glycine-gated chloride channel complex
Definition
Target type: cellularcomponent
A protein complex that forms a transmembrane channel through which chloride ions may pass in response to glycine binding to the channel complex or one of its constituent parts. [GOC:mah]
The glycine-gated chloride channel complex is a transmembrane protein complex that mediates the passage of chloride ions across the plasma membrane of neurons and glial cells. It is composed of five subunits, each of which contains four transmembrane domains (M1-M4) and a large extracellular domain. The subunits assemble into a pentameric structure, forming a central pore through which chloride ions can pass. The complex is localized to the postsynaptic membrane of inhibitory synapses, where it plays a crucial role in synaptic transmission.
The extracellular domain of each subunit contains a glycine-binding site, which is responsible for the binding of the neurotransmitter glycine. Glycine binding to the receptor triggers a conformational change in the complex, leading to the opening of the chloride ion pore. The influx of chloride ions into the postsynaptic neuron hyperpolarizes the membrane, making it less likely to fire an action potential. This inhibitory effect is essential for regulating neuronal activity and maintaining normal brain function.
The cytoplasmic domain of each subunit contains a number of phosphorylation sites that are involved in regulating channel activity. Phosphorylation of these sites can affect the channel's sensitivity to glycine, its rate of desensitization, and its overall conductance.
The glycine-gated chloride channel complex is a target for a number of drugs and toxins. For example, the drug strychnine is a potent antagonist of the receptor, blocking the binding of glycine and preventing channel activation. This can lead to muscle spasms and convulsions. Other drugs, such as bicuculline and picrotoxin, also block the channel and can have similar effects.
The glycine-gated chloride channel complex is a highly conserved protein complex that is found in a wide variety of organisms. Mutations in the genes encoding the subunits of the complex can lead to a number of neurological disorders, including epilepsy, autism, and schizophrenia. The complex is also thought to play a role in a number of other neurological conditions, such as anxiety, depression, and addiction.
In summary, the glycine-gated chloride channel complex is a complex and important protein complex that plays a crucial role in inhibitory neurotransmission. It is a target for a number of drugs and toxins, and mutations in the genes encoding the subunits of the complex can lead to a number of neurological disorders.'
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Proteins (1)
| Protein | Definition | Taxonomy |
|---|---|---|
| Glycine receptor subunit beta | A glycine receptor subunit beta that is encoded in the genome of human. [PRO:DNx, UniProtKB:P48167] | Homo sapiens (human) |
Compounds (1)
| Compound | Definition | Classes | Roles |
|---|---|---|---|
| strychnine | strychnine : A monoterpenoid indole alkaloid that is strychnidine bearing a keto substituent at the 10-position. Strychnine: An alkaloid found in the seeds of STRYCHNOS NUX-VOMICA. It is a competitive antagonist at glycine receptors and thus a convulsant. It has been used as an analeptic, in the treatment of nonketotic hyperglycinemia and sleep apnea, and as a rat poison. | monoterpenoid indole alkaloid; organic heteroheptacyclic compound | avicide; cholinergic antagonist; glycine receptor antagonist; neurotransmitter agent; rodenticide |