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Updated: Jun 25, 2026

A High-throughput-compatible FRET-based Platform for Identification and Characterization of Botulinum Neurotoxin Light Chain Modulators
Published on: December 27, 2013
Binding of long-chain alpha-neurotoxin would stabilize the resting state of nAChR: a comparative study with
Adak Nasiripourdori1, Bijan Ranjbar, Hossein Naderi-Manesh
1Department of Biophysics, Faculty of Science, Tarbiat Modares University, P,O, Box 14115-175, Tehran, Iran. nasiripour@modares.ac.ir
Background:
The details of interaction in a complex between potent antagonists such as long chain alpha-neurotoxins and alpha-conotoxins with nicotinic acetylcholine receptor (nAChR), and conformational changes induced by these antagonists, are not yet clear. MODELING: In order to uncover some of these critical structural features, we conducted a docking simulation and a molecular dynamics simulation (MD) of a model of the ligand binding domain of nAChR in complex with a long-chain alpha-neurotoxin and an alpha-conotoxin.
Results:
Our docking results confirm the claim that T.nAChR is in the basal or resting state, which favors binding to the alpha-neurotoxins. Moreover, more correct "hits" for the alpha/gamma interface upon docking for conotoxin-nAChR confirm the preference of conotoxin GI for the alpha/gamma interface. More importantly, upon binding of alpha-neurotoxin, ligand-bonded nAChR is less dynamic in certain domains than the apo form of the conotoxin-AChR complex. Some critical interactions in the binding site such as the salt bridge formed between K145/D200 in the neurotoxin-nAChR complex is further stabilized during the MD simulation, while it is obviously more labile in the apo form.
Conclusion:
These observations could support the claim that alpha neurotoxins stabilize the nAChR resting state.
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