Format

Send to

Choose Destination
Biophys J. 2010 Aug 4;99(3):L29-31. doi: 10.1016/j.bpj.2010.05.018.

Hill coefficients of a polymodal Monod-Wyman-Changeux model for ion channel gating.

Author information

1
Department of Physiology and Biophysical Sciences, State University of New York at Buffalo, Buffalo, New York, USA. qin@buffalo.edu

Abstract

Allosteric transitions of ion channels can be driven by multiple sources of free energies. One class of model for describing such transitions is the multistimulus Monod-Wyman-Changeux model, in which each stimulus interacts with a specific sensor on the protein and activation of the sensor is allosterically coupled to conformational changes of the protein. In general, when a protein is stressed by multiple stimuli, one stimulus can influence the response to another, which can result in both a shift of the midpoint of the dose-response curve and a change of the slope of the curve. Here I show that, for a Monod-Wyman-Changeux model with independent sensors, the different dose-response curves of open probability for one stimulus have the same slope at the same agonist concentration. In the other words, the slope of the dose-response curve for one stimulus is an intrinsic property of the sensors for that stimulus; it is independent of other stimuli or their sensor properties. As the dose-response curve for many receptors can be fit to a Boltzmann or Hill equation, this property provides a practical, usable test for applicability of such models.

PMID:
20682245
PMCID:
PMC2913192
DOI:
10.1016/j.bpj.2010.05.018
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Elsevier Science Icon for PubMed Central
Loading ...
Support Center