Related Experiment Video

Updated: Sep 10, 2026

A Kinetic Fluorescence-based Ca2+ Mobilization Assay to Identify G Protein-coupled Receptor Agonists, Antagonists, and Allosteric Modulators
07:41

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Published on: February 20, 2018

TGF-beta receptors

P R Segarini1

  • 1Celtrix Laboratories, Collagen Corporation, Palo Alto, CA 94303.

Ciba Foundation Symposium
|January 1, 1991
PubMed

Insights

Transforming growth factor-beta (TGF-beta) binds to cell surface receptors with varying affinity. Research identifies TGF-beta receptor types and explores signal transduction pathways for TGF-beta-mediated cellular responses.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Biochemistry

Background:

  • Transforming growth factor-beta (TGF-beta) is a crucial signaling molecule involved in numerous cellular processes.
  • Cellular responses to TGF-beta are mediated by specific cell surface receptors.

Purpose of the Study:

  • To characterize the binding properties and types of TGF-beta receptors.
  • To investigate the signal transduction pathways involved in TGF-beta-induced cellular responses.

Main Methods:

  • Characterization of cell surface proteins that bind TGF-beta 1 and TGF-beta 2.
  • Classification of putative receptors based on molecular weight and properties.
  • Investigation of signal transduction pathways, including guanine nucleotide binding protein-dependent pathways.

Main Results:

  • TGF-beta exhibits high-affinity binding to most cell types, with dissociation constants ranging from 1 pM to 60 pM.
  • Two main types of TGF-beta receptors (Type I and Type II) were identified, with approximate molecular weights of 50,000 and 80,000, respectively.
  • A large membrane-bound proteoglycan (beta-glycan) binds TGF-beta but its function remains unknown and it is not associated with TGF-beta-mediated responses.
  • Multiple signal transduction pathways exist for TGF-beta, including at least one dependent on guanine nucleotide binding proteins.

Conclusions:

  • TGF-beta receptors are glycoproteins with distinct molecular weights, mediating TGF-beta responses.
  • Multiple pathways are involved in TGF-beta signal transduction, suggesting complex cellular regulation.
  • Further research on TGF-beta receptor purification and cloning is essential for understanding signal transmission mechanisms.

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