Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
46
pubmed:dateCreated
2000-12-29
pubmed:abstractText
G-protein-gated inwardly rectifying K(+) (GIRK) channels are widely expressed in the brain and are activated by at least eight different neurotransmitters. As K(+) channels, they drive the transmembrane potential toward E(K) when open and thus dampen neuronal excitability. There are four mammalian GIRK subunits (GIRK1-4 or Kir 3.1-4), with GIRK1 being the most unique of the four by possessing a long carboxyl-terminal tail. Early studies suggested that GIRK1 was an integral component of native GIRK channels. However, more recent data indicate that native channels can be either homo- or heterotetrameric complexes composed of several GIRK subunit combinations. The functional implications of subunit composition are poorly understood at present. The purpose of this study was to examine the functional and biochemical properties of GIRK channels formed by the co-assembly of GIRK2 and GIRK3, the most abundant GIRK subunits found in the mammalian brain. To examine the properties of a channel composed of these two subunits, we co-transfected GIRK2 and GIRK3 in CHO-K1 cells and assayed the cells for channel activity by patch clamp. The most significant difference between the putative GIRK2/GIRK3 heteromultimeric channel and GIRK1/GIRKx channels at the single channel level was an approximately 5-fold lower sensitivity to activation by Gbetagamma. Complexes containing only GIRK2 and GIRK3 could be immunoprecipitated from transfected cells and could be purified from native brain tissue. These data indicate that functional GIRK channels composed of GIRK2 and GIRK3 subunits exist in brain.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
17
pubmed:volume
275
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
36211-6
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed-meshheading:10956667-Animals, pubmed-meshheading:10956667-Brain, pubmed-meshheading:10956667-CHO Cells, pubmed-meshheading:10956667-Cricetinae, pubmed-meshheading:10956667-Dose-Response Relationship, Drug, pubmed-meshheading:10956667-G Protein-Coupled Inwardly-Rectifying Potassium Channels, pubmed-meshheading:10956667-Heterotrimeric GTP-Binding Proteins, pubmed-meshheading:10956667-Ion Channel Gating, pubmed-meshheading:10956667-Macromolecular Substances, pubmed-meshheading:10956667-Mice, pubmed-meshheading:10956667-Mice, Knockout, pubmed-meshheading:10956667-Patch-Clamp Techniques, pubmed-meshheading:10956667-Potassium Channels, pubmed-meshheading:10956667-Potassium Channels, Inwardly Rectifying, pubmed-meshheading:10956667-Precipitin Tests, pubmed-meshheading:10956667-Protein Binding, pubmed-meshheading:10956667-Protein Structure, Quaternary, pubmed-meshheading:10956667-Protein Subunits, pubmed-meshheading:10956667-Transfection
pubmed:year
2000
pubmed:articleTitle
Functional and biochemical evidence for G-protein-gated inwardly rectifying K+ (GIRK) channels composed of GIRK2 and GIRK3.
pubmed:affiliation
Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Foundation, Rochester, Minnesota 55905, USA.
pubmed:publicationType
Journal Article