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Suppression of p53 response by blocking p53-Mediator binding with a stapled peptide

ABSTRACT: DNA-binding transcription factors (TFs) have been challenging to target with molecular probes. Many TFs function in part through interaction with Mediator; we sought to block p53 function by disrupting the p53-Mediator interaction. Through rational design and activity-based screening, we characterized a stapled peptide, with functional mimics of both p53 activation domains, that selectively disrupted p53- and Mediator-dependent transcription in vitro. This “bivalent peptide” also suppressed p53 transcriptional response in human cancer cells. Our strategy circumvents the TF and instead targets the TF-Mediator interface, with desired transcriptional outcomes. Different TFs target Mediator through different subunits, suggesting this strategy could be generalizable.

ORGANISM(S): Homo sapiens

PROVIDER: GSE193418 | GEO | 2022/04/05

REPOSITORIES: GEO

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Suppression of p53 response by blocking p53–Mediator binding with a stapled peptide

Project description:DNA-binding transcription factors (TFs) have been challenging to target with molecular probes. Many TFs function in part through interaction with Mediator; we sought to block p53 function by disrupting the p53-Mediator interaction. Through rational design and activity-based screening, we characterized a stapled peptide, with functional mimics of both p53 activation domains, that selectively disrupted p53- and Mediator-dependent transcription in vitro. This “bivalent peptide” also suppressed p53 transcriptional response in human cancer cells. Our strategy circumvents the TF and instead targets the TF-Mediator interface, with desired transcriptional outcomes. Different TFs target Mediator through different subunits, suggesting this strategy could be generalizable.

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