Regulation of TGF-β family signalling by ubiquitination and deubiquitination

Takeshi Imamura1, Yusuke Oshima, Atsuhiko Hikita

  • 1Department of Molecular Medicine for Pathogenesis, Ehime University Graduate School of Medicine; Division of Bio-imaging, Proteo-Science Center, Ehime University; Translational Research Center, Ehime University Hospital; and Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Shitsukawa, Toon, Ehime 791-0295, Japan.

Journal of Biochemistry
|October 30, 2013
PubMed

Insights

Ubiquitin modifications, including ubiquitination and deubiquitination, critically regulate transforming growth factor-β (TGF-β) signaling pathways. These modifications control TGF-β family signal transduction and crosstalk with other cellular pathways.

Area of Science:

  • Cellular Biology
  • Molecular Biology
  • Biochemistry

Background:

  • Transforming growth factor-β (TGF-β) family proteins regulate diverse cellular processes like proliferation, differentiation, migration, and apoptosis.
  • TGF-β signaling primarily involves serine/threonine kinase receptors and Smad proteins.
  • Post-translational modifications, particularly ubiquitination, are crucial for regulating TGF-β signaling.

Purpose of the Study:

  • To review the current understanding of how ubiquitin modifications regulate TGF-β family signaling.
  • To highlight the dual role of ubiquitin modifications in both positive and negative regulation of TGF-β pathways.
  • To explore the involvement of ubiquitination in the crosstalk between TGF-β signaling and other cellular pathways.

Main Methods:

  • Literature review of studies on ubiquitin modifications and TGF-β signaling.
  • Analysis of the roles of E3 ubiquitin ligases and deubiquitinating enzymes.
  • Examination of ubiquitination's impact on TGF-β receptors, Smad proteins, and associated factors.

Main Results:

  • E3 ubiquitin ligases mediate the degradation of TGF-β pathway components, affecting signaling.
  • Non-degradative ubiquitin modifications also play regulatory roles in TGF-β signaling.
  • Deubiquitination by specific enzymes fine-tunes TGF-β pathway activity.
  • Ubiquitination is essential for TGF-β signaling crosstalk with other pathways.

Conclusions:

  • Ubiquitin modifications are key regulators of TGF-β family signal transduction.
  • Both degradative and non-degradative ubiquitination, along with deubiquitination, are vital for controlling TGF-β signaling.
  • Ubiquitin modifications orchestrate complex cross-talk between TGF-β and other signaling networks.

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