate ◽  
Luciferase Reporter Gene ◽  
Mobility Shift ◽  
Stress Injury ◽  
Induced Stress

Previous studies have revealed that uncontrollable stress can impair the synaptic plasticity and firing property of hippocampal neurons, which influenced various hippocampal-dependent tasks including memory, cognition, behavior, and mood. In this work, we had investigated the effects and mechanisms of the Chinese herbal medicine Xiao Yao San (XYS) against corticosterone-induced stress injury in primary hippocampal neurons (PHN) cells. We found that XYS and RU38486 could increase cell viabilities and decrease cell apoptosis by MTT, immunofluorescence, and flow cytometry assays. In addition, we observed that XYS notably inhibited the nuclear translocation of GR and upregulated the mRNA and protein expressions levels of Caveolin-1, GR, BDNF, TrkB, and FKBP4. However, XYS downregulated the FKBP51 expressions. Furthermore, the results of the electrophoretic mobility shift assay (EMSA) and double luciferase reporter gene detection indicated that FKBP4 promotes the transcriptional activity of GR reaction element (GRE) by binding with GR, and FKBP51 processed the opposite action. Thein vivoexperiment also proved the functions of XYS. These results suggested that XYS showed an efficient neuroprotection against corticosterone-induced stress injury in PHN cells by upregulating GRE transcriptional activity, which should be developed as a potential candidate for treating stress injury in the future.

microRNA-422a Inhibits DCC Expression in a Manner Dependent on SNP rs12607853

2020 ◽  
Vol 160 (2) ◽  
pp. 63-71
Author(s):  
Yunxiao Li ◽  
Xugang Shi ◽  
Xintong Cai ◽  
Yongsheng Zhu ◽  
Yuanyuan Chen ◽  
...  
Keyword(s):  
Gene Expression ◽  
Opioid Addiction ◽  
Heroin Addiction ◽  
Luciferase Reporter ◽  
Luciferase Reporter Gene ◽  
Protein Levels ◽  
Gene Assay ◽  
New Biomarkers ◽  
And Function

DCC netrin 1 receptor (DCC) affects the structure and function of the dopamine circuitry, which in turn affects the susceptibility to developing addiction. In a previous study, we found that single nucleotide polymorphism (SNP) rs12607853 in the 3′ untranslated region (3′-UTR) of DCC was significantly associated with heroin addiction. In the current study, we first used bioinformatics prediction to identify the DCC rs12607853 C allele as a potential hsa-miR-422a and hsa-miR-378c target site. We then used vector construction and dual-luciferase reporter assays to investigate the targeting relationship of DCC rs12607853 with hsa-miR-422a and hsa-miR-378c. The dual-luciferase reporter gene assay confirmed that the C allele of rs12607853 in combination with hsa-miR-422a led to repressed dual-luciferase gene expression. Moreover, gene expression assays disclosed that hsa-miR-422a inhibited DCC expression at both the mRNA and protein levels. We also found that morphine inhibited the expression of hsa-miR-422a but increased the expression of DCC mRNA, and this change in the expression of hsa-miR-422a could not be reversed by naloxone, which suggested that the role of DCC in opioid addiction might be regulated by hsa-miR-422a. In summary, this study improves our understanding of the role of hsa-miR-422a and identifies the genetic basis of rs12607853, which might contribute to the discovery of new biomarkers or therapeutic targets for opioid addiction.

Sign in / Sign up

Export Citation Format

Share Document