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Molecular Analysis of Endothelial-mesenchymal Transition Induced by Transforming Growth Factor-β Signaling
07:49

Molecular Analysis of Endothelial-mesenchymal Transition Induced by Transforming Growth Factor-β Signaling

Published on: August 3, 2018

Mechanism of activation of the TGF-beta receptor

J L Wrana1, L Attisano, R Wieser

  • 1Howard Hughes Medical Institute, Memorial Sloan-Kettering Cancer Center, New York, New York 10021.

Nature
|August 4, 1994
PubMed

Insights

Transforming growth factor-beta (TGF-beta) directly binds receptor II, initiating a signaling cascade. Receptor II then phosphorylates receptor I, enabling downstream signal propagation.

Area of Science:

  • Cellular signaling pathways
  • Molecular biology
  • Biochemistry

Background:

  • Transforming growth factor-beta (TGF-beta) is a crucial cytokine involved in various cellular processes.
  • TGF-beta signaling is mediated by a complex of two transmembrane serine/threonine kinase receptors, Receptor I and Receptor II.
  • The precise roles of these receptors in initiating the TGF-beta signaling cascade were not fully elucidated.

Purpose of the Study:

  • To determine the specific roles of TGF-beta Receptor I and Receptor II in the TGF-beta signaling pathway.
  • To elucidate the initial molecular events following TGF-beta binding.

Main Methods:

  • The study involved analyzing the interaction between TGF-beta, Receptor I, and Receptor II.
  • Investigated the kinase activity of Receptor II and its effect on Receptor I phosphorylation.

Main Results:

  • TGF-beta directly binds to the constitutively active kinase, Receptor II.
  • TGF-beta binding to Receptor II facilitates the recruitment and subsequent phosphorylation of Receptor I.
  • Phosphorylated Receptor I initiates the downstream signaling cascade.

Conclusions:

  • The interaction between TGF-beta, Receptor II, and Receptor I defines the initial step in TGF-beta signal transduction.
  • This mechanism explains how a cytokine binding event translates into the first intracellular signaling event.

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