Inward rectifier K+ channel Kir2.3 is localized at the postsynaptic membrane of excitatory synapses.
Classical inwardly rectifying K+ channels (Kir2.0) are responsible for maintaining the resting membrane potential near the K+ equilibrium potential in various cells, including neurons. Although Kir2.3 is known to be expressed abundantly in the forebrain, its precise localization has not been identified. Using an antibody specific to Kir2.3, we examined ... the subcellular localization of Kir2.3 in mouse brain. Kir2.3 immunoreactivity was detected in a granular pattern in restricted areas of the brain, including the olfactory bulb (OB). Immunoelectron microscopy of the OB revealed that Kir2.3 immunoreactivity was specifically clustered on the postsynaptic membrane of asymmetric synapses between granule cells and mitral/tufted cells. The immunoprecipitants for Kir2.3 obtained from brain contained PSD-95 and chapsyn-110, PDZ domain-containing anchoring proteins. In vitro binding assay further revealed that the COOH-terminal end of Kir2.3 is responsible for the association with these anchoring proteins. Therefore, the Kir channel may be involved in formation of the resting membrane potential of the spines and, thus, would affect the response of N-methyl-D-aspartic acid receptor channels at the excitatory postsynaptic membrane.
Mesh Terms:
Adaptor Proteins, Signal Transducing, Animals, Antibody Specificity, Brain, Carrier Proteins, Cell Line, Guanylate Kinase, Humans, Immunohistochemistry, Intracellular Signaling Peptides and Proteins, Kidney, Membrane Proteins, Mice, Mice, Inbred BALB C, Microscopy, Immunoelectron, Nerve Tissue Proteins, Neurons, Neuropeptides, Nuclear Proteins, Nucleoside-Phosphate Kinase, Olfactory Bulb, Organ Specificity, Phosphoproteins, Potassium Channels, Potassium Channels, Inwardly Rectifying, Rats, Rats, Wistar, Synapses, Synaptic Membranes, Transcription Factors
Adaptor Proteins, Signal Transducing, Animals, Antibody Specificity, Brain, Carrier Proteins, Cell Line, Guanylate Kinase, Humans, Immunohistochemistry, Intracellular Signaling Peptides and Proteins, Kidney, Membrane Proteins, Mice, Mice, Inbred BALB C, Microscopy, Immunoelectron, Nerve Tissue Proteins, Neurons, Neuropeptides, Nuclear Proteins, Nucleoside-Phosphate Kinase, Olfactory Bulb, Organ Specificity, Phosphoproteins, Potassium Channels, Potassium Channels, Inwardly Rectifying, Rats, Rats, Wistar, Synapses, Synaptic Membranes, Transcription Factors
Am. J. Physiol., Cell Physiol.
Date: Jun. 01, 2002
PubMed ID: 11997254
View in: Pubmed Google Scholar
Download Curated Data For This Publication
3637
Switch View:
- Interactions 9