Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
14
pubmed:dateCreated
2002-4-1
pubmed:abstractText
In this study, we investigated the role of Ras and the mitogen-activated protein kinase (MAPK) pathway in the modulation of the inward rectifier potassium channel IRK1. We show that although expression of IRK1 in HEK 293 cells leads to the appearance of a potassium current with strong inward rectifying properties, coexpression of the constitutively active form of Ras (Ras-L61) results in a significant reduction of the mean current density without altering the biophysical properties of the channel. The inhibitory effect of Ras-L61 is not due to a decreased expression of IRK1 since Northern analysis indicates that IRK1 mRNA level is not affected by Ras-L61 co-expression. Moreover, the inhibition can be relieved by treatment with the mitogen-activated protein kinase/ERK kinase (MEK) inhibitor PD98059. Confocal microscopy analysis of cells transfected with the fusion construct green fluorescent protein-IRK1 shows that the channel is mainly localized at the plasma membrane. Coexpression of Ras-L61 delocalizes fluorescence to the cytoplasm, whereas treatment with PD98059 partially restores the membrane localization. In conclusion, our data indicate that the Ras-MAPK pathway modulates IRK1 current by affecting the subcellular localization of the channel. This suggests a role for Ras signaling in regulating the intracellular trafficking of this channel.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
5
pubmed:volume
277
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
12158-63
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:11809752-3T3 Cells, pubmed-meshheading:11809752-Animals, pubmed-meshheading:11809752-Biotinylation, pubmed-meshheading:11809752-Blotting, Northern, pubmed-meshheading:11809752-Blotting, Western, pubmed-meshheading:11809752-Cell Line, pubmed-meshheading:11809752-Cell Membrane, pubmed-meshheading:11809752-Cytoplasm, pubmed-meshheading:11809752-Electrophysiology, pubmed-meshheading:11809752-Enzyme Inhibitors, pubmed-meshheading:11809752-Flavonoids, pubmed-meshheading:11809752-Green Fluorescent Proteins, pubmed-meshheading:11809752-Humans, pubmed-meshheading:11809752-Luminescent Proteins, pubmed-meshheading:11809752-MAP Kinase Signaling System, pubmed-meshheading:11809752-Mice, pubmed-meshheading:11809752-Microscopy, Confocal, pubmed-meshheading:11809752-Potassium, pubmed-meshheading:11809752-Potassium Channels, pubmed-meshheading:11809752-Potassium Channels, Inwardly Rectifying, pubmed-meshheading:11809752-RNA, Messenger, pubmed-meshheading:11809752-Recombinant Fusion Proteins, pubmed-meshheading:11809752-Transfection, pubmed-meshheading:11809752-ras Proteins
pubmed:year
2002
pubmed:articleTitle
Modulation of the inward rectifier potassium channel IRK1 by the Ras signaling pathway.
pubmed:affiliation
Department of Structural and Functional Biology, Università dell'Insubria, Via J. H. Dunant 3, 21100 Varese, Italy.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't