Ligand‐Gated Ion Channels


Ligand‐gated ion channels (LGICs) form a diverse superfamily of cell‐surface neurotransmitter receptors that mediate rapid cell–cell signalling. They are multisubunit transmembrane proteins in which 3–5 subunits are arranged around a central ion channel pore. In addition to their role as receptors for neurotransmitters, LGICs have been implicated in several neurological disorders and are important target sites for drug therapy and drug development.

Keywords: ion channels; neurotransmitter receptors; receptors; signal transduction

Figure 1.

Ligand‐gated ion channel (LGIC) structure and subunit topology. LGICs can be subdivided into three structurally distinct subfamilies: (a) Cys‐loop LGICs, (b) Glutamate‐gated cation channels and (c) ATP‐gated ion channels. All are multisubunit transmembrane proteins in which 3–5 subunits are arranged around a central ion channel. Each subunit contains an extracellular ligand‐binding domain and 2–4 transmembrane hydrophobic domains. For some LGICs there remains some uncertainty about the number of subunits and the precise subunit topology, but the structures illustrated represent the current working model for these subfamilies of LGIC based on a variety of experimental evidence.



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Further Reading

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Millar, Neil S(Apr 2006) Ligand‐Gated Ion Channels. In: eLS. John Wiley & Sons Ltd, Chichester. [doi: 10.1038/npg.els.0000154]