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Formation of chelate structure between His-Met dipeptide and diaqua-cisplatin complex; DFT/PCM computational study. J Biol Inorg Chem 2018; 23:363-376. [DOI: 10.1007/s00775-018-1536-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Accepted: 01/23/2018] [Indexed: 02/01/2023]
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2
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p53 Specifically Binds Triplex DNA In Vitro and in Cells. PLoS One 2016; 11:e0167439. [PMID: 27907175 PMCID: PMC5131957 DOI: 10.1371/journal.pone.0167439] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2016] [Accepted: 11/14/2016] [Indexed: 11/30/2022] Open
Abstract
Triplex DNA is implicated in a wide range of biological activities, including regulation of gene expression and genomic instability leading to cancer. The tumor suppressor p53 is a central regulator of cell fate in response to different type of insults. Sequence and structure specific modes of DNA recognition are core attributes of the p53 protein. The focus of this work is the structure-specific binding of p53 to DNA containing triplex-forming sequences in vitro and in cells and the effect on p53-driven transcription. This is the first DNA binding study of full-length p53 and its deletion variants to both intermolecular and intramolecular T.A.T triplexes. We demonstrate that the interaction of p53 with intermolecular T.A.T triplex is comparable to the recognition of CTG-hairpin non-B DNA structure. Using deletion mutants we determined the C-terminal DNA binding domain of p53 to be crucial for triplex recognition. Furthermore, strong p53 recognition of intramolecular T.A.T triplexes (H-DNA), stabilized by negative superhelicity in plasmid DNA, was detected by competition and immunoprecipitation experiments, and visualized by AFM. Moreover, chromatin immunoprecipitation revealed p53 binding T.A.T forming sequence in vivo. Enhanced reporter transactivation by p53 on insertion of triplex forming sequence into plasmid with p53 consensus sequence was observed by luciferase reporter assays. In-silico scan of human regulatory regions for the simultaneous presence of both consensus sequence and T.A.T motifs identified a set of candidate p53 target genes and p53-dependent activation of several of them (ABCG5, ENOX1, INSR, MCC, NFAT5) was confirmed by RT-qPCR. Our results show that T.A.T triplex comprises a new class of p53 binding sites targeted by p53 in a DNA structure-dependent mode in vitro and in cells. The contribution of p53 DNA structure-dependent binding to the regulation of transcription is discussed.
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3
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Ream JA, Lewis LK, Lewis KA. Rapid agarose gel electrophoretic mobility shift assay for quantitating protein: RNA interactions. Anal Biochem 2016; 511:36-41. [PMID: 27495142 DOI: 10.1016/j.ab.2016.07.027] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Revised: 07/26/2016] [Accepted: 07/28/2016] [Indexed: 11/19/2022]
Abstract
Interactions between proteins and nucleic acids are frequently analyzed using electrophoretic mobility shift assays (EMSAs). This technique separates bound protein:nucleic acid complexes from free nucleic acids by electrophoresis, most commonly using polyacrylamide gels. The current study utilizes recent advances in agarose gel electrophoresis technology to develop a new EMSA protocol that is simpler and faster than traditional polyacrylamide methods. Agarose gels are normally run at low voltages (∼10 V/cm) to minimize heating and gel artifacts. In this study we demonstrate that EMSAs performed using agarose gels can be run at high voltages (≥20 V/cm) with 0.5 × TB (Tris-borate) buffer, allowing for short run times while simultaneously yielding high band resolution. Several parameters affecting band and image quality were optimized for the procedure, including gel thickness, agarose percentage, and applied voltage. Association of the siRNA-binding protein p19 with its target RNA was investigated using the new system. The agarose gel and conventional polyacrylamide gel methods generated similar apparent binding constants in side-by-side experiments. A particular advantage of the new approach described here is that the short run times (5-10 min) reduce opportunities for dissociation of bound complexes, an important concern in non-equilibrium nucleic acid binding experiments.
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Affiliation(s)
- Jennifer A Ream
- Department of Chemistry and Biochemistry, Texas State University, 601 University Dr., San Marcos, TX, 78666, USA
| | - L Kevin Lewis
- Department of Chemistry and Biochemistry, Texas State University, 601 University Dr., San Marcos, TX, 78666, USA
| | - Karen A Lewis
- Department of Chemistry and Biochemistry, Texas State University, 601 University Dr., San Marcos, TX, 78666, USA.
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4
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Němcová K, Sebest P, Havran L, Orság P, Fojta M, Pivoňková H. Electrochemical detection of DNA binding by tumor suppressor p53 protein using osmium-labeled oligonucleotide probes and catalytic hydrogen evolution at the mercury electrode. Anal Bioanal Chem 2014; 406:5843-52. [PMID: 25056872 DOI: 10.1007/s00216-014-7996-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2014] [Revised: 06/22/2014] [Accepted: 06/24/2014] [Indexed: 11/28/2022]
Abstract
In this paper, we present an electrochemical DNA-protein interaction assay based on a combination of protein-specific immunoprecipitation at magnetic beads (MBIP) with application of oligonucleotide (ON) probes labeled with an electroactive oxoosmium complex (Os,bipy). We show that double-stranded ONs bearing a dT20 tail labeled with Os,bipy are specifically recognized by the tumor suppressor p53 protein according to the presence or absence of a specific binding site (p53CON) in the double-stranded segment. We demonstrate the applicability of the Os,bipy-labeled probes in titration as well as competition MBIP assays to evaluate p53 relative affinity to various sequence-specific or structurally distinct unlabeled DNA substrates upon modulation of the p53-DNA binding by monoclonal antibodies used for the immunoprecipitation. To detect the p53-bound osmium-labeled probes, we took advantage of a catalytic peak yielded by Os,bipy-modified DNA at the mercury-based electrodes, allowing facile determination of subnanogram quantities of the labeled oligonucleotides. Versatility of the electrochemical MBIP technique and its general applicability in studies of any DNA-binding protein is discussed.
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Affiliation(s)
- Kateřina Němcová
- Institute of Biophysics, Academy of Sciences of the Czech Republic, v.v.i., Královopolská 135, 612 65, Brno, Czech Republic
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5
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Carminati PO, Donaires FS, Marques MM, Donadi EA, Passos GAS, Sakamoto-Hojo ET. Cisplatin associated with LY294002 increases cytotoxicity and induces changes in transcript profiles of glioblastoma cells. Mol Biol Rep 2013; 41:165-77. [DOI: 10.1007/s11033-013-2849-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2012] [Accepted: 10/29/2013] [Indexed: 02/03/2023]
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6
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Ahmad S. Platinum-DNA interactions and subsequent cellular processes controlling sensitivity to anticancer platinum complexes. Chem Biodivers 2010; 7:543-66. [PMID: 20232326 DOI: 10.1002/cbdv.200800340] [Citation(s) in RCA: 151] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Platinum-based compounds are widely used as chemotherapeutics for the treatment of a variety of cancers. The anticancer activity of cisplatin and other platinum drugs is believed to arise from their interaction with DNA. Several cellular pathways are activated in response to this interaction, which include recognition by high-mobility group and repair proteins, translesion synthesis by polymerases, and induction of apoptosis. The apoptotic process is regulated by activation of caspases, p53 gene, and several proapoptotic and antiapoptotic proteins. Such cellular processing eventually leads to an inhibition of the replication or transcription machinery of the cell. Deactivation of platinum drugs by thiols, increased nucleotide excision repair of Pt-DNA adducts, decreased mismatch repair, and defective apoptosis result in resistance to platinum therapy. The differences in cytotoxicity of various platinum complexes are attributed to the differential recognition of their adducts by cellular proteins. Cisplatin and oxaliplatin both produce mainly 1,2-GG intrastrand cross-links as major adducts, but oxaliplatin is found to be more active particularly against cisplatin-resistant tumor cells. Mismatch repair and replicative bypass appear to be the processes most likely involved in differentiating the molecular responses to these two agents. This review describes the formation of Pt-DNA adducts, their interaction with cellular components, and biological effects of this interaction.
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Affiliation(s)
- Saeed Ahmad
- Department of Chemistry, University of Engineering and Technology, Lahore 54890, Pakistan.
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7
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Zimmermann T, Chval Z, Burda JV. Cisplatin Interaction with Cysteine and Methionine in Aqueous Solution: Computational DFT/PCM Study. J Phys Chem B 2009; 113:3139-50. [DOI: 10.1021/jp807645x] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Tomáš Zimmermann
- Department of Chemical Physics and Optics, Faculty of Mathematics and Physics, Charles University, Ke Karlovu 3, 121 16 Prague 2, Czech Republic, and Department of Biophysics, Faculty of Health and Social Studies, University of South Bohemia, J. Boreckeho 27, 370 11 Ceske Budejovice, Czech Republic
| | - Zdeněk Chval
- Department of Chemical Physics and Optics, Faculty of Mathematics and Physics, Charles University, Ke Karlovu 3, 121 16 Prague 2, Czech Republic, and Department of Biophysics, Faculty of Health and Social Studies, University of South Bohemia, J. Boreckeho 27, 370 11 Ceske Budejovice, Czech Republic
| | - Jaroslav V. Burda
- Department of Chemical Physics and Optics, Faculty of Mathematics and Physics, Charles University, Ke Karlovu 3, 121 16 Prague 2, Czech Republic, and Department of Biophysics, Faculty of Health and Social Studies, University of South Bohemia, J. Boreckeho 27, 370 11 Ceske Budejovice, Czech Republic
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8
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Affiliation(s)
- Yongwon Jung
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139-4307, USA
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9
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Pivonková H, Pecinka P, Cesková P, Fojta M. DNA modification with cisplatin affects sequence-specific DNA binding of p53 and p73 proteins in a target site-dependent manner. FEBS J 2006; 273:4693-706. [PMID: 16981908 DOI: 10.1111/j.1742-4658.2006.05472.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Proteins p53 and p73 act as transcription factors in cell cycle control, regulation of cell development and/or in apoptotic pathways. Both proteins bind to response elements (p53 DNA-binding sites), typically consisting of two copies of a motif RRRCWWGYYY. It has been demonstrated previously that DNA modification with the antitumor drug cisplatin inhibits p53 binding to a synthetic p53 DNA-binding site. Here we demonstrate that the effects of global DNA modification with cisplatin on binding of the p53 or p73 proteins to various p53 DNA-binding sites differed significantly, depending on the nucleotide sequence of the given target site. The relative sensitivities of protein-DNA binding to cisplatin DNA treatment correlated with the occurrence of sequence motifs forming stable bifunctional adducts with the drug (namely, GG and AG doublets) within the target sites. Binding of both proteins to mutated p53 DNA-binding sites from which these motifs had been eliminated was only negligibly affected by cisplatin treatment, suggesting that formation of the cisplatin adducts within the target sites was primarily responsible for inhibition of the p53 or p73 sequence-specific DNA binding. Distinct effects of cisplatin DNA modification on the recognition of different response elements by the p53 family proteins may have impacts on regulation pathways in cisplatin-treated cells.
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Affiliation(s)
- Hana Pivonková
- Institute of Biophysics, Academy of Sciences of the Czech Republic, Brno, Czech Republic
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10
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Stehlíková K, Kaspárková J, Nováková O, Martínez A, Moreno V, Brabec V. Recognition of DNA modified by trans-[PtClNH(4-hydroxymethylpyridine)] by tumor suppressor protein p53 and character of DNA adducts of this cytotoxic complex. FEBS J 2006; 273:301-14. [PMID: 16403018 DOI: 10.1111/j.1742-4658.2005.05061.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
trans-[PtCl(2)NH(3)(4-Hydroxymethylpyridine)] (trans-PtHMP) is an analogue of clinically ineffective transplatin, which is cytotoxic in the human leukemia cancer cell line. As DNA is a major pharmacological target of antitumor platinum compounds, modifications of DNA by trans-PtHMP and recognition of these modifications by active tumor suppressor protein p53 were studied in cell-free media using the methods of molecular biology and biophysics. Our results demonstrate that the replacement of the NH(3) group in transplatin by the 4-hydroxymethylpyridine ligand affects the character of DNA adducts of parent transplatin. The binding of trans-PtHMP is slower, although equally sequence-specific. This platinum complex also forms on double-stranded DNA stable intrastrand and interstrand cross-links, which distort DNA conformation in a unique way. The most pronounced conformational alterations are associated with a local DNA unwinding, which was considerably higher than those produced by other bifunctional platinum compounds. DNA adducts of trans-PtHMP also reduce the affinity of the p53 protein to its consensus DNA sequence. Thus, downstream effects modulated by recognition and binding of p53 protein to DNA distorted by trans-PtHMP and transplatin are not likely to be the same. It has been suggested that these different effects may contribute to different antitumor effects of these two transplatinum compounds.
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Affiliation(s)
- Kristýna Stehlíková
- Institute of Biophysics, Academy of Sciences of the Czech Republic, Brno, Czech Republic
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11
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Pivonková H, Brázdová M, Kaspárková J, Brabec V, Fojta M. Recognition of cisplatin-damaged DNA by p53 protein: Critical role of the p53 C-terminal domain. Biochem Biophys Res Commun 2006; 339:477-84. [PMID: 16300733 DOI: 10.1016/j.bbrc.2005.11.038] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2005] [Accepted: 11/03/2005] [Indexed: 11/21/2022]
Abstract
It was shown previously that the p53 protein can recognize DNA modified with antitumor agent cisplatin (cisPt-DNA). Here, we studied p53 binding to the cisPt-DNA using p53 deletion mutants and via modulation of the p53-DNA binding by changes of the protein redox state. Isolated p53 C-terminal domain (CTD) bound to the cisPt-DNA with a significantly higher affinity than to the unmodified DNA. On the other hand, p53 constructs involving the core domain but lacking the C-terminal DNA binding site (CTDBS) exhibited only small binding preference for the cisPt-DNA. Oxidation of cysteine residues within the CD of posttranslationally unmodified full length p53 did not affect its ability to recognize cisPt-DNA. Blocking of the p53 CTDBS by a monoclonal antibody Bp53-10.1 resulted in abolishment of the isolated CTD binding to the cisPt-DNA. Our results demonstrate a crucial role of the basic region of the p53 CTD (aa 363-382) in the cisPt-DNA recognition.
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Affiliation(s)
- Hana Pivonková
- Institute of Biophysics, Academy of Sciences of the Czech Republic, Královopolská 135, 612 65 Brno, Czech Republic
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12
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Cherny DI, Brázdova M, Palecek J, Palecek E, Jovin TM. Sequestering of p53 into DNA-protein filaments revealed by electron microscopy. Biophys Chem 2005; 114:261-71. [PMID: 15829361 DOI: 10.1016/j.bpc.2004.12.042] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2004] [Revised: 12/17/2004] [Accepted: 12/17/2004] [Indexed: 11/25/2022]
Abstract
Using electron microscopy, we analyzed the interaction of bacterially expressed full-length p53, p53(1-393), and its C-terminal fragment, p53(320-393), with long (approximately 3000 bp) dsDNA in linear and supercoiled (|DeltaLk| approximately 4-6) forms containing or lacking the p53 recognition sequence (p53CON). The main structural feature of the complexes formed by either protein was a DNA-protein filament, in which two DNA duplexes are linked (synapsed) via bound protein tetramers. The efficiency of the synapse, reflected in its length and the fraction of molecules exhibiting DNA-protein filaments, was significantly modulated by the molecular form of the protein and the topological state of the DNA. With linear DNA, the synapse yield promoted by the C-terminus fragment was very low, but the full-length protein was effective in linking noncontiguous duplexes, leading to the formation of intramolecular loops constrained at their bases by short regions of synapsed DNA duplexes. When the linear DNA contained p53CON, regions of preferential sequence, i.e., encompassing p53CON and probably p53CON-like sequences, were predominantly synapsed, indicating a sequence specificity of the p53 core domain. With scDNA, the synapse yield was significantly higher compared to the linear counterparts and was weakly dependent on the sign of superhelicity and presence or absence of p53CON. However, the full-length protein was more effective in promoting DNA synapses compared to the C-terminal fragment. The overall structure of the DNA-protein filaments was apparently similar for either protein form, although the apparent width differed slightly (approximately 7-9 nm and approximately 10-12 nm for p53(320-393) and p53(1-393), respectively). No distortion of the DNA helices involved in the synapse was found. We conclude that the structural similarity of DNA-protein filaments observed for both proteins is attributable mainly to the C-terminus, and that the yield is dictated by the specific and possibly nonspecific interactions of the core domain in combination with DNA topology. Possible implications for the sequestering of p53 in DNA-protein filaments are discussed.
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Affiliation(s)
- Dmitry I Cherny
- Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
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13
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Sawicka M, Kalinowska M, Skierski J, Lewandowski W. A review of selected anti-tumour therapeutic agents and reasons for multidrug resistance occurrence. J Pharm Pharmacol 2004; 56:1067-81. [PMID: 15324475 DOI: 10.1211/0022357044265] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
It is assumed that proteins from the ABC family (i.e., glycoprotein P (Pgp)) and a multidrug resistance associated protein (MRP) play a main role in the occurrence of multidrug resistance (MDR) in tumour cells. Other factors that influence the rise of MDR are mechanisms connected with change in the effectiveness of the glutathione cycle and with decrease in expression of topoisomerases I and II. The aim of this review is to characterize drugs applied in anti-tumour therapy and to describe the present state of knowledge concerning the mechanisms of MDR occurrence, as well as the pharmacological agents applied in reducing this phenomenon.
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Affiliation(s)
- M Sawicka
- Department of Chemistry, Biatystok Technical University, Zamenhofa 29, 15-435 Biatystok, Poland
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Kasparkova J, Fojta M, Farrell N, Brabec V. Differential recognition by the tumor suppressor protein p53 of DNA modified by the novel antitumor trinuclear platinum drug BBR3464 and cisplatin. Nucleic Acids Res 2004; 32:5546-52. [PMID: 15486204 PMCID: PMC524304 DOI: 10.1093/nar/gkh896] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2004] [Revised: 09/07/2004] [Accepted: 09/29/2004] [Indexed: 11/13/2022] Open
Abstract
The trinuclear platinum agent BBR3464, a representative of a new class of anticancer drugs, is more potent than conventional mononuclear cisplatin [cis-diamminedichloroplatinum(II)]. BBR3464 retains significant activity in human tumor cell lines and xenografts that are refractory or poorly responsive to cisplatin, and displays a high activity in human tumor cell lines that are characterized by both wild-type and mutant p53 gene. In contrast, on average, cells with mutant p53 are more resistant to the effect of cisplatin. It has been hypothesized that the sensitivity or resistance of tumor cells to cisplatin might be also associated with cell cycle control and repair processes that involve p53. DNA is a major pharmacological target of platinum compounds and DNA binding activity of the p53 protein is crucial for its tumor suppressor function. This study, using gel-mobility-shift assays, was undertaken to examine the interactions of active and latent p53 protein with DNA fragments and oligodeoxyribonucleotide duplexes modified by BBR3464 in a cell free medium and to compare these results with those describing the interactions of these proteins with DNA modified by cisplatin. The results indicate that structurally different DNA adducts of BBR3464 and cisplatin exhibit a different efficiency to affect the binding affinity of the modified DNA to p53 protein. It has been suggested that different structural perturbations induced in DNA by the adducts of BBR3464 and cisplatin produce a differential response to p53 protein activation and recognition and that a 'molecular approach' to control of downstream effects such as protein recognition and pathways of apoptosis induction may consist in design of structurally unique DNA adducts as cell signals.
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Affiliation(s)
- Jana Kasparkova
- Institute of Biophysics, Academy of Sciences of the Czech Republic, CZ-61265 Brno, Czech Republic
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Fojta M, Pivonkova H, Brazdova M, Nemcova K, Palecek J, Vojtesek B. Investigations of the supercoil-selective DNA binding of wild type p53 suggest a novel mechanism for controlling p53 function. ACTA ACUST UNITED AC 2004; 271:3865-76. [PMID: 15373832 DOI: 10.1111/j.1432-1033.2004.04323.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The tumor suppressor protein, p53, selectively binds to supercoiled (sc) DNA lacking the specific p53 consensus binding sequence (p53CON). Using p53 deletion mutants, we have previously shown that the p53 C-terminal DNA-binding site (CTDBS) is critical for this binding. Here we studied supercoil-selective binding of bacterially expressed full-length p53 using modulation of activity of the p53 DNA-binding domains by oxidation of cysteine residues (to preclude binding within the p53 core domain) and/or by antibodies mapping to epitopes at the protein C-terminus (to block binding within the CTDBS). In the absence of antibody, reduced p53 preferentially bound scDNA lacking p53CON in the presence of 3 kb linear plasmid DNAs or 20 mer oligonucleotides, both containing and lacking the p53CON. Blocking the CTDBS with antibody caused reduced p53 to bind equally to sc and linear or relaxed circular DNA lacking p53CON, but with a high preference for the p53CON. The same immune complex of oxidized p53 failed to bind DNA, while oxidized p53 in the absence of antibody restored selective scDNA binding. Antibodies mapping outside the CTDBS did not prevent p53 supercoil-selective (SCS) binding. These data indicate that the CTDBS is primarily responsible for p53 SCS binding. In the absence of the SCS binding, p53 binds sc or linear (relaxed) DNA via the p53 core domain and exhibits strong sequence-specific binding. Our results support a hypothesis that alterations to DNA topology may be a component of the complex cellular regulatory mechanisms that control the switch between latent and active p53 following cellular stress.
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Affiliation(s)
- Miroslav Fojta
- Laboratory of Biophysical Chemistry and Molecular Oncology, Institute of Biophysics, Academy of Sciences of the Czech Republic, CZ-612 65 Brno, Czech Republic.
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