SCH529074, a Small Molecule Activator of Mutant p53, Which Binds p53 DNA Binding Domain (DBD), Restores Growth-suppressive Function to Mutant p53 and Interrupts HDM2-mediated Ubiquitination of Wild Type p53

We have analyzed the specific interaction of murine p53 with the consensus DNA-binding sequence 5'-AGACATGCCT-AGACATGCCT-3'. We used segments of p53 lacking the C-terminal, nonspecific DNA-binding domain because the presence of an autonomous nonspecific DNA-binding domain in wild-type p53 would complicate analysis of site-specific DNA binding. p53 amino acids 1 to 360 bind the consensus sequence as tetramers, and DNA binding promotes tetramer-tetramer interactions. p53 amino acids 80 to 290, lacking both the nonspecific DNA-binding and tetramerization domains, consistently bind consensus DNA as four monomers and only as four monomers. The virtual absence of stable binding by fewer than four monomers, even at low concentrations of p53, argues that binding by amino acids 80 to 290 is strongly cooperative. Because p53 tetramers and monomers do not simultaneously bind a single DNA consensus sequence, we conclude that a single tetramer of wild-type p53 engages the recognition sequences of the entire DNA consensus site. We further show that consensus DNA consists of two functional half-sites. Insertions, deletions, or rearrangements within the half-sites reduce DNA binding dramatically. In contrast, two half-sites separated by insertions bind p53 relatively efficiently. Insertions that place half-sites on opposite faces of the DNA helix reduce DNA binding more than insertions that place half-sites on the same face of the helix. Transcription studies, in vivo, strongly confirm the rotational specificity of the p53 interaction with consensus DNA. The ability of single p53 tetramers to bind separated DNA half-sites argues that p53 has a flexible tetramerization region.

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Dissection of a carboxy-terminal region of the yeast regulatory protein RAP1 with effects on both transcriptional activation and silencing

Molecular and Cellular Biology ◽

10.1128/mcb.12.3.1209-1217.1992 ◽

1992 ◽

Vol 12 (3) ◽

pp. 1209-1217

Author(s):

C F Hardy ◽

D Balderes ◽

D Shore

Keyword(s):

Dna Binding ◽

Binding Site ◽

Transcriptional Activation ◽

Binding Sites ◽

Binding Protein ◽

Binding Domain ◽

Dominant Negative Effect ◽

Dna Binding Domain ◽

Wild Type ◽

Carboxy Terminal

RAP1 is an essential sequence-specific DNA-binding protein in Saccharomyces cerevisiae whose binding sites are found in a large number of promoters, where they function as upstream activation sites, and at the silencer elements of the HMR and HML mating-type loci, where they are important for repression. We have examined the involvement of specific regions of the RAP1 protein in both repression and activation of transcription by studying the properties of a series of hybrid proteins containing RAP1 sequences fused to the DNA-binding domain of the yeast protein GAL4 (amino acids 1 to 147). GAL4 DNA-binding domain/RAP1 hybrids containing only the carboxy-terminal third of the RAP1 protein (which lacks the RAP1 DNA-binding domain) function as transcriptional activators of a reporter gene containing upstream GAL4 binding sites. Expression of some hybrids from the strong ADH1 promoter on multicopy plasmids has a dominant negative effect on silencers, leading to either partial or complete derepression of normally silenced genes. The GAL4/RAP1 hybrids have different effects on wild-type and several mutated but functional silencers. Silencers lacking either an autonomously replicating sequence consensus element or the RAP1 binding site are strongly derepressed, whereas the wild-type silencer or a silencer containing a deletion of the binding site for another silencer-binding protein, ABF1, are only weakly affected by hybrid expression. By examining a series of GAL4 DNA-binding domain/RAP1 hybrids, we have mapped the transcriptional activation and derepression functions to specific parts of the RAP1 carboxy terminus.(ABSTRACT TRUNCATED AT 250 WORDS)

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A mutant androgen receptor from patients with Reifenstein syndrome: identification of the function of a conserved alanine residue in the D box of steroid receptors

Molecular and Cellular Biology ◽

10.1128/mcb.13.12.7850-7858.1993 ◽

1993 ◽

Vol 13 (12) ◽

pp. 7850-7858

Author(s):

F Kaspar ◽

H Klocker ◽

A Denninger ◽

A C Cato

Keyword(s):

Androgen Receptor ◽

Dna Binding ◽

Steroid Receptors ◽

Regulatory Elements ◽

Binding Domain ◽

Dna Binding Domain ◽

Wild Type ◽

Binding Studies ◽

Mutant Receptor ◽

Alanine Residue

Reifenstein syndrome is an eponymic term that describes partial androgen-insensitive disorders. Androgen receptor isolated from five patients with this syndrome contains a specific mutation in the DNA binding domain of the receptor. This mutation converts an alanine to a threonine at position 596 next to the zinc catenation site at the second finger. The threonine 596 mutant receptor mediated normal androgen response at promoters with closely positioned multiple regulatory elements for the androgen receptor and other transcription factors. Promoters with single isolated androgen response elements were not transactivated by the mutant receptor. In in vitro receptor-DNA binding studies, interaction with DNA by the mutant receptor was achieved only in the presence of an anti-androgen receptor antibody. Exchanging alanine 596 in the wild-type androgen receptor with serine or valine produced mutants with properties indistinguishable from those of the naturally occurring threonine 596 mutant receptor. These results indicate that an alanine residue at position 596 contributes important structural and functional activities to the androgen receptor. In the androgen receptor from the patients with Reifenstein syndrome, in which this alanine is converted to a threonine, wild-type receptor properties can be restored by exchanging an additional threonine at position 602 to an alanine. An alanine residue at position 596 or 602 in the DNA binding domain of the androgen receptor is therefore important for the full function of this receptor. In all steroid receptors that bind the core sequence AGAACANNNTGTTCT, an alanine residue is also present at a position equivalent to alanine 596 in the androgen receptor.

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A single amino acid change in CUP2 alters its mode of DNA binding.

Molecular and Cellular Biology ◽

10.1128/mcb.10.9.4778 ◽

1990 ◽

Vol 10 (9) ◽

pp. 4778-4787 ◽

Cited By ~ 28

Author(s):

C Buchman ◽

P Skroch ◽

W Dixon ◽

T D Tullius ◽

M Karin

Keyword(s):

Amino Acid ◽

Dna Binding ◽

Binding Activity ◽

Binding Domain ◽

Single Amino Acid ◽

Dna Binding Domain ◽

Sequence Motifs ◽

Wild Type ◽

Mobility Shift ◽

Single Amino Acid Change

CUP2 is a copper-dependent transcriptional activator of the yeast CUP1 metallothionein gene. In the presence of Cu+ and Ag+) ions its DNA-binding domain is thought to fold as a cysteine-coordinated Cu cluster which recognizes the palindromic CUP1 upstream activation sequence (UASc). Using mobility shift, methylation interference, and DNase I and hydroxyl radical footprinting assays, we examined the interaction of wild-type and variant CUP2 proteins produced in Escherichia coli with the UASc. Our results suggest that CUP2 has a complex Cu-coordinated DNA-binding domain containing different parts that function as DNA-binding elements recognizing distinct sequence motifs embedded within the UASc. A single-amino-acid substitution of cysteine 11 with a tyrosine results in decreased Cu binding, apparent inactivation of one of the DNA-binding elements and a dramatic change in the recognition properties of CUP2. This variant protein interacts with only one part of the wild-type site and prefers to bind to a different half-site from the wild-type protein. Although the variant has about 10% of wild-type DNA-binding activity, it appears to be completely incapable of activating transcription.

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Structure and Dynamics of the Glucocorticoid Receptor DNA-Binding Domain: Comparison of Wild Type and a Mutant with Altered Specificity†

Biochemistry ◽

10.1021/bi970343i ◽

1997 ◽

Vol 36 (37) ◽

pp. 11188-11197 ◽

Cited By ~ 12

Author(s):

Helena Berglund ◽

Magnus Wolf-Watz ◽

Thomas Lundbäck ◽

Susanne van den Berg ◽

Torleif Härd

Keyword(s):

Dna Binding ◽

Glucocorticoid Receptor ◽

Binding Domain ◽

Dna Binding Domain ◽

Wild Type ◽

Structure And Dynamics

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Identification of a minimal transforming domain of p53: negative dominance through abrogation of sequence-specific DNA binding.

Molecular and Cellular Biology ◽

10.1128/mcb.12.12.5581 ◽

1992 ◽

Vol 12 (12) ◽

pp. 5581-5592 ◽

Cited By ~ 224

Author(s):

E Shaulian ◽

A Zauberman ◽

D Ginsberg ◽

M Oren

Keyword(s):

Dna Binding ◽

Point Mutation ◽

P53 Gene ◽

Dominant Negative ◽

Mutant P53 ◽

Wild Type ◽

Transforming Activity ◽

Wild Type P53 ◽

Negative Dominance

Mutations in the p53 gene are most frequent in cancer. Many p53 mutants possess transforming activity in vitro. In cells transformed by such mutants, the mutant protein is oligomerized with endogenous cell p53. To determine the relevance of oligomerization for transformation, miniproteins containing C-terminal portions of p53 were generated. These miniproteins, although carrying no point mutation, transformed at least as efficiently as full-length mutant p53. Transforming activity was coupled with the ability to oligomerize with wild-type p53, as well as with the ability to abrogate sequence-specific DNA binding by coexpressed wild-type p53. These findings suggest that p53-mediated transformation may operate through a dominant negative mechanism, involving the generation of DNA binding-incompetent oligomers.

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Discovery of Small-Molecule Inhibitors Selectively Targeting the DNA-Binding Domain of the Human Androgen Receptor

Journal of Medicinal Chemistry ◽

10.1021/jm500802j ◽

2014 ◽

Vol 57 (15) ◽

pp. 6458-6467 ◽

Cited By ~ 51

Author(s):

Huifang Li ◽

Fuqiang Ban ◽

Kush Dalal ◽

Eric Leblanc ◽

Kate Frewin ◽

...

Keyword(s):

Androgen Receptor ◽

Dna Binding ◽

Small Molecule ◽

Small Molecule Inhibitors ◽

Binding Domain ◽

Dna Binding Domain ◽

Human Androgen Receptor

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Dissection of a carboxy-terminal region of the yeast regulatory protein RAP1 with effects on both transcriptional activation and silencing.

Molecular and Cellular Biology ◽

10.1128/mcb.12.3.1209 ◽

1992 ◽

Vol 12 (3) ◽

pp. 1209-1217 ◽

Cited By ~ 49

Author(s):

C F Hardy ◽

D Balderes ◽

D Shore

Keyword(s):

Dna Binding ◽

Binding Site ◽

Transcriptional Activation ◽

Binding Sites ◽

Binding Protein ◽

Binding Domain ◽

Dominant Negative Effect ◽

Dna Binding Domain ◽

Wild Type ◽

Carboxy Terminal

RAP1 is an essential sequence-specific DNA-binding protein in Saccharomyces cerevisiae whose binding sites are found in a large number of promoters, where they function as upstream activation sites, and at the silencer elements of the HMR and HML mating-type loci, where they are important for repression. We have examined the involvement of specific regions of the RAP1 protein in both repression and activation of transcription by studying the properties of a series of hybrid proteins containing RAP1 sequences fused to the DNA-binding domain of the yeast protein GAL4 (amino acids 1 to 147). GAL4 DNA-binding domain/RAP1 hybrids containing only the carboxy-terminal third of the RAP1 protein (which lacks the RAP1 DNA-binding domain) function as transcriptional activators of a reporter gene containing upstream GAL4 binding sites. Expression of some hybrids from the strong ADH1 promoter on multicopy plasmids has a dominant negative effect on silencers, leading to either partial or complete derepression of normally silenced genes. The GAL4/RAP1 hybrids have different effects on wild-type and several mutated but functional silencers. Silencers lacking either an autonomously replicating sequence consensus element or the RAP1 binding site are strongly derepressed, whereas the wild-type silencer or a silencer containing a deletion of the binding site for another silencer-binding protein, ABF1, are only weakly affected by hybrid expression. By examining a series of GAL4 DNA-binding domain/RAP1 hybrids, we have mapped the transcriptional activation and derepression functions to specific parts of the RAP1 carboxy terminus.(ABSTRACT TRUNCATED AT 250 WORDS)

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