Linked Life Data

10893422

Source:http://linkedlifedata.com/resource/pubmed/id/10893422

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
38
pubmed:dateCreated
2000-11-3
pubmed:abstractText
Although it is generally recognized that cystic fibrosis transmembrane conductance regulator (CFTR) contains a PSD-95/Disc-large/ZO-1 (PDZ)-binding motif at its COOH terminus, the identity of the PDZ domain protein(s) that interact with CFTR is uncertain, and the functional impact of this interaction is not fully understood. By using human airway epithelial cells, we show that CFTR associates with Na(+)/H(+) exchanger (NHE) type 3 kinase A regulatory protein (E3KARP), an EBP50/NHE regulatory factor (NHERF)-related PDZ domain protein. The PDZ binding motif located at the COOH terminus of CFTR interacts preferentially with the second PDZ domain of E3KARP, with nanomolar affinity. In contrast to EBP50/NHERF, E3KARP is predominantly localized (>95%) in the membrane fractions of Calu-3 and T84 cells, where CFTR is located. Moreover, confocal immunofluorescence microscopy of polarized Calu-3 monolayers shows that E3KARP and CFTR are co-localized at the apical membrane domain. We also found that ezrin associates with E3KARP in vivo. Co-expression of CFTR with E3KARP and ezrin in Xenopus oocytes potentiated cAMP-stimulated CFTR Cl(-) currents. These results support the concept that E3KARP functions as a scaffold protein that links CFTR to ezrin. Since ezrin has been shown previously to function as a protein kinase A anchoring protein, we suggest that one function served by the interaction of E3KARP with both ezrin and CFTR is to localize protein kinase A in the vicinity of the R-domain of CFTR. Since ezrin is also an actin-binding protein, the formation of a CFTR.E3KARP.ezrin complex may be important also in stabilizing CFTR at the apical membrane domain of airway cells.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
22
pubmed:volume
275
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
29539-46
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
E3KARP mediates the association of ezrin and protein kinase A with the cystic fibrosis transmembrane conductance regulator in airway cells.
pubmed:affiliation
Department of Cell Biology and Physiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't