Inducible transcriptional activity of bcn-1 element from  laminin γ1-chain gene promoter in renal and nonrenal cells

Laminin is a major component of the extracellular matrix whose expression is regulated by growth factors. The laminin γ1-chain promoter contains a newly identified transcriptional element denoted bcn-1 that is both active and inducible in mesangial cells. In this study, we explored activation of the bcn-1 element in other renal and nonrenal cells. Treatment of rat glomerular epithelial cells (GEC) with phorbol 12-myristate 13-acetate (PMA) increased activity of the bcn-1 transcriptional element, within the context of the native laminin γ1-chain promoter or when cloned upstream of a heterologous promoter. Treatment of GEC with PMA induced nuclear DNA-binding activity, BCN-1, which was recognized by the bcn-1 motif in a gel shift assay. These results provide evidence that the bcn-1 motif and its cognate BCN-1 factor(s) may regulate transcription of the laminin γ1-chain in GEC. The bcn-1 element and its cognate BCN-1 DNA-binding activity were also inducible in monkey kidney COS-7 and in human T cell Jurkat lines. SDS-PAGE of in situ ultraviolet cross-linked nucleoproteins from GEC, COS, and Jurkat cells revealed one major 110–115 kDa adduct in all three cell lines. These results demonstrate that the bcn-1 element is active in renal and nonrenal cells from different mammalian species where the same protein contributes to the inducible BCN-1 DNA-binding activity.

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Human T-cell lymphotropic virus oncoprotein Tax represses TGF-β1 signaling in human T cells via c-Jun activation: a potential mechanism of HTLV-I leukemogenesis

Blood ◽

10.1182/blood-2001-12-0372 ◽

2002 ◽

Vol 100 (12) ◽

pp. 4129-4138 ◽

Cited By ~ 66

Author(s):

Bertrand Arnulf ◽

Aude Villemain ◽

Christophe Nicot ◽

Elodie Mordelet ◽

Pierre Charneau ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Dna Binding ◽

Binding Activity ◽

T Cell Leukemia ◽

Cell Leukemia ◽

Dna Binding Activity ◽

Human T Cell ◽

Peripheral T Cells ◽

Tgf Β1

Human T-cell leukemia virus I is the etiologic agent of adult T-cell leukemia (ATL), an aggressive T-cell malignancy. The viral oncoprotein Tax, through the activation of nuclear factorκB (NF-κB), CCAAT-enhancer binding protein (CREB), and activated protein-1 (AP-1) pathways, is a transcriptional regulator of critical genes for T-cell homeostasis. In ATL cells, activated AP-1 complexes induce the production of transforming growth factor β1 (TGF-β1). TGF-β1 is an inhibitor of T-cell proliferation and cytotoxicity. Here we show that, in contrast to normal peripheral T cells, ATL cells are resistant to TGF-β1–induced growth inhibition. The retroviral transduction of the Tax protein in peripheral T cells resulted in the loss of TGF-β1 sensitivity. Transient transfection of Tax in HepG2 cells specifically inhibited Smad/TGF-β1 signaling in a dose-dependent manner. In the presence of Tax transfection, increasing amounts of Smad3 restored TGF-β1 signaling. Tax mutants unable to activate NF-κB or CREB pathways were also able to repress Smad3 transcriptional activity. Next we have demonstrated that Tax inhibits TGF-β1 signaling by reducing the Smad3 DNA binding activity. However, Tax did not decrease the expression and the nuclear translocation of Smad3 nor did it interact physically with Smad3. Rather, Tax induced c-Jun N-terminal kinase (JNK) activity and c-Jun phosphorylation, leading to the formation of Smad3/c-Jun complexes. Whereas c-Jun alone abrogates Smad3 DNA binding, cotransfection of Tax and of a dominant-negative form of JNK or a c-Jun antisense-restored Smad3 DNA binding activity and TGF-β1 responsiveness. In ATL and in normal T cells transduced by Tax, c-Jun was constitutively phosphorylated. Thus, we describe a new function of Tax, as a repressor of TGF-β1 signaling through JNK/c-Jun constitutive activation, which may play a critical role in ATL leukemogenesis.

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Repressor Activity of SqrR, a Master Regulator of Persulfide-Responsive Genes, Is Regulated by Heme Coordination

Plant and Cell Physiology ◽

10.1093/pcp/pcaa144 ◽

2020 ◽

Author(s):

Takayuki Shimizu ◽

Yuuki Hayashi ◽

Munehito Arai ◽

Shawn E McGlynn ◽

Tatsuru Masuda ◽

...

Keyword(s):

Dna Binding ◽

Transcriptional Repression ◽

Structural Changes ◽

Gene Promoter ◽

Binding Activity ◽

Heme Binding ◽

Master Regulator ◽

Incremental Change ◽

Dna Binding Activity

Abstract Reactive sulfur species (RSS) are involved in bioactive regulation via persulfidation of proteins. However, how cells regulate RSS-based signaling and RSS metabolism is poorly understood, despite the importance of universal regulation systems in biology. We previously showed that the persulfide-responsive transcriptional factor SqrR acts as a master regulator of sulfide-dependent photosynthesis in proteobacteria. Here, we demonstrated that SqrR also binds heme at a near one-to-one ratio with a binding constant similar to other heme-binding proteins. Heme does not change the DNA-binding pattern of SqrR to the target gene promoter region; however, DNA-binding affinity of SqrR is reduced by the binding of heme, altering its regulatory activity. Circular dichroism spectroscopy clearly showed secondary structural changes in SqrR by the heme binding. Incremental change in the intracellular heme concentration is associated with small, but significant reduction in the transcriptional repression by SqrR. Overall, these results indicate that SqrR has an ability to bind heme to modulate its DNA-binding activity, which may be important for the precise regulation of RSS metabolism in vivo.

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Activation of a Nuclear DNA-binding Protein Recognized by a Transcriptional Element, bcn-1, from the Laminin B2 Chain Gene Promoter

Journal of Biological Chemistry ◽

10.1074/jbc.271.31.18981 ◽

1996 ◽

Vol 271 (31) ◽

pp. 18981-18988 ◽

Cited By ~ 9

Author(s):

Hideaki Suzuki ◽

Bruce C. O'Neill ◽

Yu Suzuki ◽

Oleg N. Denisenko ◽

Karol Bomsztyk

Keyword(s):

Dna Binding ◽

Nuclear Dna ◽

Binding Protein ◽

Gene Promoter ◽

Dna Binding Protein ◽

Chain Gene

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Expression of Pit-1 and related proteins in diverse human pituitary adenomas

Journal of Molecular Endocrinology ◽

10.1677/jme.0.0110283 ◽

1993 ◽

Vol 11 (3) ◽

pp. 283-290 ◽

Cited By ~ 9

Author(s):

N Hoggard ◽

K Callaghan ◽

A Levy ◽

J R E Davis

Keyword(s):

Dna Binding ◽

Pituitary Adenomas ◽

Target Genes ◽

Gene Promoter ◽

Specific Protein ◽

Binding Activity ◽

Mobility Shift ◽

Human Pituitary ◽

Dna Binding Activity ◽

Human Pituitary Adenomas

ABSTRACT Pit-1, a member of the POU family of homeodomain transcription factors, activates prolactin and GH gene expression but also has a role in pituitary cell differentiation and proliferation. Expression of Pit-1 may therefore be of central importance in the function and phenotype of human pituitary adenomas. We have found evidence that, in addition to Pit-1 mRNA, Pit-1-like immunoreactivity and DNA-binding activity are readily detectable in a series of human pituitary adenomas. Gel mobility shift assays using adenoma protein extracts with two Pit-1-binding sites from the human prolactin gene promoter demonstrated the formation of several DNA sequence-specific protein—DNA complexes; some of these could be accounted for by Oct-1-binding activity. Pit-1 activity was anticipated in prolactin- and GH-secreting adenomas, but was also detected in a proportion of endocrine-inactive (non-secreting) adenomas that did not express Pit-1 target genes. The data demonstrate the presence of Pit-1 in a range of pituitary adenomas. Different adenomas generated slightly differing patterns of DNA-binding activity, though Pit-1 mRNA and protein size appeared normal in all tumours so far examined.

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A pathogen- and salicylic acid-induced WRKY DNA-binding activity recognizes the elicitor response element of the tobacco class I chitinase gene promoter

The Plant Journal ◽

10.1046/j.1365-313x.1999.00437.x ◽

1999 ◽

Vol 18 (2) ◽

pp. 141-149 ◽

Cited By ~ 106

Author(s):

Peizhen Yang ◽

Chunhong Chen ◽

Zeping Wang ◽

Baofang Fan ◽

Zhixiang Chen

Keyword(s):

Salicylic Acid ◽

Dna Binding ◽

Gene Promoter ◽

Binding Activity ◽

Chitinase Gene ◽

Class I ◽

Response Element ◽

Dna Binding Activity ◽

Elicitor Response

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The MMSET Protein Is Tightly Associated with Chromatin, Mediates Methylation of Specific Histone Residues and Forms a Complex with a Histone Demethylase.

Blood ◽

10.1182/blood.v108.11.730.730 ◽

2006 ◽

Vol 108 (11) ◽

pp. 730-730

Author(s):

Jotin Marango ◽

Boris A. Leibovitch ◽

Manabu Shimoyama ◽

Hitomi Nishio ◽

Samuel Waxman ◽

...

Keyword(s):

Dna Binding ◽

B Cell ◽

Cell Line ◽

Dna Sequences ◽

Cpg Island ◽

Regulatory Elements ◽

Binding Activity ◽

Chain Gene ◽

Pwwp Domain ◽

Dna Binding Activity

Abstract Over 40% of cases of multiple myeloma (MM) are associated with translocations of the immunoglobulin heavy (IgH) chain gene. The t(4;14) translocation, present in ca. 15% of myeloma cases, results in the overexpression of two potential oncogenes, MMSET and FGFR3, via juxtaposition of their endogenous promoters to regulatory elements of the IgH locus. The presence of t(4;14) and MMSET overexpression are adverse prognostic factors in MM irrespective of FGFR3 expression, implicating MMSET in disease pathogenesis. We previously reported the presence of repression domains and the ability of MMSET to methylate histones. Examination of a number of MMSET isoforms generated by different chromosomal breakpoints in the t(4;14) translocation indicated that a N-terminal portion of the protein containing a PWWP domain mediated tight association of MMSET with chromatin. To determine if this region of the protein could mediate DNA binding we incubated bacterially expressed MMSET with DNA cellulose. Both the N-terminal and C-terminal portions of the protein showed DNA binding activity with different affinities. To isolate DNA sequences potentially bound by MMSET we incubated immunoprecipitated MMSET with a library of human CpG island DNA fragments, selected the bound DNA and performed several rounds of re-amplification and binding of selected sequences. A small family of clones was obtained, having several sequence motifs in common, suggesting specific DNA binding activity by the MMSET complex. The C-terminal region of MMSET containing a SET domain and a PHD finger, in addition to binding naked DNA, bound to native histones H3 and H4. These data suggest that MMSET may specifically target particular genes through recognition of DNA sequences and histones, or possibly specific histone modifications. Subsequently, MMSET may regulate these genes by further modifying the adjacent chromatin. In vitro analysis showed that recombinant MMSET could methylate several lysine residues on core histones, including H3K4, H3K36 and H4K20. However, MMSET immunopurified from a t(4;14)-positive myeloma cell line was only able to methylate histone H4. Additionally, a B-cell line engineered to overexpress MMSET in a conditional manner showed a global increase in the level of tri-methylated H4K20 and modulation of specific sets of genes involved in apoptosis. To determine if MMSET could indeed affect the chromatin configuration of a model gene, MMSET was fused to the Gal4 DNA binding domain and expressed in cells harboring a chromatin-embedded Gal4 reporter. MMSET repressed this reporter and chromatin immunoprecipitation demonstrated that this was accompanied by an increase in H4K20 tri-methylation. Finally, we found that endogenous MMSET could complex with Lysine-Specific Demethylase 1 (LSD1). Accordingly, the targeting of MMSET to the Gal4 reporter gene also led to a loss of H3K4 methylation, consistent with transcriptional repression. Collectively these data indicate that MMSET is a transcriptional effector that can target specific segments of chromatin and mediate a series of repressive changes. Misexpression of MMSET may lead to significant genetic re-programming of the B cell and contribute to myeloma development.

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Estradiol upregulates mesangial cell MMP-2 activity via the transcription factor AP-2

AJP Renal Physiology ◽

10.1152/ajprenal.0318.2000 ◽

2002 ◽

Vol 282 (1) ◽

pp. F164-F169 ◽

Cited By ~ 59

Author(s):

Michael Guccione ◽

Sharon Silbiger ◽

Jun Lei ◽

Joel Neugarten

Keyword(s):

Transcription Factor ◽

Dna Binding ◽

Protein Expression ◽

Mesangial Cell ◽

Mesangial Cells ◽

Binding Activity ◽

Dependent Manner ◽

Protein Levels ◽

Dna Binding Activity ◽

Metalloproteinase Activity

The accumulation of extracellular matrix in the glomerular mesangium reflects the net balance between the synthesis and degradation of matrix components. We have shown that estradiol suppresses the synthesis of types I and IV collagen by cultured mesangial cells (Kwan G, Neugarten J, Sherman M, Ding Q, Fotadar U, Lei J, and Silbiger S. Kidney Int 50: 1173–1179, 1996; Neugarten J, Acharya A, Lei J, and Silbiger S. Am J Physiol Renal Physiol 279: F309–F318, 2000; Neugarten J, Medve I, Lei J, and Silbiger SR. Am J Physiol Renal Physiol 277: F1–F8, 1999; Neugarten J and Silbiger S. Am J Kidney Dis 26: 147–151, 1995; Silbiger S, Lei J, and Neugarten J. Kidney Int 55: 1268–1276, 1998; Silbiger S, Lei J, Ziyadeh FN, and Neugarten J. Am J Physiol Renal Physiol 274: F1113–F1118, 1998). In the present study, we evaluated the effects of sex hormones on the activity of matrix metalloproteinase-2 (MMP-2) in murine mesangial cells, the synthesis of which is regulated by the transcription factor activator protein-2 (AP-2). Estradiol stimulated MMP-2 activity by increasing MMP-2 protein levels in a dose-dependent manner. These effects occurred at physiological concentrations of estradiol and were receptor mediated. Estradiol also increased AP-2 protein levels and increased binding of mesangial cell nuclear extracts to an AP-2 consensus binding sequence oligonucleotide. The ability of estradiol to increase AP-2 protein expression, AP-2/DNA binding activity, MMP-2 protein expression, and metalloproteinase activity was reversed by PD-98059, a selective inhibitor of the extracellular signal-regulated kinase/mitogen-activated protein kinase (ERK/MAPK) signaling cascade. We conclude that estradiol upregulates the MAPK cascade, which in turn stimulates the synthesis of AP-2 protein. The resultant increased AP-2/DNA binding activity leads to increased synthesis of MMP-2 and increased metalloproteinase activity. Stimulation of metalloproteinase activity by estradiol may contribute to the protective effect of female gender on renal disease progression.

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Bradykinin stimulates c-fos expression, AP-1-DNA binding activity and proliferation of rat glomerular mesangial cells

Kidney International ◽

10.1038/ki.1996.505 ◽

1996 ◽

Vol 50 (6) ◽

pp. 1850-1855 ◽

Cited By ~ 24

Author(s):

Samir S. El-Dahr ◽

Susana Dipp ◽

Igor V. Yosipiv ◽

William H. Baricos

Keyword(s):

Dna Binding ◽

Mesangial Cells ◽

Binding Activity ◽

Glomerular Mesangial Cells ◽

Dna Binding Activity ◽

Fos Expression

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DNA-binding activity of LndI protein and temporal expression of the gene that upregulates landomycin E production in Streptomyces globisporus 1912

Microbiology ◽

10.1099/mic.0.27244-0 ◽

2005 ◽

Vol 151 (1) ◽

pp. 281-290 ◽

Cited By ~ 21

Author(s):

Yu. Rebets ◽

B. Ostash ◽

A. Luzhetskyy ◽

S. Kushnir ◽

M. Fukuhara ◽

...

Keyword(s):

Dna Binding ◽

Fluorescent Protein ◽

Solid Phase ◽

Gene Promoter ◽

Binding Activity ◽

Mobility Shift ◽

Chitin Binding Domain ◽

Dna Binding Activity ◽

Gel Mobility Shift

The gene lndI is involved in the pathway-specific positive regulation of biosynthesis of the antitumour polyketide landomycin E in Streptomyces globisporus 1912. LndI was overexpressed in Escherichia coli as a protein C-terminally fused to the intein-chitin-binding-domain tag and purified in a one-step column procedure. Results of in vivo LndI titration, DNA gel mobility-shift assays and promoter-probing experiments indicate that LndI is an autoregulatory DNA-binding protein that binds to its own gene promoter and to the promoter of the structural gene lndE. Enhanced green fluorescent protein was used as a reporter to study the temporal and spatial pattern of lndI transcription. Expression of lndI started before cells entered mid-exponential phase and peak expression coincided with maximal accumulation of landomycin E and biomass. In solid-phase analysis, lndI expression was evident in substrate mycelia but was absent from aerial hyphae and spores.

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