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Predicate | Object |
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rdf:type | |
lifeskim:mentions |
umls-concept:C0007634,
umls-concept:C0013935,
umls-concept:C0017262,
umls-concept:C0022646,
umls-concept:C0086418,
umls-concept:C0332120,
umls-concept:C0596235,
umls-concept:C0812263,
umls-concept:C1171362,
umls-concept:C1421167,
umls-concept:C1421170,
umls-concept:C1515670,
umls-concept:C1550548,
umls-concept:C1555714,
umls-concept:C1705654
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pubmed:issue |
1
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pubmed:dateCreated |
1998-2-3
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pubmed:abstractText |
Ca2+ release from its internal stores as a result of activation of phospholipase C is accompanied by Ca2+ influx from the extracellular space. Ca2+ influx channels may be formed of proteins homologous to Drosophila Trp. At least six non-allelic Trp genes are present in the mouse genome. Full-length human, bovine, mouse, and rat cDNAs for Trp1, 3, 4, 6 have been cloned. Expression of these genes in various mammalian cells has provided evidence that Trp proteins form plasma membrane Ca2+-permeant channels that can be activated by an agonist that activates phospholipase C, by inositol 1,4, 5-trisphosphate, and/or store depletion. We have stably expressed human Trp3 (hTrp3) in human embryonic kidney (HEK)293 cells. Measurement of intracellular Ca2+ concentrations in Fura2-loaded cells showed that cell lines expressing hTrp3 have significantly higher basal and agonist-stimulated influxes of Ca2+, Mn2+, Ba2+, and Sr2+ than control cells. The increase in Ca2+ entry attributable to the expression of hTrp3 obtained upon store depletion by thapsigargin was much lower than that obtained by stimulation with agonists acting via a Gq-coupled receptor. Addition of agonists to thapsigargin-treated Trp3 cells resulted in a further increase in the entry of divalent cations. The increased cation entry in Trp3 cells was blocked by high concentrations of SKF 96365, verapamil, La3+, Ni2+, and Gd3+. The Trp3-mediated Ca2+ influx activated by agonists was inhibited by a phospholipase C inhibitor, U73122. We propose that expression of hTrp3 in these cells forms a non-selective cation channel that opens after the activation of phospholipase C but not after store depletion. In addition, a subpopulation of the expressed hTrp3 may form heteromultimeric channels with endogenous proteins that are sensitive to store depletion.
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pubmed:grant | |
pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Calcium,
http://linkedlifedata.com/resource/pubmed/chemical/Calcium Channels,
http://linkedlifedata.com/resource/pubmed/chemical/Cations, Divalent,
http://linkedlifedata.com/resource/pubmed/chemical/Epitopes,
http://linkedlifedata.com/resource/pubmed/chemical/ITPR1 protein, human,
http://linkedlifedata.com/resource/pubmed/chemical/Inositol 1,4,5-Trisphosphate,
http://linkedlifedata.com/resource/pubmed/chemical/Inositol 1,4,5-Trisphosphate...,
http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Cytoplasmic and Nuclear,
http://linkedlifedata.com/resource/pubmed/chemical/Type C Phospholipases
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pubmed:status |
MEDLINE
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pubmed:month |
Jan
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pubmed:issn |
0021-9258
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:day |
2
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pubmed:volume |
273
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
133-42
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pubmed:dateRevised |
2007-11-15
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pubmed:meshHeading |
pubmed-meshheading:9417057-Animals,
pubmed-meshheading:9417057-COS Cells,
pubmed-meshheading:9417057-Calcium,
pubmed-meshheading:9417057-Calcium Channels,
pubmed-meshheading:9417057-Cations, Divalent,
pubmed-meshheading:9417057-Cell Line,
pubmed-meshheading:9417057-Enzyme Activation,
pubmed-meshheading:9417057-Epitopes,
pubmed-meshheading:9417057-Glycosylation,
pubmed-meshheading:9417057-Humans,
pubmed-meshheading:9417057-Inositol 1,4,5-Trisphosphate,
pubmed-meshheading:9417057-Inositol 1,4,5-Trisphosphate Receptors,
pubmed-meshheading:9417057-Ion Transport,
pubmed-meshheading:9417057-Receptors, Cytoplasmic and Nuclear,
pubmed-meshheading:9417057-Type C Phospholipases
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pubmed:year |
1998
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pubmed:articleTitle |
Receptor-activated Ca2+ influx via human Trp3 stably expressed in human embryonic kidney (HEK)293 cells. Evidence for a non-capacitative Ca2+ entry.
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pubmed:affiliation |
Department of Pharmacology and Neurobiotechnology Center, Ohio State University, Columbus, Ohio 43210, USA.
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pubmed:publicationType |
Journal Article,
Research Support, U.S. Gov't, P.H.S.
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