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Updated: Aug 11, 2026
14:28
Peptide-based Identification of Functional Motifs and their Binding Partners
Published on: July 1, 2013
Synthetic peptides bind to high-affinity thrombin receptors and modulate thrombin mitogenesis
K C Glenn1, G H Frost, J S Bergmann
1Monsanto Corporation.
Peptide Research
|November 1, 1988
Summary
Synthetic peptides reveal thrombin
Area of Science:
- Biochemistry
- Cell Biology
- Molecular Signaling
Background:
- Thrombin initiates cell proliferation through receptor binding and enzymatic activity.
- Understanding thrombin's role in cell signaling is crucial for deciphering mitogenic pathways.
Purpose of the Study:
- To identify specific regions of thrombin responsible for high-affinity receptor binding and mitogenic signal generation.
- To characterize the function of synthetic peptides representing thrombin domains in cell proliferation.
Main Methods:
- Utilized synthetic peptides derived from human prothrombin (p508-530) and RGDA (p517-520).
- Assessed 125I-alpha-thrombin binding inhibition and mitogenic effects in cell cultures.
- Investigated effects on DNA synthesis in the presence and absence of phorbol myristate acetate (PMA).
Main Results:
- Peptide p508-530 significantly inhibited thrombin binding and enhanced/stimulated DNA synthesis, indicating a high-affinity binding domain.
- Peptide RGDA competed for binding but inhibited mitogenesis, acting as an antagonist.
- Non-homologous peptides showed no effect on thrombin binding or mitogenesis.
Conclusions:
- A specific region (p508-530) of thrombin contains a high-affinity receptor binding domain crucial for mitogenic signaling.
- Synthetic peptides can act as either agonists or antagonists of thrombin-induced cell proliferation, depending on their structure and signaling capacity.
- These findings elucidate the molecular mechanisms underlying thrombin's role in cell proliferation and receptor interaction.
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