scholarly journals Isolation of the LEMMI9 Gene and Promoter Analysis During a Compatible Plant-Nematode Interaction

1999 ◽  
Vol 12 (5) ◽  
pp. 440-449 ◽  
Author(s):  
Carolina Escobar ◽  
Jan De Meutter ◽  
Fabio A. Aristizábal ◽  
Soledad Sanz-Alférez ◽  
Francisca F. del Campo ◽  
...  
Keyword(s):  
Transcriptional Activation ◽  
Protein Complexes ◽  
Transgenic Potato ◽  
Giant Cells ◽  
Proximal Region ◽  
Regulatory Sequences ◽  
Promoter Recognition ◽  
Plant Nematode ◽  
Plant Genes ◽  
Protein Binding Sequence

Plant-endoparasitic root-knot nematodes feed on specialized giant cells that they induce in the vascular cylinder of susceptible plants. Although it has been established that a number of plant genes change their expression pattern during giant cell differentiation, virtually no data are available about the mechanisms involved in that change. One possibility is differential promoter recognition by the transcription factor(s) responsible for the expression of specific genes. We have isolated and characterized a genomic clone from tomato containing the promoter region of LEMMI9, one of the few plant genes that have been reported to be highly expressed in galls (predominantly in giant cells). The analysis of transgenic potato plants carrying a LEMMI9 promoter-β glucuronidase (GUS) fusion has demonstrated that the tomato promoter was activated in Meloidogyne incognita-induced galls in a heterologous system. We have located putative regulatory sequences in the promoter and have found that nuclear proteins from the galls formed specific DNA-protein complexes with the proximal region of the LEMMI9 promoter. The nuclear protein-binding sequence mapped to a region of 111 bp immediately upstream from the TATA box. This region contains a 12-bp repeat possibly involved in the formation of DNA-protein complexes, which might be related to the LEMMI9 transcriptional activation in the giant cells.

scholarly journals Role of Nrf2 in the regulation of the Mrp2 (ABCC2) gene

2006 ◽  
Vol 395 (3) ◽  
pp. 599-609 ◽  
Author(s):  
Valeska Vollrath ◽  
Ana M. Wielandt ◽  
Mirentxu Iruretagoyena ◽  
Jose Chianale
Keyword(s):  
Gene Expression ◽  
Transcriptional Activation ◽  
Protein Complexes ◽  
Antioxidant Response ◽  
Proximal Region ◽  
Common Mechanism ◽  
Related Factor ◽  
Key Enzyme ◽  
Chloramphenicol Acetyltransferase Gene ◽  
Nrf2 Protein

The Nrf2 (nuclear factor-erythroid 2 p45-related factor 2) transcription factor regulates gene expression of the GCLC (glutamate–cysteine ligase catalytic subunit), which is a key enzyme in glutathione synthesis, and GSTs (glutathione S-transferases) via the ARE (antioxidant-response element). The Mrp2 (multidrug-resistance protein 2) pump mediates the excretion of GSH and GSSG excretion as well as endo- and xeno-biotics that are conjugated with GSH, glucuronate or sulphate. Considering that Mrp2 acts synergistically with these enzymes, we hypothesized that the regulation of Mrp2 gene expression is also dependent on Nrf2. Using BHA (butylated hydroxyanisole), which is a classical activator of the ARE–Nrf2 pathway, we observed an increase in the transcriptional activity of Mrp2, GCLC and Gsta1/Gsta2 genes in the mouse liver. A similar pattern of co-induction of Mrp2 and GCLC genes was also observed in mouse (Hepa 1-6) and human (HepG2) hepatoma cells treated with BHA, β-NF (β-naphthoflavone), 2,4,5-T (trichlorophenoxyacetic acid) or 2AAF (2-acetylaminofluorene), suggesting that these genes share common mechanism(s) of transcriptional activation in response to exposure to xenobiotics. To define the mechanism of Mrp2 gene induction, the 5′-flanking region of the mouse Mrp2 gene (2.0 kb) was isolated, and two ARE-like sequences were found: ARE-2 (−1391 to −1381) and ARE-1 (−95 to −85). Deletion analyses demonstrated that the proximal region (−185 to +99) contains the elements for the basal expression and xenobiotic-mediated induction of the Mrp2 gene. Gel-shift and supershift assays indicated that Nrf2–protein complexes bind ARE sequences of the Mrp2 promoter, preferentially to the ARE-1 sequence. Overexpression of Nrf2 increased ARE-1-mediated CAT (chloramphenicol acetyltransferase) gene activity, while overexpression of mutant Nrf2 protein repressed the activity. Thus Nrf2 appears to regulate Mrp2 gene expression via an ARE element located at the proximal region of its promoter in response to exposure to xenobiotics.

scholarly journals Structure of yellow lupine genes coding for mitotic cyclins.

1999 ◽  
Vol 46 (3) ◽  
pp. 759-769
Author(s):  
J Jeleńska ◽  
Z Zaborowska ◽  
A B Legocki
Keyword(s):  
Cell Cycle Progression ◽  
Cyclin B1 ◽  
Regulatory Elements ◽  
Regulatory Sequences ◽  
Cycle Progression ◽  
Coding Regions ◽  
Mitotic Cyclin ◽  
Plant Genes ◽  
Yellow Lupine ◽  
First Time

Cell cycle progression in eukaryotes is controlled by complexes of p34 protein kinases and cyclins. For the first time in plants, we have established the sequence of four yellow lupine mitotic cyclin B1 genes. Their coding regions and expression pattern were also characterised recently. Structure of all the four lupine genes is similar: they consist of nine exons and eight introns, analogously located, except Luplu;CycB1;3 lacking 7th intron. Analysis of 5'-regulatory sequences of two of them showed that both comprise M-specific activators (MSA), common to plant genes induced in late G2 and early M. Putative repressor binding sites CDE/CHR found in animal G2-specific promoters can also be detected in lupine genes. Controlling region of Luplu;CycB1;4 gene that is highly activated by IAA, contains up to 7 auxin response elements, while insensible to IAA Luplu;CycB1;4 gene have no such motifs. Further studies should be undertaken to determine precisely the functions of putative regulatory elements in the expression of lupine mitotic cyclins.

scholarly journals A simple promoter containing two Sp1 sites controls the expression of sterol-regulatory-element-binding protein 1a (SREBP-1a)

2005 ◽  
Vol 386 (1) ◽  
pp. 161-168 ◽  
Author(s):  
Chengkang ZHANG ◽  
Dong-Ju SHIN ◽  
Timothy F. OSBORNE
Keyword(s):  
Transcriptional Activation ◽  
Binding Protein ◽  
Regulatory Element ◽  
Animal Experiments ◽  
Proximal Region ◽  
Mrna Levels ◽  
Relative Level ◽  
Transcriptional Activation Domain ◽  
Element Binding Protein ◽  
Sterol Regulatory Element

The mammalian gene for SREBP-1 (sterol-regulatory-element-binding protein 1) contains two promoters that control the production of two proteins, SREBP-1a and -1c, and each contains a unique N-terminal transcriptional activation domain, but they are otherwise identical. The relative level of each mRNA varies from tissue to tissue and they respond differently to regulatory stimuli. SREBP-1c is more abundantly expressed in liver, where its level is also regulated by insulin and liver X receptor activators, and it is also autoregulated by SREBPs. In contrast, SREBP-1a mRNA levels are relatively low and constant in different tissues and few studies have specifically analysed its pattern of expression and regulation. In the present study, we show that the promoter for SREBP-1a is contained in a very small promoter-proximal region containing two Sp1 sites. The small and relatively simple structure for its promoter provides an explanation for the low level of SREBP-1a expression. Additionally, since Sp1 has been implicated in the modest regulation of several genes by insulin, its involvement in the expression of the SREBP-1a promoter provides an explanation for the modest insulin regulation observed in animal experiments.

scholarly journals HMGA1 Modulates Gene Transcription Sustaining a Tumor Signalling Pathway Acting on the Epigenetic Status of Triple-Negative Breast Cancer Cells

Cancers ◽  
2019 ◽  
Vol 11 (8) ◽  
pp. 1105 ◽  
Author(s):  
Penzo ◽  
Arnoldo ◽  
Pegoraro ◽  
Petrosino ◽  
Ros ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Cancer Cells ◽  
Triple Negative Breast Cancer ◽  
Transcriptional Activation ◽  
Triple Negative ◽  
Critical Factor ◽  
Regulatory Sequences ◽  
Breast Cancers ◽  
Creb Binding Protein ◽  
Mesenchymal Transition

Chromatin accessibility plays a critical factor in regulating gene expression in cancer cells. Several factors, including the High Mobility Group A (HMGA) family members, are known to participate directly in chromatin relaxation and transcriptional activation. The HMGA1 oncogene encodes an architectural chromatin transcription factor that alters DNA structure and interacts with transcription factors favouring their landing onto transcription regulatory sequences. Here, we provide evidence of an additional mechanism exploited by HMGA1 to modulate transcription. We demonstrate that, in a triple-negative breast cancer cellular model, HMGA1 sustains the action of epigenetic modifiers and in particular it positively influences both histone H3S10 phosphorylation by ribosomal protein S6 kinase alpha-3 (RSK2) and histone H2BK5 acetylation by CREB-binding protein (CBP). HMGA1, RSK2, and CBP control the expression of a set of genes involved in tumor progression and epithelial to mesenchymal transition. These results suggest that HMGA1 has an effect on the epigenetic status of cancer cells and that it could be exploited as a responsiveness predictor for epigenetic therapies in triple-negative breast cancers.

scholarly journals Cks1 Activates Transcription by Binding to the Ubiquitylated Proteasome

2010 ◽  
Vol 30 (15) ◽  
pp. 3894-3901 ◽  
Author(s):  
Roman Holic ◽  
Alexander Kukalev ◽  
Sophie Lane ◽  
Edward J. Andress ◽  
Ivy Lau ◽  
...  
Keyword(s):  
Gene Expression ◽  
Saccharomyces Cerevisiae ◽  
Transcriptional Activation ◽  
Protein Complexes ◽  
Cyclin Dependent Kinase ◽  
Transcription Activator ◽  
Large Protein ◽  
Ubiquitin Binding ◽  
Ubiquitin Binding Domain ◽  
Proteasome Subunits

ABSTRACT Cyclin-dependent kinase-associated protein 1 (Cks1) is involved in the control of the transcription of a subset of genes in addition to its role in controlling the cell cycle in the budding yeast Saccharomyces cerevisiae. By directly ligating Cks1 onto a GAL1 promoter-driven reporter, we demonstrated that Cks1 acts as a transcription activator. Using this method, we dissected the downstream events from Cks1 recruitment at the promoter. We showed that subsequent to promoter binding, Cdc28 binding is required to modulate the level of gene expression. The ubiquitin-binding domain of Cks1 is essential for implementing downstream transcription events, which appears to recruit the proteasome via ubiquitylated proteasome subunits. We propose that the selective ability of Cks1 to bind ubiquitin allows this small molecule the flexibility to bind large protein complexes with specificity and that this may represent a novel mechanism of regulating transcriptional activation.

scholarly journals Transcriptional activation of the chicken lysozyme gene by NF-κ Bp65 (RelA) and c-Rel, but not by NF-κ Bp50

1996 ◽  
Vol 313 (1) ◽  
pp. 39-44 ◽  
Author(s):  
Loc VAN PHI
Keyword(s):  
Transcription Factors ◽  
Transcriptional Activation ◽  
Nuclear Factor Kappa B ◽  
Protein Complexes ◽  
Terminal Differentiation ◽  
Binding Activity ◽  
Nuclear Factor ◽  
Lysozyme Gene ◽  
Chloramphenicol Acetyltransferase Gene ◽  
Chicken Lysozyme

The lysozyme gene is expressed at a low level in myeloblasts and is progressively activated to constitutively high expression in mature macrophages. The binding activity of the newly defined NF-ĸB/Rel family of transcription factors increases during the terminal differentiation of macrophages. In this study, I show that NF-ĸB/Rel-like proteins bind to the nuclear factor kappa B (ĸB)-like sequence of the lysozyme promoter. These binding activities were induced by treatment of HD11 cells with lipopolysaccharide. Immunomobility shift assays show that c-Rel is possibly a factor in the complexes that bind to the ĸB-like sequence lysĸB. Binding activity to one of the protein complexes seems to be regulated by phosphorylation. In fact, overexpression of p65 and c-Rel stimulates expression of the chloramphenicol acetyltransferase gene controlled by the lysozyme promoter. Furthermore, co-transfection experiments reveal that the ĸB-like sequence within the lysozyme promoter mediates the transactivation by p65 and c-Rel. These results indicate that the p65 and c-Rel could be components of the protein complexes that bind to the ĸB-like sequence and this binding could contribute to the progressively activated expression of the lysozyme gene during the terminal differentiation of macrophages.

scholarly journals An Af9 cis-element directly targets Dot1a to mediate transcriptional repression of the αENaC gene

2013 ◽  
Vol 304 (4) ◽  
pp. F367-F375 ◽  
Author(s):  
Wenzheng Zhang ◽  
Zhiyuan Yu ◽  
Hongyu Wu ◽  
Lihe Chen ◽  
Qun Kong ◽  
...  
Keyword(s):  
Transcriptional Activation ◽  
Transcriptional Repression ◽  
Protein Complexes ◽  
Collecting Duct ◽  
Binding Activity ◽  
Mrna Levels ◽  
Cis Element ◽  
Connecting Tubule ◽  
The Impact

The epithelial Na+ channel subunit-α ( αENaC) of the distal nephron is essential for salt balance. We previously demonstrated that the histone methyltransferase Dot1a and its protein partner Af9 basally repress αENaC transcription in mouse inner medullary collecting duct type 3 (mIMCD3) cells and link aldosterone-elicited chromatin modifications to αENaC transcriptional activation. Af9 DNA-binding activity has never been demonstrated, and whether and where Af9 binds to the αENaC promoter to target Dot1a are unknown. The present study sought to identify functional Af9 cis-element(s) in the −57/+439 “R3” subregion of αENaC, the principal site for Dot1a-Af9 interaction, in mIMCD3 cells. We also exploited connecting tubule/collecting duct-specific Dot1l-deficient mice ( Dot1l AC) to determine the impact of Dot1l inactivation on renal αENaC expression in vivo. mIMCD3 cell lines expressing αENaC promoter-reporter constructs harboring deletion of +74/+107 demonstrated greatly reduced association of Af9 and Dot1a by ChIP/qPCR. Aldosterone treatment resulted in further decrements in Af9 and Dot1a association with the αENaC promoter. Gel shift and antibody competition assays using wild-type and mutant oligomers revealed Af9-containing +78/+92 αENaC DNA-protein complexes in nuclear extracts of mIMCD3 cells. Mutation of the +78/+92 element resulted in higher basal αENaC promoter activity and impaired Dot1a-mediated inhibition in trans-repression assays. In agreement, mice with connecting tubule/collecting duct-specific knockout of Dot1l exhibited greater αENaC mRNA levels in kidney compared with control. Thus, we conclude that +78/+92 of αENaC represents the primary Af9 binding site involved in recruiting Dot1a to repress basal and aldosterone-sensitive αENaC transcription and that Dot1l inactivation promotes αENaC mRNA expression by eliminating Dot1a-mediated repression.

Solution structure of the Taf14 YEATS domain and its roles in cell growth of Saccharomyces cerevisiae

2011 ◽  
Vol 436 (1) ◽  
pp. 83-90 ◽  
Author(s):  
Wen Zhang ◽  
Jiahai Zhang ◽  
Xuecheng Zhang ◽  
Chao Xu ◽  
Xiaoming Tu
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Cell Growth ◽  
Transcriptional Activation ◽  
Solution Structure ◽  
Protein Complexes ◽  
Domain Family ◽  
Functional Studies ◽  
C Terminus ◽  
Eukaryotic Species ◽  
Negative Role

Chromatin modifications play important roles in cellular biological process. A novel conserved domain family, YEATS, has been discovered in a variety of eukaryotic species ranging from yeasts to humans. Taf14, which is involved in a few protein complexes of chromatin remodelling and gene transcription, and is essential for keeping chromosome stability, regular cell growth and transcriptional regulation, contains a YEATS domain at its N-terminus. In the present study, we determined the solution structure of the Taf14 YEATS domain using NMR spectroscopy. The Taf14 YEATS domain adopts a global fold of an elongated β-sandwich, similar to the Yaf9 YEATS domain. However, the Taf14 YEATS domain differs significantly from the Yaf9 YEATS domain in some aspects, which might indicate different structural classes of the YEATS domain family. Functional studies indicate that the YEATS domain is critical for the function of Taf14 in inhibiting cell growth under stress conditions. In addition, our results show that the C-terminus of Taf14 is responsible for its interaction with Sth1, which is an essential component of the RSC complex. Taken together, this implies that Taf14 is involved in transcriptional activation of Saccharomyces cerevisiae and the YEATS domain of Taf14 might play a negative role in cell growth.

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