Linked Life Data

15342342

Source:http://linkedlifedata.com/resource/pubmed/id/15342342

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
2004-11-4
pubmed:abstractText
Previous studies on the activation mechanism of canonical transient receptor potential (TRPC) channels have often produced conflicting conclusions. All seven have been shown to be activated by phospholipase C (PLC)-coupled receptors, but TRPC1, TRPC2, TRPC3, TRPC4, TRPC5, and TRPC7 have also been proposed to function as store-operated channels.(1)1Although PLC activation inevitably leads to activation of store-operated channels, in this report when we refer to PLC-activated channels, we mean those channels that are specifically activated by PLC independently of store depletion. In the case of TRPC3, the expression environment and the expression level appear to determine the mode of regulation. Evidence of a close structural relative of TRPC3, TRPC7, has been presented that this channel is activated by receptor activation or by store depletion. On the basis of previous findings for TRPC3, we reasoned that subtle differences in structure or expression conditions might account for the apparent distinct gating mechanisms of TRPC7. To reexamine the mode of activation of TRPC7, we stably and transiently transfected human embryonic kidney (HEK)-293 cells with cDNA encoding for human TRPC7. We examined the ability of a PLC-activating agonist and an intracellular Ca(2+) store-depleting agent to activate these channels. Our findings demonstrate that when transiently expressed in HEK-293 cells, TRPC7 forms channels that are activated by PLC-stimulating agonists, but not by Ca(2+) store depletion. However, when stably expressed in HEK-293 cells, TRPC7 can be activated by either Ca(2+) store depletion or PLC activation. To our knowledge, this is the first demonstration of a channel protein that can be activated by both receptor- and store-operated modes in the same cell. In addition, the results reconcile the apparently conflicting findings of other laboratories regarding TRPC7 regulation.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Barium, http://linkedlifedata.com/resource/pubmed/chemical/Calcium Channels, http://linkedlifedata.com/resource/pubmed/chemical/Enzyme Inhibitors, http://linkedlifedata.com/resource/pubmed/chemical/Ion Channels, http://linkedlifedata.com/resource/pubmed/chemical/Membrane Proteins, http://linkedlifedata.com/resource/pubmed/chemical/TRPC Cation Channels, http://linkedlifedata.com/resource/pubmed/chemical/TRPC2 protein, human, http://linkedlifedata.com/resource/pubmed/chemical/TRPC3 cation channel, http://linkedlifedata.com/resource/pubmed/chemical/TRPC6 protein, human, http://linkedlifedata.com/resource/pubmed/chemical/TRPC7 protein, human, http://linkedlifedata.com/resource/pubmed/chemical/TRPM Cation Channels, http://linkedlifedata.com/resource/pubmed/chemical/TRPM2 protein, human, http://linkedlifedata.com/resource/pubmed/chemical/Thapsigargin, http://linkedlifedata.com/resource/pubmed/chemical/Type C Phospholipases
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0363-6143
pubmed:author
pubmed:issnType
Print
pubmed:volume
287
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
C1709-16
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
2004
pubmed:articleTitle
Canonical transient receptor potential TRPC7 can function as both a receptor- and store-operated channel in HEK-293 cells.
pubmed:affiliation
National Institute of Environmental Health Sciences, PO Box 12233, Research Triangle Park, NC 27709, USA.
pubmed:publicationType
Journal Article