Linked Life Data

14701836

Source:http://linkedlifedata.com/resource/pubmed/id/14701836

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
12
pubmed:dateCreated
2004-3-15
pubmed:abstractText
Aquaporin-1 (AQP1) is a membrane channel that allows rapid water movement driven by a transmembrane osmotic gradient. It was claimed to have a secondary function as a cyclic nucleotide-gated ion channel. However, upon reconstitution into planar bilayers, the ion channel exhibited a 10-fold lower single channel conductance than in Xenopus oocytes and a 100-fold lower open probability (<10(-6)) of doubtful physiological significance (Saparov, S. M., Kozono, D., Rothe, U., Agre, P., and Pohl, P. (2001) J. Biol. Chem. 276, 31515-31520). Investigating AQP1 expressed in human embryonic kidney cells, we now have shown that the discrepancy is not due to alterations of AQP1 properties upon reconstitution into bilayers but rather to regulatory processes of the oocyte expression system that may have been misinterpreted as AQP1 ion channel activity. As confirmed by laser scanning reflection microscopy, from 0.8 to 1.4 x 10(6) AQP1 copies/cell contributed to osmotic cell swelling. The proper plasma membrane localization was confirmed by observing the fluorescence of the N-terminal yellow fluorescent protein tag. Whole-cell patch clamp experiments of wild type or tagged AQP1-expressing cells revealed that neither cGMP nor cAMP mediated ion channel activity. The lack of significant CNG ion channel activity rules out a secondary role of AQP1 water channels in cellular signal transduction.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
19
pubmed:volume
279
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
11364-7
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2004
pubmed:articleTitle
Aquaporin-1, nothing but a water channel.
pubmed:affiliation
Forschungsinstitut fuer Molekulare Pharmakologie, Robert-Roessle-Strasse 10, D-13125 Berlin, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't