Source:http://linkedlifedata.com/resource/pubmed/id/15857907
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| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
3
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| pubmed:dateCreated |
2005-8-15
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| pubmed:abstractText |
G protein-gated inward rectifier (Kir3) channels are inhibited by activation of G(q/11)-coupled receptors and this has been postulated to involve the signaling molecules protein kinase C (PKC) and/or phosphatidylinositol 4,5-bisphosphate (PIP(2)). Their precise roles in mediating the inhibition of this family of channels remain controversial. We examine here their relative roles in causing inhibition of Kir3.1/3.2 channels stably expressed in human embryonic kidney (HEK)-293 cells after muscarinic M(3) receptor activation. In perforated patch mode, staurosporine prevented the G(q/11)-mediated, M(3) receptor, inhibition of channel activity. Recovery from M(3)-mediated inhibition was wortmannin sensitive. Whole cell currents, where the patch pipette was supplemented with PIP(2), were still irreversibly inhibited by M(3) receptor stimulation. When adenosine A(1) receptors were co-expressed, inclusion of PIP(2) rescued the A(1)-mediated response. Recordings from inside-out patches showed that catalytically active PKC applied directly to the intracellular membrane face inhibited the channels: a reversible effect modulated by okadaic acid. Generation of mutant heteromeric channel Kir3.1S185A/Kir3.2C-S178A, still left the channel susceptible to receptor, pharmacological, and direct kinase-mediated inhibition. Biochemically, labeled phosphate is incorporated into the channel. We suggest that PKC-delta mediates channel inhibition because recombinant PKC-delta inhibited channel activity, M(3)-mediated inhibition of the channel, was counteracted by overexpression of two types of dominant negative PKC-delta constructs, and, by using confocal microscopy, we have demonstrated translocation of green fluorescent protein-tagged PKC-delta to the plasma membrane on M(3) receptor stimulation. Thus Kir3.1/3.2 channels are sensitive to changes in membrane phospholipid levels but this is contingent on the activity of PKC-delta after M(3) receptor activation in HEK-293 cells.
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| pubmed:grant | |
| pubmed:commentsCorrections | |
| pubmed:language |
eng
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| pubmed:journal | |
| pubmed:citationSubset |
IM
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| pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/G Protein-Coupled...,
http://linkedlifedata.com/resource/pubmed/chemical/GTP-Binding Protein alpha...,
http://linkedlifedata.com/resource/pubmed/chemical/KCNJ3 protein, human,
http://linkedlifedata.com/resource/pubmed/chemical/PRKCD protein, human,
http://linkedlifedata.com/resource/pubmed/chemical/PRKCE protein, human,
http://linkedlifedata.com/resource/pubmed/chemical/Phosphatidylinositol 4,5-Diphosphate,
http://linkedlifedata.com/resource/pubmed/chemical/Potassium Channels, Inwardly...,
http://linkedlifedata.com/resource/pubmed/chemical/Protein Kinase C,
http://linkedlifedata.com/resource/pubmed/chemical/Protein Kinase C-delta,
http://linkedlifedata.com/resource/pubmed/chemical/Protein Kinase C-epsilon,
http://linkedlifedata.com/resource/pubmed/chemical/Receptor, Muscarinic M3
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| pubmed:status |
MEDLINE
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| pubmed:month |
Sep
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| pubmed:issn |
0363-6143
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| pubmed:author | |
| pubmed:issnType |
Print
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| pubmed:volume |
289
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| pubmed:owner |
NLM
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| pubmed:authorsComplete |
Y
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| pubmed:pagination |
C543-56
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| pubmed:dateRevised |
2009-11-19
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| pubmed:meshHeading |
pubmed-meshheading:15857907-Cell Line,
pubmed-meshheading:15857907-Cell Membrane,
pubmed-meshheading:15857907-G Protein-Coupled Inwardly-Rectifying Potassium Channels,
pubmed-meshheading:15857907-GTP-Binding Protein alpha Subunits, Gq-G11,
pubmed-meshheading:15857907-Humans,
pubmed-meshheading:15857907-Kidney,
pubmed-meshheading:15857907-Membrane Potentials,
pubmed-meshheading:15857907-Patch-Clamp Techniques,
pubmed-meshheading:15857907-Phosphatidylinositol 4,5-Diphosphate,
pubmed-meshheading:15857907-Phosphorylation,
pubmed-meshheading:15857907-Potassium Channels, Inwardly Rectifying,
pubmed-meshheading:15857907-Protein Kinase C,
pubmed-meshheading:15857907-Protein Kinase C-delta,
pubmed-meshheading:15857907-Protein Kinase C-epsilon,
pubmed-meshheading:15857907-Receptor, Muscarinic M3,
pubmed-meshheading:15857907-Receptor Cross-Talk
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| pubmed:year |
2005
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| pubmed:articleTitle |
PKC-delta sensitizes Kir3.1/3.2 channels to changes in membrane phospholipid levels after M3 receptor activation in HEK-293 cells.
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| pubmed:affiliation |
Dept. of Medicine, University College of London, London WC1E 6JJ, UK. sean.brown@ucl.ac.uk
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| pubmed:publicationType |
Journal Article,
Research Support, Non-U.S. Gov't
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