Linked Life Data

12634930

Source:http://linkedlifedata.com/resource/pubmed/id/12634930

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2003-3-13
pubmed:abstractText
The family of epithelial Ca(2+) channels (ECaC) is a unique group of highly Ca(2+)-selective channels consisting of two members, ECaC1 and ECaC2. We used carboxyl terminal truncations and mutants to delineate the molecular determinants of the Ca(2+)-dependent inhibition of ECaC. To this end, rabbit ECaC1 was expressed heterologously with green fluorescent protein (GFP) in human embryonic kidney 293 (HEK293) cells using a bicistronic vector. Deletion of the last 30 amino acids of the carboxyl terminus of ECaC1 (G701X) decreased the Ca(2+) sensitivity significantly. Another critical sequence for Ca(2+)-dependent inactivation of ECaC1 was found upstream in the carboxyl terminus. Analysis of truncations at amino acid 635, 639, 646, 649 and 653 disclosed a critical sequence involved in Ca(2+)-dependent inactivation at positions 650-653. C653X showed decreased Ca(2+) sensitivity, comparable to G701X, while E649X lacked Ca(2+)-dependent inactivation. Interestingly, the number of green fluorescent cells, which is an index of the number of transfected cells, was significantly smaller for cells transfected with truncations shorter than E649 than for cells transfected with wild-type ECaC. However, the expression level of GFP was restored in the presence of the ECaC blocker ruthenium red, suggesting that these truncations resulted in deleterious Ca(2+) influx. In conclusion, we have identified two domains in the carboxyl terminus of ECaC1 that control Ca(2+)-dependent inactivation.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0031-6768
pubmed:author
pubmed:issnType
Print
pubmed:volume
445
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
584-8
pubmed:dateRevised
2007-7-6
pubmed:meshHeading
pubmed:year
2003
pubmed:articleTitle
The carboxyl terminus of the epithelial Ca(2+) channel ECaC1 is involved in Ca(2+)-dependent inactivation.
pubmed:affiliation
Department of Physiology, Campus Gasthuisberg, KU Leuven, Herestraat 49, 3000 Leuven, Belgium. bernd.nilius@med.kuleuven.ac.be
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't