Probing the interaction of the p53 C-terminal domain to the histone demethylase LSD1

Arch Biochem Biophys. 2017 Oct 15:632:202-208. doi: 10.1016/j.abb.2017.07.021. Epub 2017 Aug 4.

Abstract

The p53 transcription factor plays a central role in the regulation of the expression of several genes, and itself is post-translationally regulated through its different domains. Of particular relevance for p53 function is its intrinsically disordered C-terminal domain (CTD), representing a hotspot for post-translational modifications and a docking site for transcriptional regulators. For example, the histone H3 lysine demethylase 1 (LSD1) interacts with p53 via the p53-CTD for mutual regulation. To biochemically and functionally characterize this complex, we evaluated the in vitro interactions of LSD1 with several p53-CTD peptides differing in length and modifications. Binding was demonstrated through thermal shift, enzymatic and fluorescence polarization assays, but no enzymatic activity could be detected on methylated p53-CTD peptides in vitro. These experiments were performed using the wild-type enzyme and LSD1 variants that are mutated on three active-site residues. We found that LSD1 demethylase activity is inhibited by p53-CTD. We also noted that the association between the two proteins is mediated by mostly non-specific electrostatic interactions involving conserved active-site residues of LSD1 and a highly charged segment of the p53-CTD. We conclude that p53-CTD inhibits LSD1 activity and that the direct association between the two proteins can contribute to their functional cross-talk.

Keywords: Electrostatic interactions; Histone demethylase; Post-translational modification; Protein-protein interaction; Substrate specificity; p53.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Catalytic Domain
  • Histone Demethylases / chemistry*
  • Histone Demethylases / genetics
  • Histone Demethylases / metabolism
  • Humans
  • Methylation
  • Mutation
  • Peptides / chemistry*
  • Peptides / genetics
  • Peptides / metabolism
  • Protein Domains
  • Static Electricity
  • Tumor Suppressor Protein p53 / chemistry*
  • Tumor Suppressor Protein p53 / genetics
  • Tumor Suppressor Protein p53 / metabolism

Substances

  • Peptides
  • TP53 protein, human
  • Tumor Suppressor Protein p53
  • Histone Demethylases
  • KDM1A protein, human