G protein-gated inwardly rectifying K+ (GIRK/Kir3) channels: Molecular, cellular, and subcellular diversity

G protein-gated inwardly rectifying K+ (GIRK/Kir3) channels are mainly expressed in excitable cells such as neurons and atrial myocytes, where they can respond to a wide variety of neurotransmitters. Four GIRK subunits have been found in mammals (GIRK1-4) and act as downstream targets for various Ga...

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Detalles Bibliográficos
Autores: Martín Belmonte, Alejandro, Aguado Rubio, Carolina, Alfaro Ruiz, Rocío, Luján Miras, Rafael
Tipo de recurso: artículo
Fecha de publicación:2025
País:España
Institución:Universidad de Castilla-La Mancha
Repositorio:RUIdeRA. Repositorio Institucional de la UCLM
OAI Identifier:oai:ruidera.uclm.es:10578/42854
Acceso en línea:https://www.hh.um.es/Abstracts/Vol_/_/__18822.htm
https://hdl.handle.net/10578/42854
Access Level:acceso abierto
Palabra clave:G protein-coupled receptors (GPCRs)
GIRK channels
Hyperpolarization
Immunoelectron microscopy
Immunohistochemistry
Inhibition
Macromolecular complexes
Neurological diseases
Neurons
Pathology
Pharmacological targets
Potassium efflux
Subcellular localization
Descripción
Sumario:G protein-gated inwardly rectifying K+ (GIRK/Kir3) channels are mainly expressed in excitable cells such as neurons and atrial myocytes, where they can respond to a wide variety of neurotransmitters. Four GIRK subunits have been found in mammals (GIRK1-4) and act as downstream targets for various Gai/o-linked G protein-coupled receptors (GPCRs). Activation of GIRK channels produces a postsynaptic efflux of potassium from the cell, responsible for hyperpolarization/inhibition of the neuron. A growing body of evidence suggests that dysregulation of GIRK signalling can lead to excessive or deficient neuronal excitability, which contributes to neurological diseases and disorders. Therefore, GIRK channels are proposed as new pharmacological targets. The function of GIRK channels in neurons is not only determined by their biophysical properties but also by their cellular and subcellular localization patterns and densities on the neuronal surface. GIRK channels can be located within several subcellular compartments, where they have many different functional implications. This subcellular localization changes dynamically along the neuronal surface in response to drug intake. Ongoing research is focusing on determining the proteins that form macromolecular complexes with GIRK channels and are responsible for fast and precise signalling under physiological conditions, and how their alteration is implicated in pathological conditions. In this review, the distinct regional, cellular, and subcellular distribution of GIRK channel subunits in the brain will be discussed in view of their possible functional and pathological implications.