FOXO4 interacts with p53 TAD and CRD and inhibits its binding to DNA

Protein Sci. 2022 May;31(5):e4287. doi: 10.1002/pro.4287.


Transcription factor p53 protects cells against tumorigenesis when subjected to various cellular stresses. Under these conditions, p53 interacts with transcription factor Forkhead box O (FOXO) 4, thereby inducing cellular senescence by upregulating the transcription of senescence-associated protein p21. However, the structural details of this interaction remain unclear. Here, we characterize the interaction between p53 and FOXO4 by NMR, chemical cross-linking, and analytical ultracentrifugation. Our results reveal that the interaction between p53 TAD and the FOXO4 Forkhead domain is essential for the overall stability of the p53:FOXO4 complex. Furthermore, contacts involving the N-terminal segment of FOXO4, the C-terminal negative regulatory domain of p53 and the DNA-binding domains of both proteins stabilize the complex, whose formation blocks p53 binding to DNA but without affecting the DNA-binding properties of FOXO4. Therefore, our structural findings may help to understand the intertwined functions of p53 and FOXO4 in cellular homeostasis, longevity, and stress response.

Keywords: DNA binding; Forkhead box O 4; nuclear magnetic resonance; protein-protein interaction; senescence; transcription factor p53.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Cycle Proteins / metabolism
  • DNA / chemistry
  • Forkhead Transcription Factors* / chemistry
  • Forkhead Transcription Factors* / genetics
  • Forkhead Transcription Factors* / metabolism
  • Protein Binding
  • Tumor Suppressor Protein p53* / genetics
  • Tumor Suppressor Protein p53* / metabolism


  • Cell Cycle Proteins
  • Forkhead Transcription Factors
  • Tumor Suppressor Protein p53
  • DNA