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Updated: Jul 6, 2026
09:16
Oligopeptide Competition Assay for Phosphorylation Site Determination
Published on: May 18, 2017
Allovalency revisited: an analysis of multisite phosphorylation and substrate rebinding
1Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA. locasale@mit.edu
The Journal of Chemical Physics
|March 26, 2008
Summary
Ligand rebinding to multiple phosphorylation sites can alter cell signaling dose responses nonlinearly. However, rebinding alone does not generate high biological cooperation.
Area of Science:
- Cellular biology
- Biophysics
- Biochemistry
Background:
- Multiple phosphorylation sites are common in cell signaling pathways.
- Ligand rebinding after dissociation from a receptor is a known phenomenon.
Purpose of the Study:
- To investigate the impact of multiple, equivalent binding sites on biological responses.
- To understand how ligand rebinding influences cell signaling systems.
Main Methods:
- Utilized a self-consistent integral equation formalism for ligand rebinding.
- Employed Monte Carlo simulations to model the system.
Main Results:
- Predicted multiple physical regimes based on rebinding prevalence.
- Showed that significant ligand rebinding can nonlinearly affect dose-response curves.
- Demonstrated that ligand rebinding alone is insufficient for high biological cooperation.
Conclusions:
- Ligand rebinding to multiple phosphorylation sites introduces complex nonlinearities in dose-response relationships.
- While influencing binding curves, rebinding alone does not appear to be the sole driver of highly cooperative biological responses.
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