The F-box protein Ppa is a common regulator of core EMT factors Twist, Snail, Slug, and Sip1

J Cell Biol. 2011 Jul 11;194(1):17-25. doi: 10.1083/jcb.201012085. Epub 2011 Jul 4.


A small group of core transcription factors, including Twist, Snail, Slug, and Sip1, control epithelial-mesenchymal transitions (EMTs) during both embryonic development and tumor metastasis. However, little is known about how these factors are coordinately regulated to mediate the requisite behavioral and fate changes. It was recently shown that a key mechanism for regulating Snail proteins is by modulating their stability. In this paper, we report that the stability of Twist is also regulated by the ubiquitin-proteasome system. We found that the same E3 ubiquitin ligase known to regulate Snail family proteins, Partner of paired (Ppa), also controlled Twist stability and did so in a manner dependent on the Twist WR-rich domain. Surprisingly, Ppa could also target the third core EMT regulatory factor Sip1 for proteasomal degradation. Together, these results indicate that despite the structural diversity of the core transcriptional regulatory factors implicated in EMT, a common mechanism has evolved for controlling their stability and therefore their function.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Epithelial-Mesenchymal Transition*
  • F-Box Proteins / metabolism*
  • Homeodomain Proteins / metabolism*
  • Repressor Proteins / metabolism*
  • Snail Family Transcription Factors
  • Transcription Factors / metabolism*
  • Twist-Related Protein 1 / metabolism*
  • Xenopus Proteins / metabolism*
  • Xenopus laevis / metabolism*


  • F-Box Proteins
  • FBXL14 protein, Xenopus
  • Homeodomain Proteins
  • Repressor Proteins
  • Snail Family Transcription Factors
  • Transcription Factors
  • Twist-Related Protein 1
  • Xenopus Proteins
  • ZEB2 protein, Xenopus