Computational study of the transmembrane domain of the acetylcholine receptor

European Biophysics Journal - Tập 38 - Trang 961-970 - 2009
Chen Song1, Ben Corry1
1School of Biomedical, Biomolecular and Chemical Sciences, The University of Western Australia, Crawley, Australia

Tóm tắt

The nicotinic acetylcholine receptor (nAChR) is a ligand-gated ion channel protein whose transmembrane domain (TM-domain) is believed to be responsible for channel gating via a hydrophobic effect. In this work, we perform molecular dynamics and Brownian dynamics simulations to investigate the effect of transmembrane potential on the conformation and water occupancy of TM-domain, and the resulting ion permeation events. The results show that the behavior of the hydrophobic gate is voltage-dependent. Large hyperpolarized membrane potential can change the conformation of TM-domain and water occupancy in this region, which may enable ion conduction. An electrostatic gating mechanism is also proposed from our simulations, which seems to play a role in addition to the well-known hydrophobic effect.

Tài liệu tham khảo

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