scholarly journals Augmented DNA-binding activity of p53 protein encoded by a carboxyl-terminal alternatively spliced mRNA is blocked by p53 protein encoded by the regularly spliced form.

1995 ◽  
Vol 92 (15) ◽  
pp. 6842-6846 ◽  
Author(s):  
R. Wolkowicz ◽  
A. Peled ◽  
N. B. Elkind ◽  
V. Rotter
Keyword(s):  
Dna Binding ◽  
P53 Protein ◽  
Binding Activity ◽  
Dna Binding Activity ◽  
Alternatively Spliced ◽  
Carboxyl Terminal

scholarly journals Structure of the p53/RNA polymerase II assembly

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Shu-Hao Liou ◽  
Sameer K. Singh ◽  
Robert H. Singer ◽  
Robert A. Coleman ◽  
Wei-Li Liu
Keyword(s):  
Dna Binding ◽  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Conformational Changes ◽  
P53 Protein ◽  
Binding Activity ◽  
Transactivation Domain ◽  
Pol Ii ◽  
Dna Binding Activity ◽  
Regulated Gene Expression

AbstractThe tumor suppressor p53 protein activates expression of a vast gene network in response to stress stimuli for cellular integrity. The molecular mechanism underlying how p53 targets RNA polymerase II (Pol II) to regulate transcription remains unclear. To elucidate the p53/Pol II interaction, we have determined a 4.6 Å resolution structure of the human p53/Pol II assembly via single particle cryo-electron microscopy. Our structure reveals that p53’s DNA binding domain targets the upstream DNA binding site within Pol II. This association introduces conformational changes of the Pol II clamp into a further-closed state. A cavity was identified between p53 and Pol II that could possibly host DNA. The transactivation domain of p53 binds the surface of Pol II’s jaw that contacts downstream DNA. These findings suggest that p53’s functional domains directly regulate DNA binding activity of Pol II to mediate transcription, thereby providing insights into p53-regulated gene expression.

scholarly journals CP-31398 Restores DNA-binding Activity to Mutant p53in Vitrobut Does Not Affect p53 Homologs p63 and p73

2004 ◽  
Vol 279 (44) ◽  
pp. 45887-45896 ◽  
Author(s):  
Mark J. Demma ◽  
Serena Wong ◽  
Eugene Maxwell ◽  
Bimalendu Dasmahapatra
Keyword(s):  
Dna Binding ◽  
Mammalian Cells ◽  
P53 Protein ◽  
Binding Activity ◽  
Mutant P53 ◽  
Dependent Manner ◽  
Wild Type ◽  
Dna Binding Activity

The p53 protein plays a major role in the maintenance of genome stability in mammalian cells. Mutations of p53 occur in over 50% of all cancers and are indicative of highly aggressive cancers that are hard to treat. Recently, there has been a high degree of interest in therapeutic approaches to restore growth suppression functions to mutant p53. Several compounds have been reported to restore wild type function to mutant p53. One such compound, CP-31398, has been shown effectivein vivo, but questions have arisen to whether it actually affects p53. Here we show that mutant p53, isolated from cells treated with CP-31398, is capable of binding to p53 response elementsin vitro. We also show the compound restores DNA-binding activity to mutant p53 in cells as determined by a chromatin immunoprecipitation assay. In addition, using purified p53 core domain from two different hotspot mutants (R273H and R249S), we show that CP-31398 can restore DNA-binding activity in a dose-dependent manner. Using a quantitative DNA binding assay, we also show that CP-31398 increases significantly the amount of mutant p53 that binds to cognate DNA (Bmax) and its affinity (Kd) for DNA. The compound, however, does not affect the affinity (Kdvalue) of wild type p53 for DNA and only increasesBmaxslightly. In a similar assay PRIMA1 does not have any effect on p53 core DNA-binding activity. We also show that CP-31398 had no effect on the DNA-binding activity of p53 homologs p63 and p73.

scholarly journals Redox and Light Control the Heme-Sensing Activity of AppA

mBio ◽  
2013 ◽  
Vol 4 (5) ◽  
Author(s):  
Liang Yin ◽  
Vladimira Dragnea ◽  
George Feldman ◽  
Loubna A. Hammad ◽  
Jonathan A. Karty ◽  
...  
Keyword(s):  
Dna Binding ◽  
Redox State ◽  
Photosynthetic Bacteria ◽  
Disulfide Bridge ◽  
Binding Activity ◽  
Heme Binding ◽  
Tetrapyrrole Biosynthesis ◽  
Dna Binding Activity ◽  
Carboxyl Terminal ◽  
Better Than

ABSTRACT The DNA binding activity of the photosystem-specific repressor PpsR is known to be repressed by the antirepressor AppA. AppA contains a blue-light-absorbing BLUF domain and a heme-binding SCHIC domain that controls the interaction of AppA with PpsR in response to light and heme availability. In this study, we have solved the structure of the SCHIC domain and identified the histidine residue that is critical for heme binding. We also demonstrate that dark-adapted AppA binds heme better than light-excited AppA does and that heme bound to the SCHIC domain significantly reduces the length of the BLUF photocycle. We further show that heme binding to the SCHIC domain is affected by the redox state of a disulfide bridge located in the Cys-rich carboxyl-terminal region. These results demonstrate that light, redox, and heme are integrated inputs that control AppA’s ability to disrupt the DNA binding activity of PpsR. IMPORTANCE Photosynthetic bacteria must coordinate synthesis of the tetrapyrroles cobalamin, heme, and bacteriochlorophyll, as overproduction of the latter two is toxic to cells. A key regulator controlling tetrapyrrole biosynthesis is PpsR, and the activity of PpsR is controlled by the heme-binding and light-regulated antirepressor AppA. We show that AppA binds heme only under dark conditions and that heme binding significantly affects the length of the AppA photocycle. Since AppA interacts with PpsR only in the dark, bound heme thus stimulates the antirepressor activity of PpsR. This causes the redirection of tetrapyrrole biosynthesis away from heme into the bacteriochlorophyll branch.

Modulation of p53 protein conformation and DNA-binding activity by intracellular chelation of zinc

1998 ◽  
Vol 21 (3) ◽  
pp. 205-214 ◽  
Author(s):  
Gerald W. Verhaegh ◽  
Marie-Odile Parat ◽  
Marie-Jeanne Richard ◽  
Pierre Hainaut
Keyword(s):  
Dna Binding ◽  
Protein Conformation ◽  
P53 Protein ◽  
Binding Activity ◽  
Dna Binding Activity

One exon of the human LSF gene includes conserved regions involved in novel DNA-binding and dimerization motifs

1994 ◽  
Vol 14 (8) ◽  
pp. 5076-5087
Author(s):  
M K Shirra ◽  
Q Zhu ◽  
H C Huang ◽  
D Pallas ◽  
U Hansen
Keyword(s):  
Transcription Factor ◽  
Dna Binding ◽  
Simian Virus 40 ◽  
Simian Virus ◽  
Binding Activity ◽  
Protein Protein Interaction ◽  
Dna Binding Activity ◽  
Dna Binding Sites ◽  
Alternative Mrna Splicing ◽  
Alternatively Spliced

The transcription factor LSF, identified as a HeLa protein that binds the simian virus 40 late promoter, recognizes direct repeats with a center-to-center spacing of 10 bp. The characterization of two human cDNAs, representing alternatively spliced mRNAs, provides insight into the unusual DNA-binding and oligomerization properties of LSF. The sequence of the full-length LSF is identical to that of the transcription factors alpha CP2 and LBP-1c and has similarity to the Drosophila transcription factor Elf-1/NTF-1. Using an epitope-counting method, we show that LSF binds DNA as a homodimer. LSF-ID, which is identical to LBP-1d, contains an in-frame internal deletion of 51 amino acids resulting from alternative mRNA splicing. Unlike LSF, LSF-ID did not bind LSF DNA-binding sites. Furthermore, LSF-ID did not affect the binding of LSF to DNA, suggesting that the two proteins do not interact. Of three short regions with a high degree of homology between LSF and Elf-1/NTF-1, LSF-ID lacks two, which are predicted to form beta-strands. Double amino acid substitutions in each of these regions eliminated specific DNA-binding activity, similarly to the LSF-ID deletion. The dimerization potential of these mutants was measured both by the ability to inhibit the binding of LSF to DNA and by direct protein-protein interaction studies. Mutations in one homology region, but not the other, functionally eliminated dimerization.

Cysteine residues in the zinc finger and amino acids adjacent to the finger are necessary for DNA binding by the LAC9 regulatory protein of Kluyveromyces lactis

1988 ◽  
Vol 8 (9) ◽  
pp. 3726-3733
Author(s):  
M M Witte ◽  
R C Dickson
Keyword(s):  
Amino Acid ◽  
Dna Binding ◽  
Zinc Finger ◽  
Kluyveromyces Lactis ◽  
Regulatory Protein ◽  
Binding Activity ◽  
Binding Domain ◽  
Dna Binding Domain ◽  
Dna Binding Activity ◽  
Carboxyl Terminal

LAC9 is a positive regulatory protein that controls transcription of the lactose-galactose regulon in Kluyveromyces lactis. LAC9 is homologous to the GAL4 protein of Saccharomyces cerevisiae. Both proteins have a single "zinc finger" which plays a role in DNA binding. We previously hypothesized (L. V. Wray, M. M. Witte, R. C. Dickson, and M. I. Riley, Mol. Cell. Biol. 7:1111-1121, 1987) that the DNA-binding domain of the LAC9 protein consisted of the zinc finger as well as a region of amino acids on the carboxyl-terminal side of the zinc finger. In this study we used oligonucleotide-directed mutagenesis to introduce 13 single-amino-acid changes into the proposed DNA-binding domain of the LAC9 protein. Variant LAC9 proteins carrying an amino acid substitution in any one of the four highly conserved Cys residues of the zinc finger had reduced DNA-binding activity, suggesting that each Cys is necessary for DNA binding. Three of four variant LAC9 proteins with amino acid substitutions located on the carboxyl-terminal side of the zinc finger had reduced DNA-binding activity. These results support our hypothesis that the DNA-binding domain of the LAC9 protein is composed of the zinc finger and the adjacent region on the carboxyl side of the zinc finger, a region that has the potential to form an alpha-helix. Finally, LAC9 proteins containing His residues substituted for the conserved Cys residues also had reduced DNA-binding activity, indicating that His residues are not equivalent to Cys residues, as had been previously thought.

scholarly journals Hypoxia-Induced Decrease in p53 Protein Level and Increase in c-jun DNA Binding Activity Results in Cancer Cell Resistance to Etoposide

Neoplasia ◽  
2009 ◽  
Vol 11 (10) ◽  
pp. 976-IN3 ◽  
Author(s):  
Jean-Philippe Cosse ◽  
Marie Ronvaux ◽  
Noëlle Ninane ◽  
Martine J. Raes ◽  
Carine Michiels
Keyword(s):  
Dna Binding ◽  
Cancer Cell ◽  
Protein Level ◽  
P53 Protein ◽  
Binding Activity ◽  
Cell Resistance ◽  
Dna Binding Activity

scholarly journals Carboxyl terminal region of the MukB protein in Escherichia coli is essential for DNA binding activity

1996 ◽  
Vol 143 (2-3) ◽  
pp. 211-216 ◽  
Author(s):  
Abu Z.M. Saleh ◽  
Kunitoshi Yamanaka ◽  
Hironori Niki ◽  
Teru Ogura ◽  
Mitsuyoshi Yamazoe ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Dna Binding ◽  
Binding Activity ◽  
Terminal Region ◽  
Dna Binding Activity ◽  
Carboxyl Terminal

scholarly journals Stimulation of p53 DNA Binding by c-Abl Requires the p53 C Terminus and Tetramerization

2000 ◽  
Vol 20 (3) ◽  
pp. 741-748 ◽  
Author(s):  
Ying Nie ◽  
Heng-Hong Li ◽  
Craig M. Bula ◽  
Xuan Liu
Keyword(s):  
Dna Binding ◽  
Binding Activity ◽  
Carboxyl Terminus ◽  
Dependent Manner ◽  
Regulatory Domain ◽  
Dna Binding Activity ◽  
C Terminus ◽  
Carboxyl Terminal ◽  
Dna Complex ◽  
Stimulation Of

ABSTRACT The carboxyl terminus of p53 is a target of a variety of signals for regulation of p53 DNA binding. Growth suppressor c-Abl interacts with p53 in response to DNA damage and overexpression of c-Abl leads to G1 growth arrest in a p53-dependent manner. Here, we show that c-Abl binds directly to the carboxyl-terminal regulatory domain of p53 and that this interaction requires tetramerization of p53. Importantly, we demonstrate that c-Abl stimulates the DNA-binding activity of wild-type p53 but not of a carboxyl-terminally truncated p53 (p53Δ363C). A deletion mutant of c-Abl that does not bind to p53 is also incapable of activating p53 DNA binding. These data suggest that the binding to the p53 carboxyl terminus is necessary for c-Abl stimulation. To investigate the mechanism for this activation, we have also shown that c-Abl stabilizes the p53-DNA complex. These results led us to hypothesize that the interaction of c-Abl with the C terminus of p53 may stabilize the p53 tetrameric conformation, resulting in a more stable p53-DNA complex. Interestingly, the stimulation of p53 DNA-binding by c-Abl does not require its tyrosine kinase activity, indicating a kinase-independent function for c-Abl. Together, these results suggest a detailed mechanism by which c-Abl activates p53 DNA-binding via the carboxyl-terminal regulatory domain and tetramerization.

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