Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
31
pubmed:dateCreated
2003-7-28
pubmed:abstractText
G protein-activated K+ channels (Kir3 or GIRK) are activated by direct binding of Gbetagamma. The binding sites of Gbetagamma in the ubiquitous GIRK1 (Kir3.1) subunit have not been unequivocally charted, and in the neuronal GIRK2 (Kir3.2) subunit the binding of Gbetagamma has not been studied. We verified and extended the map of Gbetagamma-binding sites in GIRK1 by using two approaches: direct binding of Gbetagamma to fragments of GIRK subunits (pull down), and competition of these fragments with the Galphai1 subunit for binding to Gbetagamma. We also mapped the Gbetagamma-binding sites in GIRK2. In both subunits, the N terminus binds Gbetagamma. In the C terminus, the Gbetagamma-binding sites in the two subunits are not identical; GIRK1, but not GIRK2, has a previously unrecognized Gbetagamma-interacting segments in the first half of the C terminus. The main C-terminal Gbetagamma-binding segment found in both subunits is located approximately between amino acids 320 and 409 (by GIRK1 count). Mutation of C-terminal leucines 262 or 333 in GIRK1, recognized previously as crucial for Gbetagamma regulation of the channel, and of the corresponding leucines 273 and 344 in GIRK2 dramatically altered the properties of K+ currents via GIRK1/GIRK2 channels expressed in Xenopus oocytes but did not appreciably reduce the binding of Gbetagamma to the corresponding fusion proteins, indicating that these residues are mainly important for the regulation of Gbetagamma-induced changes in channel gating rather than Gbetagamma binding.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/G Protein-Coupled..., http://linkedlifedata.com/resource/pubmed/chemical/G-protein Beta gamma, http://linkedlifedata.com/resource/pubmed/chemical/GTP-Binding Protein beta Subunits, http://linkedlifedata.com/resource/pubmed/chemical/GTP-Binding Protein gamma Subunits, http://linkedlifedata.com/resource/pubmed/chemical/Glutathione Transferase, http://linkedlifedata.com/resource/pubmed/chemical/Heterotrimeric GTP-Binding Proteins, http://linkedlifedata.com/resource/pubmed/chemical/KCNJ3 protein, human, http://linkedlifedata.com/resource/pubmed/chemical/Peptide Fragments, http://linkedlifedata.com/resource/pubmed/chemical/Potassium Channels, http://linkedlifedata.com/resource/pubmed/chemical/Potassium Channels, Inwardly..., http://linkedlifedata.com/resource/pubmed/chemical/Protein Subunits, http://linkedlifedata.com/resource/pubmed/chemical/Recombinant Fusion Proteins
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
278
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
29174-83
pubmed:dateRevised
2010-6-22
pubmed:meshHeading
pubmed-meshheading:12743112-Amino Acid Sequence, pubmed-meshheading:12743112-Animals, pubmed-meshheading:12743112-Binding Sites, pubmed-meshheading:12743112-Cell Membrane, pubmed-meshheading:12743112-Electric Conductivity, pubmed-meshheading:12743112-Female, pubmed-meshheading:12743112-G Protein-Coupled Inwardly-Rectifying Potassium Channels, pubmed-meshheading:12743112-GTP-Binding Protein beta Subunits, pubmed-meshheading:12743112-GTP-Binding Protein gamma Subunits, pubmed-meshheading:12743112-Gene Expression, pubmed-meshheading:12743112-Glutathione Transferase, pubmed-meshheading:12743112-Heterotrimeric GTP-Binding Proteins, pubmed-meshheading:12743112-Ion Channel Gating, pubmed-meshheading:12743112-Mice, pubmed-meshheading:12743112-Molecular Sequence Data, pubmed-meshheading:12743112-Mutagenesis, pubmed-meshheading:12743112-Oocytes, pubmed-meshheading:12743112-Peptide Fragments, pubmed-meshheading:12743112-Potassium Channels, pubmed-meshheading:12743112-Potassium Channels, Inwardly Rectifying, pubmed-meshheading:12743112-Protein Subunits, pubmed-meshheading:12743112-Rats, pubmed-meshheading:12743112-Recombinant Fusion Proteins, pubmed-meshheading:12743112-Structure-Activity Relationship, pubmed-meshheading:12743112-Transfection, pubmed-meshheading:12743112-Xenopus
pubmed:year
2003
pubmed:articleTitle
Mapping the Gbetagamma-binding sites in GIRK1 and GIRK2 subunits of the G protein-activated K+ channel.
pubmed:affiliation
Department of Physiology and Pharmacology, Sackler School of Medicine, Tel Aviv University, Ramat Aviv 69978, Israel.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't