scholarly journals PgMYB2, a MeJA-Responsive Transcription Factor, Positively Regulates the Dammarenediol Synthase Gene Expression in Panax Ginseng

2019 ◽  
Vol 20 (9) ◽  
pp. 2219 ◽  
Author(s):  
Tuo Liu ◽  
Tiao Luo ◽  
Xiangqian Guo ◽  
Xian Zou ◽  
Donghua Zhou ◽  
...  
Keyword(s):  
Gene Expression ◽  
Transcription Factor ◽  
Panax Ginseng ◽  
Growth Regulation ◽  
Ginseng Root ◽  
Myb Transcription Factor ◽  
Mobility Shift ◽  
Binding Interaction ◽  
Mobility Shift Assay ◽  
Dammarenediol Synthase

The MYB transcription factor family members have been reported to play different roles in plant growth regulation, defense response, and secondary metabolism. However, MYB gene expression has not been reported in Panax ginseng. In this study, we isolated a gene from ginseng adventitious root, PgMYB2, which encodes an R2R3-MYB protein. Subcellular localization revealed that PgMYB2 protein was exclusively detected in the nucleus of Allium cepa epidermis. The highest expression level of PgMYB2 was found in ginseng root and it was significantly induced by plant hormones methyl jasmonate (MeJA). Furthermore, the binding interaction between PgMYB2 protein and the promoter of dammarenediol synthase (DDS) was found in the yeast strain Y1H Gold. Moreover, the electrophoretic mobility shift assay (EMSA) identified the binding site of the interaction and the results of transiently overexpressing PgMYB2 in plants also illustrated that it may positively regulate the expression of PgDDS. Based on the key role of PgDDS gene in ginsenoside synthesis, it is reasonable to believe that this report will be helpful for the future studies on the MYB family in P. ginseng and ultimately improving the ginsenoside production through genetic and metabolic engineering.

scholarly journals The R2R3-type MYB transcription factor MdMYB90-like is responsible for the enhanced skin color of an apple bud sport mutant

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Chao Sun ◽  
Chunming Wang ◽  
Wang Zhang ◽  
Shuai Liu ◽  
Weiyao Wang ◽  
...  
Keyword(s):  
Transcription Factor ◽  
Skin Color ◽  
Anthocyanin Biosynthesis ◽  
Regulatory Gene ◽  
Gene Promoter ◽  
Luciferase Assay ◽  
Myb Transcription Factor ◽  
Anthocyanin Content ◽  
Mobility Shift ◽  
Mobility Shift Assay

AbstractThe anthocyanin content in apple skin determines its red coloration, as seen in a Fuji apple mutant. Comparative RNA-seq analysis was performed to determine differentially expressed genes at different fruit development stages between the wild-type and the skin color mutant. A novel R2R3-MYB transcription factor, MdMYB90-like, was uncovered as the key regulatory gene for enhanced coloration in the mutant. The expression of MdMYB90-like was 21.3 times higher in the mutant. MdMYB90-like regulates anthocyanin biosynthesis directly through the activation of anthocyanin biosynthesis genes and indirectly through the activation of other transcription factors that activate anthocyanin biosynthesis. MdMYB90-like bound to the promoters of both structural genes (MdCHS and MdUFGT) and other transcription factor genes (MdMYB1 and MdbHLH3) in the yeast one-hybrid system, electrophoretic mobility shift assay, and dual-luciferase assay. Transgenic analysis showed that MdMYB90-like was localized in the nucleus, and its overexpression induced the expression of other anthocyanin-related genes, including MdCHS, MdCHI, MdANS, MdUFGT, MdbHLH3, and MdMYB1. The mutant had reduced levels of DNA methylation in two regions (−1183 to −988 and −2018 to −1778) of the MdMYB90-like gene promoter, which might explain the enhanced expression of the gene and the increased anthocyanin content in the mutant apple skin.

Mechanism of RSV-induced IL-8 gene expression in A549 cells before viral replication

1996 ◽  
Vol 271 (6) ◽  
pp. L963-L971 ◽  
Author(s):  
M. A. Fiedler ◽  
K. Wernke-Dollries ◽  
J. M. Stark
Keyword(s):  
Gene Expression ◽  
Transcription Factor ◽  
Viral Replication ◽  
Transcriptional Activation ◽  
Mutational Analysis ◽  
A549 Cells ◽  
Nf Kappa B ◽  
Mobility Shift ◽  
Syncytial Virus ◽  
Time Point

Previous studies demonstrated that respiratory syncytial virus (RSV) infection of A549 cells induced interleukin (IL)-8 gene expression and protein release from the cells as early as 2 h after treatment [M. A. Fiedler, K. Wernke-Dollries, and J. M. Stark. Am. J. Physiol. 269 (Lung Cell. Mol. Physiol. 13): L865-L872, 1995; J. G. Mastronarde, M. M. Monick, and G. W. Hunninghake. Am. J. Respir. Cell Mol. Biol. 13: 237-244, 1995]. Furthermore, the effects of RSV at the 2-h time point were not dependent on viral replication. The studies reported here were designed to test the hypothesis that active and inactive RSV induce IL-8 gene expression in A549 cells at the 2-h time point by a mechanism dependent on the activation of the nuclear transcription factor NF-kappa B Northern blot analysis indicated that IL-8 gene expression occurred independent of protein synthesis 2 h after A549 cells were treated with RSV. Analysis of nuclear extracts from RSV-treated A549 cells by electrophoretic mobility shift assays demonstrated that NF-kappa B was activated as early as 15 min after RSV was added to the cells and remained activated for at least 90 min. In contrast, baseline levels of NF-IL-6 and activator protein-1 (AP-1) did not change over this period of time. Deoxyribonuclease footprint analysis of a portion of the 5'-flanking region of the IL-8 gene demonstrated two potential regions for transcription factor binding, which corresponded to the potential AP-1 binding site, and potential NF-IL-6 and NF-kappa B binding sites. Mutational analysis of the 200-bp 5'-untranslated region of the IL-8 gene demonstrated that activation of NF-kappa B and NF-IL-6 were required for RSV-induced transcriptional activation of the IL-8 gene.

Identification of a killer cell-specific regulatory element of the mouse perforin gene: an Ets-binding site-homologous motif that interacts with Ets-related proteins

1993 ◽  
Vol 13 (11) ◽  
pp. 6690-6701
Author(s):  
H Koizumi ◽  
M F Horta ◽  
B S Youn ◽  
K C Fu ◽  
B S Kwon ◽  
...  
Keyword(s):  
Gene Expression ◽  
Dna Binding ◽  
Binding Site ◽  
Protein Interactions ◽  
Regulatory Element ◽  
Killer Cell ◽  
Mobility Shift ◽  
Specific Expression ◽  
Native Molecular Mass ◽  
Mobility Shift Assay

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

NG-monomethyl-l-arginine inhibits erythropoietin gene expression by stimulating GATA-2

Blood ◽  
2000 ◽  
Vol 96 (5) ◽  
pp. 1716-1722 ◽  
Author(s):  
Takahisa Tarumoto ◽  
Shigehiko Imagawa ◽  
Ken Ohmine ◽  
Tadashi Nagai ◽  
Masato Higuchi ◽  
...  
Keyword(s):  
Gene Expression ◽  
Transcription Factor ◽  
Messenger Rna ◽  
Promoter Activity ◽  
Binding Activity ◽  
Guanosine Monophosphate ◽  
Mobility Shift ◽  
Enhancer Activity ◽  
Gata Transcription Factor ◽  
Hep3b Cells

Abstract NG-monomethyl-l-arginine (L-NMMA) has been reported to be elevated in uremic patients. Based on the hypothesis that the pathogenesis of the anemia of renal disease might be due to the perturbation of transcription factors of the erythropoietin (Epo) gene by L-NMMA, the present study was designed to investigate the effect of L-NMMA on Epo gene expression through the GATA transcription factor. L-NMMA caused decreased levels of NO, cyclic guanosine monophosphate (cGMP), and Epo protein in Hep3B cells. L-NAME (analogue of L-NMMA) also inhibited Epo production in anemic mice. Transfection of the Epo promoter-luciferase gene into Hep3B cells revealed that L-NMMA inhibited the Epo promoter activity. However, L-NMMA did not inhibit the Epo promoter activity when mutated Epo promoter (GATA to TATA) was transfected, and L-NMMA did not affect the enhancer activity. Electrophoretic mobility shift assays demonstrated the stimulation of GATA binding activity by L-NMMA. However, L-NMMA had no effect on the binding activity of hepatic nuclear factor-4, COUP-TF1, hypoxia-inducing factor-1, or NF-κB. Furthermore, cGMP inhibited the L-NMMA–induced GATA binding activity. L-NMMA also increased GATA-2 messenger RNA expression. These results demonstrate that L-NMMA suppresses Epo gene expression by up-regulation of the GATA transcription factor and support the hypothesis that L-NMMA is one of the candidate substances that underlie the pathogenesis of renal anemia.

scholarly journals The grapevine R2R3-type MYB transcription factor VdMYB1 positively regulates defense responses by activating the stilbene synthase gene 2 (VdSTS2)

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Yihe Yu ◽  
Dalong Guo ◽  
Guirong Li ◽  
Yingjun Yang ◽  
Guohai Zhang ◽  
...  
Keyword(s):  
Gene Expression ◽  
Transcription Factor ◽  
Transcriptional Activation ◽  
Molecular Mechanisms ◽  
Plant Protection ◽  
Defense Responses ◽  
Stilbene Synthase ◽  
Myb Transcription Factor ◽  
Wide Range ◽  
Grapevine Leaves

Abstract Background Resveratrol is a naturally occurring plant stilbene that exhibits a wide range of valuable biological and pharmacological properties. Although the beneficial effects of trans-resveratrol to human health and plant protection against fungal pathogens and abiotic stresses are well-established, yet little is known about the molecular mechanisms regulating stilbene biosynthesis in plant defense progress. Results Here, we cloned and identified the Chinese wild grape (Vitis davidii) R2R3-MYB transcription factor VdMYB1, which activates defense responses against invading pathogen. VdMYB1 transcripts were significantly upregulated after inoculation with the grapevine powdery mildew fungus Erysiphe necator (Schw.) Burr. Transient expression analysis using onion epidermal cells and Arabidopsis thaliana protoplasts showed that VdMYB1 was localized in the nucleus. Yeast one-hybrid assays revealed that VdMYB1 acts as a transcriptional activator. Grapevine leaves transiently overexpressing VdMYB1 showed a lower number of fungal conidiophores compared with wild-type leaves. Overexpression of VdMYB1 in grapevine leaves did not alter the expression of genes in salicylic acid- and jasmonate-dependent pathways, but affected the expression of stilbene synthase (STS) genes, key regulators of flavonoid metabolism. Results of electrophoretic mobility shift assays and in vivo transcriptional activation assays showed that VdMYB1 binds to the MYB binding site (MYBBS) in the STS2 gene promoter, thus activating STS2 transcription. In heterologous expression assays using tobacco leaves, VdMYB1 activated STS2 gene expression and increased the accumulation of resveratrol. Conclusions Our study showed that VdMYB1 activates STS2 gene expression to positively regulate defense responses, and increases the content of resveratrol in leaves.

scholarly journals Transcriptional activation of the H-ferritin gene in differentiated Caco-2 cells parallels a change in the activity of the nuclear factor Bbf

1995 ◽  
Vol 311 (3) ◽  
pp. 769-773 ◽  
Author(s):  
M A Bevilacqua ◽  
M C Faniello ◽  
P D′Agostino ◽  
B Quaresima ◽  
M T Tiano ◽  
...  
Keyword(s):  
Transcription Factor ◽  
Transcriptional Activation ◽  
Mobility Shift ◽  
Differentiated Cells ◽  
Binding Factor ◽  
H Gene ◽  
Ferritin Gene ◽  
Mobility Shift Assay ◽  
Promoter Interaction

In this paper, we examine the mechanisms that regulate the expression of the heavy (H) ferritin subunit in the colon carcinoma Caco-2 cell line allowed to differentiate spontaneously in vitro. The differentiation process of these cells in continuous culture is accompanied by an accumulation of the mRNA coding for the apoferritin H chain. The analysis of Caco-2 subclones stably transfected with an H-chain promoter-chloramphenicol acetyltransferase (CAT) construct revealed that the mRNA increase is paralleled by an enhanced transcription of the H gene, driven by the -100 to +4 region of the H promoter. The H gene transcriptional activation seems to be a specific feature of differentiated Caco-2 cells, since the activity of other promoters did not change upon differentiation. The -100 to +4 region of the H promoter binds a transcription factor called Bbf (B-box binding factor); electrophoretic-mobility-shift-assay analyses showed that the retarded complex due to Bbf-H promoter interaction is significantly increased in the differentiated cells. We propose that the activation of H-ferritin gene expression may be associated with the establishment of a differentiated phenotype in Caco-2 cells, and that the H-ferritin gene transcriptional up-regulation is accompanied by a modification in the activity of the transcription factor Bbf.

Inhibition of transcription factor assembly and structural stability on mitoxantrone binding with DNA

2010 ◽  
Vol 30 (5) ◽  
pp. 331-340 ◽  
Author(s):  
Shahper N. Khan ◽  
Mohd Danishuddin ◽  
Asad U. Khan
Keyword(s):  
Transcription Factor ◽  
Binding Mode ◽  
Cd Spectroscopy ◽  
Sequence Specificity ◽  
Mobility Shift ◽  
Dna Complexes ◽  
Naked Dna ◽  
Plasmid Nicking Assay ◽  
Modelling Studies ◽  
Mobility Shift Assay

MTX (mitoxantrone) is perhaps the most promising drug used in the treatment of various malignancies. Comprehensive literature on the therapeutics has indicated it to be the least toxic in its class, although its mechanism of action is still not well defined. In the present study, we have evaluated the associated binding interactions of MTX with naked DNA. The mechanism of MTX binding with DNA was elucidated by steady-state fluorescence and a static-type quenching mechanism is suggested for this interaction. Thermodynamic parameters from van 't Hoff plots showed that the interaction of these drugs with DNA is an entropically driven phenomenon. The binding mode was expounded by attenuance measurements and competitive binding of a known intercalator. Sequence specificity of these drug–DNA complexes was analysed by FTIR (Fourier-transform infrared) spectroscopy and molecular modelling studies. CD spectroscopy and the plasmid nicking assay showed that the binding of this drug with DNA results in structural and conformational perturbations. EMSA (electrophoretic mobility-shift assay) results showed that these drug–DNA complexes prevent the binding of octamer TF (transcription factor) to DNA. In summary, the study implicates MTX-induced conformational instability and transcription inhibition on DNA binding.

scholarly journals Factors involved in specific transcription by mammalian RNA polymerase II: purification and analysis of transcription factor IIA and identification of transcription factor IIJ.

1992 ◽  
Vol 12 (1) ◽  
pp. 413-421 ◽  
Author(s):  
P Cortes ◽  
O Flores ◽  
D Reinberg
Keyword(s):  
Transcription Factor ◽  
Rna Polymerase Ii ◽  
Stable Complex ◽  
Mobility Shift ◽  
Yeast Saccharomyces Cerevisiae ◽  
Gel Mobility Shift Assay ◽  
Two Factors ◽  
Mobility Shift Assay ◽  
Gel Mobility Shift ◽  
Tfiid Complex

The previously described transcription factor IIA (TFIIA) protein fraction was separated into two factors that affect transcription, TFIIA and TFIIJ. TFIIA was found to have a stimulatory effect, and TFIIJ was found to be required for transcription. The requirement of TFIIJ was observed when bacterially produced purified human or yeast (Saccharomyces cerevisiae) TATA-binding protein (TBP) was used in lieu of the endogenous HeLa cell TFIID complex, suggesting that TFIIJ may be part of the TFIID complex. The stimulatory activity of TFIIA was found also to be dependent on the source of the TBP. Transcription reactions reconstituted with TFIID were stimulated by TFIIA; however, when human or yeast TBP was used instead of TFIID, TFIIA had no effect. TFIIA was found to interact with the TBP and was extensively purified by the use of affinity chromatography on columns containing immobilized recombinant yeast TBP. TFIIA is a heterotrimer composed of polypeptides of 34, 19, and 14 kDa. These three polypeptides were required to isolate, by using the gel mobility shift assay, a stable complex between TBP and the TATA box sequence.

scholarly journals Pituitary homeobox 1 (Pitx1) stimulates rat LHβ gene expression via two functional DNA-regulatory regions

2005 ◽  
Vol 35 (1) ◽  
pp. 145-158 ◽  
Author(s):  
Qiaorong Jiang ◽  
Kyeong-Hoon Jeong ◽  
Cheryl D Horton ◽  
Lisa M Halvorson
Keyword(s):  
Gene Expression ◽  
Molecular Mechanisms ◽  
Gene Promoter ◽  
Orphan Nuclear Receptor ◽  
Mobility Shift ◽  
Regulatory Regions ◽  
Steroidogenic Factor 1 ◽  
Reproductive Axis ◽  
Functional Dna ◽  
Mobility Shift Assay

Luteinizing hormone (LH) plays a central role in the reproductive axis, stimulating both gonadal steroid biosynthesis and the development of mature gametes. Over the past decade, significant progress has been made in characterizing the transcription factors and associated DNA-regulatory sites which mediate expression of the LH β-subunit gene (LHβ). One of these factors, pituitary homeobox 1 (Pitx1), has been shown to stimulate LHβ gene promoter activity, both alone and in synergy with the orphan nuclear receptor, steroidogenic factor-1 (SF-1), and the early growth response gene 1 (Egr-1). Prior reports have attributed the Pitx1 response to a cis-element located at position -101 in the rat LHβ gene promoter. While investigating the role of Pitx1 in regulating rat LHβ gene expression, we observed a small, but significant, residual Pitx1 response despite mutation or deletion of this site. In the studies presented here, we identify the presence of a second functional Pitx1 region spanning positions −73 to −52 in the rat LHβ gene promoter. Based on electrophoretic mobility shift assay, Pitx1 binds to both the initially described 5′Pitx1 site as well as this putative 3′Pitx1 region. In transient transfection analysis, mutation of the LHβ-3′Pitx1 site significantly blunted Pitx1 responsiveness, with elimination of the Pitx1 response in a construct containing mutations in both Pitx1 cis-elements. We also analyzed the importance of each of these Pitx1 sites for providing functional synergy with SF-1 and with Egr-1. We observed a markedly decreased synergistic response with mutation of the 5′Pitx1 site with further loss following mutation of the 3′Pitx1 site. In contrast, functional interaction between Pitx1 and Egr-1 persisted with mutation of both Pitx1 regions. We conclude that Pitx1 stimulates the rat LHβ gene promoter via two Pitx1 DNA-regulatory regions. These results further our understanding of the molecular mechanisms that regulate expression of this critical reproductive gene promoter.

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